High intraoperative inspired oxygen does not increase postoperative supplemental oxygen requirements

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Pulmonary Medicine

Background:

• High fraction of inspired oxygen (FIO2) may reduce surgical site infections but raises concerns about postoperative pulmonary complications like hypoxemia.
• Intraoperative positive end-expiratory pressure (PEEP) can enhance postoperative pulmonary function.
• Supplemental oxygen requirement serves as a key indicator of postoperative pulmonary function and hypoxemia.

Purpose of the Study:

• To investigate the impact of intraoperative high fraction of inspired oxygen (FIO2) and positive end-expiratory pressure (PEEP) on postoperative supplemental oxygen requirements.
• To evaluate whether high intraoperative FIO2 ( > 0.9) increases postoperative hypoxemia compared to standard FIO2 (0.3) in patients undergoing lower-risk surgery.

Main Methods:

• A double-blind, 2x2 factorial randomized study involving 100 patients.
• Patients were assigned to intraoperative FIO2 0.3 vs. >0.9, with or without PEEP (3-5 cm H2O).
• Postoperative oxygen saturation was monitored after extubation, with supplemental oxygen added if saturation dropped below 90%.

Main Results:

• All patient groups required supplemental oxygen in the postanesthesia care unit.
• No statistically significant differences in supplemental oxygen requirements were observed at 45 minutes and 24 hours post-extubation between the groups.
• The use of high intraoperative FIO2 did not correlate with increased postoperative oxygen demand.

Conclusions:

• High intraoperative fraction of inspired oxygen (FIO2) does not appear to induce significant postoperative hypoxemia in patients with normal pulmonary function.
• The findings suggest that elevated intraoperative FIO2 may be a safe strategy for surgical patients with otherwise normal respiratory function.
• Further research could explore the specific benefits of high FIO2 in reducing surgical site infections without compromising postoperative respiratory outcomes.