NT-proBNP levels during spontaneous breathing test and its association with successful weaning in patients undergoing mechanical ventilation in the intensive care unit

Abstract

Introduction: Weaning of the patient is one of the important medical challenges. One of the most important causes of failure in weaning is cardiovascular disorder. NT-proBNP (N-terminal portion of proBNP) is a specific serum marker for cardiac dysfunction. This study was conducted to evaluate the level of NT-proBNP during the spontaneous breathing test (SBT) in patients undergoing mechanical ventilation in the intensive care unit (ICU) and its association with successful weaning. Methods: In this cross-sectional study, we enrolled 42 intubated patients who were admitted to the ICU ward of Imam Reza hospital and were clinically weaned in 2017. After obtaining informed consent, SBT was started for the patient. One and half hours after SBT onset, a venous blood sample was obtained, the patients were followed for SBT test success, and the results were recorded. Patients were extubated in stabilized condition or continued mechanical ventilation if needed. Finally, the data were analyzed with SPSS v. 16.0 software. Results: SBT was successful in 45.2% of patients. Of all the patients, 54.8% were male. The most common cause of hospitalization was chronic obstructive pulmonary disease (COPD) (35.7%). The mean age of patients with successful SBT was 67.53 ± 6.14 years, and in patients with unsuccessful SBT was 68.70 ± 5.44 years. There was a significant difference between NT-proBNP levels half an hour after SBT between the two groups of patients with successful (7.15 ± 31.18) and unsuccessful (59.61 ± 196.51) SBT. NT-ProBNP changes before and half an hour after SBT in both groups were statistically significant. Conclusion: NT-ProBNP is a predictor criterion of success in weaning of the patients, and as the level of NT-proBNP increases, the rate of failure in weaning increases.