Pain control

Trade-offs

Pain is the most frequent symptom for cancer patients and dis­tressing to all, including caregivers. Caregivers often make assump­tions about what the goal of pain control is for a patient, without engaging the patient in that discussion.

Baseline pain management

We know that pain can be controlled in the majority (>90%) of pa­tients (5). Pain control does not mean that all pain can be removed in most circumstances, but rather its intensity and the subsequent dis­ruption of quality of life can be reduced to tolerable and acceptable levels. In addition, well-trained patients can self-manage their pain with good control (6). Every setting—home, hospital, and hospice— should have systems of care that involve patients and families in re­assessing and adjusting pain management as conditions change (7).

Ongoing chronic pain management

The basis of a pain plan depends on assessment of the source and type of pain and targeting the therapy to this type.

The basis of pain management still rests with the WHO pain ladder, starting with non-narcotic therapies at the base and moving to narcotic medications if the pain is not adequately controlled. For cancer pain, and particularly end of life care, establishing a satisfac­tory around-the-clock base relief system with attention to known side effects from the onset (constipation, somnolence, nausea) is key to success. While controlled-release morphine is the most common base control narcotic used, oxycodone or oxymorphone have also been used with near equal efficacy and side effects (8). Short-acting oral morphine is the cheapest and most widely used opioid worldwide. If a base level of pain control is not achieved with significant progressive cancer pain, and there is availability of ad­vanced localized therapy such as implantable drug delivery systems or nerve blocks for highly localized pain (9), these may address the pain without sedation, constipation, or even fatigue. However, the trade-off may be numbness or loss of function including mobility depending on the area required for the spinal block or implant. The use of epidural and peripheral nerve blocks at the end of life can en­hance analgesia, reduce or deescalate the use of opiates, and still can allow for care at home or in a hospice (10). However, globally, these are either not available or cost prohibitive in many settings.

Broadening availability of oral, subcutaneous, transdermal, and sublingual narcotic options allows good-quality home-based anal­gesia.

Acute pain and rescue management

Breakthrough pain requires analysis of the cause before deciding on an approach. For example, breakthrough pain caused by anxiety will require different management from that caused by disease progres­sion. An escalation in pain may also be due to hyperalgesia associ­ated with the opioid itself which may require switching to another derivative or switching the base management drug (13). This is a rare issue but if the pain is beyond the pre-existing pain and is diffuse in a way that seems out of proportion with the underlying issue, it is worth considering.

Breakthrough pain is best dealt with by rapid-onset formulations of narcotics. However, in some patients with morphine tolerance, consideration of other narcotics for management of recalcitrant breakthrough pain may be needed, such as the use of fentanyl in an intravenous, transdermal, or subcutaneous formulation (14).

Escalation of pain with surgery

It is important to understand that management of pain around sur­gery has a different quality with patients already on significant doses of narcotics to accomplish baseline control of pain. Use of blocks or indwelling epidurals for the local area of surgery or addition of other narcotics to maintain pain control, often in the same pattern as breakthrough pain management, may be needed.

Musculoskeletal pain management

Bone metastases have specific potential therapies for pain manage­ment that should be considered when this is the primary source of pain. Local radiation therapy has long been recognized as ef­fective in palliation of bone pain, with up to 80% receiving relief and up to 50% complete relief from this pain (15). Even a single 8 Gy dose has been shown to provide pain relief equal to longer courses of palliative care, although retreatment is more likely (16). Additionally, bisphosphonates may have a role for pain relief if ra­diation therapy is not adequate or available and pain medicine is not adequate for therapy, although the impact is not as great as ra­diation therapy (17).

Issues from lack of movement/being bed-bound

Musculoskeletal sources of pain can often be more effectively treated by consideration of issues related to lack of movement and posi­tioning. Passive bed physical therapy and massage may often restore circulation and relieve pressure on joints and muscles and provide significant symptom improvement. Additionally, the use of cold or warm compresses can lead to muscle relaxation with concurrent im­provement of symptoms.