RÉSUMÉ
Background:The laryngeal mask airway is used to maintain airway during general anesthesia especially for short day-case procedures. A successful insertion of LMA necessitates adequate mouth opening that allows easy insertion of the mask and adequate depth of anesthesia to prevent adverse responses of coughing, gagging, and laryngospasm. The aim of this study was to compare remifentanil -propofol regimen versus magnesium-propofol regimen for induction of anesthesia for LMA insertion
Methods: Fifty ASA 1-2 patients of both sexes, aged between 18-55years who were undergoing short day-case procedures were randomized to receive a pre-induction of either IV bolus 0.3jiig/kg remifentanil, or IV bolus of 40mg/kg 10% magnesium sulphate. This followed by induction of anesthesia by IV bolus of 2mg/kg propofol followed by LMA insertion. Pre-induction[base line], post LMA insertion vital data [heart rate ,blood pressure, respiratory rate and oxygen saturation] and frequency of post induction apnea were recorded. The degree of jaw relaxation was assessed as relaxed or rigid and the degree ofease of LMA insertion was graded on three-point scale [gradel: easy, grade 2: moderately easy, and grade 3: difficult]
Results: There were no statistically significant differences between both groups as regards the pre-induction vital data. There were statistically significant differences between both groups as regards post-insertion heart rate, respiratory rate and oxygen saturation [P-value< 0.05] and there was no statistically significant difference between both groups as regards post-insertion blood pressure. In general both drugs effectively maintain stable post-LMA insertion vital data. Regarding the incidence of post induction apnea, it was higher in remifentanil group [56%] compared to [20%] in magnesium group. There were no statistically significant differences between both groups as regards jaw tone or patients graded as easy [grade 1] or moderately easy [grade 2] for insertion of LMA but there was statistically significant difference between both groups as regards those patients graded as difficult[grade 3] for insertion of LMA [P-value<0.05]
Conclusion: Both remifentanil-propofol and magnesium-propofol regimens weresuccessfully maintaining vital data stability during LMA insertion, facilitated LMA insertion, and prevented untoward events of coughing, gagging and laryngospasm. The incidence of post induction apnea was higher in remifentanil group compared to in magnesium group. However, the overall ease of LMA insertion was found to be higher with remifentani 1-propofol regimen in comparison to magnesium-propofol regimen. So, both regimens can be used for LMA insertion and the choice of any should be individualized according to the patient's health status