Chapter 11 Common obstetric techniques, procedures, and surgery

Balloon tamponade

Caesarean section

Forceps delivery

Uterine compression sutures

Ventouse delivery

Balloon tamponade Definition

The insertion of a balloon device into the genital tract to control bleeding from the placental bed, and/or lacerations in the uterus, cervix, and vagina, by means of pressure effect when the balloon is inflated with fluid.

The actual incidence of the use of balloon tamponade in the management of PPH, and occasionally for the management of bleeding from a cervical pregnancy or lower genital tract laceration, remains unknown. There are only anecdotal case reports and small case series in the literature, but this most likely represents under-reporting. Pathology

PPH is the third most common cause of maternal mortality worldwide and accounted for 10% of the direct maternal deaths in the UK. There has been a progressive increase in the risk factors for PPH, such as the increasing prevalence of mothers with advanced age, multiple pregnancy, and a scarred uterus. Excessive bleeding can occur from a failure of the placental bed blood vessels to be occluded by the contracting myometrium. This can be consequent to the following:

• inadequate uterine contraction after the complete expulsion of the placenta, as in the case of uterine atony.

• inability of the uterus to contract effectively:

• partial separation of the placenta:

— morbidly adherent placenta (e.g. placenta accreta, placenta increta)

— inadequate, inappropriate, or delayed administration of oxytocic agent for the management of the third stage.

• completely separated placenta trapped inside the uterus due to:

— premature contraction of the cervix

— failed controlled cord traction following breaking of the cord

— narrowing, elongation, or distortion of the lower uterine segment after child birth from intramural (e.g. uterine fibroid) or extramural (e.g. non-pregnant horn of a bicornuate uterus) compression

— external pressure from a pelvic mass (e.g. distended urinary bladder)

— lacerations of the genital tract—from the uterus down to the vagina

• coagulapothy:

— disseminated intravascular coagulation (e.g. severe pre-eclampsia, abruptio placentae)

— consumptive coagulopathy resulting from the delayed, inadequate, or failure, of administration of blood product replacement in the management of postpartum haemorrhage.

Balloon tamponade can be used in almost any form of PPH, either as the primary surgical treatment or in conjunction with brace compression sutures. In PPH in which inadequate uterine contraction and retraction is a significant factor, or despite satisfactory uterine contraction, bleeding still continues from the placental bed or repaired lacerations, direct compression from within the uterus by a balloon device to produce a tamponade effect can often control the bleeding. In order for balloon tamponade to be effective, the uterus has to be able to contract in response to oxytocic stimulation, without or with the additional use of brace compression sutures on the uterus to prevent it from stretching. In the case of cervical pregnancy or cervical laceration in a non-pregnant uterus, direct compression of the bleeding site by balloon tamponade is often sufficient by itself to control the bleeding. Aetiology

PPH is usually categorized into four major groups as follows:

• uterine atony (tone)

• retained products of conception (tissue)

• genital tract lacerations (trauma)

• coagulopathy (thrombin).

Sometimes, a combination of causes can be found. Irrespective of the underlying cause(s), ineffective and/or delayed treatment can lead to consumptive coagulopathy, so that even when the primary cause is eliminated, bleeding continues unless the coagulopathy can be corrected.

Risk factors for postpartum haemorrhage

• Abruptio placentae

• Placenta praevia

• Multiple pregnancy

• Pre-elcampsia

• Nulliparity

• Previous PPH

• Obesity

• Caesarean section

• Retained placenta

• Instrumental vaginal delivery

• Prolonged labour (>12 hours)

• Big baby (>4.0 kg)

• Vaginal lacerations and episiotomy

• Uterine fibroid. Prognosis

Apart from mortality, PPH and its direct complications, together with the short- and long-term sequelae of various forms of treatment, can lead to serious maternal morbidity including end organ damage such as renal failure, Sheehan’s syndrome, and the effects of hysterectomy. Balloon tamponade is a safe treatment modality without creating any lasting effects since its use is usually restricted to 24 hours and the balloon can be deflated and removed any time without causing additional trauma or residual harm to the patient. In tying the patient over the critical period, balloon tamponade not only can save lives but also provides the opportunity for other forms of treatment and full resuscitation. No significant side-effects have been reported in association with the use of balloon tamponade.

Advantages of using balloon tamponade

• Easy administration and removal.

• Can ascertain effectiveness quickly.

• Allows continual assessment of blood loss that is drained through the catheter lumen.

• Can reduce the need for hysterectomy and other surgical procedures via laparotomy.

• The success rate of balloon tamponade is generally high in the reported cases/series, varying from 70% to 100%, with an average rate of around 80%. Clinical approach

Devices

The use of a number of devices has been reported, including devices ‘borrowed’ from other uses to purposely designed devices.

Sengstaken–Blakemore tube or Sengstaken–Blakemore oesophageal catheter

This is the most frequently reported device used for this purpose. Originally designed to stop bleeding from oesophageal varices, the Sengstaken–Blakemore (SB) tube consists of two balloons: a gastric and an oesophageal balloon.

Bakri tamponade balloon

This is designed for temporary management of lower segment bleeding and is less effective in the presence of uterine anatomical anomalies. For transvaginal placement, the recommendation is to insert the balloon portion beyond the internal os and under ultrasound guidance. For transabdominal placement following Caesarean delivery, the recommendation is to pass the inflation port of the balloon via the uterine incision, and then the shaft is pulled out through the uterus, cervix, and finally into the vagina until the deflated balloon base is in contact with the internal cervical os. The uterine incision is closed, taking care to avoid puncturing the balloon. The balloon is then inflated with sterile water or normal saline according to the product label for maximum inflation volume.

Rüsch urological hydrostatic balloon

This is designed as a hydrostatic (bladder distension) catheter. For application the catheter is inserted through the cervical canal into the uterine cavity and the balloon is then distended with 250–300 mL of normal saline. The distal end of the catheter shaft is pulled out of the vagina to achieve tamponade effect.

Foley catheter

The principle and method of application of the Foley catheter is similar to that of the other balloon catheters. However, for the postpartum uterus, the balloon of a Foley catheter is usually too small to be effective, and the use of multiple Foleys is cumbersome without any guarantee of effectiveness even if the catheters are enclosed in an overbag. Blood collected inside the uterus cannot be drained when using an overbag and therefore further haemorrhage is concealed. Therefore the use of the Foley catheter should be considered only in the absence of the other devices.

Condom hydrostatic tamponade

This simply involves the use of a single condom tied to a catheter introduced into the uterine cavity and then inflated with 250–300 mL of normal saline until the bleeding is controlled. The proximal end of the catheter is then folded and tied with thread to keep the saline from escaping. Rolled gauze is then packed into the vagina to keep the inflated condom in place for 24–48 hours. The disadvantage of this device is that any further bleeding inside the uterus may remain undiagnosed until much later. In addition, condoms are not readily available in the delivery suite or operation theatre. However, in a primary care setting, this may be the only available means to control bleeding for the transfer of patients to a better equipped centre for further management.

• The whole placenta, or the bulk of the placenta in case of placenta accreta, should have been removed first.

• The patient is placed in the lithotomy position in the operation theatre. General or regional anaesthesia is preferred, but not necessarily so, for this procedure, which can be performed under sedation and other forms of analgesia.

• A Foley catheter is placed in the bladder for continuous urinary drainage.

• The balloon portion of the catheter is then inserted through the cervix in case of vaginal delivery. In case of Caesarean delivery, the balloon portion is placed inside the uterine cavity under direct vision with the rest of the catheter and injection portal pushed into the vagina through the cervix and then led outside the vagina by an assistant. If the uterine incision has been closed already, the device can be introduced, as in the case following vaginal delivery, by an assistant, with the rest of the catheter and the injection portal led outside the vagina while the surgeon observes the progress. Further surgical treatment can be carried out immediately if the tamponade test fails.

• The balloon is inflated with warm normal saline, with the objective to completely fill up and compress against the uterine cavity or the site of bleeding. The volume is therefore variable according to the degree of uterine volume.

• The presence of bleeding from inside the uterus can be gauged from the amount of blood drained from the drainage port of the catheter, which can be collected in a graduated bag connected to the opening of the catheter.

• The balloon and catheter is secured in place by means of gauze rolls soaked with iodine or antibiotic packed into the vaginal canal until there is no room for the catheter to move about. The packing should be performed gently so as to avoid superficial abrasion to the already oedematous or raw surface of the vagina and cervix. Excessive packing should be avoided so as to prevent excessive stretching and iatrogenic laceration to the tissues of the lower genital tract.

• After packing and stabilization of the balloon, the position of the uterine fundus and outline of the uterus should be traced with a marking pen on the abdominal wall (after closure of the abdomen first in case of Caesarean delivery) so as to identify changes in the uterine size and shape, which could reflect blood collection inside the uterus or the development of broad ligament haematoma, hence calling for further actions.

• The balloon should be kept for at least 12 hours, but not more than 24 hours. The pack and the balloon can be removed in phases, first the pack and then the balloon. For removal, the balloon should be deflated by aspiration of the contents followed by gentle withdrawal from the uterus. There is no need for swabbing the balloon for culture afterwards.

• In case of deterioration of vital signs, or evidence of continued and unabated bleeding, or features suspicious of an enlarging pelvic collection, tamponade treatment should be considered a failure and other measures should be undertaken.

• The findings and procedure should be clearly documented in the notes and the condition explained to the patient afterwards, especially in the case of placenta praevia and accreta, where placental fragments may be left behind. Postoperative management

• Adequate and appropriate analgesia is necessary

• Prophylaxis for deep vein thrombosis should be undertaken. Initially physiotherapy and compression stockings can be prescribed. Anticoagulant therapy should be avoided for the initial 24–48 hours for obvious reasons. The patient should be encouraged to ambulate within 24 hours and to start walking around, with help if necessary, after the first day or removal of the balloon device. Anticoagulant therapy with prophylactic dose of unfractionated heparin or low molecular weight heparin should be commenced afterwards according to the protocol for the prophylaxis against postoperative thromboembolism.

• Bladder drainage with the Foley catheter should be maintained until the balloon is removed, and preferably until the sensation of the lower abdomen and perineum has returned (in case of epidural analgesia and patient controlled analgesia).

• Prophylactic antibiotic should be given, covering both aerobic and anaerobic organisms, and commencing with intravenous injection for the first 24–48 hours then continuing with oral treatment. If fragments of placental tissue remain inside the uterus, or if the Foley catheter is still required beyond the first 24 hours, or if there is any suspicion of endometritis, antibiotic prophylaxis should be continued for 1 week or until the culture results are available, or until symptoms and signs of infection have completely subsided. Otherwise, the antibiotic treatment can be discontinued after 72 hours.

• Attention should be paid to maintain fluid balance, and to avoid fluid overload.

• Oral intake can be resumed gradually as for other postoperative patients. Constipation frequently occurs in the first few days. To avoid straining at defecation, stool softeners and bulk agents can be prescribed from the time oral intake is allowed until discharge from hospital.

• Before discharge, the patient should be warned about the potential problems, including infection and secondary postpartum haemorrhage, if fragments of placental tissue are left in situ. Early postnatal visit should be arranged to assess the condition. Further investigations including ultrasound assessment may be required. Follow-up visits should be arranged until return of menstruation. Sheehan syndrome may need to be excluded if there is prolonged amenorrhoea in the absence of breast feeding. Further reading

ACOG Practice Bulletin: Clinical Management Guidelines for Obstetrician-Gynecologists Number 76, October 2006: postpartum hemorrhage. Obstet Gynecol 2006;108:1039–47.

Akhter S, Begum MR, Kabir J. Condom hydrostatic tamponade for massive postpartum hemorrhage. Int J Gynecol Obstet 2005;90:134–5.

Condous GS, Arulkumaran S, Symonds I, et al. The ‘tamponade test’ in the management of massive postpartum hemorrhage. Obstet Gynecol 2003;101:767–72.

Dabelea V, Schultze PM, McDuffie RS Jr. Intrauterine balloon tamponade in the management of postpartum hemorrhage. Am J Perinatol 2007;24:359–64.

Danso D, Reginald P. Combined B-Lynch suture with intrauterine balloon catheter triumphs over massive postpartum haemorrhage. Br J Obstet Gynaecol 2002; 109: 963.

