Generalized Convulsive Status Epilepticus
(Canada—Canadian Family Physician, September 2000, p. 1817.) Although classic definitions describe seizures lasting 30 minutes, generalized convulsive status epilepticus is regarded by most modern experts as continuous seizures lasting at least five minutes or two or more seizures between which the patient does not fully recover consciousness. On average, a single generalized convulsive seizure lasts 42 seconds with a maximum duration of two minutes. New-onset generalized convulsive status epilepticus can be caused by preexisting epilepsy with inadequate control, or may be precipitated by acute head trauma, encephalopathy, brain hypoxia or drug withdrawal. Some patients with generalized convulsive status epilepticus have prodromal symptoms, but in many cases the condition presents as a crescendo of serial seizures with incomplete recovery. In advanced cases, the deeply unconscious patient may have very subtle signs, such as minor twitching of the limbs, despite severe cerebral hypoxia. Immediate treatment includes maintaining airway patency and protecting the patient from harm. If possible, oxygen should be administered and two intravenous lines established. Lorazepam stops approximately 87 percent of seizures within three minutes, and the effect can last up to 24 hours. Diazepam controls approximately 80 percent of seizures within two minutes, but the effect lasts only 15 to 30 minutes. A common protocol for status epilepticus is lorazepam followed by an infusion of phenytoin at no more than 50 mg per min. Thiamine should be given to patients who have a history of alcoholism or poor nutrition. Glucose and/or electrolyte abnormalities in these patients should be corrected.
Treating Nausea and Vomiting in Advanced Cancer
(Hong Kong—The Hong Kong Practitioner, December 2000, p. 601.) Between 40 and 70 percent of patients with advanced cancer suffer from significant nausea and vomiting. These symptoms may directly result from the cancer, might be caused by a secondary effect such as gastrointestinal blockage or raised intracranial pressure, or could represent treatment side effects. Nausea and vomiting are frequently multifactorial in origin and require a detailed history, physical examination and other investigations to identify the cause. Therapy aims to treat any reversible cause as well as to relieve symptoms. Dietary manipulation, relaxation therapy, guided imagery and distraction may be useful as complete or adjunct treatments. Nasogastric suction, gastrostomy and selective surgical interventions also may help to relieve symptoms in selected patients, but the primary management of nausea and vomiting depends on antiemetic medications. These medications should be started as early as possible, and the dosage should be titrated to optimize the effect. A combination of drugs with different actions may be more effective than high dosages of a single agent. Medication may need to be provided by suppository, parenterally or by other nonoral routes to ensure absorption. Antiemetic drugs act centrally, on the gastrointestinal system, or both to suppress symptoms. Drugs that act primarily on the central nervous system receptors or the vestibular system include butyrophenones (e.g., haloperidol), phenothiazines (e.g., prochlorperazine, chlorpromazine), antihistamines (e.g., cyclizine) and anticholinergics (e.g., hyoscine). Antiemetic drugs with direct effects on the gastrointestinal system include metoclopramide, domperidone and octreotide (an analog of somatostatin). Antagonists of 5-HT3 receptors (i.e., ondansetron and tropisetron) have both central and gastrointestinal effects but are very expensive. Specific medications should be selected to match the drug effect to the cause of the vomiting; side-effect profile; route, timing and form of administration; cost; and patient-specific factors. Each drug is briefly reviewed in the full article, which is available online athttp://www.hkcfp.org.hk/journal.htm.
Management of Chronic Low Back Pain
(Great Britain—The Practitioner, December 2000, p. 1016.)Nonspecific low back pain is often a chronic condition that follows a relapsing and remitting course. Eight “red flags ”have been suggested to differentiate patients with potentially serious conditions who require further investigation or referral. These warning factors are stiffness during inactivity with improvement on exercise, unremitting pain, history of significant trauma, fever, weight loss, abuse of intravenous drugs, high erythrocyte sedimentation rate and patient age of younger than 16 years or older than 50years. Prognosis is characterized by the rule of “sevens. ” The average patient has functional recovery in seven days and symptoms will resolve in seven weeks. Within about seven months, seven of every 10 patients will experience a recurrence of pain.