ISOFLURANE DOES NOT INCREASE THE INCIDENCE OF INTRAOPERATIVE MYOCARDIAL ISCHAEMIA COMPARED WITH HALOTHANE DURING VASCULAR SURGERY

We have studied the incidence of new intra-operative myocardialischaemia (IMI), myocardial infarction (Ml) and cardiac death(CD) in 500 consecutive patients undergoing elective major non-cardiacvascular surgery. Patients were allocated randomly to receiveeither halothane (n = 226) or isoflurane (n = 274) as principalanaesthetic agent. Using real-time ST segment trend analysis(leads V5 and II) IMI (halothane 39%, isoflurane 38%), MI (halothane1.3%, isoflurane 1.5%) and CD (halothane 0.4%, isoflurane 0.7%)did not differ significantly between the two groups. Twenty-threeper cent of IMI episodes were related to haemodynamic disturbances,but unrelated to the type of surgery: 148 supra-aortic (IMI= 39%), 244 abdominal aortic (IMI = 41%) and 108 lower extremityrevascularizations (IMI = 33%). We conclude that the choiceof volatile anaesthetic agent does not influence cardiac morbidityor mortality in this type of patient