The correlation between brain natriuretic peptide and invasive hemodynamic parameters and their value in prognosis of patients with noncardiac shock

Abstract

To examine the correlation between the plasma level of brain natriuretic peptide (BNP) and the hemodynamic parameters collected through Swan-Ganz flowing balloon catheter procedure in patients with noncardiac shock, in order to evaluate the potential for BNP to be used as prognostic indicator. The plasma BNP and invasive hemodynamic parameters data [central venous pressure (CVP), pulmonary arterial pressure (PAP), pulmonary capillary wedge pressure (PCWP), and cardiac output (CO)] were collected from 21 noncardiac shock patients received Swan-Ganz catheterization throughout a continuous surveillance for 3 days. The BNP, CVP, PAP, PCWP, CO in survivors (n = 8) and non-survivors (n = 13) were compared and the correlation between the value of BNP and the invasive hemodynamic parameters were analyzed using multiple regression. The mean value of BNP (ng/L) was significantly higher in non-survivors (708.06 ± 242.58 vs. 317.05 ± 140.21, P < 0.05). In day 1, no significant difference was found in any hemodynamic parameters between non-survivors and survivors. But in day 3, the non-survivors were found to have significantly higher CVP (mm Hg, 1 mm Hg = 0.133 kPa: 13.64 ± 4.00 vs. 9.92 ± 1.26, P < 0.05) and lower CO (L/min: 4.61 ± 2.06 vs. 6.95 ± 1.28, P < 0.05). The differences in PAP (mm Hg: 20.84 ± 8.48 vs. 16.82 ± 4.97) and PCWP (mm Hg: 13.60 ± 5.71 vs. 12.72 ± 4.98) remained insignificant (both P > 0.05) between the two groups. The correlation between BNP and the invasive hemodynamic parameters was modest there was no correlation between BNP and CVP, PAP, PCWP, CO (r = 0.157, 0.306, 0.229, -0.269, P = 0.16, 0.25, 0.09, 0.12). In patients with shock, both plasma BNP and invasive hemodynamic examination showed certain prognostic value. But in noncardiac shock cases, the increased BNP did not correlate with heart function, therefore it could not replace the Swan-Ganz catheter data to guide the treatment in these patients.