Page 1663 - Hematology_ Basic Principles and Practice ( PDFDrive )

Chapter 91 Pain Management and Antiemetic Therapy in Hematologic Disorders 1481

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regimens for hematopoietic stem cell transplants (SCT). Amifostine When a patient with sickle cell anemia experiences pain, it is
is a thiol compound that is a selective cytoprotective agent approved important to attempt to define the precise cause of the pain before
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for salivary gland protection in patients receiving radiation therapy. attributing it to a vasoocclusive crisis. Acute vasoocclusive pain may
The benefit of using colony-stimulating factors in the treatment of occur along with the chronic pain caused by the long-term complica-
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oral mucositis has been confirmed in at least four controlled trials. tions of compression fractures, avascular necrosis, arthropathies,
They have not achieved widespread use, possibly because of their fractures, avascular necroses, and leg ulcers. 60
high cost. Treating patients with sickle cell pain is complex and requires
Anesthetic cocktails composed of agents such as viscous lidocaine understanding that much of the pain in adults with this illness
(Xylocaine), dyclonine hydrochloride, or a slurry of sucralfate, is chronic with intermittent, recurring painful episodes. For mild
provide temporary relief from oral mucositis-related oral pain. A pain, nonopioid therapy such as NSAIDs or acetaminophen with
variety of mucosal-coating agents have been used to protect mucosal oxycodone or hydrocodone should be considered. However, because
surfaces of the oral cavity including Orabase, Episil, oral antacids, of possible compromise of renal blood flow in these patients and
and Gelclair. There is little evidence from randomized trials to the risk of acute renal failure, NSAIDs should probably not be
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support any benefit from these preparations. Gelclair, a bioadherent used beyond 5 days. Uncontrolled severe pain accounts for more
gel that adheres to the oral surface, creating a protective barrier for than 90% of hospital admissions in adults with sickle cell disease.
irritated tissue, showed a reduction in oral discomfort within 5–7 Using short-acting analgesics on an “as-needed” basis exposes the
hours of initial treatment in an uncontrolled, open-label study of 30 patient to periods of insufficient analgesia, anticipation, and anxiety.
hospice patients (only three of whom had chemotherapy-related Their repeated requests for medication to relieve their ongoing
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mucositis). The more severe cases, occurring in bone marrow pain may be mistakenly interpreted as “drug-seeking behavior,”
transplant recipients, usually require infusional opioid therapy deliv- and they may be unfairly stigmatized. Thus, intravenous analgesics
ered by standard drip or PCA. Pilocarpine (5–10 mg three times daily should be started as a continuous infusion or with PCA. When
1 hour before meals) may improve xerostomia from neck irradiation. adequate analgesia is obtained, a long-acting opioid or a sustained-
However, caution is warranted because of reported side effects of release opioid may be initiated with intermittent use of rescue
glaucoma and cardiac problems. Sugar-free hard candy is also useful medication. In adult patients with frequent episodes of painful
for opioid-induced xerostomia and dysgeusia. crisis, the use of long-acting opioid medications reduced visits to
the emergency department and hospitalizations, and shortened the
lengths of stay in hospital. Meperidine should be avoided in this
Postherpetic Neuralgia population and has been associated with seizures in 1%–12% of these
patients.
PHN, defined as pain persisting beyond 4 months from the initial
onset of the rash, can be a difficult problem for patients with hema-
tologic disorders and has been the subject of several reviews. The Patients With Opioid Addiction
anticonvulsant medications gabapentin, pregabalin, and valproic acid
are especially useful in reducing the lancinating component of the In order to identify and treat patients with opioid addiction, the Food
various pain syndromes generated by this infection. A 2011 systemic and Drug Administration Amendments Act (FDAAA) of 2007
review identified four placebo-controlled randomized trials, with two established the requirement for postmarketing studies and mandated
trials evaluating immediate-release gabapentin at doses between 1800 the implementation Risk Evaluation and Mitigation Strategies
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and 3600 mg daily showing benefit compared with placebo for the (REMS). Statewide Prescription Drug Monitoring Programs
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outcome of “much or very much improved” (38% vs. 20%). Pre- (PDMP) were established to track patients with prescriptions for
gabalin in randomized studies with patients with PHN has shown controlled substances from multiple practitioners (e.g., I-STOP in
improvement in sleep and decrease in pain at doses of 150–600 mg New York State). These systems allow the practitioner to easily refer-
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daily. Because of the risks associated with physical dependence, ence which scripts a patient has filled from which practitioner. Many
tolerance, addiction, and overdose, many experts consider opioids as guidelines for treating non-malignant chronic pain with opioids exist.
second- or third-line options for PHN. 53 Patients with cancer are not immune to the risks of opioid misuse
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TCAs are effective for PHN. One trial concluded that nortrip- and some patients may have a history of substance abuse. It is
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tyline was better tolerated than amitriptyline. Elderly patients, important to screen all patients for a history of or ongoing substance
however, often do not tolerate the anticholinergic side effects, prin- misuse. Patients with risk factors should be managed more strictly
cipally sedation and dry mouth, and therefore nortriptyline (Pamelor), with the use of medication management agreements, urine toxicology
a less anticholinergic TCA, may be useful in these patients. Topical screening, pill counts and possibly more frequent visits with prescrip-
lidocaine (5%) has been used for the relief of pain associated with tions for shorter durations.
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postherpetic neuralgia; however, its role has not been established.
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There are limited data on the efficacy of topical capsaicin (0.075%).
Available evidence of botulinum toxin injection for PNH has not Bone Marrow Transplantation
been well studied, but available evidence suggests it is effective and
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well tolerated. Patients with severe pain refractory to these therapies While some studies have reported pain after bone marrow transplan-
may benefit from a combination of intrathecal methylprednisolone tation, thought to be secondary to bone marrow expansion during
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and lidocaine. 59 the engraftment phase, other studies have incidentally reported
improvement in pain in patients with sickle cell disease after comple-
tion of successful bone marrow transplantation. While there are
Sickle Cell Anemia no studies that specifically look at pain outcomes, several studies
report positive results. One study, which involved fifty children
Patients with sickle cell anemia have chronic and episodic pain (26 with long-term follow-up) with stem cell transplants (SCT),
despite optimal medical therapy, and 60% of patients with sickle cell reported that 22 of the children experienced no further episodes
anemia will have an episode of severe pain each year. Chronic arthritic of pain after transplantation. It is notable that the age range was
pain can be treated with physical therapy and full doses of antiarthritic 4–14 years of age, which is likely to be too young to start develop-
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medication, but some patients require low doses of chronic opioid ing the serious long-term effects of sickle cell disease. Subsequent
therapy to maintain independent functioning. Several studies have studies have demonstrated similar results in children who undergo
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confirmed the safety and efficacy of long-term opioids in the treat- SCT. A recent study of adult patients with sickle cell disease who
ment of pain of nonmalignant origin. In some cases, joint replace- underwent SCT demonstrated that while these patients do con-
ment may be required. tinue to take opioids, they use them at lower doses. Pain in these