Plasma levels of pro-atrial natriuretic peptide, pro-adrenomedullin, and pro-endothelin-1 correlate with the severity of organ dysfunction in critically ill patients

Introduction

Prohormones of cardiovascular active mediators may add important information to the clinical status of patients with systemic inflammation. However, only little information is available of how serum levels of such prohormones are affected by the clinical status of critically ill patients. The goal of this study was to identify factors that independently influence prohormone plasma concentrations in an ICU setting.

Methods

Citrate plasma samples of 185 patients with either severe sepsis/septic shock (n = 120) or systemic inflammatory response syndrome (SIRS, n = 65) after coronary bypass surgery have been obtained daily, resulting in 2385 samples. The Sequential Organ Failure Assessment (SOFA) score was also determined daily. Midregional pro-atrial natriuretic peptide (MR-proANP), midregional pro-adrenomedullin (MR-proADM), and C-terminal pro-endothelin-1 (CT-proET-1) have been measured by an immunoassay (BRAHMS AG, Germany). For each patient, the maximum values of MR-proANP, MR-proADM and CT-proET-1 were identified. These maximum levels were analyzed with multiple regression using demographic parameters and parameters of inflammation (leukocytes [WBC], C-reactive protein [CRP], procalcitonin) as well as the SOFA score as independent factors.

Results

The mean age was 63.5 years. The mortality rate was 27% at a mean APACHE II score of 17.5. Table 1 presents individual regression coefficients if statistically significant. CRP levels did not correlate with any of the measured prohormones.

Table 1 (abstract P196)

Conclusion

Variations in the levels of measured prohormones are only slightly affected by parameters of inflammation. However, development of organ dysfunction is well reflected by proANP and MR-proADM but only to a lesser degree by CT-proET-1.