Decannulation criteria in patients with acquired brain injury based on interval forced vital capacity monitoring: a prospective observational study.

OBJECTIVE

Optimized decannulation timing in tracheostomized patients with acquired brain injury (ABI) remains a significant clinical challenge. We examined the association between the 3-week change in forced vital capacity (FVC) and time to successful decannulation, including possible nonlinear threshold effects.

METHODS

This prospective observational cohort study enrolled 56 tracheostomized patients with ABI. FVC was measured at baseline (T0) and at 3 weeks (T1, ΔFVC = FVC_T1 - FVC_T0) using ATS/ERS-compliant spirometry. The primary outcome was time from T0 to successful decannulation (≥72 h without reintubation or reinsertion). Multivariable linear regression, generalized additive models, and threshold effect analysis were performed after adjustment for age, sex, disease duration, diagnosis, and hemiplegic side.

RESULTS

The cohort (N = 56; mean age 51.0 ± 7.6 years; 55.4% male) comprised cerebral infarction (44.6%), cerebral hemorrhage (33.9%), and traumatic brain injury (21.4%). In the adjusted linear model, each 1-L increase in ΔFVC was associated with 8.7 days shorter time to decannulation (β = -8.677 days/L, 95% CI: -12.399 to -4.955, p < 0.001). A threshold effect was identified at ΔFVC = 0.52 L: below this threshold, the association was pronounced (β = -13.616 days/L, p < 0.001); above it, the association was attenuated and non-significant (β = -2.244 days/L, p = 0.492).

CONCLUSION

Interval FVC monitoring may serve as a practical adjunct in decannulation assessment. A ΔFVC of 0.52 L or greater may serve as a clinically useful reference point for initiating comprehensive decannulation evaluation in patients with ABI undergoing pulmonary rehabilitation. This threshold should be interpreted cautiously and validated in larger multicenter studies.