A Randomized Controlled Study to Compare the Efficacy of High Frequency Nasal Oxygenation with Conventional Oxygen Therapy for Postoperative Oxygenation in Patients Undergoing Exploratory Laparotomies.

Abstract

Objective: Postoperative pulmonary complication (PPC) is one of the leading causes of poor surgical outcome leading to longer hospital or intensive care unit stay and mortality especially with upper abdominal surgeries having long duration. High-frequency nasal oxygenation (HFNO) has recently been employed for postoperative oxygenation following extubation in surgical patients.

Methods: Fifty consenting adult patients aged 18-65 years of either sex scheduled for exploratory abdominal surgeries under general anaesthesia (GA) with Assess Respiratory Risk in Surgical Patients in Catalonia score ≥ 26 i.e., moderate to high risk were enrolled. After instituting all routine the American Society of Anesthesiologists recommended monitoring, baseline haemodynamic parameters were recorded. Patients were preoxygenated with 100% oxygen and GA was administered as per standard institutional protocol. Following extubation, patients were randomly allocated into one of the groups comprising 25 patients each where Group C and Group H received conventional oxygen therapy via simple face mask and HFNO respectively. The FiO₂ was titrated (from 45% to 100%) by the anaesthesiologist to maintain a SpO₂ of 95% or more. Arterial blood samples were collected after extubation at various designated time points i.e. 2^nd, 6^th,12^th and 24^th hr, The P/F ratio, PaO₂, PaCO₂, S/F ratio along with haemodynamic parameters, incidence of PPCs/acute hypoxemic respiratory failure (AHRF), atelectasis and comfort score were also recorded.

Results: Significant improvement in all oxygenation parameters following the use of HFNO for postoperative oxygenation; however, PaCO₂, haemodynamic variables, complications, incidence of PPCs/AHRF and atelectasis remained comparable between the two groups.

Conclusion: Preventive use of HFNO for post operative oxygenation amongst moderate to high-risk patients scheduled for exploratory abdominal surgery improves oxygenation.