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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Adolescent, Adult, Aged, Anesthetics, Intravenous, Blood Pressure, Brain Neoplasms, Dexamethasone, Dose-Response Relationship, Drug, Female, Heart Rate, Humans, Male, Middle Aged, Propofol.
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Is propofol requirement decreased in patients with large supratentorial brain tumor? Context: The anesthetic requirement is decreased in animals with head injury, but there are no data regarding the effect of intracranial tumor on the potency for intravenous anesthetics. The authors compared the quantal dose-response curves for propofol in patients having large (> or = 30 mm, mass effect) brain tumor with those having smaller (< 30 mm) lesions and with control patients undergoing noncranial surgery. Sixty patients in each group were randomly assigned to receive one of the six doses of propofol (0.5, 0.7, 1.0, 1.3, 1.8, or 2.5 mg/kg) over 10 s. Two minutes after drug administration, patients were asked to open their eyes as a test for response to verbal command. Patients who failed to respond were given a 10-s, 50-Hz, 80-mA transcutaneous tetanic electrical current to the ulnar nerve as a test for response to painful stimulus. Purposeful movement indicated positive response. Log dose-response curves for loss of response to verbal command and tetanic stimulus were calculated after logit transformation. The median effective doses (ED50s; 95% confidence interval) for suppressing response to verbal command and tetanic stimulus were 0.75 (0.65-0.86) mg/kg and 1.28 (1.11-1.49) mg/kg, respectively, in patients with large brain tumor. These values were significantly less than the corresponding ED50s in patients with small tumor, 1.01 (0.88-1.15) mg/kg and 1.76 (1.51-2.07) mg/kg, or healthy control subjects, 0.98 (0.86-1.12) mg/kg and 1.89 (1.62-2.23) mg/kg.
assistant
The doses of propofol required to suppress response to verbal command and tetanic stimulus were 23% less and 32% less in patients with large brain tumor compared with control subjects. Small tumor did not affect potency of propofol. Final Decision: yes