Preoxygenation with high-flow nasal oxygen versus conventional techniques using anatomical face mask in patients undergoing exploratory laparotomy: A randomised comparative study

Background and Aims: Preoxygenation is crucial during rapid sequence induction, especially in peritonitis patients undergoing exploratory laparotomy who are prone to hypoxaemia. This study compares high-flow nasal oxygen (HFNO) versus facemask for preoxygenation efficacy, laryngoscopy duration, desaturation, arterial blood gases, and patient comfort. Methods: Sixty consenting, haemodynamically stable patients aged ≥15 years, scheduled for exploratory laparotomy, were randomised into two equal groups receiving preoxygenation using either HFNO at 50 L/min for 5 min or standard anatomical facemask (SMO) at 10 L/min. Arterial blood gas samples were obtained preoperatively, 5 min after preoxygenation, and 1 min following intubation. The primary outcome was partial pressure of arterial oxygen (PaO₂) after 5 min of preoxygenation. Secondary outcomes included partial pressure of arterial carbon dioxide (PaCO₂), peripheral oxygen saturation (SpO₂), laryngoscopy duration, desaturation incidence, patient comfort, and haemodynamic parameters. Statistical analysis was performed using independent t -test, Wilcoxon test, and Chi-square test. P