Lactic acid measurement to identify risk of morbidity from sepsis in pregnancy.

Objective: This study aims to assess the risk of morbidity associated with maternal lactic acid concentration in women with possible sepsis in pregnancy.

Study Design: Retrospective cohort of pregnant and postpartum patients with signs of sepsis. Morbidity outcomes were compared by lactic acid concentration. Linear regression was used to evaluate the association between lactic acid and adverse outcomes.

Results: Out of the 850 women included, 159 had lactic acid measured. Patients with lactic acid measured had higher morbidity: positive blood cultures (16.8 vs. 5.5%, p = 0.04), admission to the intensive care unit (5 vs. 0.1%, p < 0.01) or acute monitoring unit (17.2 vs. 0.9%, p < 0.01), longer hospital stay (median 3 vs. 2 days, p < 0.01), and preterm delivery (18.3 vs. 10.9%, p = 0.05). The mean lactic concentration was higher in patients admitted to the intensive care (2.6 vs. 1.6 mmol/L, p = 0.04) and telemetry unit (2.0 vs. 1.6, p = 0.03), and in those with positive blood cultures (2.2 vs. 1.6, p < 0.01). Lactic acid was positively associated with intensive care or telemetry unit admission, adjusted odds ratio per 1 mmol/L increase in lactic acid 2.34 (95% confidence interval, 1.33-4.12).

Conclusion: Elevated lactic acid in pregnancy is associated with adverse maternal outcomes from presumed sepsis. In this cohort, lactic acid measurement was a marker of more severe infection.