Doumouchtsis SK, Papageorghiou AT, Vernier C, Arulkuraman S. Management of postpartum hemorrhage by uterine balloon tamponade: prospective evaluation of effectiveness. Acta Obstet Gynecol Scand 2008;87:849–55.

Ferrazzani S, Guariglia L, Triunfo S, et al. Successful treatment of post-cesarean hemorrhage related to placenta praevia using an intrauterine balloon. Two case reports. Fetal Diagn Ther 2006; 21; 277–80.

Frenzel D, Condous GS, Papageorghiou AT, McWhinney NA. The use of the ‘tamponade test’ to stop massive obstetric haemorrhage in placenta accrete. Br J Obstet Gynaecol 2005;112:676–7.

Fylstra D, Coffey MD. Treatment of cervical pregnancy with cerclage, curettage and balloon tamponade: a report of three cases. J Reprod Med 2001;46:71–4.

Johanson R, Kumar M, Obhrai M, Young P. Management of massive postpartum haemorrhage: use of a hydrostatic balloon catheter to avoid laparotomy. Br J Obstet Gynaecol 2001;108:420–2.

Okeahialam MG, Tuffnell DJ, O’Donovan P, Sapherson DA. Case report. Cervical pregnancy managed by suction evacuation and balloon tamponade. Eur J Obstet Gynecol Reprod Biol 1998;79:89–90.

Ramanathan G, Arulkumaran S. Postpartum haemorrhage. Curr Obstet Gynaecol 2006;16:6–13.

Royal College of Obstetricians and Gynaecologists (RCOG) Placenta praevia and placenta praevia accrete. Clinical Green top Guidelines. London: RCOG 2005.

Seror J, Allouche C, Elhaik S. Use of Sengstaken-Blakemore tube in massive postpartum hemorrhage: a series of 17 cases. Acta Obstet Gynecol Scand 2005;84:660–4.

Tattersall M, Braithwaite W. Balloon tamponade for vaginal lacerations causing severe postpartum haemorrhage. Br J Obstet Gynaecol 2007;114:647–8. Internet resources

www.cookmedical.com Patient information and contacts

www.rcog.org.uk

Caesarean section Definition

Caesarean section (CS) refers to a form of operative delivery in which the infant is delivered through the abdomen via skin and uterine incisions. Epidemiology

There is a progressive increase in the prevalence of CS worldwide. The increase in primary CS rates was attributable to a number of factors, including changes in practice and perceived benefits for the mother and infant, changes in maternal anthropometric characteristics such as older age, higher pre-pregnancy body mass index (BMI) and gestational weight gain, short stature, increased fetal size, the increased incidence of a scarred uterus, and the lower threshold for Caesarean versus other forms of operative vaginal delivery, especially in the presence of obstetric complications. The changing medicolegal climate also plays direct and indirect roles. In the USA, the overall rate for primary CS in 2002 was 25.8% and 13.3% for first child versus second child or later. The rate showed a progressive increase from 17.8% in women 40 years old for the first child, and from 11.3% to 23.8% respectively for the second child and after. The changing maternal and fetal risk profiles means that there is no such thing as an ideal CS rate, and any target rate set must be realistic and reviewed periodically for appropriate adjustments. Pathology

Maternal morbidity associated with CS increases with increasing number of CSs. There are direct and indirect maternal and perinatal morbidities, which could lead to mortality if overlooked or mismanaged.

Direct maternal morbidity

Compared with vaginal delivery, both elective and intrapartum CS are associated with increased risk of severe maternal morbidity. However, when compared with induction of labour at term, CS without labour was associated with less early postpartum haemorrhage and composite maternal morbidity, whereas the highest morbidity was found in the CS in labour group. The occurrence of serious or multiple morbidities may necessitate admission to the intensive care unit, and the rate for the first to the sixth or later CS was 1.85%, 0.57%, 0.54%, 1.58%, 1.94%, and 5.62% respectively. The rate of major complications was 4.3%, 7.5%, and 12.5% for the second, third, and fourth or more CS respectively. Overall, women with multiple CS have increased risk of excessive blood loss, dense adhesions, placenta accreta, and hysterectomy.

Infection

• Metritis and endometritis: the rate was shown to be highest in the first (5.98%) and sixth or later (6.74%) CS, but much lower for the second to fifth CS (1.55–2.96%)

• Wound infection: this is a common complication especially for emergency CS, and the rates varied from 1.53% for the first CS to 3.37% for the sixth or later CS.

• Septicaemia

• Chest infection.

Haemorrhage

• Uterine atony

• Uterine lacerations

• Poor surgical techniques

• Underlying pathologies, e.g. uterine fibroids.

Surgical trauma and injuries to neighbouring organs

• Bladder injury/cystotomy: the rates increase from 0.13%, 0.09%, 0.28%, 1.17%, 1.94%, to 4.49% respectively from the first to the sixth or later CS.

• Ureteric injury: the rates increase from 0.03%, 0.01%, 0.02%, 0.07%, 0.39% to 1.12% respectively from the first to the sixth or later CS.

• Bowel injury: the correlation with the number of CS is more variable, from 0.11%, 0.06%, 0.13%, 0.34%, 0%, to 1.12% respectively from the first to the sixth or later CS.

• Omental injury.

Hysterectomy

The risk is correlated with the number of CS, and the rate increases from 0.65%, 0.42%, 0.90%, 2.41%, 3.49% to 8.99% respectively from the first to the sixth or later CS, and the corresponding odds ratios from the second to the sixth or later CS were 0.7, 1.4, 3.8, 5.6 and 15.2 respectively.

Wound complications

• Haematoma

• Pain

• Dehiscence: the rate is generally low to 0.47% in the vaginal versus CS groups (OR 3.0), and to 0.2% in the elective CS group (not significant).

• Transient tachypnoea of newborn—the rate was increased from 1.1% for vaginal deliveries to 3.5% for all CS, and 3.1% for elective CS (OR 3.3 and 2.8 respectively).

• Persistent pulmonary hypertension—the rate was increased from 0.08% for vaginal delivery, to 0.4% and 0.37% for total and elective CS (OR 4.9 and 4.6 respectively).

Breastfeeding and weight loss

• CS is one of the factors in delayed onset of lactation (>72 hours), which in turn contributes to excess neonatal weight loss.

Factors affecting likelihood of adverse maternal and perinatal outcomes

• Maternal obesity: adverse perinatal outcome is increased with increasing maternal BMI, which also increases the difficulty of the operation and the risk of most peri- and postoperative complications.

• Timing of operation: elective CS before labour is associated with the lowest maternal and perinatal risks, especially in high-risk cases where adequate preparations can be undertaken to prevent complications. The incidence of fetal injury was 0.5% for elective repeat CS. For intrapartum CS, maternal and neonatal morbidity is increased in the second compared with first stage CS, including uterine atony, uterine incision extension, cystotomy, and neonatal injury.

• Indications for CS: most indications were associated with a low rate of fetal injury between 0.7% and 1.5%. The exception is failed instrumental delivery (ventouse or forceps), both for primary CS (6.9%), and for CS for failed VBAC (1.7%).

• Type of uterine incision: the incidences of fetal injury for ‘T’ or ‘J’ incision, vertical incision, and low transverse incision were 3.4%, 1.4%, and 1.1% respectively.

• Speed of the delivery: among neonates with injuries, the rate was correlated with the skin incision to delivery interval. The rate of injury decreased from 1.9% for an interval of ≤3 minutes, to around 1.0% for intervals of 6 minutes or more.

• Decision–incision interval: one study revealed that 65% of the primary emergency CS began within 30 minutes of the decision to operate. Maternal morbidity was not related to this factor, but neonatal compromise in the form of umbilical arterial pH 30 minutes. This may be related to the indication for CS. Aetiology

A number of conditions are associated with increased likelihood of CS for medical reasons. There are a number of general conditions such as anthropometric parameters that are associated with, and on occasions become indications for, CS. These conditions probably act as surrogates for other underlying conditions. There are some factors which have been utilized as predictors of CS, but which by themselves are not true indications. Indications should be reserved to describe specific conditions in which the maternal and/or fetal risks are so significantly increased that vaginal birth is not an acceptable option.

Factors associated with increased risk of CS

Maternal weight, BMI, and obesity

A significant linear association between maternal BMI and risk of CS has been demonstrated, with the leanest mothers having the highest rate of vaginal delivery, while CS rates increased with increasing BMI, being highest in the morbidly obese, when confounding factors such as gestational diabetes, delivery ≥37 weeks, maternal height 12 hours

• Epidural analgesia

• Clinical chorioamnionitis

• Internal fetal monitoring

• Fetal weight ≥4000 g

• Labour induction

• Labour augmentation with oxytocin

• Advanced maternal age (≥35 years)

• Latent phase ≥12 hours

• Meconium-stained liquor.

Indications for CS

Maternal (relative rather than absolute)

• Uterine anomalies

• Uterine fibroids

• Uterine scars

• Contracted/deformed pelvis

• Cardiorespiratory complications

• Severe hypertension

• Neurological conditions

• Previous pelvic trauma/anal sphincter damage

• Cervical factors.

Maternal benefits of CS

The main benefit is the prevention of deterioration in the physical condition or development of complications that are attributable to the physical stress of the labour and delivery process. The rationale behind performing CS for preserving/protecting sexual function and health through the avoidance of perineal/vaginal trauma and scarring is questionable in the absence of previous third/fourth-degree tear. Although there is some evidence that there is a protective effect in the first 3 months postpartum, there is little evidence to support any long-term difference or benefits of CS in this aspect.

Fetal/neonatal

• Cephalopelvic and fetopelvic disproportion.

• Congenital anomalies.

• Malpresentation and abnormal fetal lie: abnormal fetal lie such as transverse and oblique lie, and compound and brow presentation are absolute indications for CS. Although CS for breech presentation has been controversial, current evidence is in favour of planned CS in breech presentation for better perinatal and neonatal outcomes.

• Impaired placental function and fetal growth restriction: a small fetus is by no means an indication for CS, since there is reduced risk of disproportion. However, for suspected fetal growth restriction with evidence of placental insufficiency, such as absent/reversed umbilical end diastolic flow, the fetus is most unlikely to be able to tolerate the stress of labour and vaginal delivery.

• Placenta praevia: even for minor praevia, if there is any obstruction to the descend/engagement of the fetal head, CS should be performed.

• Fetal distress/hypoxia/compromise

• Multifetal pregnancy.

Fetal/neonatal benefits of Caesarean section

In infants born to nulliparous women, the risk of intracranial haemorrhage is higher among those delivered by ventouse extraction (OR 2.7), forceps delivery (OR 3.4), and intrapartum Caesarean section (OR 2.5), with no significant difference among these three groups when compared with infants delivered spontaneously. However, the risk among infants delivered by CS before labour was not higher. This suggested that abnormal labour is the common risk factor for intracranial haemorrhage. Overall risk in breech presentation and risk of intrapartum fetal death in cephalic presentation are reduced by CS. Prognosis

Maternal and infant wellbeing

Elective CS was shown to be associated with a significantly lower rate of maternal and fetal complications than vaginal birth. Birth experience, as assessed by the Salmon Test, was significantly better in elective CS than vaginal delivery, but was worse in women with emergency CS and worst in women with vacuum delivery. For the next pregnancy, 83.5%, 74.3%, 66%, and 30.1% respectively would choose the same mode of birth for vaginal, elective CS, medically indicated CS, and emergency CS.

Pelvic structures and function

Urinary incontinence

When compared with nulliparous women, women with previous CS have increased risk of stress or mixed type of urinary incontinence (adjusted OR 1.5 for any incontinence, 1.4 for moderate or severe incontinence). However, compared with CS, vaginal delivery is associated with further increase in urinary incontinence (adjusted OR 1.7 for any incontinence and 2.2 for moderate or severe incontinence).

Faecal incontinence

At 6 years after their first delivery, women who had CS, or those who had exclusive CS, showed less risk of persistent faecal incontinence than women who had spontaneous vaginal delivery.

Sexual function and health

CS is thought to protect sexual health after childbirth by avoiding perineal trauma. A study in primiparous women revealed that when compared with vaginal delivery, CS was protective against dyspareunia-related symptoms, but only for the first 3 months after delivery. At 6 months, there were no significant differences in dyspareunia-related symptoms, sexual response-related symptoms, and post-coital problems.

Future fertility

There are few data regarding the effect of one previous CS on subsequent fertility, but there is no evidence to suggest that the uterine scar impacts on the chances of subsequent conception. There is however increased risk of miscarriage and ectopic pregnancy.

