22 Surgical Disease and Trauma in Pregnancy

Emily S. Wu

Nancy A. Hueppchen

GENERAL CONSIDERATIONS

• One in 500 pregnant women will require nonobstetric surgery.

• The goals for diagnosis and management of surgical disease during pregnancy are to provide definitive treatment and to maintain a successful pregnancy.

• Diagnosis in pregnancy can be difficult due to the physiologic changes of pregnancy; presentation and symptoms may not be typical.

• Always consider and discuss the potential harm to the fetus for any intervention. Similarly, always consider and discuss the potential harm to the mother if intervention is delayed.

• Risks of nonobstetric surgery during pregnancy include preterm labor, preterm delivery, and fetal loss. Overall, there is a 9% risk of preterm delivery with surgery during pregnancy.

Anatomic and Physiologic Changes in Pregnancy

• The gravid uterus displaces abdominal organs cephalad and brings adnexal structures into the abdomen.

• Uterine compression of the inferior vena cava decreases venous return and may cause supine hypotension syndrome. Whenever possible, the pregnant patient should be placed in the left lateral decubitus position for surgery.

• Increased plasma volume, decreased hematocrit, and generally lower blood pressure make acute blood loss assessment more difficult.

• The hypoalbuminemia of pregnancy predisposes the patient to edema.

Diagnostic Radiology and the Pregnant Patient

• Pregnancy should not impede the use of necessary imaging studies for critical diagnoses.

• According to consensus statements from multiple professional organizations, the risk of malignancy, miscarriage, or major malformations is negligible in fetuses exposed to 5 rad or less. Potential effects of up to 10 rad are too subtle to be clinically detectable or distinguishable from the background risk. The risk is highest between 8 and 15 weeks' gestation.

• Iodinated radiographic contrast is rated category B in pregnancy, although it crosses the placenta and poses potential harm to the fetal thyroid, especially at 10 to 12 weeks of gestation. The American College of Obstetricians and Gynecologists recommends avoiding iodinated contrast in pregnancy; in cases where contrast imaging is required, ¹²³I or technetium 99m (pregnancy category C) should be used in place of ¹³¹I and the newborn should have thyroid function testing in the first week of life.

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TABLE 22-1 Estimated Conceptus Dose from Common Radiologic Procedures

CT, computed tomography; PE, pulmonary embolism.

Adapted from Wang PI, Chong ST, Kielar AZ, et al. Imaging of pregnant and lactating patients: part 1, evidence-based review and recommendations. AJR Am J Roentgenol 2012;198(4):778-784.

• Contrast agents iohexol, iopamidol, iothalamate, ioversol, ioxaglate, and metrizamide do not appear to be teratogenic. In lactating women, it should be safe to continue breast-feeding, but mothers may choose to discard breast milk for 24 hours.

• Gadolinium contrast may be associated with increased risk of pregnancy loss, skeletal abnormalities, and visceral abnormalities. It should be used during pregnancy with extreme caution with full discussion of its risks and benefits.

SURGICAL DISEASES IN PREGNANCY

• Pregnancy should not preclude any indicated surgery, regardless of trimester.

• Nonurgent surgery is ideally performed in the second trimester. Pelvic surgery during the first trimester carries increased risk of spontaneous abortion from disruption of the corpus luteum. Inadequate operative exposure and risk of preterm delivery complicate third-trimester surgery.

• Elective surgery is generally postponed until after delivery.

• Preoperative and postoperative fetal heart rate monitoring appropriate for gestational age is recommended.

• Intraoperative considerations include the following: positioning in left lateral decubitus, avoiding uterine

manipulation, optimizing maternal oxygenation, and avoiding wide variations of blood pressure.

• Intraoperative fetal heart rate monitoring is not routinely recommended but may be appropriate if the fetus is viable, electronic fetal monitoring is physically possible, interventions for fetal indications are available and consent is obtained, and potential interventions for fetal distress will not jeopardize the safety of the planned surgery.

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• At standard concentrations, none of the anesthetic agents currently in use have been shown to have a teratogenic effect at any gestational age.

• Current data do not support the routine use of tocolytic agents in the intraoperative setting.

