Low-dose fentanyl: haemodynamic response during induction and intubation in geriatric patients

Twenty-eight surgical patients aged 65-84 were randomly assigned to either a control group (12) induced with thiopentone alone, or a treatment group (16), induced with 3 micrograms . kg-1 fentanyl followed by thiopentone, to determine whether the use of fentanyl during induction would attenuate the cardiovascular response to laryngoscopy and intubation. Patients in the fentanyl group required 47 per cent less thiopentone for induction. Increases in systolic (SBP) and diastolic (DBP) blood pressure were significantly smaller in the group receiving fentanyl at one minute post intubation. SBP rose by 56 mmHg in the control group, compared to 15 mmHg in the fentanyl group; DBP increased 42 mmHg compared to 20 mmHg, respectively. Increases in rate-pressure product were twice as great in the control group compared to the fentanyl group (72.2 vs 36.0 per cent, respectively). Thus, fentanyl, as an adjunct to barbiturate induction, effectively lowered the thiopentone requirement and attenuated the pressor response to laryngoscopy and intubation.