comparative blind study for assessment of Intubating conditions using propofol and remifentanil with and without muscle relaxant

ABSTRACT

Remifentanil is a powerful and ultra-short acting opiate, with a rapid onset of action. It is hydrolyzed by non-specific blood and tissue esterases and it has a half life of approximately 3 min compared with 58.5 min for alfentanil after 4 hours infusion Thus, remifentanil can be administered without fear of accumulation over time. Intubation without neuromuscular blocking agents has been used in a number of different studies. Based on the pharmacokinetic profile of remifentanil, it was hypothesized that it may be very useful in facilitating tracheal intubation. The aim of our study is to determine the quality of intubation using remifentanil 3 micro g/kg and propofol 2 mg/kg compared with the standard use of muscle relaxants. We studied 100 healthy adult patients [ASA physical status I, II], undergoing elective surgery requiring tracheal intubation. They are arranged in two equal groups one group with muscle relaxation given for intubation, while the other group no relaxant was given. Anesthesia was induced with 3 micro g.kg[-1] of remifentanil over 3 min. followed by propofol 2mg.kg[-1] as a bolus over 30 seconds for both groups. Laryngoscopy was performed after assisted ventilation with 50% N2O and 6-8% desflurane in O2 till a bispectral index value [BIS] of < 40% was reached. The trachea was intubated with an appropriate-sized cuffed tube. The study parameters were MAP, HR, and SpO2 which were measured before induction, then every minute until the tube is fixed. A blinded operator scored the ease of intubation using a special scoring system. Adverse events such as laryngospasm, bronchospasm, chest wall rigidity, coughing or post-operative sore throat were recorded if occurred. Intubation conditions were clinically acceptable in both groups with no statistical difference. From this study we conclude that the use of propofol and remifentanil in the given doses provided excellent intubation condition without the need for muscular relaxation