BACKGROUND

A variety of parameters and diaphragmatic ultrasound in ventilator weaning has been studied extensively, and the findings yield inconsistent conclusions. The parasternal intercostal muscle holds important substantial respiratory reserve capacity when the central drive is enhanced, the predictive value of combining parasternal intercostal muscle ultrasound parameters with P0.1(airway occlusion pressure at 100 msec) in assessing ventilator weaning outcomes is still unknown.

OBJECTIVES

Our study aimed to evaluate the predictive efficacy of parasternal intercostal muscle ultrasound in conjunction with P0.1 in determining weaning failure.

METHODS

We recruited patients who had been admitted to ICU and had been receiving mechanical ventilation for over two days. All patients underwent a half-hour spontaneous breathing trial (SBT) with low-level pressure support ventilation (PSV). They were positioned semi-upright for parasternal intercostal muscle ultrasound evaluations, including parasternal intercostal muscle thickness (PIMT), and parasternal intercostal muscle thickening fraction (PIMTF); P0.1 was obtained from the ventilator. Weaning failure was defined as the need for non-invasive positive pressure ventilation or re-intubation within 48 h post-weaning.

RESULTS

Of the 56 enrolled patients with a mean age of 63.04 ± 15.80 years, 13 (23.2%) experienced weaning failure. There were differences in P0.1 (P = .001) and PIMTF (P = .017) between the two groups, but also in patients with a diaphragm thickness ≥ 2 mm. The predictive threshold values were PIMTF ≥ 13.15% and P0.1 ≥ 3.9 cmHO for weaning failure. The AUROC for predicting weaning failure was 0.721 for PIMTF, 0.792 for P0.1, and 0.869 for the combination of PIMTF and P0.1.

CONCLUSIONS

The parasternal intercostal muscle thickening fraction and P0.1 are independently linked to weaning failure, especially in patients with normal diaphragm thickness. The combination of parasternal intercostal muscle thickening fraction and P0.1 can serve as a valuable tool for the precise clinical prediction of weaning outcomes.

TRIAL REGISTRATION

Chinese Clinical Trial Registry website (ChiCTR2200065422).