Acute Appendicitis

• Acute appendicitis is the most common surgical complication of pregnancy, occurring in 1/1,700 pregnancies.

• Clinical presentation includes the following: anorexia, nausea, vomiting, fever, abdominal pain, rebound tenderness, and leukocytosis with bandemia. In the second and third trimesters, the pain is more likely to be diffuse rather than localized to the right lower quadrant.

• A retrocecal appendix may cause right flank or back pain.

• Seventy percent of pregnant patients with appendicitis demonstrate rebound, guarding, and referred pain, although these findings are less specific in pregnancy.

• Some features of appendicitis are similar to normal symptoms of pregnancy, such as leukocytosis and back pain. However, bandemia can be revealing, and careful physical examination can exclude musculoskeletal pain.

• The differential diagnosis includes the following: ectopic pregnancy, pyelonephritis, acute cholecystitis, pancreatitis, pulmonary embolism, right lower lobe pneumonia, preeclampsia with liver involvement, pelvic inflammatory disease, preterm labor, abruptio placentae, degenerating myoma, round ligament pain, adnexal torsion, ovarian cyst, and chorioamnionitis. Pyelonephritis is the most common misdiagnosis.

• Diagnostic evaluation with ultrasonography is most accurate in the first and second trimesters. In later gestations, positioning the patient in the left lateral decubitus position may assist in identifying the appendix. Magnetic resonance imaging or computed tomography (CT) may be necessary to visualize and evaluate the appendix.

• Management

• Both maternal and perinatal morbidity and mortality are increased for appendicitis in pregnancy. Surgery should not be postponed until the presentation of generalized peritonitis. Treatment is only delayed if the patient is in active labor.

• For ruptured appendix with active labor, cesarean section may be appropriate. A stable, nonseptic patient with a ruptured appendix in the later stages of labor may have a vaginal delivery.

• Perioperative antibiotics with a second-generation cephalosporin, extended spectrum penicillin, or triple antibiotic therapy (ampicillin, gentamicin, clindamycin) are administered in all cases and continued

postoperatively until 24 to 48 hours afebrile in cases of peritonitis, perforation, or periappendiceal abscess.

• Laparoscopy may be useful if the diagnosis is uncertain (e.g., with history of pelvic inflammatory disease) and especially in the first trimester. An open laparoscopic entry technique is advisable after 12 to 14 weeks' gestation due to the increased risk of uterine perforation on entering the abdomen.

• Laparotomy is indicated if suspicion for appendicitis is high, regardless of gestational age. It is also preferred for cases of rupture or generalized peritonitis.

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• The role of preoperative or postoperative tocolysis is not well studied and should be used only for standard obstetric indications.

• Obstetric complications of appendicitis include preterm labor (10% to 20%), spontaneous abortion, and maternal mortality. For uncomplicated appendicitis, the fetal loss rate is about 5%. Perforated appendicitis increases fetal loss to 20% to 25% and carries a maternal mortality risk of up to 4%.

Acute Cholecystitis

• Acute cholecystitis is common, affecting about 1 in 1,000 pregnant women. The increased gallbladder volume, delayed emptying, and decreased intestinal motility during pregnancy predispose to cholelithiasis. Preexisting gallstones rarely cause acute cholecystitis. However, due to the progesterone-induced decrease in gallbladder contractions, approximately 3% to 10% of pregnant women have asymptomatic cholelithiasis. Cholelithiasis is the main cause of cholecystitis in pregnancy, accounting for more than 90% of cases.

• Clinical presentation includes anorexia, nausea, vomiting, fever, and mild leukocytosis, which may also be present at baseline in pregnancy.

• The differential diagnosis includes the following: acute fatty liver of pregnancy, abruptio placentae, pancreatitis, acute appendicitis, HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets), peptic ulcer disease, right lower lobe pneumonia, myocardial infarction, and herpes zoster.

• Diagnostic evaluation consists of history and physical examination, laboratory tests (leukocyte count, serum amylase, and total bilirubin), and ultrasonography of the right upper quadrant. Magnetic resonance cholangiogram and endoscopic retrograde cholangiopancreatography (ERCP) may be performed in pregnancy.