Future pregnancy outcome

Pregnancy complications

• Stillbirth: it has been reported that women who had a previous CS have increased risk of a subsequent unexplained antepartum stillbirth, but this association could not be proven in a subsequent study.

• Placenta praevia: this risk is highly correlated with parity and the number of previous CS, and the rate increases from 1.33%, 1.14%, 2.27%, 2.33%, and 3.37% after the first to the sixth or later CS. In general, the risk for placenta praevia in the second pregnancy after a previous CS was 1.47 to 1.5, and 1.7 if the second pregnancy was within 1 year after the CS.

• Placental abruption: the rate of abruption after one previous CS was 0.95% versus 0.74% in women with a vaginal delivery, and the risk for abruption after one or two consecutive CS was 1.3–1.4. The risk for a second pregnancy within 1 year after a CS was 1.5.

• Placenta accreta/increta/percreta: the incidence of placenta accreta increased progressively from the second to the sixth or later CS, being 0.31%, 0.57%, 2.13%, 2.33%, and 6.74% respectively, and the odds ratio was 1.3, 2.4, 9.0, 9.8, and 29.8 respectively. The occurrence of placenta accreta was influenced by the coexistence of placenta praevia. The rates for the second to the sixth or later CS with and without placenta praevia were 11%, 40%, 61%, 67%, and 67%, versus 0.2%, 0.1%, 0.8%, 0.8% and 4.7%, respectively. The presence of placenta accreta increased comorbidities that included injury to other pelvic organs, thromboembolic complications, and intensive care unit admission.

• Scar dehiscence/uterine rupture: the overall rate of symptomatic rupture was 0.7%, and the rates of rupture were reported to be 1.5% versus 0.5% versus 0.3% in women without vaginal birth versus vaginal birth prior to CS versus prior VBAC. The rate of uterine rupture in VBAC was similar between women with multiple or single prior CS, being 0.9% and 0.7% respectively. One study found that for spontaneous labour, the rupture rate was 0.5% before and 1.0% after 40 weeks, while the corresponding figures for induced labour were 2.1% and 2.6% respectively. In contrast another study reported that the rupture rate increased significantly from 0.4% before to 2.1% after 40 weeks for spontaneous labour, without any corresponding increase in the rate of CS, or maternal and perinatal morbidity.

Labour and trial of scar (VBAC)

• Effect of previous vaginal deliveries: previous vaginal delivery and VBAC are associated with higher rates of successful VBAC in the index pregnancy. One study found that the success rates were 70.1%, 81.8% and 93.1% in women with no vaginal delivery, one vaginal delivery before the previous CS, and a prior VBAC respectively, whereas the rates of third/fourth degree tears and operative vaginal deliveries were 8.5%, 2.5% and 3.7%, and 14.7%, 5.6% and 1.9% respectively.

• Number of previous CS: although some reports suggested that VBAC can be an option in women with two previous CS, most obstetricians have reservations due to the higher rates of complications and morbidity.

• Maternal BMI: in general, the success rate of VBAC diminishes with increasing BMI, from 83.1% in the under-weight to 68.2% in the obese categories, and obese women have half the likelihood (OR 0.53) compared with underweight women. As well, there is increased risks of uterine rupture/scar dehiscence, composite maternal morbidity, and neonatal injury.

• Induced labour: this increases the early postpartum haemorrhage (OR 1.66), CS (OR 1.84), and NICU admission for the neonate (OR 1.69). The limited literature also suggested that using prostaglandin analogues like misoprostol for labour induction increased significantly the risk of uterine rupture (9.7%).

Gestational age at VBAC: it was reported that the rate of CS increased significantly from 25% to 33.5% and from 33.8% to 43% before and after 40 weeks for spontaneous and induced labour respectively. Another study showed no significant difference in the CS rates for spontaneous labour before (34.1%) and after (40.4%) 40 weeks, but labour induction increased these figures significantly to 64.6% and 52% respectively. In general, the success rate for VBAC was not increased in spontaneous labour after 40 weeks compared with induced labour before 40 weeks, so that the advantage of awaiting for spontaneous labour to occur after 40 weeks is really to avoid induction, which may increase the risk of uterine rupture.

• Other outcomes: there is increased risks of endometritis (2.9% versus 1.8%) and blood transfusion (1.7% versus 1.0%), but the greater risk is one of neonatal hypoxic-is-chaemic encephalopathy (0.08% versus 0%), the majority of which was related to uterine rupture, when compared with repeat elective CS. As for the type of previous uterine incision, the limited literature suggested that a prior lower segment vertical incision is similar to a transverse incision with respect to maternal perinatal safety and the likelihood of successful outcome.

Repeat CS

The difficulties in repeat CS are related to the number of previous CS, and the incidences of complications are correlated with the number of previous operations. Multiple prior CS was associated with increased rates of hysterectomy (0.6% versus 0.2%), transfusion (3.2% versus 1.6%), and overall maternal morbidity (OR 1.41)

Preterm (sheath, care must be exercised to look for and avoid cutting right through to any adherent tissue below, which may be bowel loops, the gravid uterus, or omentum. Locate a window and open this up using artery forceps and scalpel, enlarging it by stretching with the index fingers, and then with scissors if necessary and only after exclusion of adherent organs. Look for the window as close to the umbilicus as possible to avoid opening into the adherent and stretched bladder instead, since it is not possible to know in advance whether the bladder is pulled upwards underneath the rectus sheath. Adhesions should be freed by sharp and blunt dissection and bleeding vessels transfixed with stitches. Diathermy should be avoided as far as possible.

Lower transverse skin incisions

The advantage of this type of incision is that it is adequate for the great majority of CS (but this is obviously dependent on the surgeon’s skills and experience), is cosmetically more acceptable, and is associated with less pain especially during ambulation in the first few days after delivery. Furthermore, there is minimal chance of incisional hernia and of burst abdomen. The types of incisions are described below.

• Pfannenstiel incision: this is the classical skin incision. It is a crescent-shaped suprapubic incision at/above the pubic hairline (or at two fingers’ breadths above the pubic symphysis) and curving slightly upwards at both ends towards the anterior superior iliac spines, and ideally placed along a natural fold of skin. The length should be assessed as adequate to allow easy passage of the fetal head. The dissection is carried through the subcutaneous tissue to the rectus sheath, which is incised transversely, and the incision is extended laterally with the fascial edges being elevated under tension with toothed clamps to allow sharp and blunt dissection of the underlying muscles. The rectus muscles are separated in the midline with blunt dissection. Any bleeding vessels are electrocoagulated. The peritoneum is opened in the midline with sharp dissection and then extended longitudinally to expose the intraperitoneal contents.

• Joel Cohen incision: this is a straight horizontal incision placed at a higher level (3 cm above the pubic symphysis). The subcutaneous tissue and rectus sheath are opened only for about 3 cm in the midline, and the rectus sheath incision is extended laterally and separated from the muscles with blunt dissection using fingers. The rectus muscles are separated in the midline by stretching caudally and cranially with the index fingers, and then the muscles, fascia, and subcutaneous tissues are pulled gently and evenly to both sides by means of the index and middle fingers of the operator and assistant to create an appropriately sized orifice that will allow the head to be delivered. The peritoneum is similarly opened by means of stretching longitudinally with the fingers. The advantages of this approach is that it is restrictive in the use of sharp dissection and respect the anatomical structures with minimal tissue trauma and quicker postoperative recovery, less febrile reaction, less bleeding in the abdominal wall, less need for antibiotics and analgesics, fewer peritoneal adhesions and less scarring, and earlier return of bowel function. It is also quicker and suitable for emergency CS. This method is also known as the Misgav Ladach method, and is endorsed as the incision of choice by NICE.

• In practice, an approach combining the best of both methods or slight modifications can be applied depending on the circumstances. The Joel Cohen skin incision could create an unsightly guttering effect in an erect posture especially in women with certain amount of abdominal subcutaneous fat.

Uterine incision

Classical

This is seldom used but may be necessary for abnormal lie and presentation, especially in relation to a major placenta praevia or lower segment uterine fibroid(s) that displaces the fetus upwards towards the fundus, or fetal problems such as a large tumour that causes fetal malpresentation and abnormal lie. In the case of placenta praevia with suspected placenta accreta, this approach can avoid disturbing the placenta which is left in situ to be dealt with by uterine artery embolization and/or methotrexate treatment. In this way, excessive bleeding and potential hysterectomy with risk of injury to the lower urinary tract can be avoided. This is a vertical incision in the upper segment, preferably made along the midline, the length of which depends on the fetal size and indication. The incision can sometime extend spontaneously with manipulation at delivery; therefore, avoid making the initial incision up to the fundus.

Lower segment transverse

Also known as Kerr’s incision, the uterovesical fold of peritoneum is opened with sharp dissection and the bladder is pushed downwards gentle to expose the lower segment of the uterus. Sharp dissection may be necessary if there are adhesions. A 2–3-cm curvilinear incision is made in the midline of the exposed lower segment about 2–3-cm below the peritoneal reflection, avoiding the rupturing of the membranes so that the amniotic fluid will not be drained before the infant is delivered. The incision is extended laterally with gentle traction using the index fingers hooked below the uterine wall and avoiding extension to the broad ligaments.

Lower segment vertical

Also known as DeLee’s incision, a similar-sized incision is made at the same spot but in a longitudinal manner, and the orifice is enlarged by stretching of the two sides laterally with the index fingers, carefully avoiding the lower end extending into the cervix and vagina.

Extension of the initial incision

This may be necessary in the case of a poorly formed lower segment or for the delivery of a preterm infant especially with malpresentation. A J-extension to the lower segment incision is, usually from the end of the incision on the side opposite to that of the operator and extending towards the upper segment, or a U-extension at both ends may be necessary to enlarge the incision to create more room for the manipulation and delivery of the infant. This can be done with a pair of heavy curved scissors. Never direct an extension downwards towards the cervix and bladder. Inverted T-extension should be avoided unless there is no amniotic fluid and/or the infant is stuck with transverse lie/compound presentation.

Delivery of the fetus in singleton pregnancy

Cephalic presentation

The position and degree of flexion of the fetal head should be determined preferably before cutting the membranes, and the subsequent steps should be decided before the fingers are inserted into the uterus. Once the membranes are cut, try to insert the fingers of the right hand alongside the fetal head/face to below the vertex and rotating the head to an occipital anterior position simultaneous with upward traction and correction of any asynclitism and deflexion. For a high head, low cavity forceps with no/minimal pelvic curve should be used to deliver the head. This is followed by the rest of the trunk but avoid hasty delivery of the shoulders especially for a macrosomic infant, as extensive tearing of the angles of the Kerr’s incision, especially into the broad ligament and/or downwards towards the cervix and bladder, can occur with disastrous consequence.

Breech presentation

The type of breech and position of the sacrum should be determined before attempted manipulations, and similar manoeuvres to those for vaginal delivery are used. Avoid excessive pressure applied to the body or the limbs during traction/rotation, as injury to the internal organs and fractures of the limb bones are known complications. Forceps can similarly be used for delivery of the after-coming head.

Transverse/oblique lie

It is most important to avoid cutting the membranes and draining the amniotic fluid if abnormal lie is known before the uterine incision. The author’s preference is to perform external podalic version first, then ask the assistant to stabilise the fetus and apply fundal pressure to bring the fetal limbs to the level of the uterine incision, preferably into the fetal sac that is already bulging out, before cutting the membranes with a toothed clamp held by the left hand. The right hand is inserted immediately into the hole to grasp the legs/feet, and the infant is delivered as for breech extraction with the help of fundal pressure by the assistant and before most of the amniotic fluid is drained. In case external podalic version fails, then internal podalic version is performed immediately after cutting the membranes. The importance of help by the assistant in turning and stabilizing the fetus during the process cannot be overemphasized, and the operator should brief the assistant thoroughly and provide the appropriate instructions at the right time. External cephalic version often does not work here, because the actual space within the uterine cavity is usually diminished due to decreased volume of the intrauterine fetal sac from the herniation through the uterine incision, even if the membranes remain intact. The author has encountered a number of occasions when the fetus remained stuck in transverse lie or developed compound presented when the membranes are cut following external cephalic version, as the fetal head is not low enough to act as a stopper to prevent most of the amniotic fluid from gushing out under pressure as soon as the membranes are cut.

