Earliest Bedside Assessment of Hemodynamic Parameters and Cardiac Biomarkers: Their Role as Predictors of Adverse Outcome in Patients with Septic Shock.

BACKGROUND

Early assessment and aggressive hemodynamic treatment have been shown to increase the survival of patients in septic shock. Current and past sepsis guidelines recommend a resuscitation protocol including central venous pressure (CVP), mean arterial blood pressure (MAP), urine output and central venous oxygen saturation (ScvO2) for resuscitation within the first six hours. Currently, the established severity score systems like APACHE II score, SOFA score or SAPS II score predict the outcome of critically ill patients on the bases of variables obtained only after the first 24 hours. The present study aims to evaluate the risk of short-term mortality for patients with septic shock by the earliest possible assessment of hemodynamic parameters and cardiac biomarkers as well as their role for the prediction of the adverse outcome.

METHODS

52 consecutive patients treated for septic shock in the intensive care unit of one centre (Marien Hospital Herne, Ruhr University Bochum, Germany) were prospectively enrolled in this study. Hemodynamic parameters (MAP, CVP, ScvO2, left ventricular ejection fraction, Hematocrit) and cardiac biomarkers (Troponin I) at the ICU admission were evaluated in regard to their influence on mortality. The primary endpoint was all-cause mortality within 28 days after the admission.

RESULTS

A total of 52 patients (31 male, 21 female) with a mean age of 71.4±8.5 years and a mean APACHE II score of 37.0±7.6 were enrolled in the study. 28 patients reached the primary endpoint (mortality 54%). Patients presenting with hypotension (MAP <65 mmHg) at ICU admission had significantly higher rates of 28-day mortality as compared with the group of patients without hypotension (28-day mortality rate 74 % vs. 32 %, p<0.01). Furthermore, the patients in the hypotension present group had significantly higher lactate concentration (p=0.002), higher serum creatinin (p=0.04), higher NTproBNP (p=0.03) and after the first 24 hours higher APACHE II scores (p=0.04). A MAP <65 mmHg was the only hemodynamic parameter significantly predicting the primary endpoint (OR: 4.1, CI: 1.1 - 14.8, p=0.008), whereas the remaining hemodynamic variables CVP, ScvO2, Hematocrit, Troponin I and left ventricular ejection fraction (LVEF) seemed to have no influence on survival. Besides, non-survivors had a significantly higher age (74.1±9.0 vs. 68.4±6.9, p=0.01). If hypotension coincided with an age ≥72 years, the 28-day mortality rate escalated to 88%.

CONCLUSIONS

In our study, we identified a risk group with an exceedingly high mortality rate: the patients with an age ≥72 years and presenting with hypotension (MAP <65 mmHg). These data can be easily obtained at the time of the very first patient contact. As a result, an aggressive and a more effective treatment can be initiated within the first minutes of the primary care, possibly reducing organ failure and short-term mortality in this risk group.