RESUMO
OBJECTIVES: We aimed to establish new cut-off values for SIRS (Systemic Inflammatory Response Syndrome) variables in the obstetric population. METHODS: A prospective cohort study in pregnant and postpartum women admitted with systemic infections between December 2017 and January 2019. Patients were divided into three cohorts: Group A, patients with infection but without severe maternal outcomes (SMO); Group B, patients with infection and SMO or admission to the intensive care unit (ICU); and Group C, a control group. Outcome measures were ICU admission and SMO. The relationship between SIRS criteria and SMO was expressed as the area under the receiver operating characteristics curve (AUROC), selecting the best cut-off for each SIRS criterion. RESULTS: A total of 541 obstetric patients were enrolled, including 341 with infections and 200 enrolled as the reference group (Group C). The patients with infections included 313 (91.7%) in Group A and 28 (8.2%) in Group B. There were significant differences for all SIRS variables in Group B, compared with Groups A and C, but there were no significant differences between Groups A and C. The best cut-off values were the following: temperature 38.2 °C, OR 4.1 (1.8-9.0); heart rate 120 bpm, OR 2.9 (1.2-7.4); respiratory rate 22 bpm, OR 4.1 (1.6-10.1); and leukocyte count 16,100 per mcl, OR 3.5 (1.6-7.6). CONCLUSIONS: The cut-off values for SIRS variables did not differ between healthy and infected obstetric patients. However, a higher cut-off may help predict the population with a higher risk of severe maternal outcomes.