thrombocytopenia Opioids represent the mainstay of pain treatment for the pediatric oncology patient General principles of dosing include the following: A dose that is commonly used as a standard starting dose may be insufficient to provide adequate pain relief if the patient is not opioid naïve Far more important than the actual dose is the dose to effect Patients may need repeated doses in order to get control of their pain and repeated doses should not be limited when analgesia has not yet been attained A patient-controlled analgesia (PCA) pump is frequently needed for several types of pain, particularly mucositis where oral intake can be limited In some institutions, such pumps may be initiated in the ED using morphine, fentanyl, or hydromorphone Small children and infants may benefit from nursing-controlled analgesia (NCA) Parents should not control analgesic pumps except in the setting of end-of-life care, per institutional policy Long-acting opioids, such as MS Contin, Oxycontin, and methadone, may be appropriate in the setting of chronic pain These medications should not be used in the setting of acute pain and are rarely initiated in the ED unless in consultation with a pain expert Careful consideration must be given to decisions about whether patients in pain may be discharged to home If oral medications seem to be relieving the pain, then it is generally acceptable to discharge the patient after ensuring an adequate supply of the analgesics for use at home If the pain is inadequately controlled on oral medications and parenteral administration is required, then the patient will need to be admitted NEUROLOGIC COMPLICATIONS OF CANCER TREATMENT Neurologic complications in children with cancer are extremely common and may relate to disease, cancer treatment, or supportive care medications Drug-related side effects are extremely frequent Many of the common problems are reversible but a few can lead to permanent neurologic injury The cancer-specific history is critical to identify the likely causes of neurologic problems The diagnosis and management of neurologic problems in children is covered in Chapter 97 Neurologic Emergencies This section focuses on the unique considerations in the pediatric cancer patient Both motor and sensory peripheral neuropathies are common in children with cancer Vincristine and vinblastine, two chemotherapy agents used to treat many kinds of childhood cancer, cause reversible neuropathy affecting motor, sensory, and autonomic nerves Thalidomide can also cause peripheral neuropathy, which may or may not be fully reversible Initial management tends to focus on establishing the diagnosis by the cancerdirected history and physical examination Pain secondary to chemotherapy