Objective: To assess in a group of COPD patients mechanically ventilated for an episode of acute respiratory failure the respiratory mechanics with a simple and non invasive method at the bedside in order to evaluate if these parameters may be predictive of weaning failure or success. Design: A prospective study. Setting: Intensive care and intermediate intensive care units. Patients: 23 COPD patients ventilated for acute respiratory failure and studied within 24 hours from intubation. Methods: Using end-expiratory and end-inspiratory airway occlusion technique, we measured PEEPi, static compliance of the respiratory system (Crs, st) maximum respiratory resistance (Rrsmax) and minimum respiratory resistance (Rrsmin). Measurements and results: The weaned group (A) and the not weaned group (B) were not different regarding to static PEEPi (group A 8.5±4.0 vs group B 8.9±2.6 cmH2O), to Rrsmax (22.4±5.3 versus 22.2±9.0 cmH2O/l/s) and to Rrsmin (17.6±5.5 versus 17.9±8.0 cmH2O/l/s), while a significant difference (p2O). The threshold value of 88.5 ml/cmH2O was identified by discriminant analysis and provided the best separation between the two groups, with a sensitivity of 0.85 and a specificity of 0.87. Conclusion: Cst, rs measured non invasively in the first 24 h from intubation, provided a good separation between the patients who were successfully weaned and those who failed.
- Respiratory mechanics
- Weaning prediction
ASJC Scopus subject areas
- Critical Care and Intensive Care Medicine