Comparative study of haemodynamic response to laryngeal mask airway versus endotracheal tube in hypertensive patients

Abstract

Background: The hemodynamic response associated with laryngoscopy and tracheal intubation may be harmful to certain patients. The laryngeal mask air way (LMA) avoids the need for laryngoscopy and allows positive pressure ventilation of the lungs in appro priate patients. Aim : Study compared the haemodynamic response of tracheal intubation with that of laryng eal mask insertion in hypertensive patients. Methodology : Sixty hypertensive patients between 40-60 years of either sex of ASA grade II were randomly allotted to one of the two groups of 30 each (group ET vs group LMA). LMA insertion or tracheal intubation was performed after induction of anaesthesia with thiopentone, an d muscle relaxation with succinylcholine. Anaesthes ia was maintained with nitrous oxide, oxygen, and inhalati onal anaesthetic as per the need. The heart rate, s ystolic BP, diastolic BP, mean arterial pressure (MAP),SpO2 were measured after induction, immediately after intubation or insertion and at minute 1, 3 and 5. Results: There was a very highly significant difference (P < 0.001) in mean peak increase in heart rate (59.2% i n group ET vs 36% in group LMA). There was a fall in both systolic and diastolic BP after induction i n both the groups of our study. This was followed b y a very highly significant increase in both systolic and di astolic BP after airway instrumentation in both the groups. However the values in group LMA were significantly lower compared to group ET after 1 minute and 3 minutes. The MAP reached maximum value immediately after airway instrumentation. However, the va lues after LMA insertion were significantly lower compar ed to tracheal intubation after 1,3 and 5 minutes. Conclusion: Use of LMA may therefore offer some advantages over tracheal intubation in the anaesthetic management of patients where the avoidance of the pressor respons e is of particular concern.