07 Aug 09
By R Jarai, B Fellner, D Haoula, N Jordanova, G Heinz, G Karth, K Huber, A Geppert
Crit Care Med 2009;37:1837-1844
Plasma N-terminal pro-B-type natriuretic peptide (Nt-pro-BNP) levels are frequently elevated in critically ill patients and are associated with an increased mortality. In this study, we determined Nt-pro-BNP levels in patients with cardiogenic shock (CS) and evaluated its association with clinical and hemodynamic parameters and 30-day mortality.
Two, eight-bed intensive care units at a university and a community hospital.
Retrospective study on stored plasma samples of 58 patients with CS, obtained at admission to the intensive care unit.
Measurements and main results
Massively elevated Nt-pro-BNP concentrations showed no significant association with duration of shock, total Sequential Organ Failure Assessment score, or invasive hemodynamic parameters at the time of blood sampling but a significant association with estimated glomerular filtration rate (p < 0.001), C-reactive protein (p = 0.03), age (p = 0.005), and body weight (p = 0.03). Both in univariate and multivariate survival analyses, Nt-pro-BNP levels above the median (>12,782 pg/mL) were significant predictors of 30-day mortality (p < 0.001) and showed a complementary role with interleukin (IL)-6 in predicting outcome. Patients with IL-6 >195 pg/mL and Nt-pro-BNP above the median value had the highest 30-day mortality (93.7%), whereas patients with lower IL-6 levels together with lower Nt-pro-BNP levels had significantly better survival (mortality rate 26.3%). Among patients who had acute myocardial infarction, those with Nt-pro-BNP concentrations above the median level showed a highly impaired clinical course even if coronary revascularization was successful (30-day mortality 90.9% vs. 29.4%, p = 0.001), whereas survival of patients with unsuccessful revascularization did not differ significantly with respect to the median of Nt-pro-BNP (30-day survival rate 81.8% vs. 75.0%, p = 0.71).
The massive elevations of Nt-pro-BNP observed in the early phase of CS seem to be independent of ventricular performance. Nt-pro-BNP levels are nevertheless predictive of 30-day survival in patients with CS especially in those with successful revascularization and might be used in combination with IL-6 for estimation of outcome early on.
22 Jan 09
By R Cavallazzi, A Nair, T Vasu and P E Marik
Intensive Care Med 2008:34;2147-2156
Patients with pulmonary embolism (PE) have a high risk of death, and it is important to recognize factors associated with higher mortality. Recently, several biomarkers have been studied for risk stratification in patients with PE.
Evaluate the available evidence on (a) the accuracy of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) for the diagnosis of right ventricular dysfunction and (b) their value as a prognostic factor of all-cause in-hospital or short-term mortality in patients with PE.
MEDLINE, Embase, and citation review of relevant primary and review articles.
Selection criteria We selected studies evaluating the accuracy of BNP or NT-proBNP for the diagnosis of right ventricular dysfunction. We also selected studies that reported data on BNP or NT-proBNP as a predictor of short-term mortality in patients with PE.
Sixteen studies met our inclusion criteria. The pooled diagnostic odds ratio for the diagnosis of right ventricular dysfunction in pulmonary embolism was 39.45 (95% CI; 15.54ñ100.12) and 24.73 (95% CI 2.02ñ302.37) for BNP and NT-proBNP, respectively. The pooled odds ratio for all-cause in-hospital or short-term mortality was 6 (95% CI 1.31±27.43; p: 0.021) and 16.12 (95% CI 3.1±83.68; p: 0.001) for BNP (cutoff: 100 pg/ml) and NT-proBNP (cutoff: 600 ng/L), respectively.
The results of this meta-analysis indicate that BNP and NT-proBNP are associated with the diagnosis of right ventricular dysfunction (RVD) in patients with an acute PE and are significant predictors of all-cause in-hospital or short-term mortality in these patients.
15 Nov 08
By C Kirchhoff, BA Leidel, S Kirchhoff, V Braunstein, V Bogner, U Kreimeier, W Mutschler and P Biberthaler
Critical Care 2008;12:R118
Increased serum B-type natriuretic peptide (BNP) has been identified for diagnosis and prognosis of impaired cardiac function in patients suffering from congestive heart failure, ischemic heart disease, and sepsis. However, the prognostic value of BNP in multiple injured patients developing multiple organ dysfunction syndrome (MODS) remains undetermined. Therefore, the aims of this study were to assess N-terminal pro-BNP (NT-proBNP) in multiple injured patients and to correlate the results with invasively assessed cardiac output and clinical signs of MODS.