Obstruction to delivery

Occasionally there is obstruction to delivery due to an extended limb, an umbilical cord that is extremely short thus causing the malpresentation or cord encirclement of the neck or limbs, or unsuspected submucosal fibroids. In case of difficulty in the delivery, a quick exploration of the fetal parts/posture and environment should be done, and the situation amended immediately by the appropriate manoeuvre. The cord may need to be clamped and cut before the infant can be delivered.

Delivery of the fetuses in multifetal pregnancy

Twins with cephalic/cephalic presentation

This is done as for singleton pregnancy with cephalic presentation, but the first twin to be delivered should be the one closer to the uterine incision, who is not necessarily the presenting twin by vaginal examination.

Twins with cephalic/breech presentation

The cepphalic-presenting twin should be delivered first, for locked twins can still occur if the breech-presenting twin is delivered first as there is no means of manipulating the breech-presenting twin if the head is obstructed by the body or head of the remaining twin. Under no circumstance should the sac of the remaining twin be cut in an attempt to free the stuck first twin, for this will only create more difficulty with the fetal parts of both twins entangled and locked together. If the breech-presenting twin is closer to the uterine incision if it is easy it should be pushed up and out of the way by the operator, and kept in place by the assistant, before the operator proceeds to deliver the cephalic-presenting twin.

Twins with breech/breech presentation

In this situation, the procedure is similar to that in delivering twins with cephalic–cephalic presentation, with the one closer to the incision to be delivered first. The second twin can be pushed out of the way until after the first twin is delivered.

Monoamniotic twins

The situation depends on the presentation and follows the aforementioned principles. The cord of the first twin may need to be clamped and divided before the infant is out of the uterus as the cords are often intertwined. Since there is only one sac, the amniotic fluid will be drained out quickly and there should be minimal delay in the delivery of the second twin.

Higher order multifetal pregnancy

Before the uterine incision is made, the fetuses should be carefully palpated to ascertain their lies and positions. Prior ultrasound assessment may not be helpful since the order of presentation relative to the uterine incision may not be the same as that at the time of the scan. Again, deliver the fetus closest to the uterine incision first. Then examine the remaining sacs to determine which fetus should be next. The sac closest to the incision should be the next fetus to be delivered and this is again facilitated by manipulating the remaining fetus(es) out of the way. This process is repeated until all the fetuses are delivered.

Delivery of the placenta

Cord traction following spontaneous separation

This is similar to the controlled cord traction following vaginal delivery.

Manual removal

This is similar to the manual removal method after vaginal delivery. Manual removal is associated with more operative blood loss, a greater drop in postoperative haemoglobin, and shorter operative time, but there is no difference in the incidence of endometritis, wound infection or need for blood transfusion.

Exploration of the uterus

After the delivery of the placenta, the uterine cavity should always be explored digitally to ensure that no placental tissue is left behind, especially in the case of marginal or velamentous insertion of the cord, or in multifetal pregnancy. If morbidly adherent placental tissue is encountered, treatment options depend on the site and size of the adherent tissue, the degree of bleeding, and uterine contraction. Small irregular fragments or a rough placental bed can be left alone if bleeding is minimal, especially if the uterus is contracting well. Large pieces of tissue, especially in the lower segment, have to be dealt with either locally by means of figure-of-eight sutures, or compression sutures with/without the addition of balloon tamponade (see relevant sections) after attempted removal of the bulk of the adherent tissue. Overzealous digital evacuation of adherent tissue, especially at the sites of scars of previous surgery, should be avoided since it may result in accidental perforation, or attenuation of the wall leaving only the serosa.

Repair of the uterus

• Uncomplicated lower segment incision: traditionally the lower segment incision is closed in two layers with absorbable synthetic sutures after the angles of the incision are first secured. The first layer should be a continuous non-locking suture involving at least two-thirds of the thickness of the myometrium from the decidual side but including as little decidua as possible. This layer of suture should be able to stop bleeding from myometrial vessels into the uterine cavity, the diagnosis of which may be delayed until the time of the vaginal examination after the operation. The second layer should be a continuous imbricating suture that includes the rest of the myometrium up to the serosa level, with the aim of proper closure of the incision and assurance of haemostasis, especially of the vessels that develop around previous uterine incision scars. A single layer closure should be reserved for totally uncomplicated cases or in the context of trials.

• Classical incision: a three-layer closure is preferred. The first layer should be interrupted stay sutures that include the angles and are placed about 1–1.5 cm apart, involving the inner half of the myometrial layer, and which is used to hold together the cut edges of the uterus. These are left untied until after the second continuous layer is inserted, which involves most of the myometrial layer. The first layer is sutured with the help of pressure from both sides provided by the assistant. The suture of the second layer is then tightened to take up the slack as the uterus usually has contracted somewhat by this time so that the second layer suture will be lax. The second layer is tied at both ends to achieve haemostasis. The third layer is a continuous imbricating suture that closes the remaining myometrium and serosa for final haemostasis.

• Tears in the upper or lower flap: a two-layer closure with continuous sutures is recommended. The apex of the tear must be identified and secured before most of the thickness of the tear is closed with the first layer. The second layer ensures proper closure and complete haemostasis. The repair should not extend into the incision proper or it can lead to distortion and impaired healing of the incision.

• Tears at the angles: it is important to stop any bleeding with haemostatic clamps first and then inspect the tear and the neighbouring structures, especially looking out for the ureters, before repair. Sharp dissection to mobilise the ureter out of harms way may be necessary. The tear should be repaired by figure-of-eight sutures placed at the exact site, and avoid over-repair with excessive sutures or including too much neighbouring tissue, as tying of the suture may pull the neighbouring tissue together and lead to kinking of the ureter and obstruction.

• Placental bed: bleeding vessels from the placental site can be tackled by figure-of-eight sutures, especially in the case of placenta praevia. Failure to achieve haemostasis may result in uncontrollable postpartum haemorrhage necessitating hysterectomy or uterine artery embolization.

Caesarean myomectomy

The traditional teaching is against myomectomy at the time of CS. However, myomectomy may be necessary because the fibroid(s) may cause significant distortion of the uterus and/or the uterine incision so that closure becomes difficult or that the union would not be expected to be satisfactory. Fibroids may also produce a ball-valve effect causing obstruction to the discharge of lochia, or interfere with uterine contraction resulting in persistent haemorrhage. Apart from anecdotal cases, a retrospective case–control study of 47 pregnancies with Caesarean myomectomy compared with 94 pregnancies without removal of the fibroids demonstrated that there was no need for hysterectomy, and no difference in the puerperal complications, postoperative haemoglobin, need for transfusion, or prolonged hospitalization in the myomectomy group, despite the fact that the myoma diameter in this group was significantly larger (7.9 cm versus 5.9 cm), and that 22.0% and 29.5% of the removed myomas were multiple and intramural/submucosal respectively.

EXIT procedure

The ex utero intrapartum treatment (EXIT) procedure was designed to ensure continuous oxygen supply through the placenta to a fetus who is having airway obstruction from congenital or iatrogenic causes, for which treatment in the form of establishing a patent and adequate airway for subsequent breathing has to be initiated during the time of birth and before separation of the placenta. This involves an elective delivery by CS with the appropriate teams standing by for immediate surgical treatment of the fetus as soon as the fetal head and part of the upper trunk are delivered outside the uterus. The mother has to be put under deep inhalational anaesthesia with/without concomitant tocolytic treatment to maintain total uterine relaxation until a patent airway is established in the fetus, who is then delivered and transferred to the receiving neonatal surgical team for further management. For the mother, the CS is completed as usual. The main maternal risk is bleeding from the hysterotomy.

Inspection of pelvic organs

After closure of the uterus a systematic and careful inspection of the pelvic organs, especially the bladder, should be performed before closure of the abdomen. It is not unknown that accidental cystotomy is discovered only at this stage. High-risk situations include previous CS or pelvic surgery, and pelvic/bowel/omental adhesions from any cause found at the time of surgery. Injury to the ureters may also occur especially if there is an extension of one of the angles of the incision or following repair of a haematoma. The tubes and ovaries must be inspected, in case an ovarian cyst/tumour is missed during pregnancy. Any ovarian tumours, especially solid tumours, found at CS should be removed for histological examination. If malignancy is suspected, frozen section should be arranged immediately and the oncologist be consulted for a proper assessment, staging, and further surgery if necessary.

Repair of the bladder/omentum/bowel

In case injuries to these organs are found, a proper assessment by an experienced surgeon is mandatory. Bleeding from omental vessels can be persistent and troublesome. Repair should be carried out only by an experienced surgeon, and a general surgeon should be consulted if necessary.

Postpartum management

Postpartum urinary retention, defined as a post-void residual bladder volume of ≥150 mL on ultrasound scan, can be as high as 24%, and the incidence of overt and covert retention were 7.45 and 16.7% respectively. The associated factors include morphine-related analgesia, multiple pregnancy and low BMI. Further reading

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www.babycenter.com

www.childbirth.org

www.netdoctor.co.uk Patient information and contacts

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www.babycenter.com

www.questia.com

www.pregnancy-info.net

Forceps delivery Definition

This refers to a form of operative vaginal delivery by means of an instrument called the obstetric forceps. The forceps are made with metal and consist of two halves (left and right). Upon assembly they produce a cradle for the fetal head, and upon traction along the handle that is connected by a shank to the cradle, will result in the controlled delivery of the fetal head, to be followed by the rest of the infant. Epidemiology

There has been a declining rate of forceps delivery in many centres due to a combination of factors that include the perceived higher maternal and fetal risks with forceps delivery, an increasing popularity with ventouse delivery, and the progressive loss of skills in forceps delivery. The rate of forceps delivery can be as low as mortality, intracranial and retinal haemorrhage, and feeding difficulty, were comparable between forceps and ventouse delivery, but forceps delivery is more likely to be associated with birth injuries, neonatal seizures, and need for assisted ventilation, but less likely to have shoulder dystocia. Clinical approach

Prerequisites for forceps delivery

In deciding for forceps delivery, the first consideration should be the skill and experience of the operator. Forceps delivery should be considered a surgical procedure and as such, it should be organized similarly with an operator, an assistant, a circulating nurse, a trained person for neonatal resuscitation, appropriate analgesia, the patient should have an intravenous drip or at least an intravenous access, and an aseptically prepared delivery trolley with a specially designated prepacked set of instruments. If the operator is inexperienced, the assistant should be the well experienced supervisor. The circulating nurse should be able to provide any additional equipment, administer medications, and to summon help where necessary. The person for neonatal resuscitation should be adequately trained to handle an infant born in a poor condition. For a patient receiving epidural analgesia, top up will be required if the effect is wearing off, or regional analgesia should be given if forceps delivery is planned beforehand. In case of emergency situation, adequate local anaesthetic should be infiltrated into the perineum in anticipation of an episiotomy. Nowadays, bilateral pudendal block is rarely given and if this is deemed necessary, regional analgesia may be preferable. Under normal circumstances, consent for the possible use of forceps delivery should have been obtained at an early stage, together with the consent for an episiotomy. In case this is not yet done, or the patient raises concerns, written consent may be preferable unless the decision is made urgently to avoid major compromise to the fetus.

The prerequisites for forceps delivery

• The fetal head must be engaged

• The cervix must be fully dilated

• The position of the head must be ascertained

• The shape of the pelvis should be assessed, and the adequacy of the outlet determined, making sure that the pelvis is not convergent

• The bladder should be empty

• The analgesia is effective

• The delivery team is ready and standing by.

Examination prior to the application of forceps

Abdominal palpation

Irrespective of the entries in the notes or partogram, the operator must perform a complete examination, starting with the abdominal examination. The operator should determine

• the amount of fetal head palpable above the pelvic brim in fifths (none or 0/5 should be palpable)

• the position of the anterior shoulder (this helps the subsequent manual rotation if necessary and reduces the risk of shoulder dystocia due to misdiagnosis of restitution and external rotation of the fetal head)

• whether the bladder is distended

• that the fetal size is not too large.

Only when these points are satisfied should forceps delivery proceed. In case of doubt, a trial of forceps can be organized in the operating theatre. In case more than one of these points are not satisfied, one should consider abandoning the procedure, since there are much greater risks of fetal hypoxia and injury, and maternal trauma, if forceps delivery fails and a caesarean section was required.

