Fentanyl-droperidol-nitrous oxide anaesthesia in patients with ischaemic heart disease and various degrees of left ventricular functional impairment.

Haemodynamic stability and left ventricular function (LVF) during induction of anaesthesia and sternotomy were compared in three groups of patients with ischaemic heart disease, angiographically classified as having good, poor and depressed LVF. Anaesthesia was given with fentanyl-droperidol and nitrous oxide. The group with good LVF showed large variations in arterial pressure and heart rate between stimulated and unstimulated states with a reasonable preservation of LVF, expressed as stroke volume, through the whole observation period. The group with poor LVF showed monotonously falling arterial pressure, and no heart rate response to tracheal intubation. These patients maintained remarkably stable stroke volumes in connection with low afterloads. After nitrous oxide, additional volume loading was required because of profound hypotension. The majority of the patients in the intermediate group, labelled "depressed LVF", reacted to intubation and sternotomy with signs of left ventricular failure in connection with tachycardia and increased afterloads. The individual variations between patients with different degrees of left ventricular impairment were considerable, and these haemodynamic patterns need to be confirmed with a larger material.