Intravenous Propofol and Inhalational Sevoflurane for Ease of Classic Laryngeal Mask Airway Insertion in Patients Undergoing Elective Surgery: A Randomised Clinical Trial

Abstract

Introduction: The Laryngeal Mask Airway (LMA) has gained extensive popularity for airway management during surgery. Propofol, the most commonly used induction agent for LMA insertion, causes significant haemodynamic changes. Sevoflurane has the potential to be as good an induction agent as propofol. Aim: To compare ease of insertion of classic LMA in patients undergoing elective surgery using intravenous propofol and inhalational sevoflurane. Materials and Methods: The study was a randomised clinical trial conducted in the Operation Theatres of Midnapur Medical College and Hospital, Medinipur, West Bengal, India, from August 2019 to July 2020. Eighty patients of American Society of Anaesthesiologists (ASA) physical status grade I and II, of both sexes, and aged between 18 years to 65 years were equally divided into two groups: group P (Propofol group) and group S (Sevoflurane group). Group P was given injection Propofol 2.5 mg/kg body weight and group S was given vital capacity breath induction with 8% sevoflurane and oxygen at 8 litres/min. Loss of Consciousness (LOC) was confirmed and induction time was noted for each group. After confirmation of ease of mouth opening, by an independent observer, LMA insertion was attempted. Ease of LMA insertion was assessed by a predefined 18 points table along with time to LMA insertion and number of attempts. Haemodynamic changes and adverse effects were also recorded. Chi-square test or Student’s t-test were used and a p-value ≤0.05 was considered as statistically significant. Results: With respect to age, sex and weight there were no significant differences between the two groups. Induction time was significantly less in group P (51.85±6.66 seconds) compared to group S (68.38±13.93 seconds) (p-value=0.0001), but LMA insertion time, number of attempts and overall ease of LMA insertion conditions according to the 18 points score were comparable between the two groups. Mean arterial pressure at certain points after induction was significantly less in group P (at 3 minute p-value=0.009 and at 5 minute p-value=0.007). Apnea was significantly more in group P (p-value=0.023). Conclusion: Sevoflurane was comparable to propofol for LMA insertion in respect of ease of insertion and insertion time. Although induction time was significantly less for propofol, sevoflurane offered better haemodynamic stability and lesser incidence of apnea.