Vaginal examination

An aseptic approach should be adopted. If the bladder is still palpable, or it is uncertain if the bladder is empty enough, the bladder should be drained with a disposable catheter which is removed afterwards. Do not use a self-retaining Foley catheter as the balloon can be dragged along by the descending fetal head leading to forceful dilation and damage to the bladder neck and urethra, resulting in complete urine incontinence. Then perform the vaginal examination to determine

• full dilatation of cervix

• station

• position

• flexion

• asynclitism

• caput and moulding of the fetal head

• the shape and size of the bony pelvis and whether the pelvis is convergent.

Forceps delivery should not be performed if station is above the ischial spines in the absence of moulding, three-plus moulding despite a station of 1–2 cm below the ischial spines, a grossly deflexed or asynclitic head, and a convergent pelvis with an outlet that cannot admit the clenched fist of the operator. In case of doubt, the procedure should be organized in the operating theatre as a trial of forceps.

The choice of forceps

This should be dependent on the type of application and the findings on vaginal examination, and the experience that the operator possesses for different types of forceps. For outlet or lift-out forceps delivery, either Wrigley’s or Simpson’s forceps can be used. However, with the marked pelvic curve in Wrigley’s forceps, its application should be restricted to direct, or almost direct occipital anterior position, with or without manual rotation. Simpson’s forceps have minimal pelvic curve, and so it can be applied for both occipital anterior and posterior positions. For low cavity forceps, Neville-Barnes forceps is preferred, because the very short shank in Wrigley’s and Simpson’s forceps means that after application, the entire shank and even part of the handle may have gone inside the vagina, thus rendering traction difficult. Piper’s forceps are reserved for delivery of the aftercoming head of the breech. The long curved shanks ensure that after application of the blades, the handle is still beyond the level of the buttocks so that the trunk of the baby will not interfere with the operator as long as it is supported by the assistant. As well, the wide gap between the shanks ensures that the umbilical cord, dangling below the baby’s abdomen, will not be crushed by the shanks upon locking.

Kielland’s forceps belong to a category by itself. There is a slight backward pelvic curve, long overlapping shanks with a sliding lock, and on each anterior surface of the finger guard at the front of the handle of each side is a knob that denotes the anterior surface and serves as reference point for the occiput. The sliding lock allows the correction of asynclitism.

Always check the number imprinted on the handle of the forceps to ensure the two blades belong to the same pair, and then assemble the forceps to ensure that the pelvic and cephalic curves are symmetrical and the shanks can come together to lock, before application. In case of doubt, exchange for another pair of forceps. There should never be more than one pair of the same type of forceps on the delivery trolley in case of a mix-up of the blades. When ready the blades are liberally lubricated with KY jelly or Hibitane cream, then assembled again and placed on the trolley ready for use.

The application of forceps for traction in cephalic presentation

When ready for application, the pair of forceps is held with the right hand and the handles and shanks are disassembled with the left hand, which is then used to grasp the handle of the left blade. The forceps blades should be applied with the head in the occipital anterior (OA) position. Heads not in the OA position can be rotated manually. Manual rotation usually involves an initial upward motion to disimpact the head before rotation to as direct OA as possible, meanwhile avoiding deflexion and asynclitism. The head is then held in place with the same hand involved in rotation while the other hand is used to apply the first (left) blade. In this manoeuvre, ensure that the umbilical cord does not slip down or past the fetal head to be compressed by the fetal head later.

The first blade to be applied is the left blade. For forceps with a pelvic curve, the handle should be held with the end pointing skyward and lying in the palm of the left hand, the shank positioned above the maternal right groin and parallel to the right inguinal ligament, and the tip of the blade resting on the palm of the right hand the fingers of which are inside the vagina steadying the fetal head (especially after rotation). The first blade should be inserted after a uterine contraction, and never at the onset or height of a uterine contraction. With a gentle sweeping motion, the left hand describes an arc through the air, pushing the tip of the blade along the inside of the right hand which is used to retract away the vaginal wall and to assist the blade to negotiate the cephalic and pelvic curve. If a left mediolateral episiotomy has been made beforehand for whatever reason, the dorsum of the right hand forms a shield before the opened vaginal wall prevent the blade to cause further extension of or splitting up the wound further.

When the tip of the blade reaches the level of the proximal interphalangeal joints of the fingers, the fingers should bend with the finger tips pushing the fetal head medially thus creating room for the blade to advance. When the tip of the blade reaches the tip of the fingers, the fingertip of the index finger should slip into the fenestrum of the blade to maintain the pressure on the fetal head, while the tip of the blade should remain pressed against the tip of the middle finger. Then the fingers of the right hand are used to properly position the blade alongside the fetal head, advancing with the middle and ring fingers as the leading point and guiding the tip of the blade until the blade is in place. The index finger is used not only to create room but also to feel for the facial structures and the ear to ensure the correct positioning of the blade.

This approach will ensure the correct application of the blade and minimize both maternal and fetal trauma. If the fetal head rotates, descends or ascends, the movements will be detected by the index fingers, and the hand can make fine adjustments to allow the blade to be properly applied against the face without excessive force or pressure which can cause injuries. The feeling for the ear can also confirm the position and proper application of the first blade. Only when the blade is in place should the right hand withdraw slowly, with the left hand maintaining the position of the handle in the correct position. In case the baby is small or the pelvis very roomy, the mother can be asked too bear down slightly so that the downward pressure will keep the blade in place as the right hand withdraws as if it is squeezed out by the maternal effort, while the application of the fetal head against the cephalic curve of the blade will help to maintain its position.

With the left blade now in place and kept in position with the left hand with/without some maternal bearing down effort, the right blade is then applied using the same method, only with the sides reversed. The operator’s left hand is inserted into the vagina and the right blade is inserted in between contractions, i.e. the process is a repetition of the other side.

Once the right blade is in place, the shanks and handles should be almost alongside, and slight adjustment of one or the other side should allow the handle to lock. If the handles are not in alignment, the side that is at an angle should be brought into alignment gently by shifting the entire side anteriorly or posteriorly alongside the fetal head, and pushing upwards and then the handles are likely to lock. The operator must not forcibly move the malaligned handle into apposition with the other handle as this will not work and could cause trauma at the point of the base of the blade which becomes the fulcrum of such movements. Exerting pressure on the underlying fetal skull could result in a depressed fracture. If the shanks and handles are parallel but at different levels, the handle at the lower level should be gently pushed upwards, moving slightly anteroposteriorly as necessary, to bring the handles together and lock. Correct application is confirmed when the sagittal suture is perpendicular to the shanks and the posterior fontanelle is 3 cm above the plane of the shanks and only one finger can be admitted between the blade and the head on either side. When these conditions are satisfied traction can commence.

In case the handles cannot be locked together, the right blade should be retrieved for reapplication. Sometimes even the left blade may need to be reapplied, and in this instance, the fetal head usually would have changed its position so that the complete process of assessment and application has to be repeated again. If the forceps fail to lock a second time, the operator should suspect the following conditions: incorrect diagnosis of position, asynclitism, or failure to diagnose cephalopelvic disproportion. If difficulties are encountered with correct application, the procedure should be abandoned and a Caesarean section should be performed.

Traction for cephalic presentation

Traction should be gentle and along the axis of the birth canal, using both hands. The hand that is holding onto the handle exerts horizontal traction force, while the other hand is placed on the shanks before the first hand and exerts vertical downward force. Traction should be synchronized with uterine contractions and maternal bearing down efforts. Traction can be applied with the operator standing or sitting. Although the sitting position is preferred by many, one study demonstrated that more traction force is generated in the sitting position, so that this should be borne in mind during the procedure.

An episiotomy can be made, if it is felt to be necessary, at the time when the head is about to crown. As the head crowns, the other hand can be removed from the shanks. Traction should be maintained at a reduced level and the direction of pull should be guided by the degree of movement of the crowning head to become progressively upwards. In this way, the direction of traction is dictated by the direction of the path of least resistance, and inappropriately excessive horizontal traction, which may pull the occiput against the inferior pubic rami, or inappropriately excessive downward force, which may result in overstretching and tearing of the perineum, can both be avoided.

The head is delivered, controlling the rate so that it does not pop out. Once the jaws can be reached, the blades are first loosened by relaxing the grip on the handles, and then removed in the opposite order to application. Pushing the perineum below the emerging head will help a smooth controlled delivery of the head. Do not pull on the head excessively or too rapidly, as this will pull the shoulders, especially the anterior shoulder, to become impacted against the pubic bones thus creating iatrogenic shoulder dystocia. Once the head is delivered, allow time for restitution of the head so that the true position of the shoulders can be gauged. Then allow time for external rotation of the head which signifies engagement of the shoulders, before delivery of the anterior shoulder is attempted. Undue haste in delivery of the shoulders is the main reason for shoulder dystocia and brachial plexus injury in an otherwise normal sized baby through an adequate pelvis.

During delivery of the head and the shoulders, an assistant should guard the perineum to prevent sudden and excessive stretching along the episiotomy which could result in a third or fourth degree tear.

The application of forceps for rotation and traction in cephalic presentation

Kielland’s forceps are rarely used nowadays, as the indications are very limited and there has been much publicity about the associated maternal and fetal risks. If midcavity traction or rotation is required, ventouse delivery is usually preferred due to its higher safety margin and technical ease in its performance. The method of application of Kielland’s forceps is not covered in this chapter.

The application of forceps for the aftercoming head in breech delivery

Piper’s forceps is designed for the delivery of the aftercoming head in breech delivery. Following the delivery of the shoulders and arms, the fetal back is rotated to face upwards with the chin posterior, which can be confirmed by digital examination. An assistant supports the trunk and the limbs of the baby with a towel sling held by the assistant. The trunk should not be pulled upwards out of the way in order to avoid injury to the neck. The left blade is applied first with the operator in a sitting or kneeling position so that his/her vision is in line with the perineum and not obscured by the baby’s trunk. This is facilitated by the assistant carrying the baby’s trunk to the mother’s right horizontally. The left blade is applied, as described before, to the right side of the baby’s face, its position adjusted if necessary to allow for the slight variation of the position of the baby’s occiput. If resistance is encountered, the tip of the blade is introduced more posteriorly and then wandered around to the side of the head. The right blade is then applied in a similar manner. After locking the shanks the baby is allowed to straddle the forceps, with the handles held in the upturned palm of the right hand and the middle finger inserted in the space between the shanks.

Downward traction is made with the operator in the same position until the chin appears at the outlet. The handles are then elevated with traction, following the pelvic curve to bring the suboccipital region under the pubic arch. This is facilitated by using the index and middle fingers of the left hand to press on the suboccipital region, which also serves to protect the neck with the splinting effect. If resistance is encountered, the handles are depressed and then elevated again during gentle traction. Extraction of the head is achieved by maintaining the handles close to the horizontal and the blades in place. During delivery of the head, the occiput serves as the fulcrum for flexion. As the head is delivered, the assistant can hold the baby while the operator removes the blades from the baby’s head. The cord is clamped and divided and the baby is transferred to the resuscitaire.

Trial of forceps

In case of suspected cephalopelvic disproportion, or unfavourable pelvis, the forceps delivery should be organized as a trial of forceps. The anaesthetist should be alerted and the operating theatre prepared as for an emergency Caesarean section with the scrub and circulating nurses standing by. Blood should be sent for group and save. An intravenous drip should be set up and adequate regional analgesia be ensured. The woman should be prepared as for emergency general anaesthesia with ranitidine and sodium citrate given orally beforehand. The procedure is performed on the operating table with the woman in lithotomy position

Following application of the forceps, the three-pull rule (= over three contractions) should be strictly followed. The trial must be abandoned if delivery has not occurred, or is not imminent, and there is unsatisfactory descent by the third pull. The delivery should be converted to an emergency Caesarean section.

Procedures after successful delivery

Following each delivery, the following should be checked in addition to the routine examination:

• any extension of the episiotomy, vaginal and perineal tears, and third and fourth degree perineal tears

• cervical lacerations

• bleeding from above the cervix (this could be due to uterine lower segment tears or uterine rupture).

Vaginal and perineal tears, and episiotomy should be dealt with as described in the relevant chapters.

The baby should be resuscitated if necessary by a paediatrician. In case the forceps delivery is performed for fetal reasons, paired umbilical cord artery and venous blood should be taken for measurement of pH and blood gases. The placenta and membranes should be checked. In case of vulval perineal oedema or haematoma, an indwelling Foley catheter should be inserted for continuous drainage. The woman should be re-examined 1 hour later for evidence of vulvovaginal haematoma before she is transferred to the postnatal ward.

