The Additional Prognostic Value of Serial Biomarker Measurements for Extubation Failure Among Patients With COVID-19 Acute Respiratory Distress Syndrome.

Background: Extubation failure is associated with adverse outcomes in critically ill patients. While single biomarker measurements can aid prediction, repeated biomarker measurements can help to timely recognize underlying diseases. Objectives: The aim of this study was to investigate the temporal evolution of cardiac (N-terminal pro-B-type natriuretic peptide [NT-proBNP], high-sensitivity troponin T [Hs-TnT]) and inflammatory biomarkers (interleukin-6 [IL-6] and procalcitonin [PCT]) prior to extubation and determine their additional prognostic value. Design: Retrospective cohort study. Methods: Patients with COVID-19 extubated after mechanical ventilation were included. Daily biomarker levels were collected up to 3 days before extubation. The primary endpoint was extubation failure, defined as reintubation or death within 7 days. Linear mixed-effect models were used to analyze biomarker trajectories in patients with extubation success and failure. Each day before extubation a logistic regression model (consisting of the 4 biomarkers) was constructed to determine the model with the best discriminative ability. Results: Among 297 patients, 21.5% experienced extubation failure. Log2 Hs-TnT, NT-proBNP and PCT were higher on all days in patients with extubation failure (P < .001, P = .01, P = .01, respectively), whereas log2 IL-6 was not (P = .54). There was no difference in the change of biomarkers over the days between patients with extubation success and failure (P-value for interaction = .11, P = .82, P = .31, P = .84, respectively). The performance of the logistic regression model including the 4 biomarkers on the day of extubation was significantly better than the model 3 days before extubation (AUC 0.71, 95% CI: 0.64-0.79 vs AUC 0.66, 95% CI: 0.58-0.73, P = .03). Conclusion: Hs-TnT, NT-proBNP and PCT measured on the days before extubation are consistently higher in patients with extubation failure. However, there was no relation between the change in biomarker levels over time and extubation outcome. The serial assessment of Hs-TnT, NT-proBNP, PCT, and IL-6 do not seem to add prognostic information to predict extubation failure.