Diaphragmatic speckle-tracking ultrasound for predicting successful liberation from mechanical ventilation: a systematic review and meta-analysis protocol

Ventilator-induced diaphragmatic dysfunction is increasingly recognised as an important complication of prolonged mechanical ventilation (MV) and a major contributor to difficult weaning and extubation failure. Although bedside diaphragmatic ultrasound has emerged as a useful tool for assessing diaphragm function, conventional indices such as diaphragm excursion and thickening fraction may be influenced by ventilatory mechanics and patient effort. Speckle-tracking ultrasound (STU), a deformation-based technique adapted from echocardiography, allows assessment of diaphragmatic strain and strain rate and may provide a more accurate evaluation of diaphragmatic contractility. However, the predictive utility of diaphragmatic STU for successful liberation from MV remains uncertain. This study aims to systematically review the available evidence on the predictive performance of diaphragmatic speckle-tracking ultrasound for successful weaning from MV in adult patients. This protocol follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and is registered in the PROSPERO database. A comprehensive search will be conducted in MEDLINE (via PubMed), Embase, Scopus, Web of Science, LILACS/BVS and CENTRAL without restrictions on language or publication date. Observational studies and clinical trials evaluating diaphragmatic speckle-tracking ultrasound during the weaning process in adults receiving invasive MV for more than 24 hours will be eligible. Two reviewers will independently select studies, extract data and assess the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool for diagnostic and predictive accuracy studies and the Cochrane Risk of Bias 2 tool for randomised trials. When feasible, meta-analysis will be conducted using Review Manager software. The certainty of the evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE)approach. Ethics approval is not applicable for this study since no original data will be collected. The results will be disseminated through peer-reviewed publication and conference presentations. CRD420261338352.