The indications, type of procedure, time and duration, and outcome of the delivery should be clearly documented in the notes. Any maternal and neonatal injuries must be recorded and where necessary diagrams can be drawn to indicate the site and extent of the injuries. The mother should have a clear picture of what has happened, since misunderstanding or misinformation, especially if injuries are present, can become the basis of future litigation.

Abandoning delivery (‘failed forceps’)

Forceps delivery should be considered unsuccessful under the following circumstances:

• if the blades could not be applied or locked

• if there was no progress after three pulls. Further reading

Demissie K, Rhoads GG, Smulian JC, et al. Operative vaginal delivery and neonatal and infant adverse outcomes: population based retrospective analysis. BMJ 2004; 329: 1-6.

Dennen PC. Dennen’s forceps deliveries, 3rd edn. Philadelphia: F.A. Davis 1989.

Johanson RB, Menon V. Vacuum extraction versus forceps for assisted vaginal delivery. Cochrane Database Syst Rev 1998; 4: CD000224.

Leslie KK, Dipasquale-Lehnerz P, Smith M. Obstetric forceps training using visual feedback and the isometric strength testing unit. Obstet Gynecol 2005;105:377–82.

MacArthur C, Glazener C, Lancashire R, et al. Faecal incontinence and mode of first and subsequent delivery: a six-year longitudinal study. Br J Obstet Gynaecol 2005;112:1075–82.

Patel RR, Murphy DJ. Forceps delivery in modern obstetric practice. BMJ 2004;328:1302–5.

Royal College of Obstetricians and Gynaecologists (RCOG) Operative vaginal delivery. Guideline No. 26. London: RCOG 2005. Useful websites

www.emedicine.com Patient resources

www.rcog.org.hk

Uterine compression sutures

Uterine compression sutures are sutures applied externally to the body of the uterus in various patterns and involving either the upper or lower segments or both, so as to act as a brace to facilitate uterine contraction and retraction. The tightening of the sutures also produces a compression effect. Together these two actions will help to control postpartum haemorrhage from the uterus, and possibly avoiding the need for hysterectomy as a life-saving procedure. Epidemiology

The actual incidence of the use of this treatment in the management of postpartum haemorrhage remains unknown. There are only anecdotal case reports and small case series in the literature and most likely represent under-reporting. In the experience of one centre, compression sutures were performed in 1 per 1126 deliveries over a 7-year period. All were carried out at Caesarean delivery, with an incidence of 1 in 221 Caesarean deliveries in labour and 1 in 637 elective Caesarean deliveries. Pathology

In cases of normal placentation, uncontrolled haemorrhage from the placental bed can occur due to a failure of occlusion of the placental bed blood vessels by the contracting myometrium if uterine atony develops. In cases of abnormal placentation, such as placenta accreta/increta, retained adherent placental tissue interferes with haemostasis in the placental bed, and the additional effect of uterine atony, whether as a primary or secondary event, would aggravate the situation. Therefore, correcting uterine atony and promoting uterine contraction play key roles in controlling postpartum haemorrhage. The myometrial response to uterotonic agents is quite variable, but it can be enhanced by external compression of the uterus. Hence, manual compression and massaging the uterus is effective in some cases. When this approach fails, the application of compression sutures may be considered, as this can reduce the uterine size and provide sustained compression force.

Compression sutures can be used in almost any form of postpartum haemorrhage, either as the primary surgical treatment or in conjunction with balloon tamponade. In postpartum haemorrhage in which inadequate uterine contraction and retraction is a significant factor, compression sutures result in direct occlusion of intramyometrial vessels, in addition to providing a scaffolding to facilitate the uterus to contract under the stimulation of uterotonics. For bleeding from placental bed vessels in the case of placenta praevia, and from the ragged placental bed in the case of placenta accreta, compression sutures applied externally over the bleeding site can also control the bleeding by similar mechanisms. Any residual bleeding can then be controlled by means of balloon tamponade. Aetiology

After delivery of the fetus and placenta, immediate haemostasis is achieved by occlusion of the arcuate and spiral arteries of the placental bed by means of contraction of the myometrial fibres in the uterine body. Hence, bleeding from the placental bed in the case of placenta praevia and abruption is less easily or well controlled. Direct application of haemostatic figure-of-eight or other forms of sutures is often successful, but on occasions, more extensive application of sutures to compress the vascular supply of the bleeding site is necessary. The variety of compression sutures reported in the literature can be applied to deal with bleeding from an atonic uterus to bleeding from localized sites in an otherwise well-contracted uterus.

The indications for compression sutures include

• uterine atony

• placenta praevia

• abnormal placentation, such as placenta accreta, increta and percreta. Prognosis

As absorbable suture material is used there is no risk of the threads causing long-term problems. However, there are several potential complications.

The first is avascular necrosis, usually involving partial thickness, of the uterine wall. The second is the problem of using non-absorbable sutures that become loose in the abdomen after the uterus has involuted. The third is the slipping of the sutures after application, causing problems such as bowel obstruction and strangulation of pelvic organs by cutting off the blood supply to the tissue/organs trapped within the loose loops. For absorbable sutures, there is no long-term problem to the uterus or pelvic organs as these would disappear eventually. Successful pregnancy has been reported following the application of compression sutures to control postpartum haemorrhage.

For the B-Lynch suture, more than 1300 cases have been performed with very few reported failures, which have been attributed to delayed application, defibrination syndrome, and technical problems. Among the handful of reported cases with postoperative imaging studies or follow-up assessment, no defects were found inside the uterine cavity, and suture erosion through the uterus was reported once. Successful pregnancies resulting in term deliveries have been reported in a number of reports.

For the square suture first described by Cho et al. (2000), uterine drainage and involution may be affected, and blood-filled pockets may result, although ultrasound imaging in one case reported patency of the uterine canal 2 weeks after surgery. Delayed complications include pyometra and uterine synechiae with partial obstruction of menstrual flow. Four subsequent pregnancies occurred in the original series of 23 cases. Partial thickness necrosis of the uterine wall has been reported in a case following combined B-Lynch and Cho-square sutures.

Information on the long-term morbidity and outcome, including menstrual and fertility issues, of the other techniques is scanty. Clinical approach

The use of uterine compression sutures should be considered when there is major postpartum haemorrhage, defined as estimated blood loss in excess of 1000 mL or more. Rather than as a last resort, this procedure should be considered whenever the uterus has to be conserved and conservative/medical methods are unsuccessful, especially following Caesarean delivery for placenta praevia, when the abdomen is already opened. In case of vaginal delivery, balloon tamponade can be tried first, followed by compression sutures if the former has failed. Compression suture can be combined with balloon tamponade, producing the uterine ‘sandwich’. A number of compression sutures have been reported in the literature. These are described below.

B-Lynch suture

First described by C. Balogun-Lynch, the B-Lynch suture is the most frequently reported, and probably the most widely applied, compression suture technique worldwide. The technique is described below.

Testing for efficacy

With the patient in the semi-lithotomy position, an assistant, standing between the patient’s legs, swabs the vagina to determine the extent of the bleeding. The operator then exteriorizes the uterus and applies bimanual compression of the whole uterus down to the level of the cervix. If the bleeding is stopped, then the suture has a good chance of successfully arresting the haemorrhage.

Suture application following Caesarean delivery

With an second assistant maintaining the bimanual compression, the operator displaces the bladder inferiorly and the first stitch is inserted 3 cm below the lower margin of the lower segment uterine incision on the patient’s left side, then threaded through the uterine cavity to emerge 3 cm above the upper uterine incision margin and approximately 4 cm from the lateral border of the uterus. The suture is then brought over the fundus vertically to the posterior side, maintaining the same 4 cm distance from the lateral border, and the needle is reinserted at the level of insertion of the uterosacral ligament into the uterine cavity. The needle is then brought horizontally across the cavity to the other side of the posterior uterine wall, exiting the cavity through the wall, thus bringing the suture outside the posterior wall. The suture is again brought over the fundus onto the anterior right side of the uterus. The needle then enters and exits the anterior wall at the corresponding points on the right side. During this process, the assistant maintains the compression as the suture is applied to ensure progressive and uniform tension to be applied as the suture compresses the uterus, and to avoid slippage. The ends of the suture are placed under tension and tied with a double throw after the lower segment incision is closed to ensure that the corners of the incision are secured and included in the repair of the incision without leaving any bleeding points. The first assistant then confirms that vaginal bleeding is controlled and then abdomen is closed.

Suture application following vaginal delivery

A hysterotomy is recommended to ensure that the uterine cavity is empty, exclude abnormal placentation, and remove large blood clots. The uterine incision also provides the anatomical landmark for the correct application of the suture and to ensure maximum and even distribution of the compression, without the risk of accidentally obliterating the lumen. In case of placenta accrete, increta, or percreta, an additional figure-of-eight or transverse compression suture can be applied to the bleeding site before the application of the longitudinal suture.

Suture material

A monocryl suture is recommended because it is user and tissue friendly with uniform tension distribution and is easy to handle.

Square suture

First described by Cho et al. (2000), this involves the placement of multiple full thickness square sutures applied with a straight number 7 or number 8 needle to approximate the anterior and posterior uterine walls, especially in areas with heavy bleeding, and achieving haemostasis by compressing the haemorrhagic site. The original report involved the use of chromic ‘1’ catgut. It was successful in all the 23 cases that were delivered by Caesarean section.

Vertical suture

There are some variations to this method of suturing.

• In Hayman’s technique, the primary vertical compression sutures are applied in a similar fashion to the B-Lynch technique except that the left and right side are placed separately without the need to open up the uterine cavity, and the knots are tied over the fundus. Horizontal cervical isthmic sutures can be applied if necessary. Although quicker to perform, this method does not allow the uterine cavity to be explored.

• In the technique described by Nelson and Birch (2006), performed after a Caesarean section, a number ‘2’ vicryl suture threaded through a large needle was inserted 2 cm below the uterine incision in a similar manner to the B-Lynch technique, and then brought up vertically and exits the anterior wall 2 cm above the uterine incision. Then the suture was passed through the fundus 3–4 cm medial to the cornual region and 2–3 cm below the superior aspect of the fundus. The needle and suture are then brought back through the posterior aspect of the lower segment and joined anteriorly after exiting below the uterine incision. The process is repeated on the other side. The suture is tied while bimanual compression of the uterus is done by an assistant. The uterine incision is then closed after bleeding has been seen to be controlled.

• Another form of short vertical sutures described by Tjalma and Jacquemyn (2004) involves the placing of sutures 2 cm apart in rows of four, with the needle passing from the anterior through the posterior wall and then back to the anterior wall, exiting anterior wall about 1 cm medial to the point of initial entry; the thread is then tied.

• A variation of this approach used in a case of relaparatomy after Caesarean section for placenta praevia is reported by Muppala et al. (2006), in which four parallel vertical sutures were applied to the lower segment without reopening the uterine incision, using number ‘1’ vicryl suture mounted on a curved round bodied needle. The sutures were placed anteroposteriorly just above the attachment of the uterosacral ligaments, each being 1.5–2 cm apart, and the exit point is 2 cm cranial to the entry point in the anterior wall.

• A similar but modified procedure has been described by Hwu et al. (2006) in the management of bleeding from placenta praevia or accreta during Caesarean section. This involves two parallel vertical sutures that are placed 3 cm medial to the right and left borders of the lower segment respectively. The 40-mm curved round needle is inserted 2–3 cm above the upper margin of the cervix into the uterine cavity, then into the middle layer of the posterior wall of the lower segment 2–3 cm above the upper cervical margin. The needle then travels for 3–4 cm vertically upwards within the middle layer of the posterior wall and exits through the uterine cavity and anterior wall at a point 2–3 cm below the uterine incision. Each suture is tied individually as tightly as possible, and the uterine incision is closed in the usual manner.

U-suture

This was described by Hackethal et al. (2008), using a Vicryl ‘0’ suture and an XLH needle with the curve straightened manually. For an interrupted single U-suture, the needle is inserted at the anterior wall through to exit at the posterior wall, then passed back through the anterior wall forming a horizontal U that includes 2–4 cm of tissue, and the thread is joined by a flat double knot tied while the uterus is compressed bimanually by an assistant. The number of suture required depends on the size of the uterus and persistence of bleeding, and usually 6–16 U-sutures in horizontal rows starting from the fundus and ending at the cervix are required.

