Propofol Versus Thiopental for Rapid-Sequence Induction in Isolated Systolic Hypertensive Patients: A Factorial Randomized Double-Blind Clinical Trial.

Objective: We investigated the effects of four different anaesthesia induction protocols on the haemodynamic response to laryngoscopy and tracheal intubation during rapid-sequence induction (RSI) in systolic hypertensive patients.

Methods: One hundred and twenty hypertensive adult patients (systolic pressure >140 mmHg and diastolic pressure <90 mmHg), classified according to the American Association of Anesthesiologists as Class II and III were randomized into four groups. After pre-oxygenation for 3 minutes, induction and tracheal intubation were performed by blinded investigators, who also scored the intubation. Study groups composed of 30 patients each received lidocaine 1 mg kg-1 +thiopental 5 mg kg-1 or remifentanil 1 μg kg-1 +thiopental 5 mg kg-1 or lidocaine 1 mg kg-1 +propofol 2 mg kg-1 or remifentanil 1 μg kg-1 +propofol 2 mg kg-1 . Succinylcholine was the muscle relaxant. Haemodynamic data were obtained before (baseline) and after induction, at intubation, and at 1, 3, 5 and 10 minutes after intubation. A rise or drop in the arterial blood pressure and heart rate >20% were considered to be significant.

Results: Patients receiving remifentanil+propofol had a reduction in the systolic and mean blood pressure >20% when compared to patients receiving remifentanil and thiopental: systolic values were 125±27 mmHg in the remifentanil+propofol group versus 153±35 mmHg in the remifentanil+thiopental group 1 minute after intubation (p<0.01); the mean arterial pressure values were 87±18 mmHg in the remifentanil+propofol group versus 105±25 mmHg in the remifentanil+thiopental group 1 minute after intubation (p<0.05).

Conclusion: Propofol was not superior to thiopental for the attenuation of the response to laryngoscopy and intubation during RSI in systolic hypertensive patients, whereas propofol+remifentanil combination appears to be so in terms of the heart rate stability.