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TABLE 98.9 ETIOLOGY OF ACUTE ALTERATION IN MENTAL STATUS IN CHILDREN WITH CANCER Tumor Primary CNS tumor Metastatic CNS tumor Leukemic or carcinomatous meningitis Hyperleukocytosis Infection Meningitis—bacterial, fungal Viral encephalitis Brain abscess Septic shock Cerebrovascular accident Seizure/postictal state Increased intracranial pressure Shunt malfunction All transretinoic acid (Tretinoin) Cytotoxic chemotherapy Methotrexate Cytosine arabinoside Ifosfamide Thalidomide Supportive care Opiates Benzodiazepines Gabapentin Anticonvulsants Tricyclic antidepressants Antihistamines Dronabinol Leukoencephalopathy Metabolic derangements Hyponatremia/SIADH Hypo/hyperglycemia Hypomagnesemia Uremia Postradiation therapy somnolence syndrome Hypo/hypertension Hypoxia Liver failure Depression SIADH, syndrome of inappropriate antidiuretic hormone The presentation and management of increased ICP is not unique in pediatric cancer patients (see Chapter 97 Neurologic Emergencies ) The differential diagnosis includes tumor (see the “Tumors of the CNS” section) or shunt malfunction more often than treatment effect Tretinoin (all transretinoic acid), an agent uniquely used in the treatment of APML causes increased ICP Children are particularly sensitive to this side effect For patients with severe symptoms attributable to tretinoin, a diagnostic and therapeutic lumbar puncture may be needed Opening pressure should be measured and cerebrospinal fluid should be withdrawn to reduce the pressure (see Chapter 97 Neurologic Emergencies ) Children with cancer are at increased risk of seizures from the causes summarized below and in Table 98.8 Severe metabolic disturbances can result from SIADH or from renal tubular wasting of electrolytes (see “Metabolic Complications of Cancer Treatment” section) Seizures can also be caused by primary brain tumors, particularly supratentorial, CNS metastasis of solid tumors, or carcinomatous meningitis Some chemotherapy agents can cause seizures New-onset seizures can be a sign of a bacterial abscess (more likely with Bacillus cereus bacteremia), fungal abscess, or viral encephalitis such as those caused by herpes simplex virus or CMV The approach to seizure management is not unique in patients with cancer and is addressed in Chapter 97 Neurologic Emergencies Specific consideration should be given to assess and correct metabolic and electrolyte abnormalities Children with cancer are at increased risk of CVAs Specific causes in children with cancer include sagittal sinus thrombosis and intracranial bleeding with contributing factors of hypertension, coagulopathy, thrombocytopenia, intracranial tumor, prior surgery, and radiation Spontaneous intracranial hemorrhage is extremely rare except when the platelet count is less than 5,000/μL (see “Hematologic Complications of Cancer Treatment” section) The approach to diagnosis and management is addressed in Chapter 93 Hematologic Emergencies Specific consideration should be given to assess and correct problems with coagulopathy and/or thrombocytopenia Side effects of some supportive-care medications can include extrapyramidal reactions Symptoms of such reactions can range from oculogyric crisis with mild repetitive eye deviation and/or neck motion to severe torticollis and eye deviations Reactions can also include tardive dyskinesia (“frozen”) and akathisia (restlessness/agitation) The key to diagnosis involves a thorough physical examination and a thorough medication history Dopamine-receptor antagonists used as antiemetics are the most common trigger in cancer patients Such drugs include high-dose metoclopramide; phenothiazines such as compazine, chlorpromazine (thorazine), and thiethylperazine (Torecan); and butyrophenones such as droperidol and haloperidol Since more effective antiemetics, such as serotonin-receptor antagonists, have become available, the use of these drugs has decreased along with the incidence of this side effect If an extrapyramidal reaction is suspected, management should include diphenhydramine mg/kg IV (maximum dose 50 mg) If symptoms are refractory to diphenhydramine, benztropine (Cogentin) should be given at a dosage of 0.02 mg/kg IV (maximum mg) CARDIOVASCULAR COMPLICATIONS Cancer treatment can affect cardiac function in patients during treatment and long after completion of therapy Anthracycline-induced cardiomyopathy is the most common cause of cardiac damage in pediatric oncology patients although only a small percentage are affected Anthracycline chemotherapy, most commonly with doxorubicin (Adriamycin) and daunorubicin (Daunomycin), is widely used in the treatment of leukemia, lymphoma, sarcoma, and embryonal tumors such as neuroblastoma and Wilms tumor These drugs injure and potentially kill individual cardiomyocytes and can cause acute cardiomyopathy during and up to year after the end of treatment Late cardiomyopathy may develop or more years after completion of therapy Typical findings on echocardiogram include decreased shortening fraction/ejection fraction and/or increased afterload Specific risk factors include high total dose (greater than 300 mg/m2), high-dose rate, very young age at treatment, and trisomy 21 Most regimens today are designed to minimize the risk of cardiomyopathy by limiting total dose and dose rate and/or giving dexrazoxane, a cardioprotectant Patients exposed to substantial doses of anthracycline are screened with echocardiograms to look for early cardiac dysfunction Early-onset cardiomyopathy usually presents as acute cardiac failure or cardiac dysfunction out of proportion to a stressor such as sepsis Late-onset cardiomyopathy is generally a slowly progressive process that may be detected on screening Both forms may be associated with arrhythmias The initial management of this problem follows the standard regimen for cardiac failure (see Chapter 86 Cardiac Emergencies ) Radiation to the heart can cause long-term injury to the endothelial surfaces leading to early-onset atherosclerotic vessel and/or valve disease The heart is exposed in mantle radiation for Hodgkin disease and total body irradiation as part of a transplant preparative regimen Hypertension may occur in pediatric oncology patients due to steroid exposure, salt overload, and renal injury from treatment Most hypertension is not an emergency and is better addressed by the treating oncologist as part of long-term management Hypertensive emergencies (see Chapter 37 Hypertension ) are rare in pediatric oncology patients  ... regimen Hypertension may occur in pediatric oncology patients due to steroid exposure, salt overload, and renal injury from treatment Most hypertension is not an emergency and is better addressed... completion of therapy Anthracycline-induced cardiomyopathy is the most common cause of cardiac damage in pediatric oncology patients although only a small percentage are affected Anthracycline chemotherapy,... inappropriate antidiuretic hormone The presentation and management of increased ICP is not unique in pediatric cancer patients (see Chapter 97 Neurologic Emergencies ) The differential diagnosis includes