One variation of the U-suture is the isthmic-cervical apposition described by Das et al. (2005), which is applied only in the lower segment and essentially involves the two horizontal isthmic-cervical sutures of the Hayman technique.

Transverse suture

This was described by Ouahba et al. (2007) and involves four sutures. First an absorbable suture on a big round needle is inserted from the serosa of the anterior wall to the serosa of the posterior wall through the cavity of the uterus on one side in the lower segment. The needle is then brought to a point 8 cm across from the exit of the suture and inserted again from the posterior to the anterior wall on the other side. The ends of the suture are brought to the midpoint of the anterior wall and a flat double knot is tied as tightly as possible, thus forming a loop to compress the uterus. To facilitate the procedure, the uterine walls should be compressed to reduce the thickness and distance between the anterior and posterior walls. A second suture is placed likewise across the middle of the uterine body. The third and fourth sutures are placed 2–3 cm medially in the left and right horns. If bleeding continues, hysterectomy should be performed. This method was used to treat 20 women with postpartum haemorrhage due to uterine atony not responding to medical management, including 17 who had a Caesarean delivery. Hysterectomy was only required in one woman who had developed disseminated intravascular coagulopathy.

Postoperative management

This is along the lines of the management of postpartum haemorrhage using balloon tamponade. If balloon tamponade is used in conjunction, the balloon catheter is removed following the same protocol. If compression sutures alone are used, uterotonic agents should be maintained until bleeding is controlled for several hours, the duration of uterotonic infusion is dependent on the underlying cause(s) and the patient’s condition. The sequence of events and the procedure should be clearly documented in the clinical record, which should include a diagram describing the positions/sites of the applied sutures. This will facilitate explanation to the patient afterwards and the preparation of any medical report in the future.

Since absorbable sutures are used, there is no need to remove them at a later date. However, maternal vital signs and symptoms should be monitored for the rare complications such as pyometra. Postnatal follow-up should be more frequent, the first visit preferably at 2 weeks post-partum. There is no recommendation for routine ultrasound examination of the uterus and the uterine cavity in the postnatal period, but this should be arranged if there is any suggestion of complications or if the uterus fails to involute at the normal rate. Further reading

Akoury H, Sherman C. Uterine wall partial thickness necrosis following combined B-Lynch and Cho square sutures for the treatment of primary postpartum hemorrhage. J Obstet Gynaecol Can 2008;30:421–24.

Allam MS, B-Lynch C. The B-Lynch and other uterine compression suture techniques. Int J Gynecol Obstet 2005;89:236–41.

Balogun-Lynch C, Whitelaw N. The surgical management of post partum haemorrhage. Fetal Matern Med Rev 2006;17:105–23.

Baskett TF. Uterine compression sutures for postpartum hemorrhage. Efficacy, morbidity, and subsequent pregnancy. Obstet Gynecol 2007;110:68–71.

Chen C-P, Chang T-Y, Yeh L-F, et al. Sonographic appearance of the uterus after simple square suturing for rapid control of post-partum hemorrhage and preservation of fertility. J Clin Ultrasound 2002;30:189–91.

Cho JH, Jun HS, Lee CN. Hemostatic suturing technique for uterine bleeding during cesarean delivery. Obstet Gynecol 2000;96:129–31.

Das C, Mukherjee P, Choudhury N, et al. Isthmic-cervical apposition suture: an effective method to control postpartum hemorrhage during cesarean section for placenta previa. J Obstet Gynecol India 2005;55;322–4.

El-Hamamy E, B-Lynch C. A worldwide review of the use of the uterine compression suture techniques as alternative to hysterectomy in the management of severe postpartum haemorrhage. J Obstet Gynaecol 2005;25:143–9.

Habek D, Kulas T, Bobić-Vuković M, et al. Successful of the B-Lynch compression suture in the management of massive postpartum hemorrhage: case reports and review. Arch Gynecol Obstet 2006;273:307–9.

Hackethal A, Brueggmann D, Oehmke F, et al. Uterine compression U-sutures in primary postpartum hemorrhage after cesarean section: fertility preservation with a simple and effective technique. Hum Reprod 2008;23:74–9.

Hayman R, Arulkumaran S, Steer PJ, et al. Uterine compression sutures: Surgical management of postpartum haemorrhage. Obstet Gynecol. 2002;99:502–6

Hwu Y-M, Chen C-P, Su H-S, Su T-H. Parallel vertical compression sutures: a technique to control bleeding from placenta previa or accrete during cesarean section. Obstet Gynecol Surv 2006;61:82–3.

Muppala H, Basama FMS, Hamer F. Re-laparotomy and parallel vertical-compression sutures and prostaglandins for massive intraperitoneal haemorrhage following caesarean section for placenta praevia. Internet J Gynecol Obstet 2006;5(2).

Nelson GS, Birch C. Compression sutures for uterine atony and hemorrhage following cesarean delivery. Int J Gynecol Obstet 2006;92:248–50.

Nelson WL, O’Brien JM. The uterine sandwich for persistent uterine atony: combining the B-Lynch compression suture and an intrauterine Bakri balloon. Am J Obstet Gynecol 2007;196:9–10.

Ochoa M, Allaire AD, Stitely ML. Pyometra after hemostatic square suture technique. Obstet Gynecol 2002;99:506–9.

Ouahba J, Piketty M, Huel C, et al. Uterine compression sutures for postpartum bleeding with uterine atony. Br J Obstet Gynaecol 2007;114:619–22.

Tjalma WAA, Jacquemyn Y. A uterus-saving procedure for post-partum hemorrhage. Int J Gynecol Obstet 2004;86:396–7.

Wu H-H, Yeh G-P. Uterine cavity synechiae after hemostatic square suturing technique. Obstet Gynecol 2005; 105; 1176–8. Internet resources

www.obgmanagement.com Patient information and contacts

www.rcog.org.hk

Ventouse delivery Definition

Ventouse delivery refers to a form of operative vaginal delivery in which a cup-type device is applied to the fetal head and kept in place through the creation of a vacuum between the cup and scalp. Traction on the cup is then applied to bring about descent and rotation of the fetal head with the aim to assist the delivery of the fetal head, working in conjunction with uterine contractions and maternal bearing down effort. Epidemiology

Among most centres, the overall operative vaginal delivery rate is around 12–20%. There is a trend of increasing ventouse delivery and decreasing forceps delivery, with a ratio that varied from 2:1 to 5:1 or more between ventouse to forceps delivery, and the reported rate of ventouse delivery varied from 7% to 15%. Introduction

The ventouse device consists of a cup, made with either metal or plastic, and connected to a suction system through which vacuum suction can be generated by means of an electric or hand pump. The negative pressure generated within the cup sucks in the fetal scalp which will completely fill up the space within the cup by forming an artificial caput or chignon. It was originally thought that 10 minutes are required for an effective chignon to form, but it is now known that only 2 minutes are required. Traction may commence after 1 minute without compromising efficiency and safety. The recommended vacuum pressure is 80 kPa (600 mmHg). Traction on the cup can be exerted by means of a handle or a metallic chain connected to a handle, and this in turn pulls the fetal head along, eventually achieving delivery through the combined effects of uterine contractions and maternal expulsion efforts.

For the expulsive phase of vaginal birth, the forces acting on the fetal head has been estimated to be between 8 kg and 15 kg. Traction force of 10 kg or less has been shown to be sufficient for ventouse delivery without dislodgement of the cup.

For the infant, scalp laceration may occur along the rim of the cup or on the chignon within the cup if the cup is manipulated or rotated artificially, or if excessive traction force is exerted at an angle from the vertical axis of the cup, or if the cup becomes dislodged due to inappropriately exerted force or leakage in the system. Leakage can occur around the rim of the cup due to incorrect direction of traction, inappropriate manipulation, or accidental trapping of maternal tissue, and will result in failed traction or cup dislodgement. If the cup is incorrectly positioned over one of the fontanelles, the negative pressure may cause intracranial injuries and haemorrhage, especially if the cup becomes dislodged. There is no evidence that reducing the vacuum pressure between contractions or keeping the vacuum pressure to 45°), severe moulding, and maternal distress or exhaustion, weak infrequent contractions, and with the station being low or mid with the caput not visible. Other associated risk factors of neonatal injury include nulliparity, delivery requiring more than three pulls, and dislodgment of the cup. Indications

Ventouse delivery is performed for indications similar to those of forceps delivery except that midcavity rotation (autorotation) is largely performed with ventouse rather than forceps nowadays. Also, ventouse delivery can be attempted in very skilful hands for situations that are absolutely contraindicated for forceps delivery.

Indications for ventouse delivery

• Suspected fetal distress

• Suspected maternal distress/fatigue

• Lack of progress in the second stage of labour

• with epidural analgesia: ≥3 hours in nulliparas and ≥2 hours in multiparas

• without epidural analgesia: ≥2 hours in nulliparas and ≥1 hour in multiparas;

• Malposition in the absence of or minimal moulding and station below spines

• Delivery of the cephalic-presenting second twin (in this instance the procedure can be attempted even when the cervix may appear to have shrank, as long as the cup can be applied correctly without trapping any cervical tissue. A smaller sized metal cup, e.g. No. 4 may be preferred here).

Contraindications for ventouse delivery

• Cephalopelvic disproportion

• Brow, face or breech presentation

• Station at/above ischial spines and/or caput not visible at introitus (twin two is exception to this rule), and/or with 2-plus moulding, or station at 0 to 2 cm below spines but with 3-plus moulding

• Fetal position undetermined or uncertain

• Suspected or confirmed bleeding tendency or coagulation defect in the fetus

• Absence of or deficient maternal efforts/expulsive powers/cooperation,

• Incomplete cervical dilatation (twin two is exception to this rule, see above). Prognosis

In general ventouse delivery is associated with fewer maternal and neonatal traumatic injuries, but some studies nevertheless have reported more birth trauma associated with ventouse delivery. Compared with forceps delivery, ventouse delivery was associated with less general and regional anaesthesia, Caesarean delivery, and more vaginal deliveries. Neonatal cephalhaematoma and retinal haemorrhage are associated more with ventouse delivery. The failure rates of rigid and soft cups are 9% and 16% respectively, and the rates for dislodgement are 10% and 22% respectively. Soft cups are associated with less scalp injury, but there is no reduction in the risk of cephalhaematomas.

Possible injuries can be direct and indirect and can occur in both the mother and neonate in the same case.

Maternal injury

• Lacerations to the genital tract, including cervical, vaginal and perineal first and second degree tears. Even with an episiotomy, ventouse delivery may still be associated with radial tears in the vagina/perineum.

• Anal sphincter injury in the form of third- and fourth-degree tears.

• Cervical laceration.

Neonatal injury

• Injuries to the scalp and skull, including scalp blisters and lacerations, cephalhaematoma (as high as 10.8–11.5%), subaponeurotic haemorrhage, and skull fracture (5.0%).

• Intracranial injuries, including retinal haemorrhage, subdural haematoma, subarachnoid haemorrhage, and tentorial tear; intracranial haemorrhage can occur in up to 0.87%.

• Brachial plexus injury, can be associated with shoulder dystocia following ventouse delivery. The risk was increased with the time required for ventouse extraction.

In singleton, neonatal deaths were associated with cranial trauma. Cranial traumatic injury was almost always associated with physical difficulty at delivery and the use of multiple instruments. The use of ventouse as the primary or only instrument did not prevent this outcome. Subaponeurotic (subgaleal) haematoma has been strongly related to delivery or attempted delivery by ventouse extraction. It has been shown that ventouse extraction was associated with increased risk of subarachnoid haemorrhage and cephalhaematoma compared with forceps delivery. However, it was also shown that while infants delivered by ventouse extraction had higher rate of subdural or cerebral haemorrhage compared with infants delivered spontaneously, there was no significant difference from that associated with forceps use. The common risk factor for haemorrhage was actually abnormal labour. Clinical approach

When operative delivery is indicated, the choice between ventouse and forceps delivery is related not only to the medical indications and contraindications, but to the status, experience, and perception of the operator as well. It has been shown that even among the same group of specialists with similar expertise, ventouse delivery tended to be used in less difficult cases in women with higher parity and shorter labour compared with forceps delivery. There are also different preferences in the choice of the ventouse cups.

