Mechanical Power in ARDS Management
Introduction to Mechanical Power
- The American Thoracic Society recommends that all patients with ARDS receive ventilation with a low tidal volume of 4-8 ml/kg predicted body weight and a plateau pressure ≤30 cmH2O to minimize mechanical power and ventilator-induced lung injury (VILI) 1, 2, 3, 4, 5, 6, 7
Ventilation Strategies
- For moderate to severe ARDS, use higher PEEP (average 15.1 ± 3.6 cmH2O) compared to lower PEEP (average 9.1 ± 2.7 cmH2O) to reduce mortality 8, 9
- Prone positioning for more than 12 hours a day is recommended for severe ARDS (PaO2/FiO2 <150 mmHg) without increasing mechanical power 1, 2, 3, 4, 5, 6, 7
Recruitment Maneuvers
- Recruitment maneuvers can be considered in moderate to severe ARDS with close hemodynamic monitoring, but should be avoided in patients with hypovolemia or shock 8, 9, 10, 11
Monitoring and Adjustment
- Monitor plateau pressure, driving pressure, and dynamic compliance to evaluate mechanical power and the risk of VILI 7
- Adjust ventilation settings to maintain a mechanical power <20 J/min and a plateau pressure ≤30 cmH2O 1, 2, 3, 4, 5, 6, 7
Normalization and Evaluation of Risk
- Calculate normalized mechanical power to evaluate the risk of VILI and adjust ventilation settings accordingly 7
Pitfalls to Avoid
- Avoid using absolute mechanical power without normalization, as it does not have a causal relationship with mortality 7
- Do not delay prone positioning in severe ARDS, as it should be implemented early, not as a last resort 7