Yitzhak Cohen1, Eli Feldinger, Daniel Ogorek, Avi A Weinbroum. 1. Department of Anesthesiology and Critical Care Medicine, Tel Aviv Sourasky Medical Center and the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Abstract
STUDY OBJECTIVE: To study patients' requirement for propofol dosages during the course of repeated deep sedation for electroconvulsive therapy (ECT). DESIGN: Prospective study. SETTING: Outpatient psychiatric clinic in a tertiary-care, university-affiliated, 1100-bed metropolitan hospital. PATIENTS: 30 patients undergoing 5-day successive ECT for depression over a 1-month period. INTERVENTIONS: Propofol and subsequently succinylcholine were injected intravenously (i.v.) to obtain deep sedation and relaxation followed by a 60 +/- 5 (SD) joules-ECT. MEASUREMENTS: The dosage that was required to deeply sedate the patients, the duration of the ECT, and interval of time to full wakefulness and coherent response were measured. MAIN RESULTS: 13 of 30 patients 1) required >100% increase in the dose of propofol to achieve the same pharmacological prerequisite sedative endpoint, starting from their third treatment onward; 2) there was a 35% abbreviated duration of the convulsive activity; and 3) there was a 21% shortened interval of time to full wakefulness and coherent communication, starting at the fourth propofol injection. CONCLUSIONS: Repeated injections of propofol in patients undergoing ECT under deep sedation can induce a tolerance-like reaction to the drug.
STUDY OBJECTIVE: To study patients' requirement for propofol dosages during the course of repeated deep sedation for electroconvulsive therapy (ECT). DESIGN: Prospective study. SETTING:Outpatientpsychiatric clinic in a tertiary-care, university-affiliated, 1100-bed metropolitan hospital. PATIENTS: 30 patients undergoing 5-day successive ECT for depression over a 1-month period. INTERVENTIONS:Propofol and subsequently succinylcholine were injected intravenously (i.v.) to obtain deep sedation and relaxation followed by a 60 +/- 5 (SD) joules-ECT. MEASUREMENTS: The dosage that was required to deeply sedate the patients, the duration of the ECT, and interval of time to full wakefulness and coherent response were measured. MAIN RESULTS: 13 of 30 patients 1) required >100% increase in the dose of propofol to achieve the same pharmacological prerequisite sedative endpoint, starting from their third treatment onward; 2) there was a 35% abbreviated duration of the convulsive activity; and 3) there was a 21% shortened interval of time to full wakefulness and coherent communication, starting at the fourth propofol injection. CONCLUSIONS: Repeated injections of propofol in patients undergoing ECT under deep sedation can induce a tolerance-like reaction to the drug.