The Effect of Clonidine Premedication on Hemodynamic Responses to Microlaryngoscopy and Rigid Bronchoscopy

Abstract

The usual hemodynamic response to laryngoscopy and bronchoscopy is an increase in heart rate and arterial blood pressure. Previous work has reported that 10%-18% of the patients develop ischemic ST segment changes during the procedure. Therefore, we performed a prospective, randomized, double-blinded study in 36 patients scheduled for elective microlaryngeal and bronchoscopic surgical procedures to evaluate the effects of 300-microg oral clonidine premedication (n = 18) or placebo (n = 18) on the hemodynamic alterations and the incidence of perioperative myocardial ischemic episodes. Myocardial ischemia was assessed by using continuous electrocardiographic monitoring, beginning 30 min before, and lasting until 24 h after the operation. During the procedure, patients receiving placebo exhibited a significant increase (mean +/- SD) in arterial blood pressure (the systolic increasing from 137+/-11 to 166+/-17 mm Hg, the diastolic increasing from 80+/-11 to 97+/-14 mm Hg) and heart rate (increasing from 79+/-15 to 97+/-12 bpm) compared with the baseline and with the clonidine group. A dose of 300-microg clonidine blunted the hemodynamic response to endoscopy. Ventricular arrhythmias were more frequent in patients who were not premedicated with clonidine. Two patients in the control group, but none in the clonidine group, had evidence of myocardial ischemia. These data should encourage routine premedication with clonidine in patients undergoing microlaryngoscopic and bronchoscopic procedures.

Pharmacologic Myocardial Protection in Patients Undergoing Noncardiac Surgery: A Quantitative Systematic Review

“…Thirty-seven of these were subsequently rejected: 24 did not report on relevant endpoints, 4 were on diagnostic procedures (11)(12)(13)(14) (2 were on the same cohort (13,14)), 2 were not randomized (15,16), 1 compared two nitroglycerin regimens (17), 1 had an insufficient follow-up period (18), 1 was too small (19), and 1 (20) contained the same data as another full report that had been published in the same year (21) (only one publication (20) was analyzed by us).…”

Perioperative use of α2-adrenoceptor agonists and the cardiac patient

“…In patients being prepared for surgery, use of clonidine was associated with reductions in BP and HR [33,68,69]. Haemodynamic lability was also attenuated [37,68,[70][71][72], though responses to intubation were not always blunted [33]. Patients premedicated with clonidine 5 µg kg Ϫ1 in preparation for CABG exhibited more favourable intraoperative 364 R. Aantaa and J. Jalonen Comparison of primary haemodynamic parameters in patients undergoing elective plastic surgery (n ϭ 30, ASA I) following premedication with dexmedetomidine (2.5 µg kg Ϫ1 ) or clonidine (4 µg kg Ϫ1 ).…”

Comparative Evaluation of Oral Clonidine and Oral Atenolol as Premedication in Functional Endoscopic Sinus Surgery (FESS) Under General Anaesthesia

“…Matot et al [19] , Singh and Arora [20] and Gupta et al [21] studied the hemodynamic stability after oral clonidine and oral atenolol premedication and reported decrease in pulse rate and blood pressure. In present study, there was a significant decrease in PR, SBP, DBP and MAP in both the groups inspite of surgical stimulus.…”