The value of three diaphragm ultrasound indices for ventilator weaning

Abstract

Objective This study sought to assess the value of the diaphragmatic thickening fraction (DTF), diaphragmatic-rapid shallow breathing index (D-RSBI) and diaphragm thickening-rapid shallow breathing index (DT-RSBI) in predicting the outcomes of ventilator weaning. Methods A total of 59 patients receiving mechanical ventilation with indications for ventilator withdrawal were included in this study. One hour within the spontaneous breath test (SBT) began, diaphragmatic displacement (DD) and DTF were measured with bedside ultrasonography to instead the tidal volume (VT) in conventional rapid shallow breathing index (RSBT) to calculate D-RSBI and DT-RSBI. Patients were divided into success group and failure group according to the weaning results. Multivariate logistic regression analysis was used to find independent risk factors of weaning failure and receiver operating characteristic (ROC) curve was used to evaluate the efficacy of predicting the outcome of weaning. Results The multivariate logistic regression analysis showed that DTF was an independent factor affecting the success or failure after the correction of other factors (P<0.05), the threshold value is 35%, area under roc curve (AUC) 0.972. Conclusions The DTF can be effectively used to predict the result of weaning from mechanical ventilation, the value of D-RSBI and DT-RSBI in SBT needs to be confirmed by more research. Key words: Diaphragm; Ultrasonography; Breath tests; Ventilator weaning