Preoxygenation algorithm: sequential PSV and PEEP versus tidal volume breathing. a randomized controlled trial

Area of Science:

• Anesthesiology
• Respiratory Physiology
• Critical Care Medicine

Background:

• Preoxygenation is vital for safe airway management during general anesthesia.
• Standard preoxygenation uses tidal volume breathing (TVB).
• Inadequate preoxygenation poses risks, necessitating improved methods.

Purpose of the Study:

• To evaluate an algorithmic approach for preoxygenation.
• To determine if stepwise addition of pressure support ventilation (PSV) and positive end-expiratory pressure (PEEP) improves oxygenation.
• To compare the time required for adequate preoxygenation using different methods.

Main Methods:

• Two hundred patients with inadequate preoxygenation after 3 minutes of TVB were randomized.
• Groups received continued TVB, or TVB with added PSV, or TVB with added PSV and PEEP.
• The primary outcome was the time to achieve end-tidal oxygen (ETO2) ≥ 90%.

Main Results:

• After 4 minutes, 76% of patients achieved adequate preoxygenation with PSV versus 52% with TVB (P < 0.001).
• The PSV-PEEP group achieved adequate preoxygenation faster than TVB and PSV groups (P < 0.001).
• Total preoxygenation time was significantly reduced with PSV compared to TVB (P = 0.003).

Conclusions:

• An algorithmic approach adding PSV and PEEP improves adequate preoxygenation rates.
• This method may reduce preoxygenation time, enhancing airway management safety.
• No serious adverse effects were observed, supporting its clinical utility for high-risk patients.