Asystole after alfentanil- succinylcholine

To the Editor: Alfentanil is a new narcotic capable of blunting intraoperalive haemodynamic responses while allowing for return of spontaneous ventilation and consciousness after short surgical procedures. We have recently noted reports of severe bradycardia with the use of alfentanil combined with succinylcholine, t,2 We also present such a case. A 76-year-old 45 kg woman was scheduled for removal of an infected A-V graft in her left arm with repair of the brachial artery using an autologous saphenous vein patch. She had a long history of uncontrolled primary hypertension resulting in renal failure requiring dialysis. Haemodialysis was initiated after a failed four-month trial of peritoneal dialysis. An A-V graft had been inserted two weeks earlier but became infected. Antibiotics were started and she was maintained on peritoneal dialysis. Her volume status was labile and she demonstrated clinical signs of pulmonary oedema when her weight exceeded 50 kg. She denied a history of angina or myocardial infarction. Her blood pressure was variable ranging from l l0 /70-190 / l l0 preoperatively. Despite her infected graft, there were no systemic signs of sepsis. Her volume status was optimized preoperatively. Her medications included captopril 50 mg P.O.t . i .d . , nifedipine 40 mg P.O.b.i.d., propranolol 40 mg P.O.b. i .d. , and digoxin 0.125 mg twice weekly. Preoperative serum electrolytes were normal including a potassium level of 3.8 mEq. Lt. After premedication with lorazepam 2 mg orally 90 minutes preoperatively, she arrived in the operating room calm and alert. Standard monitors including a three-lead ECG pulse oximeter (Nellcor, model N 100) and automatic blood pressure cuff (Critikon, Dinamap) were attached and an infusion of 0.9 per cent saline was begun. Oxygen was administered by mask followed by droperidol 1 mg IV, atracurium 4 mg IV then alfentanil 100 p,g (22 I-~g 'kg -j) which was injected over 40 sec. Thiopentone 75 mg was then given slowly to loss of eyelid reflex. The patient's lungs were ventilated by mask using positive pressure and a bolus of succinylcholine 100 mg 1V was administered approximately 40 sec after the alfentanil had been injected. Positive pressure ventilation with 100 per 255