Impact of Intraoperative Oxygenation Practices on Patient Outcomes

Impact of Intraoperative Oxygenation Practices on Patient Outcomes

This multicenter, cluster-randomized, cluster-crossover clinical trial evaluates the impact of three intraoperative FiO2 (Fraction of Inspired Oxygen) oxygenation strategies-lower (FiO₂ 0.21-0.40), intermediate (FiO₂ 0.40-0.80), and higher (FiO₂ 0.80-1.00)-on postoperative organ injury and mortality in adult surgical patients. The trial aims to determine the optimal oxygenation strategy to improve perioperative outcomes.

The Intraop Ox trial will enroll adult patients undergoing surgery with tracheal intubation. Participating hospitals will be randomly assigned (as a unit) to administer one of three oxygenation strategies during maintenance anesthesia (lower FiO₂ [0.21-0.40], intermediate FiO₂ [0.40-0.80], or higher [FiO₂ 0.80-1.00] each period (month). The primary outcome is a composite of organ injury (acute kidney injury, myocardial injury, lung injury, stroke) or death within 30 days. Secondary outcome is 30-day mortality. Exploratory outcomes are individual components of the composite primary endpoint, surgical site infection, length of stay, and hypoxemia. The study is conducted under a waiver of informed consent due to minimal incremental risk of participating and impracticability of obtaining consent in this cluster-randomized design.

Inclusion Criteria:

• Patient located in a participating operating room
• Planned surgery includes tracheal intubation

Exclusion Criteria:

• Patient is known to be less than 18 years old
• Patient is known to be pregnant
• Patient is known to be a prisoner.
• Patient is American Society of Anesthesiologists (ASA) classification-6 (i.e., organ donor)
• Patient's planned surgical case includes open heart surgery, defined as surgery on the heart or ascending aorta requiring sternotomy or thoracotomy.
• Patient's planned procedure requires prolonged apnea, bronchoscopy, airway surgery, or one-lung ventilation.
• Patient's planned surgical case includes use of extracorporeal membrane oxygenation (ECMO).
• Patient is known to have a history of bleomycin treatment.
• Patient was enrolled in the trial in the prior 30 days.