Ventouse delivery is thought to be an easier and safer procedure with less risk of maternal and fetal injuries, in many centres. This method is used by family physicians as well, while forceps delivery is restricted to obstetricians. Appropriate level of skill is required to achieve the best outcome, and ventouse delivery should not be taken light-heartedly. In obtaining consent it is best to provide explanation for performing forceps and ventouse delivery, since forceps delivery may have to be used in case of failed ventouse delivery. Type of ventouse devices available

Soft anterior cups

• Silc cup

• Standard Mityvac cup

• Soft-touch cup

• Kiwi ProCup.

Rigid anterior cups

• Malmstrom cup

• Bird Anterior original (chain) cup

• Bird Anterior New Generation (string) cup

• O’Neil Anterior cup

• M-Style Mityvac cup

• Flex cup

• Kiwi OmniCup.

Posterior cups

• Bird Posterior original (chain) cup

• Bird Posterior New Generation (string) cup

• O’Neil Posterior cup

• Kiwi OmniCup

• M-select Mityvac cup.

Usually, only a few types of devices are available in any given hospital, and most obstetricians are familiar with only a few of these devices. It is recommended to focus on learning the use of and become proficient in one type each of the anterior and posterior cup before embarking on trying other cups. Some cups have an indicator (a knob in metallic cups) to show the position of the occiput. This allows tracking of the rotation of the occiput if the cup is correctly placed with the indicator in the direction of the occiput.

The prerequisites for ventouse delivery

Essentially this is a checklist to ensure that contraindications have been excluded.

• The fetus is in cephalic presentation and the fetal head is engaged.

• The fetus is at or near term and the estimated birth-weight is ≥2500 g.

• The exact position of the head should be ascertained.

• There are no fetal contraindications to the use of negative suction pressure on the fetal scalp, such as suspected bleeding tendency and thrombocytopenia.

• Uterine contractions are present, and if the contractions are weak and infrequent, then the uterus is responding to augmentation with oxytocin infusion.

• The mother is conscious and able to bear down spontaneously or following instructions if she is under the effect of epidural analgesia, and that there are no maternal contraindications to bearing down.

• The analgesia is effective.

• The cervix should be fully dilated, but in skilful hands, ventouse delivery can be performed with cervical dilation of 8–9 cm in multiparas.

• There is no obstruction or narrowing in the birth canal that could result in difficulties or failure of the procedure. The shape of the pelvis should be assessed, and the adequacy of the outlet determined, making sure that the pelvis is not convergent.

• The bladder should be empty.

• The delivery team is all ready and standing by, including a staff member (nurse/midwife, obstetrician, or neonatologist) assigned to resuscitate the neonate.

Examination prior to cup application

• Abdominal palpation: this should be performed as in the case of forceps delivery to determine the amount of fetal head palpable above the pelvic brim and the side of the fetal back. Similarly, in case of doubt, a trial of ventouse can be organised in the operating theatre. In case the findings on abdominal examination are non-reassuring, the operator should consider abandoning the procedure, since there are much greater risks of fetal hypoxia and injury, and maternal trauma, if ventouse delivery fails and forceps or caesarean delivery is required instead.

• Vaginal examination: again the same approaches to forceps delivery should be applied here. At times, the large caput or significant moulding may make the diagnosis of the position, or the degree of deflexion and asynclitism, difficult to ascertain. In this instance, a trial of ventouse delivery can still be performed.

The choice of the ventouse cup and instrument check

This should be dependent on the type of application and the findings on vaginal examination. For low-risk procedure, a soft or rigid cup can be chosen. For high-risk procedure, a rigid cup is preferable. For mid-cavity, or occipital posterior and transverse position, the posterior cup should be chosen. For metal cups, different sizes may be available, and for a normal size or large fetus, the No. 5 cup (5 cm diameter) should be chosen. Whatever the choice, always check the instruments, the connection, and the working of the pump before application.

The application of the ventouse cup

Location of the ‘flexion point’

In applying the ventouse cup, it is important to ascertain the flexion point, which is about 3 cm anterior to the posterior fontanelle on the sagittal suture. This point represents the leading end of the completely flexed and normally moulded head as it descends the birth canal. If the ventouse cup is properly placed over the flexion point and traction is applied, the fetal head diameters would be optimal for delivery with no need for any manoeuvring or manipulation of the fetal head through the point of traction.

Placement of the cup

The following process can be used to facilitate placement of the cup over the flexion point. During the vaginal examination, first locate the posterior fontanelle with the middle finger and then place the index finger about 3 cm from the middle finger along the sagittal suture. Then the middle finger is moved to join the index finger, the tip of the former now resting on the flexion point. The hand is supinated with the palm facing upwards. The index finger is then moved towards the palmar surface along the middle finger until the tip reaches the level of the posterior four-chette. The length of the middle finger as marked by the tip of the index finger represents the distance inside the vagina that the ventouse cup must be inserted to achieve a correct application. If in order to keep the finger tip on the flexion point the middle finger remains buried in the vagina up to the carpometacarpal joint, then the fetal head is too high for an attempted instrumental vagina delivery which should therefore be abandoned.

Building up the vacuum pressure

Once the cup is properly placed, the negative pressure can be built up to the recommended 80 kPa in one step, although the traditional teaching is to build this up stepwise over 3–6 minutes.

The traction for cephalic presentation

Number and duration of tractions

The traction force and number of pulls are influenced by all the factors that determine the success or otherwise of vaginal delivery. Therefore restricting the number of pulls to ‘three’ in the completion of the delivery process may not be practicable, especially in the presence of epidural analgesia and a restrictive approach to episiotomy. One study showed that only 27% of the deliveries were completed within three pulls. It is recommended to divide the process into a descent and an outlet phase. A higher traction force and greater number of pulls may be required for the outlet phase than is the case for the descent phase, and 84% of the deliveries were completed by three pulls each of the descent and outlet phase (six pulls in total) without increase in significant adverse outcomes. In terms of the time duration, most deliveries were completed in 15 minutes and almost all in 20 minutes. However, if progress is not observed in the first three pulls, the procedure should be abandoned even if the time duration is much less than 15 minutes.

Method of traction for occipital anterior position

Traction should be synchronized with uterine contraction and maternal bearing down efforts. The fingertips of the dominant hand should be used to hold onto the crossbar of the traction device, and the traction force, being limited by the fingertips, should be generated from the elbow and shoulder rather than from the whole body. The traction force exerted should be smooth and steady along the axis of the birth canal and not jerky or wagging sideways or up and down. By ensuring that the handle remains perpendicular to the outside of the cup, the direction of traction will be along the axis of the birth canal. The axis will change from downwards to horizontal. Only when the head crowns should the traction be directed upwards.

During traction the other hand should provide counter-traction with the thumb on the cup and the index finger is placed on the scalp to reflect the descent of the head. Counter-traction should be given until the head is delivered. Traction should stop once the uterine contraction is over and/or the mother stops bearing down. No difference in the time required for delivery, incidence of method failure, or maternal and neonatal complications, could be demonstrated between continuous traction to maintain fetal station with the same negative suction pressure versus intermittent traction with reduction in negative suction pressure between contractions.

As the head crowns, avoid pulling too hard or rapidly, because the resistance due to the resistance of the perineum can lead to dislodgement of the cup, and time should be allowed for the completion of autorotation. Episiotomy, if indicated, should be made at this point.

Traction for occipital posterior and transverse positions

The procedure is similar to traction for occipital anterior position, but the most important point is the correct placement of the posterior cup at the flexion point (flexing median application). Flexion of the head and anterior autorotation of the head occurs in >90% of the cases as long as there is flexing median application, whereas autorotation occurs in only 30% if the application is deflexing. There is no need to manipulate the cup or the handle in attempts to rotate the head, which could actually cause more failures (cup dislodgement).

Failed ventouse delivery

Failure can be in form of failure to descend with tractions or dislodgement of the cup. The commonest cause of failure is incorrect technique as 80% of the cases of failed ventouse delivery would have delivery completed with forceps. Other causes include persistent occipital posterior or transverse position, midcavity procedure, deflexing and paramedian application of the cup, use of inappropriate cup, traction before full cervical dilatation, and undiagnosed cephalopelvic disproportion. In the latter instance there is increased risk of fetal intracranial injury and laceration to the maternal genital tract.

Following failure of ventouse delivery, there should be a reappraisal of the likelihood of vaginal delivery. If the fetal head is visible at the introitus, forceps delivery may be attempted.

Trial of ventouse delivery

In case of suspected cephalopelvic disproportion, or unfavourable pelvis, the ventouse delivery should be organized as a trial of ventouse. The same preparations for a trial of forceps apply here. The same three-pull rule for initial progress is similarly followed, but progress is assessed not only in terms of descent but also of flexion and rotation of the head as reflected by the indicator on the cup. The trial must be abandoned if delivery has not occurred, or is not imminent, or there is no suggestion of flexion or rotation that should have occurred, by the third pull. The cup must be detached before the emergency Caesarean section is performed. If an episiotomy has been made already, this can be packed and repaired later after the baby has been delivered.

Procedures after successful delivery

Following ventouse delivery, the genital tract and perineum should be checked, and tears and episiotomy repaired, in the same way as following forceps delivery.

The baby should be resuscitated in the same way and documentation of neonatal acid–base status performed. A thorough examination of the neonate should be conducted to look for any injuries which, if present, should be clearly documented. The placenta and membranes should be checked to make sure it is complete. In case of vulval or perineal oedema or haematoma, an indwelling Foley catheter should be inserted for continuous drainage for the first 24 hours. The patient should be re-examined one hour later for evidence of vulvovaginal haematoma before being transferred back to the postnatal ward.

Training in ventouse delivery

Ventous delivery is often considered as an easy procedure. Emphasis on the proper and adequate training in its use is wanting. Ventouse delivery was shown to be associated with a relatively high failure rate, which was related in part to suboptimal application and inappropriate positioning of the cup. Apart from possible difficulty in the accurate application of the cup due to caput or malposition, poor assessment of the orientation and position of the fetal skull might also have played an important role, thus underscoring the need for improvement in training methods. Further reading

Bofill JA, Rust OA, Schorr SJ, et al. Morrison JC. A randomized trial of two vacuum extraction techniques. Obstet gynecol 1997;89:758–62.

Cargill YM, MacKinnon CJ. Guidelines for operative vaginal birth. SOGC Clinical Practice Guidelines. J Obstet Gynaecol Can 2004;26:747–53.

Chadwick LM, Pemberton PJ, Kurinczuk JJ. Neonatal subgaleal haematoma: associated risk factors, complications and outcome. J Paediatr Child Health 1996;32:228–32.

Chan CCT, Malathi I, Yeo GSH. Is the vacuum extractor really the instrument of first choice? Aust NZ J Obstet Gynaecol 1999;39:305–9.

Gilbert WM, Nesbitt TS, Danielsen B. Associated factors in 1611 cases of brachial plexus injury. Obstet gynecol 1999;93:536–40.

Johanson RB, Menon V. Vacuum extraction versus forceps for assisted vaginal delivery. Cochrane Database Syst Rev 2007; 4: CD000224.

Mollberg M, Hagberg H, Bager B, et al. Risk factors for obstetric brachial plexus palsy among neonates delivered by vacuum extraction. Obstet Gynecol 2005;106:913–18.

O’Mahony F, Settatree R, Platt C, Johanson R. Review of singleton fetal and neonatal deaths associated with cranial and cephalic delivery during a national intrapartum-related confidential enquiry. Br J Obstet Gynaecol 2005;112:619–26.

Simonson C, Barlow P, Dehennin, et al. Neonatal complications of vacuum-assisted delivery. Obstet Gynecol 2007;109:626–33.

Towner D, Castro MA, Eby-Wilkens E, Gilbert WM. Effect of mode of delivery in nulliparous women on neonatal intracranial injury. N Engl J Med 1999;341:1709–14.

Vacca A. Reducing the risks of a vacuum delivery. Fetal and Maternal medicine Review 2006: 17: 301–15.

Vacca A. Vacuum-assisted delivery. Baillieres Best Pract Res Clin Obstet 2002;16:17–30.

Wen SW, Liu S, Kramer MS, et al. Comparison of maternal and infant outcomes between vacuum extraction and forceps deliveries. Am J Epidemiol 2001;153:103–7. Internet resources

www.emedicine.com

www.aafp.org Patient resources

www.rcog.org.hk

Part 3 Gynaecology

Reproduction

Benign and urogynaecology

Benign, premalignant, and malignant tumours in gynaecology

Common gynaecological procedures and surgery