RESUMEN
Denitrogenation of the lungs with 100% oxygen before or during induction of anaesthesia is now routine practice. It helps to prolong the duration of safe apnoea by maintaining acceptable SpO[2] values. We have compared three groups of patients each comprising of 25 patients. Group A patients breathed room air during induction whereas group B received preoxygenation for 3 minutes [8 litters/minutes O[2]] and group C patients were given five tidal volume puffs after injection of suxamethonium. The mean SpO[2] in group A at endotracheal intubation was significantly different from group B and C [P=0.000001]. We conclude that five tidal volume puffs during the apnea after injection of suxamethonium are equally safe and practicable compared to 3 minutes preoxygenation in fasting patients undergoing elective surgery