• Management

• Conservative initial management includes bowel rest, intravenous hydration, analgesia, and fetal monitoring. A short course of indomethacin may be considered to decrease inflammation and relieve pain.

• Antibiotics are warranted if symptoms persist for 12 to 24 hours or infection develops.

• Coverage for enteric Gram-negative flora is desired. Typical regimens include piperacillin/tazobactam (Zosyn) or ceftriaxone plus metronidazole.

• ERCP with sphincterotomy and percutaneous cholecystotomy have been reported for management of more severe cases.

• Surgical management is required in approximately 25% of cases and is indicated for failure of conservative therapy, recurrence in the same trimester, suspected perforation, sepsis, or peritonitis.

• Early cholecystectomy, even in uncomplicated cases, decreases the length of hospital stay and the rate of preterm delivery. Some centers proceed to surgery quickly.

• Although laparoscopic cholecystectomy may be performed in all trimesters, consider scheduling cases in the second trimester if possible.

• Intraoperative cholangiography may be indicated if gallstone pancreatitis is suspected. It is safe after organogenesis is complete.

• Complications of acute cholecystitis in pregnancy include the following: gangrenous cholecystitis, gallbladder perforation, choledocholithiasis, and cholecystoenteric fistulas. Severe complications such as ascending cholangitis and gallstone pancreatitis are associated with 15% maternal mortality and 60% fetal loss.

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Bowel Obstruction

• Bowel obstruction during pregnancy is most commonly caused by adhesions (60%) or volvulus (25%).

• Conservative management includes bowel rest, intravenous hydration, and nasogastric suction. Proceed with surgical management if the patient develops an acute abdomen.

Ovarian Torsion and Ruptured Corpus Luteum

• Torsion occurs when an adnexal mass twists on its vascular pedicle. A disproportionate share of these cases occurs in pregnancy (up to one fourth of all torsion cases). Causes of adnexal torsion include corpus luteum cysts, theca lutein cysts, dermoids, other neoplasms, and ovulation induction.

• Clinical presentation includes acute pain (usually unilateral) with or without diaphoresis, nausea, and vomiting. An adnexal mass may be palpable.

• Differential diagnosis includes acute appendicitis, ectopic pregnancy, degenerating uterine myoma, diverticulitis, small bowel obstruction, pelvic inflammatory disease, and pancreatitis.

• Diagnostic evaluation is by history, physical examination, and ultrasonography with Doppler flow to visualize masses, rule out ectopic pregnancy, and observe blood flow to the ovaries.

• Conservative management is indicated for ruptured corpus luteum cysts in hemodynamically stable patients. Corpus luteum cysts usually involute by 16 weeks' gestation.

• Operative management is indicated for acute abdomen, torsion, or infarction.

• Cysts that are persistent, larger than 6 cm, or contain solid elements may require surgery. A laparoscopic approach is often used in the management of adnexal masses in pregnancy.

• If the ovarian corpus luteum is disrupted, progestins can be used up to 10 weeks of pregnancy to prevent miscarriage.

• Complications of torsion include adnexal infarction, chemical peritonitis, and preterm labor.

Breast Mass during Pregnancy

• About 1 in 3,000 pregnant women in the United States is affected by breast cancer. Pregnant patients tend to be diagnosed late. The average delay between symptoms and diagnosis is 5 months.

• Diagnostic evaluation is similar to that of nonpregnant patient.

• Mammography, with abdominal shielding, is safe in pregnancy; however, there is a 50% false-negative rate.

• Breast ultrasonography may differentiate solid and cystic masses without radiation exposure but may also give false-negative results.

• A clinically suspicious breast mass, even with negative imaging, should be biopsied, regardless of pregnancy status. Fine-needle aspiration and core biopsy are safe in pregnancy.

• Management of pregnant patients should avoid external beam radiation and hormonal treatments.

• Chemotherapy may be used after the first trimester, but the patient should be counseled about risks to the fetus.

• Methotrexate, tamoxifen, and anthracycline should be avoided during pregnancy.

• Pregnancy termination should be discussed. However, no survival benefit is shown for first-trimester termination.

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Pregnancy after Bariatric Surgery

• Bariatric surgery is increasingly common among reproductive age women.

