Lung recruitment in the prone position after cardiac surgery: a randomised controlled study

Area of Science:

• Critical care medicine
• Cardiothoracic surgery
• Respiratory physiology

Background:

• Atelectasis is a common complication following cardiac surgery, leading to ventilation/perfusion mismatch and increased infection risk.
• Recruitment maneuvers are employed to mitigate atelectasis, with potential benefits in severe respiratory failure when performed in the prone position.
• This study investigated the comparative effects of recruitment maneuvers in prone versus supine positions on lung aeration and oxygenation post-cardiac surgery.

Purpose of the Study:

• To compare the impact of recruitment maneuvers in the prone position versus the supine position on lung aeration and oxygenation in patients after cardiac surgery.
• To evaluate the efficacy of prone positioning during recruitment maneuvers in improving key respiratory parameters.
• To assess secondary outcomes including postoperative oxygen requirements and adverse events.

Main Methods:

• Patients undergoing uncomplicated cardiac surgery were randomized to receive recruitment maneuvers (40 cm H2O peak inspiratory pressure, 20 cm H2O PEEP for 30 s) in either the prone or supine position.
• Co-primary endpoints included lung aeration (end-expiratory lung volume via electrical impedance tomography) and oxygenation (PaO2/FiO2 ratio).
• Secondary outcomes comprised postoperative oxygen duration and adverse events. Clinical Trial Registration: NCT03009331.

Main Results:

• Prone recruitment maneuvers resulted in significantly higher dorsal lung tidal volumes (363 a.u. vs. 212 a.u.) and increased end-expiratory lung volume (724 a.u. increase vs. 163 a.u. decrease) compared to supine maneuvers (P<0.001).
• The PaO2/FiO2 ratio was significantly higher after prone maneuvers (46.6 vs. 39.3; P=0.04).
• Postoperative oxygen therapy duration was shorter following prone maneuvers (33 h vs. 52 h; P=0.01), with no reported adverse events.

Conclusions:

• Recruitment maneuvers performed in the prone position after cardiac surgery enhance lung aeration and improve oxygenation.
• Prone positioning during recruitment maneuvers offers a significant benefit for respiratory recovery in the postoperative cardiac surgery setting.
• The findings support the use of prone recruitment maneuvers to optimize lung function and reduce oxygen dependency after cardiac surgery.