Efficacy Of Different Doses Of Propofol For Tracheal Intubation-A Randomised Clinical Trial

Abstract

Background and Objectives: Endotracheal intubation which is an integral part of General anaesthesia is commonly facilitated by administering muscle relaxants following intravenous induction agent. Keeping the disadvantages of muscle relaxants in mind, intubation without muscle relaxants is an alternative option. Commonly used i.v. induction agent Propofol , because of its unique airway reflex suppression properties, was tried by various authors for endotracheal intubation without the use of muscle relaxants with conflicting conclusions. Opioid supplementation of Propofol apparently improved intubating conditions in some studies. Hence we undertook this study to evaluate the feasibility / nonfeasibility of endotracheal intubation and safety using prefixed doses of Propofol – 2mg/kg or 4mg/kg bodyweight supplemented with 3g/kg Fentanyl without the use of muscle relaxants.. Methodology: Present randomized study was conducted on eighty patients after taking informed written consent, comprising of forty patients each Patients of either sex were randomly allocated into group P1 and group P2 by computer generated random numbers. 1. Group P1 received 2mg/kg Propofol +3μg/kg Fentanyl. 2. Group P2 received 4mg/kg Propofol+ 3μg/kg Fentanyl. SPO2, HR, BP-SBP, DBP, MAP 1 minute after administration of study drugs were recorded. More than 20 % difference between the Pre induction baseline HR and B.P . readings and the corresponding readings 1 minute after the completion of injection of the study drug but prior to laryngoscopy was considered as effect of the xi drug on cardiovascular system. Intubating conditions were assessed - Modified Helbo Hansen Scoring system. SPO2, HR and BP –SBP, DBP, MAP were recorded 1 minute and 3 minutes post intubation. More than 20 % difference between the Pre induction baseline HR and B.P . readings and the corresponding readings 1minute post intubation was considered as pressor response to laryngoscopy and intubation. HR and BP were recorded 3 minutes post intubation to know whether HR and B.P . reached the baseline or not. Results: The demographic changes such as Age, Sex, Weight, BMI were comparable in all the groups. The success rate of endotracheal intubation was 62.5% and 95% in Propofol 2mg/kg + Fentanyl 3μg /kg and Propofol 4mg/kg + Fentanyl 3μg /kg respectively. The total incidence of hypotension was 40% and 83% in Propofol 2mg/kg + Fentanyl 3 μg /kg and Propofol 4mg/kg + Fentanyl 3μg /kg respectively. The incidence of hypersensitivity was noted only in Propofol 4mg/kg + Fentanyl 3 μg /kg group and was 2.5%.