Comparison of the Efficacy of Sodium Bicarbonate and Lignocaine on Reducing Pain of Rocuronium Injection in Patients Undergoing General Anaesthesia

Abstract

BACKGROUNDNeuro muscular blocking agents have been an essential part of anaesthesia for more than 50 years and commonly used for tracheal intubation and intra operative relaxation. Neuro muscular blockers can be classified as depolarizing agents e.g. Succinyl choline and non-depolarizing agents. Rocuronium a newer amino steroidal muscle relaxant with a rapid onset and intermediate duration of action can be used as an alternative to succinyl choline for intubation. (1) Pain during intravenous injection is the most commonly reported side effect of rocuronium Numerous techniques have been used to reduce the incidence and intensity of this pain. The se include diluting rocuronium, administering it as an infusion rather than as a bolus injection and the use of other medications like lignocaine, antiemetics, antihistaminics, short acting opioids, sodium bicarbonate, ketamine, dexmedetomidine and esmolol. MATERIALS AND METHODSThe study was conducted after obtaining approval of Research methodology and Human Ethical Committee of Government Medical College Trivandrum. Study population includes 120 adult patients of 18-60 years of age and of body weight 50-55 kg of ASA PS 1 & 2 posted for elective general surgery under general anaesthesia. Patients were divided into two equal groups of 60 each according to the order they come for surgery. Group A receives 0.5 ml of 7.5% sodium bicarbonate mixed with Inj. Rocuronium (50 mg). Group B receives 40 mg lignocaine mixed with Inj. Rocuronium (50 mg). Two intravenous lines with 18G IV cannula (One on the non-dominant hand and other on the dominant hand) were inserted and lactated ringers solution was infused at the rate of 100 ml/hr. After pre-oxygenation, a sleeping dose of IV thiopentone is given in the nondominant hand and once the consciousness is lost, the study drug (Freshly prepared) was injected over a period of 10 sec. in the dominant hand and patient was assessed for pain using the 4 point scale of limb withdrawal response. The heart rate and blood pressure response was also noted. Then 1.5 mg/kg preservative free lignocaine is given to both study groups followed by induction dose of Propofol 2.5 mg/kg and waited for 90 seconds. The ease of intubation was noted for both the study groups. Anaesthesia was maintained with nitrous oxide and oxygen (4:2), Inj. Fentanyl 2 µg/kg, Inj. Paracetamol 20 mg/kg IV and Inj. Propofol 75 µg/kg/min iv. The duration of action of Rocuronium was noted in both the studies by noting the time in minutes at which the patient comes out of the relaxant. Heart rate, the duration of action of Rocuronium was noted in both the studies by noting the time in minutes at which the patient comes out of the relaxant. Heart rate, systolic and diastolic blood pressure were recorded before the injection of the study drug, at the time of injection of the study drug, 1 min and 3 min after intubation. Within 24 hours after the operation, the injection site was checked for pain, oedema, wheal and flare response by an anaesthetist who was unaware of which...