Effectiveness of arterial, venous, and capillary blood lactate as a sepsis triage tool in ED patients.

OBJECTIVE: We evaluate the capacity of arterial (ABL), peripheral venous (VBL), and capillary (CBL) blood lactate concentration to early detect the presence of severe sepsis in patients admitted to the emergency department for a septic syndrome.

METHODS: Patients with signs of sepsis presenting to the emergency department were prospectively enrolled. Blood lactate was measured using a handheld point-of-care analyzer on microsamples of arterial, peripheral venous, and capillary blood. An arterial blood sample was dispatched to the central laboratory as a reference measurement.

RESULTS: A total of 103 patients were enrolled in the study, with 63 patients presenting with a severe sepsis. There was a strong correlation between the point of care and the reference blood lactate measurement. The CBL, VBL, and ABL were all significantly different (3.01±0.29, 2.51±0.21, and 2.03±0.18 mmol/L, respectively; P<.001). The VBL value was the most efficient to detect early the presence of severe sepsis (areas under the receiver operating characteristic curves were 0.85±0.04, 0.76±0.05, and 0.75±0.05 for VBL, ABL, and CBL, respectively; P<.01). Mortality at 28 days was related to the severity of sepsis (28.6% vs 7.5%) and to the number or organ dysfunctions (P<.01). Arterial blood lactate, VBL, and CBL were all significantly associated with the 28th-day mortality.

CONCLUSIONS: Initial VBL may be used efficiently to assess the severity of sepsis, and it could even be more effective than ABL and CBL to early detect the presence of severe sepsis.