CARDIOVASCULAR EFFECTS OF ISOFLURANE AND HALOTHANE IN YOUNG AND ELDERLY ADULT PATIENTS

We have studied the cardiovascular effects of 1 MAC end-tidal concentr ations of halothane and isoflurane in young (n = 40) and elderly (n = 40) adult patients using non-invasive techniques. Cardiac output was m easured by Doppler ultrasonography. Halothane reduced heart rate, syst olic, mean and diastolic arterial pressures and cardiac index in both age groups (P < 0.05). Isoflurane reduced systolic, mean and diastolic arterial pressures also, but reduced cardiac index and heart rate onl y in the older patients (P < 0.05). Halothane depressed cardiovascular state significantly more than isoflurane in the younger adults (P < 0 .05), but cardiovascular depression was similar for the two agents in the older age group. The decreases in systolic and diastolic pressures in the older patients were significantly greater with isoflurane comp ared with halothane (P < 0.05).