The effect of the physiological reserve surrogate characteristics on non-airway extubation failure in patients with pneumonia with high Burns wean assessment program scores

Abstract

Objectives: A successful weaning prediction score could be a useful tool to predict non-airway extubation failure. However, it may carry some challenges without considering the effect of the physiological reserve on the sustainability of extubation. This study investigated the possible correlation between the physiological reserve surrogate characteristics including acute, baseline, and biochemical patients’ factors and non-airway extubation failure in patients with pneumonia. Methods: A retrospective cohort study at two academic teaching hospitals was conducted between January 2019 and January 2020 with patients with pneumonia requiring invasive mechanical ventilation and with Burns Wean Assessment Program (BWAP) scores equal to or exceeding 50. Acute clinical, biochemical, and baseline characteristics were collected for both successful and failed non-airway extubation patients. Results: Among 313 patients, the mean age was 63.63 ± 10.44 years and most of the patients were males (60.7%). The median invasive mechanical duration was 7 days [Interquartile range (IQR): 5–12], the median length of ICU stay was 12 [IQR: 6–23] and the in-hospital mortality was 16.9%. Among this cohort of patients with pneumonia, 37.7% had non-airway extubation failure. Multivariate logistic regression analyses showed that higher CURB-65 score, longer duration of invasive mechanical ventilation, hemodynamic instability, healthcare-associated pneumonia, older men, history of diabetes mellitus, history of cardiac disease, hypophosphatemia, hypocalcemia, and higher admission serum sodium were associated with increased risk of non-airway extubation failure in patients with pneumonia with high BWAP score. Conclusion: A distinct successful weaning score for patients with pneumonia that considers patients’ acute clinical, biochemical, and baseline characteristics may be effective, and these factors could be reflective of the underlying physiological reserve. Sustainability score from IMV rather than weaning score is needed and may be more predictive for the extubation outcome.