Diaphragm excursion-time index for predicting early extubation of cardiac surgical patients: A prospective observational study.

Background and Aims: Early extubation is recommended for enhancing recovery in cardiac surgical patients, but premature extubation must be avoided. The diaphragm excursion-time index (DETI) is a novel, recently described index that can predict successful extubation. Its role in early extubation of cardiac patients has not been studied yet. This study was aimed at studying the role of DETI in the early extubation of cardiac surgical patients. Material and Methods: This prospective observational study was conducted at a tertiary care hospital. Bilateral DETI (primary outcome variable), diaphragm excursion (DE), inspiratory time (Ti), and diaphragm thickness fraction (DTF) of 150 adult cardiac surgical patients were assessed at the train-of-four ratio 0.95 and end of spontaneous breathing trial (SBT). Patients were classified as successful early extubation if extubated within 6 h. The secondary outcome variables were DE, DTF, and Ti. Receiver operator characteristic (ROC) was used to determine the predictive value of these variables. Results: Early extubation was successful in 96 patients. DETI, DE, and DTF predicted successful early extubation. DETI≥1.31 cm-s of the right diaphragm at SBT predicted successful early extubation with a sensitivity of 0.890 and specificity of 0.779, with an area under ROC curve 0.858. For the left side, DETI≥1.65 cm-s at SBT had a sensitivity, specificity, and area under ROC curve of 0.902, 0.726, and 0.875 respectively. DETI, DE, and DTF were higher in patients early extubation. Conclusion: For cardiac surgical patients, DETI has high sensitivity and specificity for successful early extubation.