Effect of Low Dose Propranonol on Perioperative Stress Induced Hemodynamic Changes in Upper Abdominal Surgery

Abstract

Stress response is accompanied by an increased traffic in sympathetic efferent tracts resulting in potentially severe hypertension, tachycardia and is associated with post-operative morbidity. Study establishes the assumption that ‘stress free' general anesthesia is necessarily advantageous. A recent study has suggested that different pre-medication may lead to an alteration in sympatho-adrenal stress response during surgery. Several agents and regimens have been devised to control this stress induced haemodynamic responses including alphablocker droperidol, lignocaine, low dose opioid and cervical extradural blockade.

It has been demonstrated that beta-adrenoceptor blocker, in therapeutic doses, caused only modest reduction in cardiac output while decreasing the incidence of arrhythmia and myocardial ischaemia after laryngoscopy and intubation. It is recommended that their administration to be continued until the day of surgery. Even a single dose of a beta-blocker given as a premedication decreases the incidence of episodes of myocardial ischaemia. Atenolol, a selective beta-blocker, per oral significantly reduces cardiovascular morbidity in non-cardiac surgery. Propranolol, a non-selective beta-blocker, has an added advantage of alleviating effect in anxiety. In addition, cost of propranolol is generally low and the systems required to use them according to the protocol used in this study are already in place.

This prospective study was performed to establish its effects on per-operative haemodynamic response in non-cardiac surgery.

The effect of propranolol on heart rate, systolic arterial pressure and derived value rate pressure product (RPP) on peri-operative period was significantly different from that of placebo effect. The result showed that propranolol significantly reduces heart rate, SAP & thus RPP & reduces peri-operative morbidity and mortality.  

Journal of BSA, Vol. 19, No. 1 & 2, 2006 p.14-19