N-terminal pro-B-type natriuretic peptide for predicting fluid challenge in patients with septic shock.

ABSTRACT

BACKGROUND: The aim of this study is to examine whether plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration could predict fluid responsiveness in septic shock patients following fluid challenge (FC). METHODS: We reviewed prospectively collected data from 79 septic shock patients who received invasive cardiac output (CO) monitoring following a 500 mL FC. Haemodynamics were recorded, and blood sampling for NT-proBNP values was performed. Patients were divided into responders and non-responders according to fluid responsiveness, which was defined as cardiac index (CI) increase ≥10% induced by FC. The NT-proBNP and the CI changes were analysed using Pearson correlation. The area under the curve (AUC) for NT-proBNP was used to test its ability to distinguish responders and non-responders. Subgroup analyses were also explored. RESULTS: Among 79 patients, there were 55 responders. High NT-proBNP values were common in the study cohort. Baseline NT-proBNP values were comparable between responders and non-responders. In general, NT-proBNP values were not significantly correlated with CI changes after FC (r=-0.104, P=0.361). Similarly, the NT-proBNP baseline values could not identify responders to FC with an AUC of 0.508 (95% confidence interval, 0.369-0.647). This result was further confirmed in the subgroup analyses. CONCLUSIONS: Baseline NT-proBNP concentration value may not serve as an indicator of fluid responsiveness in patients with septic shock and should not be an indicator to withhold fluid loading.