In the assessment and management of septic patients in the emergency department (ED), serum lactate is often measured to stratify severity to guide decision making. Increased adrenergic drive has been postulated as a contributory factor for hyperlactatemia in sepsis. We aim to prospectively evaluate the effect of chronic beta-blocker use on serum lactate levels in sepsis at initial presentation to the ED.

We conducted a prospective observational study at the ED of a tertiary care academic medical center in Singapore. One hundred and ninety-five ED patients who fulfilled all of the following: (1) age 45 years and above, (2) tympanic temperature ≥ 37.8 °C or clinically suspected to have an infection, and (3) quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) score ≥ 1 were included in the study. Serum venous lactate was sampled within two hours from presentation to the ED. The primary outcome measure was the difference in initial serum venous lactate concentration at presentation to the ED in patients on chronic beta-blockers versus patients without.

Seventy patients (35.9%) were on long-term beta-blocker therapy. The primary outcome of mean initial serum venous lactate concentration was similar between patients prescribed chronic beta-blocker therapy and patients without (1.78 mmol/L versus 1.70 mmol/L, p = .540). Chronic beta-blocker therapy also did not significantly affect mean initial serum venous lactate concentration across all subgroups of sepsis risk stratification.

Long-term beta-blocker therapy did not significantly affect initial serum venous lactate concentration in ED patients with suspected sepsis.