Effect of High-Flow Nasal Oxygen Versus Conventional Oxygen Therapy on Postoperative Atelectasis in Obese Cardiac Surgical Patients: Randomized Controlled Trial

Background aims There is a high incidence of postoperative atelectasis in obese patients undergoing cardiac surgery. High-flow nasal oxygen (HFNO) therapy may decrease the incidence and severity of atelectasis in obese patients. This study aimed to compare the effects of HFNO on postoperative atelectasis with conventional oxygen therapy in obese patients after cardiac surgery with fast-track extubation. Material and methods This prospective, randomized, controlled, open-label study was done at a tertiary care hospital. Seventy-two patients of either gender of age 18-60 years with body mass index ≥30 kg/m², scheduled to undergo elective cardiac surgery received either HFNO (group H, n=36) or conventional oxygen therapy using Hudson mask (group C, n=36) after extubation. The incidence of atelectasis was the primary outcome variable. Results In group H, the incidence of atelectasis was lower at 24 (63.9% versus 88.9%, p=0.025) and 72 (58.33% versus 86.11%, p=0.017) hours after extubation. The severity of atelectasis and shunt fraction were lower in group H at 24 and 72 hours. The partial pressure of oxygen (PO₂) and the ratio of PO₂ and fraction of inspired oxygen were higher with HFNO use. The duration of oxygen therapy and intensive care unit stay was shorter in the HFNO group. Conclusion It is concluded that HFNO is superior to conventional oxygen therapy for oxygenation after extubating obese patients undergoing cardiac surgery, resulting in reduced atelectasis and improved oxygenation.