Respiratory Muscle Weakness

ICU-acquired respiratory muscle weakness is presented as a central driver of weaning failure. The core problem in respiratory muscle weakness is a mismatch between respiratory muscle load and diminished capacity. Respiratory muscle weakness in ventilated patients arises from both muscle atrophy and reduced calcium sensitivity of contraction. Reduced calcium sensitivity lowers contractile efficiency and increases energy consumption and carbon dioxide production. Respiratory muscle weakness occurs frequently in patients ventilated for more than 24 hours by the time a weaning attempt is made.