- Poster presentation
- Open Access
Predictive value of tissue oxygen saturation upon mortality in Emergency Department patients with sepsis
© Vorwerk and Coats 2011
- Published: 1 March 2011
- Emergency Department
- Septic Shock
- Severe Sepsis
- Emergency Department Patient
- Tissue Oxygen Saturation
Microvascular dysfunction and inadequate delivery of oxygen to the tissues is a feature of septic shock. The degree of this microcirculatory impairment has not been assessed in the early phases of Emergency Department (ED) sepsis management. The purpose of this study was to assess the relationship between tissue oxygen saturation (StO2) and conventional vital signs and in-hospital mortality for ED patients with severe sepsis or septic shock.
Prospective cohort study of adult ED patients with severe sepsis or septic shock. Standard vital signs were monitored in all patients. StO2 measurements using near-infrared spectroscopy were commenced as soon as possible after the patients' arrival in the ED. The measurements were continued throughout the stay in the ED whilst receiving normal treatment. StO2 readings were repeated after 24 hours of sepsis management. All patients were followed up for 30 days.
Forty-nine patients were included in this study, of which 24 (49%) died. Nonsurvivors were significantly older than survivors (79 vs. 64, P = 0.008) but there were no significant differences in co-morbidities or conventional vital signs. On arrival in the ED there was no difference in mean StO2 between survivors and nonsurvivors (72% vs. 72%, P = 0.97). With treatment, StO2 improved significantly to 78% (P = 0.006) in survivors but remained persistently low in nonsurvivors. The AUROC for StO2 was 0.63 on ED departure and 0.71 after 24 hours of treatment, performing far better than heart rate (0.53), SpO2 (0.50) and systolic blood pressure (0.51). There was no correlation between StO2 and any of the routine vital signs.
Our results demonstrate that a consistently low tissue oxygen saturation despite initial sepsis resuscitation is associated with an increased in-hospital mortality. We have further shown that tissue oxygen saturation is a better prognostic indicator than conventional vital signs in severely septic ED patients.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.