Efficacy of Ephedrine Versus Lignocaine Pretreatment In Preventing Pain Following Propofol Injection: A Prospective, Randomized, Double-blind, Placebo-controlled Study.

摘要

Background: Injection pain and hypotension are the two main adverse effects of propofol. The commonly used lignocaine pretreatment for reducing injection pain has a failure rate between 13- 32 %. There are few studies in literature using ephedrine pretreatment for reduction of propofol injection pain and these studies have also looked at the effect of ephedrine in overcoming hypotension and hemodynamic stability, each with varying results. We studied the effect of ephedrine 50μg/kg pretreatment on prevention of propofol injection pain and hemodynamics.Methods: This prospective, randomized, double-blind, placebo-controlled study was conducted after obtaining institutional ethical committee approval. Patients (eighty one patients) were randomly allocated to one of three groups. Each group consisting 27 (n= 27) patients were to receive one of lignocaine (Group L, n = 27), normal saline (Group S, n = 27) or ephedrine (Group E, n = 27) as pretreatment. Group L- pretreatment with 2% lignocaine 2 ml. Group S- pretreatment with 0.9% normal saline 2ml, Group E- pretreatment with ephedrine 50 μg/kg body weight diluted in normal saline into a 2 ml normal saline solution. Propofol was injected 30 sec later. A blinded researcher assessed the patient's pain level using a four point verbal rating scale.Results: There was no significant difference with respect to patient's characteristics and hemodynamic changes during propofol induction among the three groups. There was a statistically significant difference in the incidence of pain between groups. Patients who received lignocaine pretreatment group had 51.8% pain. The Normal saline pretreatment group had 77.8% pain. Ephedrine pretreatment group had pain as high as 70.4 %.Conclusion: Ephedrine used as pretreatment in dose of 50 μg/kg is neither useful to decrease propofol injection pain nor to maintain better hemodynamic. Introduction With the increasing quality and safety of anesthesia and perioperative care patient satisfaction is one of the top priorities of the anesthesiologist. Propofol is an intravenous (IV) sedative and hypnotic agent commonly used for anesthesia induction; injection pain and hypotension are the two main adverse effects of propofol. The pain on injection of propofol interferes with the patient satisfaction, with incidence between 40-86% (1). Propofol belongs to the group of sterically hindered phenols and injection pain is thought to be mediated by endothelial kinin release (2). Ephedrine is proposed to decrease the release of pain mediators from the vascular endothelium (3).There are few studies using ephedrine pretreatment for reduction of propofol injection pain with variable results. This study was under taken to study the effect of ephedrine 50μg/kg pretreatment on prevention of propofol injection pain and hemodynamic effects. Methods A prospective, randomized, double-blinded, placebo-controlled, study was undertaken after institutional ethical committee approval. Eighty one consented patients of either gender, in age groups 18-50 yrs, with American Society of Anesthesiologists physical status I and II who were scheduled for elective surgery requiring general anesthesia were included in the study. Patients with history of allergy to propofol, patients taking sedatives or analgesics 24 hrs prior to the surgery, neurological or cardiovascular disease, obesity, difficult airway and pregnant female patients were excluded from the study.Patients were allocated to one of three groups according to the random numbers generated by statistical software. Each group consisting of 27 (n= 27) patients, was to receive one of the lignocaine (Group L, n = 27), normal saline (Group S, n = 27) or ephedrine (Group E, n = 27) as pretreatment. Group L- pretreatment with 2% lignocaine 2 ml, Group S- pretreatment with 0.9% normal saline 2ml, Group E- pretreatment with ephedrine 50 μg/kg body weight diluted in normal saline into a 2 ml normal saline solution. All syringes of pretreatment