Methods
A prospective cohort study was carried out from February 2020 to March 2021 in which were included pregnant women with postpartum haemorrhage (≥500ml in labour or ≥1000ml in c-section, Institutional definition of postpartum haemorrhage) in a reference hospital in San Luis Potosi Mexico (Hospital Central Dr. Ignacio Morones Prieto). The study obtained approval from the Institutional Ethical Committee (Registration number 93-19)
We included Pregnant patients in labour or cesarean section with postpartum haemorrhage, without conditions that might elevate lactate concentration such as eclampsia, leukaemia, lymphoma, and solid tumours, poorly controlled diabetes, liver failure, and ingestion of antiretroviral drugs and biguanides, confirmed sepsis or diagnosed with severe shock or documented anaemia at the beginning of the study, Patients who decided to withdraw their consent or to leave the study were eliminated. Bleeding volume was calculated by the gravimetric method as described here, blood-Stained Surgical Gauzes from delivery or c-section were weighed, and its dry weight was subtracted from the total blood-stained weight. Blood weight (g) was converted into blood volume (ml) using the accepted approximation of blood density of 1 g = 1mL. At the diagnosis of postpartum haemorrhage (≥500ml in labour or ≥1000ml in c-section, Institutional definition of postpartum haemorrhage), Capillary lactate and haemoglobin were determined by bedside equipment Acutrend plus©, and Shock index was calculated as the heart rate (HR) divided by systolic blood pressure (SBP). These parameters were also measured at 15 and 30 minutes after the diagnosis.