Clinical evidence for respiratory insufficiency type II predicts weaning failure in long-term ventilated, tracheotomised patients: a retrospective analysis

BACKGROUND: Patients who require a prolonged weaning process comprise a highly heterogeneous group of patients amongst whom the outcome differs significantly. The present study aimed to identify the factors that predict whether the outcome for prolonged weaning will be successful or unsuccessful. METHODS: Data from tracheotomised patients who underwent prolonged weaning on a specialised weaning unit were assessed retrospectively via an electronic and paper-bound patient chart. Factors for weaning success were analysed by univariate and multivariate analyses. RESULTS: Out of the 124 patients examined, 48.4% were successfully weaned (n = 60). Univariate analysis revealed that long-term home mechanical ventilation prior to current weaning episode; time between intubation and the first spontaneous breathing trial (SBT); time between intubation and the first SBT of less than 30 days; lower PaCO(2) prior to, and at the end of, the first SBT; and lower pH values at the end of the first SBT were predictors for successful weaning. Following multivariate analysis, the absence of home mechanical ventilation prior to admission, a maximum time period of 30 days between intubation and the first SBT, and a non-hypercapnic PaCO(2) value at the end of the first SBT were predictive of successful weaning. CONCLUSIONS: The current analysis demonstrates that the evidence for respiratory insufficiency type II provided by clinical findings serves as a predictor of weaning failure.