Tranexamic Acid Use Amongst Women at High Versus Low Risk of Post-partum Haemorrhage Delivering at Kenyatta National Hospital: a Retrospective Cohort Study

Abstract

Background: Post-partum haemorrhage (PPH) tops the list amongst causes of maternal deaths globally. PPH accounts for approximately one in every four pregnancy-and-childbirth-related deaths that occur globally and remains the leading cause in most low- and middle-income countries. In Kenya, it accounts for 44% of maternal mortalities. The World Health Organization (WHO) recommends the Active Management of Third Stage of Labour (AMSTL) package as a post-partum haemorrhageprevention strategy. Among the components of AMSTL, the use of uterotonics is proposed to be the main intervention. Oxytocin remains the main uterotonic for preventing primary postpartum haemorrhage in both cesarean, other operative, and vaginal deliveries. Intravenous Tranexamic Acid (TXA), an antifibrinolytic agent that prevents plasminogen from being activated to plasmin, has recently been recommended by WHO for use in treatment of all PPH cases, regardless of the cause, and this is the practice in our setting. Whether or not TXA can be used prophylactically in obstetric setting remains unclear due to limitation of data from either retrospective studies and/or clinical trials given that it has largely been studied in surgical set-ups rather than obstetric. Studying the patterns of use of TXA amongst different obstetric groups from available data therefore becomes a necessary step that will inform future trials that may wish to investigate prophylactic use of TXA amongst different obstetric groups to prevent PPH. Objective: To determine the association between the presence of risk factors for postpartum haemorrhage at the time of birth and use of tranexamic acid among parturients at Kenyatta National Hospital. Methodology: This was a retrospective cohort study of in which 437 files randomly selected out of those who delivered at Kenyatta National Hospital maternity between January and December 2019. The study assessed the incidence of TXA use, use of additional uterotonics, blood transfusion, additional surgical interventions, and ICU/HDU admission between the women with risk factors for PPH (exposed) and those without (unexposed). Their records were retrieved and information on their socio-demographics, PPH-risk-factor status, use of Tranexamic acid, additional management for PPH, and the maternal outcomes were obtained and documented. The data was cleaned, analyzed and managed using STATA. Crude and adjusted Relative Risk (RR) was used to assess the association between the different variables and risk factors. A P-value of <0.05 was considered to be statistically significant.

Study Significance: This study addsto the available pool, valuable information on the use of TXA amongst women with high risk of PPH. This will inform future clinical trials that would want to look into the possible use of TXA prophylactically in obstetric settings. Results: 437 participants who were eligible were recruited into the study, and 222 were exposed, while 215 were allocated to the control group. The mean age was 29yrs (30 vs 28 for Exposed vs Unexposed). TXA use was found to be higher in those with risk factors (11.24%) than those without (3.72%) (RR 3.026, P-value 0.003) but not of statistical significance after adjusting for confounders. A similar pattern was observed in the use of additional Uterotonics, blood products and HDU/ICU admission between the two groups. Surgical interventions were observed to be less in the exposed (3.15%) than in the unexposed (7.98%) group(RR 0.395, P-value 0.022). Recommendation: We recommend for additional studies, preferably randomized trials, to look prospectively into the prophylactic of use TXA among those having PPH risk factors.