A Comparison of Propofol and Etomidate for Cardioversion

Abstract

Bolus doses of propofol in patients for cardioversion often produce hypotension and apnea. Etomidate provides cardiovascular stability in these patients, but myoclonus may interfere with electrocardiographic interpretation. This study was designed to demonstrate whether propofol, when given as a low-dose infusion, can attain etomidate's hemodynamic stability without its attendant side effects. Forty consenting patients were randomly assigned to receive either propofol infusion (50 mg/min) for induction of anesthesia followed by a maintenance infusion (100 micrograms.kg-1.min-1) or etomidate (8 mg/min and 20 micrograms.kg-1.min-1). Calculation of loading infusion rates for propofol and etomidate resulted in averages of 0.64 mg.kg-1.min-1 (range, 0.39-1.04) and 0.09 mg.kg-1.min-1 (range, 0.05-0.14), respectively. Induction times (2.2 min) and the times from terminating drug administration to awake states (4.5 min) were similar for each group. Etomidate produced myoclonus in 45% of the patients; otherwise side effects were minimal, with no significant differences between groups. The means of systolic blood pressures in the etomidate group rose a maximum of 15.3 +/- 7.9% (95% confidence), while a modest decrease of 7.2 +/- 7.3% occurred with propofol. Administration of propofol by infusion for cardioversion retains all its beneficial qualities while attenuating its hypotensive effects, making it a suitable choice for these patients with cardiac arrhythmias.

Is propofol an optimal agent for procedural sedation and rapid sequence intubation in the emergency department?

“…Three were excluded because they were foreign language, 1 because it was a case report and 1 because it did not compare propofol to another intervention arm. Six studies with a total of 218 patients met the defined eligibility criteria and were included for review (Table 1), [18][19][20][21][22][23] although only 2 of these studies were blinded. 19,23 Drug administration All 6 studies evaluated propofol in patients undergoing elective cardioversion but none specifically addressed ED cardioversion.…”

Anaesthesia for cardioversion

“…Etomidate has been used alone for cardioversion [39,40,46,47], or with fentanyl to provide analgesia [48]. However, it produces pain on injection in most patients, prolongs recovery compared with propofol [49], causes myoclonus on induction which may interfere with electrocardiographic interpretation [39,46,47,49] and causes postoperative nausea and vomiting. These complications are in addition to the inhibitory effects of etomidate on the adrenal cortex.…”

“…Propofol is probably the drug which most closely approaches the ideal agent for cardioversion [36,41,47,51,521. It is formulated as a ready-to-use solution, is subjectively pleasant at induction, produces Anac.sr/wsirr.…”

“…The only major drawback of propofol is the decrease in blood pressure which accompanies bolus administration. This has been successfully combated by giving it as an infusion rather than by bolus injection [47].…”

“…Etoniidate may be the safest agent in this respect, but it has other deleterious effects. Infusions of anaesthetic drugs have been used and shown to produce less cardiovascular depression than bolus doses [47].…”