I. Matot et al., The effect of clonidine premedication on hemodynamic responses to microlaryngoscopy and rigid bronchoscopy, ANESTH ANAL, 91(4), 2000, pp. 828-833
Citations number
33
Categorie Soggetti
Aneshtesia & Intensive Care","Medical Research Diagnosis & Treatment
The usual hemodynamic response to laryngoscopy and bronchoscopy is an incre
ase in heart rate and arterial blood pressure. Previous work has reported t
hat 10%-18% of the patients develop ischemic ST segment changes during the
procedure. Therefore, we performed a prospective, randomized, double-blinde
d study in 36 patients scheduled for elective microlaryngeal and bronchosco
pic surgical procedures to evaluate the effects of 300-mu g oral clonidine
premedication (n = 18) or placebo (n = 18) on the hemodynamic alterations a
nd 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) c
ompared with the baseline and with the clonidine group. A dose of 300-mu g
clonidine blunted the hemodynamic response to endoscopy. Ventricular arrhyt
hmias were more frequent in patients who were not premedicated with clonidi
ne. Two patients in the control group, but none in the clonidine group, had
evidence of myocardial ischemia. These data should encourage routine preme
dication with clonidine in patients undergoing microlaryngoscopic and bronc
hoscopic procedures.