Early prognostic capacity of serum lactate for severe postpartum hemorrhage

Objective To evaluate whether the concentration of serum lactate during the diagnosis of postpartum hemorrhage (bleeding >= 500 mL during labor or >= 1000 mL during cesarean delivery) predicts severe hemorrhage (SPPH; blood loss >= 1500 mL at end of labor or in the following 24 h). Methods A prospective cohort pilot study was conducted of women with a vaginal or cesarean delivery from February 2018 to March 2019 who presented with bleeding >= 500 mL measured by the gravimetric method in a reference hospital in San Luis Potosi, Mexico. Venous blood samples were taken for analysis of serum lactate. A receiver operating characteristic curve determined the serum lactate threshold value for SPPH and chi(2) test assessed the difference in serum lactate elevation between SPPH and non-SPPH groups. Lastly, the prognostic capacity between the thresholds was compared. Results SPPH developed in 43.33% of the 30 women in the study group. The best prognostic threshold was 2.68 mmol/L of serum lactate (odds ratio [OR] 17.88, 95% confidence interval [CI] 2.7-16.8, P < 0.001); sensitivity was 0.85 (95% CI 0.55-0.98); specificity was 0.76 (95% CI 0.50-0.93). Conclusion Serum lactate may be a useful prognostic marker for SPPH, more studies are needed to validate these findings.

Automated summary

The study suggests that serum lactate concentration may predict severe postpartum hemorrhage, with a threshold value of 2.68 mmol/L showing good sensitivity and specificity for this purpose. Further studies are needed to confirm these findings.