Evaluation of diaphragm ultrasound in predicting extubation outcome in mechanically ventilated patients with COPD

Abstract

Background

To explore the value of the right hemi-diaphragmatic excursion (DE) and its variation in predicting extubation outcome in mechanically ventilated patients with COPD.

Methods

All included patients with COPD received mechanical ventilation (MV) and were ready to wean from MV. After patients passed the 30 min spontaneous breathing trail (SBT), extubation was considered to be feasible, and the right DE measured by ultrasound at 0 min, 5 min, and 30 min of SBT were named as DE ₀, DE ₅, and DE ₃₀, respectively.

Results

Twenty-five patients succeeded extubation; 12 patients failed. The area under receiver operator characteristic curve (AUC _ROC) of DE ₃₀ and ΔDE ₃₀₋₅ (the variation between 30 and 5 min) were 0.762 and 0.835; a cutoff value of DE ₃₀ > 1.72 cm and ΔDE ₃₀₋₅ > 0.16 cm were associated with a successful extubation with a sensitivity of 76% and 84%, a specificity of 75% and 83.3%, respectively. The predictive probability equation of the DE ₃₀ plus ∆DE ₃₀₋₅ was P = 1/[1 + e ^{−(−5.625+17.689×∆DE} ₃₀₋₅ ^+1.802×DE ₃₀ ⁾], a cutoff value of P > 0.626 was associated with a successful extubation with the AUC _ROC of 0.867, a sensitivity of 92%, and a specificity of 83.3%.

Conclusion

The combination of DE ₃₀ and ∆DE ₃₀₋₅ could improve the predictive value and could be used as the predictor of extubation outcome in mechanically ventilated patients with COPD.