Propofol infusion for induction and maintenance of anesthesia in elderly patients: recovery and hemodynamic profiles.

STUDY OBJECTIVE

To evaluate the effect of propofol infusion for both induction and maintenance of anesthesia on hemodynamics and recovery in elderly patients compared with conventional thiopental-isoflurane anesthesia.

DESIGN

Randomized, prospective, study.

SETTING

Teaching hospital.

PATIENTS

60 nonpremedicated ASA physical status I, II, and III adult elderly patients scheduled to undergo total hip replacement surgery.

INTERVENTIONS

Patients received either intravenous propofol infusion at 0.75 mg/kg/min or thiopental bolus 2 to 4 mg/kg for induction, followed by variable-rate propofol infusion up to 0.15 mg/kg/min or isoflurane 0.5% to 1.5% for maintenance of anesthesia. Nitrous oxide and fentanyl supplements were given in all patients.

MEASUREMENTS AND MAIN RESULTS

Perioperative hemodynamic changes, patient recovery profile, and myocardial ischemia incidents were assessed in both anesthetic groups. Induction of anesthesia by propofol infusion (1.6 mg/kg) did not produce significant hypotension (-8.3% +/- 5.5%) or bradycardia; these changes were similar to induction by thiopental bolus injection (3.3 mg/kg). Furthermore, increases in blood pressure and heart rate (HR) during endotracheal intubation were limited to 6% following propofol induction compared with 22% for thiopental induction. During maintenance of anesthesia, the decrease in MAP and HR was comparable in both anesthetic groups. Postanesthetic recovery times for patient to achieve wakefulness, mental orientation, and a maximum Aldrete score (10) were significantly faster in the propofol group, by 4 minutes, 6 minutes, and 20 minutes, respectively; however, the time to discharge from the postanesthesia care unit was not different. Holter-monitored perioperative myocardial ischemic events detected in 23% of the patients occurred independent of hemodynamic changes or the type of anesthetic administered.

CONCLUSION

Induction of anesthesia by propofol infusion in elderly patients produces greater attenuation of cardiovascular sympathetic response than thiopental bolus induction. Induction and maintenance of anesthesia by propofol infusion results in more rapid recovery in our elderly patients than thiopental isoflurane anesthesia.