Comparison of dexmedetomidine-propofol versus fentanyl-propofol for insertion of laryngeal mask airway

BACKGROUND AND AIMS: Laryngeal mask airway (LMA) insertion requires anesthesia and suppression of airway reflexes. In search of an optimal drug, we compared dexmedetomidine and fentanyl, in combination with propofol for insertion of LMA. MATERIAL AND METHODS: This study was a prospective double blind randomized study. Eighty patients of ASA class 1&2 were randomly divided into two groups of 40 each. Group D received dexmedetomidine 1 mcg/kg and group F received fentanyl 1 mcg/kg intravenously (IV) over 2 minutes. For induction, propofol 2mg/kg was given IV and 90 seconds later LMA was inserted. We observed apnea time, heart rate, respiratory rate, non invasive blood pressure and oxygen saturation before induction, 30 seconds after induction, 1, 3, 5, 10 and 15 minutes after insertion of LMA. Patient's response to LMA insertion like coughing, gagging or any movement were noted and scored. Statistical analysis of data was done using student t test for parametric data, Chi-square test for non parametric data and SPSS 15.0 for windows software. RESULTS: 37 (92.5%) patients of group D and 35 (87.5%) patients of group F had LMA insertion score of <2 and 5 (12.5%) patients of group F had score >2. Adverse events to insertion of LMA and hemodynamic variables were comparable in both the groups. Number of patients developing apnoea was larger and apnoea times were longer in group F compared to group D. When compared to group F, group D showed an increased respiratory rate. CONCLUSION: Dexmedetomidine can be a comparable alternative to fentanyl as an adjuvant to propofol for providing optimum insertion conditions for LMA and preservation of respiration.