[Effect of esmolol on cardiovascular responses induced by scopolamine butylbromide].

BACKGROUND

Scopolamine butylbromide (hyoscine-N-butylbromide, HB) is an anticholinergic drug used as a smooth muscle relaxant, and is used even in some surgical procedures during general anesthesia. HB also causes an increase in heart rate as a side effect. The authors evaluated the efficacy of esmolol on hemodynamic changes induced by HB in major abdominal surgery under inhalation anesthesia.

METHODS

Seventeen patients for major abdominal surgery were randomly assigned to control group (C group, n = 9) or to esmolol group (E group, n = 8). Anesthesia was induced with propofol and was maintained with isoflurane-nitrous oxide inhalation and intermittent administration of fentanyl and vecuronium. At the time of bowel anastomosis, 20 mg of HB was administrated as an antispasmodic. In E group, esmolol 0.6 mg x kg(-1) was administered immediately after HB administration.

RESULTS

There were no differences in the patient background between the two groups. At 1 to 10 minutes after HB administration, heart rate increased significantly compared with that at pre-administration in C group, while there was no significant change in heart rate in E group. Heart rate in E group was significantly lower than that in C group at 2 and 3 minutes after HB administration. Blood pressure was not significantly changed in both groups during the observation period.

CONCLUSIONS

The simultaneous administration of HB and esmolol was useful for heart rate control after HB administration.