Endothelial dysfunction is thought to be an important mechanism of organ failure in sepsis. We hypothesised that endothelial function (EF) would be impaired in adult patients with sepsis; that it would improve with treatment; and that the degree of its impairment would correlate with disease severity and outcome.
EF was measured using a novel, noninvasive technique at the bedside (reactive hyperaemia peripheral arterial tonometry (RH-PAT)) in three groups: patients with sepsis requiring admission to the ICU (ICU sepsis); patients with sepsis requiring hospital but not ICU admission (ward sepsis); and control patients without sepsis. Measurements were taken on days 0, 2 and 7 in the sepsis patients and at baseline in the control patients.
Planned interim analysis was performed on 38 ICU sepsis patients, 19 ward sepsis patients and 28 control patients. The mean (95% CI) baseline RH-PAT index was significantly lower in ICU sepsis (1.56 (1.41–1.71)) than in control patients (2.03 (1.87–2.19)), P = 0.0001. It was intermediate in the ward sepsis group: baseline RH-PAT index = 1.72 (1.52–1.92) (P = 0.02 cf controls, not significant cf ICU sepsis). See Figure 1. The RH-PAT index improved markedly in the ward sepsis patients over the first 2 days (1.72 (1.52–1.92) to 2.29 (2.08–2.57); P = 0.0004); however, it did not change significantly in the ICU sepsis patients (1.56 (1.41–1.71) to 1.77 (1.56–1.98)).
Noninvasive measurement of EF is feasible in sepsis. EF in sepsis is initially markedly impaired. It improves over the first 2 days in those patients with moderate sepsis but not in those with sepsis requiring ICU admission. These data will be further analysed to explore correlations, and blood samples have been stored for the measurement of serum arginine and markers of endothelial activation.