Twenty-six multiple injured patients presenting a New Injury Severity Score of greater than 16 points were included. The MODS score was calculated on admission as well as 24, 48, and 72 hours after injury. Patients were subdivided into groups: group A showed minor signs of organ dysfunction (MODS score less than or equal to 4 points) and group B suffered from major organ dysfunction (MODS score of greater than 4 points). Venous blood (5 mL) was collected after admission and 6, 12, 24, 48, and 72 hours after injury. NT-proBNP was determined using the Elecsys proBNP® assay. The hemodynamic monitoring of cardiac index (CI) was performed using transpulmonary thermodilution.
Serum NT-proBNP levels were elevated in all 26 patients. At admission, the serum NT-proBNP values were 116 ± 21 pg/mL in group A versus 209 ± 93 pg/mL in group B. NT-proBNP was significantly lower at all subsequent time points in group A in comparison with group B (P < 0.001). In contrast, the CI in group A was significantly higher than in group B at all time points (P < 0.001). Concerning MODS score and CI at 24, 48, and 72 hours after injury, an inverse correlation was found (r = -0.664, P < 0.001). Furthermore, a correlation was found comparing MODS score and serum NT-proBNP levels (r = 0.75, P < 0.0001).
Serum NT-proBNP levels significantly correlate with clinical signs of MODS 24 hours after multiple injury. Furthermore, a distinct correlation of serum NT-proBNP and decreased CI was found. The data of this pilot study may indicate a potential value of NT-proBNP in the diagnosis of post-traumatic cardiac impairment. However, further studies are needed to elucidate this issue.
06 Nov 08
By F Post, L Weilemann, C-M Messow, C Sinning, T Munzel
Crit Care Med 2008;36:3030-3037
In early stages of septic shock, impaired myocardial function plays an important prognostic role. In this context, B-type natriuretic peptide (BNP) has been shown to be a neurohumoral marker for left ventricular dysfunction, because myocardial strain and ischemia both increase BNP concentration. The present study was designed to test if BNP allows for identification of patients at risk for developing sepsis-induced myocardial depression and if an increased concentration of BNP is associated with an adverse outcome in patients with septic shock.
Methods and Results
In a prospective study, 93 patients with septic shock were divided into one group with normal ventricular function (left ventricular ejection fraction >50%) on days 3 to 5 (n = 38) and another group of patients with impaired left ventricular function (left ventricular ejection fraction <50%) on days 3 to 5 (n = 55). Patients with impaired left ventricular function had an increased median plasma BNP concentration on day 5 (699 [608 of 795.5] pg/nL vs. 86 [71.3 of 93] pg/nL) and an ejection fraction of 38 +/- 6% on day 5 vs. 58 +/- 7% in patients without impaired left ventricular function. There was a close inverse relation between increased plasma BNP concentrations and depressed left ventricular ejection fraction (p < 0.05). BNP measured at days 3 and 5 revealed an association with the end point of survival. In the proportional hazards regression model adjusted for age, male gender, and creatinine concentration, measured at days 0, 3, 5, and 12, BNP concentration at day 5 showed an increased hazard for reaching the end point (hazard ratio: 1.407; 95% confidence interval: 1.033-1.916; p = 0.030). In an additional receiver operating characteristic curve analysis, the predictive value of a model including cardiovascular risk factors and additional BNP concentration on day 5, compared with a baseline model of cardiovascular risk factors, improved the area under the curve the most; therefore, this model was suited best for prediction of sepsis-induced myocardial depression and 30-day survival for patients with septic shock. Area under the curve of this model combined with BNP concentration at day 5 for death after 30 days (0.65) impaired left ventricular ejection fraction (0.94) and sepsis-induced myocardial depression (0.96).
These results indicate that plasma BNP concentration represents a reliable marker for identification of patients developing sepsis-induced myocardial depression. In addition, BNP concentration on day 5 may be used as a prognostic marker to identify patients with an elevated risk for an adverse outcome.