Introduction: Sore throat due cuff over–inflation induced mucosal ischemia is a common side effect of general anaesthesia especially with N2O.Adequacy of cuff inflation can be easily measured using an aneroid manometer.We studied the effect of N2O and Air on intracuff pressure, the number of cuff deflations needed to maintain a cuff pressure of 25 cm H2O and the severity of sore throat caused by using either as carrier gas. Materials & Method: 100 patients, between age of 18 to 60, ASA I or II physical status undergoing laparoscopic cholecystectomy under general anaesthesia were randomly divided into Group N–a mixture of 50% N2O & 50% O2 was used as carrier gas and Group A–a mixture of 50% Air & 50% O2 was used as carrier gas.Post intubation the endotracheal tube cuff was inflated till a pressure of 25 cm H2O using an aneroid manometer and noted every 10 min. Every time the cuff pressure was found to be above or below 25 cm H2O it was reset to 25 cm H2O.Post–extubation all patients were evaluated for complaint of sore throat in the recovery room and 12 hrs post extubation. Results: The percentage rise in intra–cuff pressure in both groups was comparable for 10 minutes (P=0.644) & 20 minutes (P=0.096) but at 30 min (31.68%) it was highly significant (P < 0.001) in Group N. It was highest at 10 min in both groups, decreasing over time (18.08%) till 150 min in Group N and (1.92%) till 50 min in group A. Severity of sore throat was higher in group N both in recovery room and 12 hours post–operatively. Conclusion: Postoperative tracheal mucosal injuries caused by cuff contact are frequent in patients in whom N2O is use as a carrier gas. We recommend the routine use an aneroid manometer for initial cuff inflation as well as for intraoperative monitoring during surgeries done using a N2O based anaesthesia technique. The initial increase in cuff pressure associated with pneumoperitoneum advocates cuff pressure monitoring in all laparoscopic surgeries regardless of the carrier gas used.