Association of weaning preparedness with extubation outcome of mechanically ventilated patients in medical intensive care units: a retrospective analysis

BACKGROUND: Assessment of preparedness of weaning has been recommended before extubation for mechanically ventilated patients. We aimed to understand the association of a structured assessment of weaning preparedness with successful liberation. METHODS: We retrospectively investigated patients with acute respiratory failure who experienced an extubation trial at the medical intensive care units of a medical center and compared the demographic and clinical characteristics between those patients with successful and failed extubation. A composite score to assess the preparedness of weaning, the WEANSNOW score, was generated consisting of eight components, including Weaning parameters, Endotracheal tube, Arterial blood gas analysis, Nutrition, Secretions, Neuromuscular-affecting agents, Obstructive airway problems and Wakefulness. The prognostic ability of the WEANSNOW score for extubation was then analyzed. RESULTS: Of the 205 patients included, 138 (67.3%) patients had successful extubation. Compared with the failure group, the success group had a significantly shorter duration of MV before the weaning attempt (11.2 ± 11.6 vs. 31.7 ± 26.2 days, p < 0.001), more with congestive heart failure (42.0% vs. 25.4%, p = 0.020), and had different distribution of the types of acute respiratory failure (p = 0.037). The failure group also had a higher WEANSNOW score (1.22 ± 0.85 vs. 0.51 ± 0.71, p < 0.001) and worse Rapid Shallow Breathing Index (93.9 ± 63.8 vs. 56.3 ± 35.1, p < 0.001). Multivariate logistic regression analysis showed that a WEANSNOW Score = 1 or higher (OR = 2.880 (95% CI [1.291–6.426]), p = 0.010) and intubation duration >21 days (OR = 7.752 (95% CI [3.560–16.879]), p < 0.001) were independently associated with an increased probability of extubation failure. CONCLUSION: Assessing the pre-extubation status of intubated patients in a checklist-based approach using the WEANSNOW score might provide valuable insights into extubation failure in patients in a medical ICU for acute respiratory failure. Further prospective studies are warranted to elucidate the practice of assessing weaning preparedness.