Perioperative Lung Protection: Clinical Implications.

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Respiratory Physiology

Background:

• Historically, high tidal volumes (VT) were used in intraoperative ventilation to manage atelectasis when positive end-expiratory pressure (PEEP) was not common.
• Growing evidence indicates harm from high VT ventilation, leading to the adoption of low VT strategies in operating rooms.
• Uncertainty persists regarding optimal PEEP and fraction of inspired oxygen (FIO2) levels during surgery.

Purpose of the Study:

• To review the evidence on intraoperative ventilation strategies, specifically tidal volume, PEEP, and FIO2.
• To provide recommendations for optimizing ventilation settings to minimize lung injury and adverse outcomes.
• To clarify the risks and benefits associated with different levels of PEEP and FIO2 during surgery.

Main Methods:

• Review of current evidence and established practices in intraoperative mechanical ventilation.
• Analysis of the impact of tidal volume, PEEP, and FIO2 on patient outcomes, including lung injury and hypoxemia.
• Synthesis of findings to formulate evidence-based recommendations for clinical practice.

Main Results:

• Low tidal volume (6-8 mL/kg predicted body weight) is recommended for all surgical patients.
• High PEEP is associated with increased risk of intraoperative hypotension.
• High FIO2 may contribute to atelectasis and adverse postoperative outcomes, and its benefit in preventing surgical site infections is unproven.

Conclusions:

• Low VT ventilation is a well-established and recommended practice for intraoperative management.
• The use of high PEEP and high FIO2 should be restricted to cases of hypoxemia, with FIO2 increase prioritized over PEEP.
• Optimizing intraoperative ventilation settings is crucial for patient safety and reducing postoperative complications.