Assessing Weaning Readiness: Insights from Lung Ultrasound in Critical Care

Weaning from ventilatory support is one of the essential steps in the recovery of patients from the intensive care unit (ICU). Lung ultrasound (LUS) is a promising real-time evaluation approach for assessing lung aeration and diaphragmatic function, followed by weaning assessment, making it a promising new modality for assessing weaning readiness. The current study is designed to evaluate the diagnostic accuracy of LUS in predicting weaning outcomes, as well as the LUS cutoff scores that predict fulfilling weaning, which serve as implicit cues for a decision to extubate.

This prospective and observational study was conducted at a tertiary care hospital from November 2021 to October 2022. The study enrolled 124 patients, aged ≥18 years, who had been on mechanical ventilation for at least 48 h. LUS was performed before and after the spontaneous breathing trial (SBT). The global LUS scores were derived from the sum of the aeration values from six lung areas; these scores were compared against the weaning outcomes (success vs. failure). The sensitivity, specificity, and area under the curve (AUC) of the prediction modeling were examined. Statistical analysis was done using t -tests, Mann-Whitney U -test, and Chi-square test. P < 0.05 was considered statistically significant. Since values below a P = 0.05 were considered significant.

Out of 124, 73.6% were successful at weaning, while 27.4% failed. The pre-SBT LUS score was higher and statistically significant in a failed group (10 vs. 8, P = 0.008). The post-SBT LUS score demonstrated higher sensitivity in predicting failure (cut-off = 9, sensitivity = 95%, specificity = 66%, AUC = 0.797).

LUS constitutes a noninvasive but valid soothsayer of weaning outcomes in the ICU context. The pre- and post-SBT LUS scores convey important information on lung aeration, which could help develop individualized extubation strategies. Integrating this into standard weaning protocol would maximize outcome benefits, particularly in resource-poor countries.