• Conception should be delayed for 12 to 24 months after bariatric surgery during the period of most rapid weight loss. In patients who undergo bariatric surgery with a malabsorption component, such as a Roux-en-Y, there is a higher rate of oral contraceptive failure.

• Limited data on pregnancy after bariatric surgery suggest that there is no increase in adverse fetal outcomes. Complications such as gestational diabetes, preeclampsia, and fetal macrosomia may be less common in patients following bariatric surgery than in their obese counterparts but may still occur with greater frequency than the general population.

• Patients who have had gastric banding may need band adjustment during pregnancy.

• Bariatric surgery patients should be appropriately counseled about nutritional goals and risks. Vitamin and mineral deficiencies, including B₁, B₆, B₁₂, folate, vitamin D, iron, and calcium, should be assessed and appropriately treated. In the absence of any deficiencies, blood count, iron, ferritin, calcium, and vitamin D levels can be considered each trimester. Folic acid, B₁₂, calcium, vitamin D, and iron supplements are recommended.

• Complications of bariatric surgery, such as anastomotic leak, bowel obstruction, and band erosion, may manifest as nausea, vomiting, and abdominal pain.

• Use of nonsteroidal anti-inflammatory drugs should be avoided.

TRAUMA IN PREGNANCY

Trauma complicates 6% to 7% of all pregnancies and is the leading cause of nonobstetric maternal death during pregnancy, accounting for 40% to 50% of maternal deaths. The leading causes of trauma in pregnancy include motor vehicle accidents (50%), falls (20% to 30%), physical abuse (10% to 20%), gun violence (4%), sexual assault (2%), and thermal injury/burns (1%).

• During the first trimester, the uterus is mostly protected by the bony pelvis.

• Complications from trauma include preterm labor and delivery, premature rupture of membranes, placental abruption, uterine rupture, fetal-maternal hemorrhage with risk of alloimmunization, direct fetal injury, fetal demise, and maternal bladder rupture.

• Placental abruption is identified in 6% of trauma cases.

• Fetal injury can include skull fractures and intracerebral hemorrhage from blunt pelvic trauma or direct injury

from a penetrating wound.

• Fetomaternal hemorrhage occurs in 9% to 30% of trauma cases. Signs include fetal tachycardia, fetal anemia, and fetal demise.

• Due to the risk of fetomaternal hemorrhage, all Rh-negative pregnant women should receive Rh_o (D) immuno globulin, if appropriate, after trauma.

T rauma Assessment in Pregnancy

• Assessment of the pregnant trauma patient is the same as for nonpregnant patients. The mother should be stabilized first, a primary survey conducted, oxygen administered as needed, and intravenous access obtained. Intubation should be performed early, if necessary, to maintain fetal oxygenation and reduce the risk of maternal aspiration.

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• Primary assessment

• If the gestational age is >20 weeks, place the patient in the left lateral decubitus position or supine with a wedge under the right hip in order to displace the gravid uterus off the inferior vena cava.

• Two large-bore intravenous catheters should be placed and crystalloid administered in a volume three times the estimated blood loss.

• Initiate blood transfusion for estimated blood loss > 1 L. Patients may lose up to 1,500 mL of blood before becoming unstable due to the increased blood volume in pregnancy.

• Avoid vasopressors, if possible, as they depress uteroplacental perfusion. Do not withhold them if they are needed as for cardiogenic or neurogenic shock. See Chapter 3.

• Secondary assessment is performed after initial stabilization.

• Examine the patient's entire body, particularly the abdomen and uterus.

• Assess fetal well-being and estimate gestational age with ultrasound.

• Assess fetal heart rate by doptones or continuous monitoring, depending on gestational age, and place a tocodynamometer for uterine contractions.

• Greater than four contractions per hour during the first 4 hours of monitoring and/or a positive Kleihauer- Betke (KB) test are concerning for abruption. Fewer than four contractions per hour over 4 hours of fetal monitoring and a negative KB are not associated with increased adverse outcomes.

• Perform a pelvic examination to evaluate for bleeding, ruptured membranes, and cervical change.

• Diagnostic evaluation

• CT scan should be performed if indicated and the patient is stable. It should not be delayed due to pregnancy.

