[The prone position in ARDS. A successful therapeutic strategy]

Area of Science:

• Critical Care Medicine
• Respiratory Physiology
• Radiology

Background:

• The prone position was suggested in 1974 to improve oxygenation in ventilated patients by enhancing dorsal lung ventilation.
• Studies confirm benefits like better secretion removal, decreased intrapulmonary shunting, and increased functional residual capacity (FRC).
• Despite benefits, the prone position was not widely adopted for adult respiratory distress syndrome (ARDS) until recent studies highlighted its potential, especially with CT findings showing dorsal lung density.

Purpose of the Study:

• To evaluate the impact of repeatedly turning multiple-trauma patients with severe ARDS to the prone position.
• To assess the effects on gas exchange and thoracic computed tomography (CT) findings.
• To investigate the persistence of benefits after returning to the supine position.

Main Methods:

• Seven mechanically ventilated intensive care patients with severe ARDS were included.
• Patients were turned between supine and prone positions every 12 hours using an air-cushion bed.
• Repeated thoracic CT scans were used to monitor atelectasis, and gas exchange parameters were analyzed.

Main Results:

• Patients were intermittently turned for an average of 6.5 days.
• Significant improvement in arterial oxygenation and respiratory quotient was observed, persisting even after returning to the supine position.
• Thoracic CT scans showed a uniform reduction in atelectasis in dependent lung areas, with decreased airway pressures noted.

Conclusions:

• Repeatedly turning patients to the prone position provides long-lasting improvements in arterial oxygenation for severe ARDS patients.
• This intervention aids in the weaning process and can be attributed to improved ventilation-perfusion matching and alveolar recruitment.
• This study is the first to report sustained benefits from repeated prone positioning over an extended observation period (over 6 days).