Does alfentanil preserve left ventricular pump function during rapid sequence induction of anaesthesia?

A double-blind, randomised trial was conducted in 24 patients without cardiopulmonary disorders (20-43 years), to assess the effect of an intravenous bolus of alfentanil on the circulatory and catecholamine responses to rapid sequence induction of general anaesthesia. Induction included injection of thiopentone 5 mg/kg and suxamethonium 1.5 mg/kg in rapid succession, followed by laryngoscopy and intubation. Half of the patients received alfentanil 100 micrograms/kg immediately before thiopentone. The other half received saline. Blood pressure, heart rate, and plasma catecholamine concentrations were measured repeatedly, together with left ventricular ejection fraction assessed by radionuclide angiocardiography. The responses following laryngoscopy and intubation were completely different in the saline vs. the alfentanil group: rate pressure product +76% vs. -32%, mean arterial blood pressure +46% vs. -25%, heart +46% vs. no change, noradrenaline +117% vs. -25%, adrenaline +50% vs. -53%, and left ventricular ejection fraction -32% vs. no change. In conclusion, during rapid sequence induction of anaesthesia with thiopentone and suxamethonium, an intravenous bolus of alfentanil 100 micrograms/kg 1 min before laryngoscopy and intubation completely prevents hypertension, tachycardia, decrease in left ventricular ejection fraction, and activation of plasma catecholamines, though at the expense of moderate hypotension.