• Ultrasonography may be used to screen for abdominal injury and to evaluate fetal age and viability. Ultrasound in trauma is 61% to 83% sensitive and 94% to 100% specific in detecting intra-abdominal injury during pregnancy.

• Diagnostic peritoneal lavage (DPL) is riskier in pregnant patients than in nonpregnant patients but still has a morbidity rate of and carry a fetal mortality rate of up to 42%. CT may help assess the extent of injuries.

• Exploratory laparotomy is performed for any penetrating trauma to the abdomen. Laparotomy for maternal indications is not considered a reason to perform a cesarean section, unless a fetal indication for cesarean delivery is present or if the gravid uterus prevents appropriate intra-abdominal exploration.

• Tetanus prophylaxis should be considered in eligible candidates.

Thermal Injuries/Burns

• Both maternal and fetal outcomes after burn injury are related to the extent of burn area, maternal age and health at baseline, and the gestational age of the fetus. As the burn surface area approaches 50%, mortality exceeds 60% to 70%. In general, mortality parallels burn area for term or near-term pregnant patients with extensive thermal injury.

CARDIOPULMONARY RESUSCITATION IN PREGNANCY

• Fetal survival is improved by restoring maternal circulation.

• Causes of cardiac arrest in pregnant patients include trauma/hemorrhage, pulmonary embolism, amniotic fluid embolism, stroke, maternal cardiac disease, anesthetic complications, and flash pulmonary edema.

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• Standard advanced cardiac life support (ACLS) protocols should be followed without modification for pregnancy.

• Leftward uterine displacement should be used during compressions if it will not compromise the quality of chest compressions.

• Administer drugs and defibrillation per protocol. Pressors should not be withheld, as fetal outcome depends on successful maternal resuscitation.

• Intubate early to reduce aspiration risk.

• Perimortem or emergency cesarean section is rarely required except in patients with a viable fetus who do not respond to resuscitation. In the latter half of gestation, it can improve maternal resuscitation by increasing venous return and cardiac output.

• The decision to proceed with postmortem cesarean section should be made within 4 minutes of cardiac arrest with delivery by 5 minutes for the best outcome. If delivery is delayed more than 10 to 15 minutes, fetal death is likely.

• Perimortem cesarean should be performed immediately at the bedside. A sterile field is unnecessary. Generally, a midline vertical skin incision is made with a scalpel and carried down to the uterus. The hysterotomy is also performed by midline vertical incision. After delivery of the fetus and placenta, the uterus is closed using running locked sutures. Continue cardiopulmonary resuscitation throughout the procedure. If maternal survival is possible, start broad-spectrum antibiotics.

• Infant survival has been reported up to 35 minutes after maternal arrest. Attempt delivery if any signs of fetal life are detected.

• Delivery does not need to be emergent for maternal brain death unless fetal compromise is present.

• Careful documentation of the circumstances and indications for the performance of perimortem cesarean is essential.

SUGGESTED READINGS

American College of Obstetricians and Gynecologists. ACOG committee opinion no. 299: guidelines for diagnostic imaging during pregnancy. Obstet Gynecol 2004;104:647-651.

American College of Obstetricians and Gynecologists. ACOG committee opinion no. 474: nonobstetric surgery in pregnancy. Obstet Gynecol 2011;117:420-421.

American College of Obstetricians and Gynecologists. ACOG practice bulletin no. 105: bariatric surgery and pregnancy. Obstet Gynecol 2009; 113:1405-1413.

Brown HL. Trauma in pregnancy. Obstet Gynecol 2009;114(1):147-160.

Dietrich CS, Hill CC, Hueman M. Surgical diseases presenting in pregnancy. Surg Clin N Am 2008;88:403- 419.

Parangi S, Levine D, Henry A, et al. Surgical gastrointestinal disorders during pregnancy. Am J Surg 2007;193(2):223-232.

Uzoma A, Keriakos R. Pregnancy management following bariatric surgery. J Obstet Gynaecol 2013;33(2):109-141.

Wang PI, Chong ST, Kielar AZ, et al. Imaging of pregnant and lactating patients: part 1, evidence-based review and recommendations. AJR Am J Roentgenol 2012; 198(4):778-784.