Calcium channel blockers attenuate cardiovascular responses to tracheal extubation in hypertensive patients

Comparison of Nicardipine Versus Esmolol in Attenuating the Hemodynamic Responses to Anesthesia Emergence and Extubation

OBJECTIVE

The purpose of this study was to compare the effectiveness of intravenous (IV) nicardipine versus esmolol in controlling heart rate (HR) and blood pressure (BP) responses to emergence and extubation.

DESIGN

Prospective, randomized, double blind.

SETTING

University hospital, single institution.

PARTICIPANTS

Twenty-two American Society of Anesthesiologists physical class 1 to 3 adult inpatients scheduled for general anesthesia.

INTERVENTIONS

General endotracheal anesthesia with oxygen/isoflurane and muscle relaxation. At end of surgery, with at least 2 twitches by nerve stimulator and end-tidal isoflurane <0.4%, muscle relaxant reversal was accomplished with neostigmine and glycopyrrolate. Two minutes postreversal, the IV study drug nicardipine, 0.03 mg/kg, or esmolol, 1.5 mg/kg, was administered. HR and BP were measured every minute up to 10 minutes and at minute 15 postreversal.

MEASUREMENTS AND MAIN RESULTS

There were no significant differences between groups in age, weight, gender, American Society of Anesthesiologists physical class or preoperative hemodynamics (HR, BP, mean arterial pressure [MAP]). Compared with nicardipine, 0.03 mg/kg IV, esmolol, 1.5 mg/kg IV, significantly (p < 0.05) attenuated HR more than nicardipine for the 15-minute time period poststudy drug. Compared with esmolol, nicardipine was significantly (p < 0.05) more effective in controlling MAP and systolic BP for the 1- to 3-minute and diastolic BP for the 1- to 2-minute time periods poststudy drug. There were no episodes of hypotension or adverse events.

CONCLUSIONS

Although esmolol, 1.5 mg/kg, IV was more effective than nicardipine, 0.03 mg/kg, IV for attenuating the HR response to extubation, nicardipine was more effective in controlling the BP response.

Combined diltiazem and lidocaine reduces cardiovascular responses to tracheal extubation and anesthesia emergence in hypertensive patients

PURPOSE

Hypertensive patients exhibit exaggerated cardiovascular responses to tracheal extubation. This study was undertaken to compare the efficacy of combined diltiazem and lidocaine with each drug alone in suppressing the hemodynamic changes during tracheal extubation.

METHODS

Sixty hypertensive patients (ASA II), defined as systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg (WHO), undergoing elective orthopedic surgery received, in a randomized, double-blind manner, 0.2 mg x kg(-1) diltiazem, 1.0 mg x kg(-1) lidocaine, or 0.2 mg x kg(-1) diltiazem plus 1.0 mg x kg(-1) lidocaine (n=20 of each) i.v. before tracheal extubation. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and after tracheal extubation.

RESULTS

Hemodynamic changes during tracheal extubation were less in patients receiving diltiazem plus lidocaine than in those receiving diltiazem or lidocaine as a sole medicine (RPP; 10322 +/- 1674 (combined) vs 11532 +/- 1802 (diltiazem), 15388 +/- 2050 (lidocaine), mean +/- SD, P < 0.05).

CONCLUSION

Combined diltiazem and lidocaine is more effective prophylaxis than diltiazem or lidocaine alone for attenuating the cardiovascular responses to tracheal extubation and emergence from anesthesia in hypertensive patients.