Tianjie Zhang,1 Yan Liu,1 Dongwei Xu,2 Rui Dong,1 Ye Song1 

1Department of Ultrasonography, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, 201318,People’s Republic of China; 2Department of Critical Care Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, People’s Republic of China

Correspondence: Ye Song, Email songy_18@sumhs.edu.cn

Background: This study aims to evaluate the predictive value of bedside ultrasound evaluation of diaphragmatic dynamics in determining successful extubation outcomes for patients eligible for weaning.
Methods: This prospective observational study was conducted on patients who were mechanically ventilated and ready for weaning during the spontaneous breathing trial (SBT). The diaphragm contraction and motion-related parameters of patients such as end inspiratory diaphragm thickness (DT-insp), end respiratory diaphragm thickness (DT-exp), diaphragm thickening fraction (DTF), diaphragmatic thickening fraction rapid shallow breathing index (DTF-RSBI), diaphragmatic excursion (DE), diaphragmatic excursion rapid shallow breathing index (DE-RSBI) were recorded and the association with failure in ventilatory extubation was analyzed. A receiver operating characteristic (ROC) curve was conducted to analyze the prediction of successful weaning.
Results: Out of 95 patients, 14 (14.74%) died, and 68 (71.58%) were successfully extubated. There were significant differences between the two groups in all parameters except DT-exp. The results indicated that duration of mechanical ventilation (OR = 0.850, 95% CI: 0.770– 0.938, P = 0.001), DTF (OR = 1.214, 95% CI: 1.108– 1.330, P = 0.000), DTF-RSBI (OR = 0.917, 95% CI: 0.880– 0.954, P = 0.000), DE (OR = 127.02, 95% CI: 15.004– 1075.291, P = 0.000), DE-RSBI (OR = 0.752, 95% CI: 0.657– 0.861, P = 0.000) had predictive value for weaning. DTF and DE had a high sensitivity of 91.18%, 100%, respectively. Whereas, duration of mechanical ventilation, DTF-RSBI, DE-RSBI showed a high specificity of 81.48,85.19%, 81.48%. Considering all the above factors, the sensitivity was 88.24% and the specificity was 88.89%.
Conclusion: Bedside ultrasound assessment of diaphragmatic parameters enables the detection of diaphragmatic dysfunction, thus proving valuable in predicting extubation success and facilitating a favorable weaning outcome.

Keywords: diaphragmatic dynamics, bedside ultrasound, extubation, intensive care unit