The Effects of Nitroglycerine on Pain Control During the Propofol Injection; a Controlled, Double-Blinded, Randomized Clinical Trial

BACKGROUND The use of Propofol often results in pain upon injection, which is sometimes very distressing for patients. Many patients report some degree of pain or discomfort on injection with propofol. Injection-induced pain during induction of anesthesia can result in patient's discomfort. OBJECTIVES This study was performed to evaluate the effects of nitroglycerine on pain severity in patients undergoing propofol injection. PATIENTS AND METHODS In this double-blind randomized clinical trial, 100 patients with ASA class I and II undergoing anesthesia with propofol injection were selected for the study from 2012 to 2013 in Imam Reza training hospital. Patients were randomly assigned to case and control groups and received either 20 μg of nitroglycerine or normal saline as placebo. The severity of injection pain was assessed using a four-point scale. An anesthesiologist observed hemodynamic and local adverse effects. RESULTS The pain severity in nitroglycerine group was significantly lower compared with the placebo group (P < 0.0001). Moreover, the local adverse reactions were observed only in three patients in the placebo group while no patient in the drug group experienced adverse effects (P = 0.242). The systolic blood pressure showed no significant difference between two groups before and after the induction of anesthesia but the diastolic blood pressure and the heart rate was significantly different between study groups. CONCLUSIONS Nitroglycerine may be a safe and effective adjuvant therapeutic for pain reduction in patients under propofol injection. Hence, its use for reduction of propofol injection-induced pain is recommended.