Comparative Evaluation of Sevoflurane, Propofol, and Combination of Sevoflurane and Propofol on Insertion Characteristics of Reusable Classic Laryngeal Mask Airway

BACKGROUND AND AIM: Adequate depth of anaesthesia is needed for successful placement LMA. under lighter plane of anaesthesia inadequate mouth opening,coughing,body movements can lead to rejection of LMA and may be associated with breath holding and bronchospasm. Use of propofol in doses which allow adequqate jaw relaxation and prevent patient reaction to LMA commonly results in hypotension and prolonged apnoea. Apart from minimal respiratory irritant properties sevoflurane as compared to propofol has the advantage of providing better hemodynamic stability and a smoother transition to the maintainance phase without a period of apnea. However sevoflurane is associated with delayed jaw relaxation and a longer time for the insertion of the LMA.Our hypothesis is that induction of anaesthesia with the combination of sevoflurane and small dose of propofol may optimize the insertion conditions of LMA and decrease the side effects of individual drugs. METHODS: 90 patients aged 18-65 yrs ASA physical status I and II undergoing elective procedures were randomly allocated into 3 groups of 30 patients each. No patient had been given any premedication. Patients in group P were induced with iv inj propofol 3 mg/kg. Patients in group S an SP were induced with tidal volume breathing induction technique using sevoflurane 8% along withN20: 02: 67:33 @ 6L/MIN In addition, in group SP after loss of eye lash reflex patients were given IV propofol 1.5 mg/kg. An independent observer assessed insertion characteristics. RESULTS: our results showed that induction of anesthesia using the combination of sevoflurane and propofol resulted in the most frequent successful LMA insertion at first attempt as compared with induction of anesthesia with either sevoflurane or propofol alone.