The ratio of parasternal intercostal muscle-thickening fraction-to-diaphragm thickening fraction for predicting weaning failure

Background

Diaphragm dysfunction is associated with weaning outcomes in mechanical ventilation patients, in the case of diaphragm dysfunction, the accessory respiratory muscles would be recruited. The main purpose of this study is to explore the performance of parasternal intercostal muscle thickening fraction in relation to diaphragmatic thickening fraction ratio (TFic¹/TFdi²) for predicting weaning outcomes, and compare its accuracy with D-RSBI in predicting weaning failure.

Materials and methods

We prospectively enrolled consecutive patients from 7/2022–5/2023. We measured TFic, TFdi, and diaphragmatic excursion (DE³) by ultrasound and calculated the TFic/TFdi ratio and diaphragmatic rapid shallow breathing index (D-RSBI⁴). Receiver-operator characteristic (ROC⁵) curves evaluated the accuracy of the TFic/TFdi ratio and D-RSBI in predicting weaning failure.

Results

161 were included in the final analysis, 114 patients (70.8%) were successfully weaned from mechanical ventilation. The TFic/TFdi ratio (AUROC = 0.887 (95% CI: 0.821–0.953)) was superior to the D-RSBI (AUROC = 0.875 (95% CI: 0.807–0.944)) for predicting weaning failure.

Conclusions

The TFic/TFdi ratio predicted weaning failure with high accuracy and outperformed the D-RSBI.