Clinical assessment indicators of postpartum hemorrhage: A systematic review

Objective: The assessment indicators of postpartum hemorrhage (PPH) were systematically reviewed to explore their relationship with blood loss as an early warning sign to identify potential PPH for prompt intervention. Methods: A systematic literature search of 9 databases was conducted according to inclusion and exclusion criteria using a comprehensive strategy. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) strategy was chosen as the tool for quality assessment of included studies, and data concerning the basic study characteristics and assessment indicators were extracted. Results: Eleven studies were included in this review. The assessment indicators in different reports covered heart rate, blood pressure, placental and birth canal check, hemoglobin (Hb), hematocrit (HCT), coagulation function tests, hemodynamic parameters and arterial blood gas, but no data on the assessment of postpartum uterine contraction were found. The relationship between indicators and blood loss varies. The overall quality of 9 manuscripts was comparatively high or moderate, and 2 were rated as low. Conclusions: The association between blood loss and clinical symptoms is not conclusive based on the present studies, and specific cut-off points could not be formulated to determine the approximate amount of blood loss. However, some cut-off points can be considered warning signs for the need of advanced interventions, such as heart rate, prothrombin time, and placental implantation. Further research on comprehensive assessment and cut-off points should be performed such that birth attendants can distinguish PPH as early as possible. Keywords: Clinical indicator, Postpartum assessment, Postpartum hemorrhage, Blood loss, Early warning, Systematic revie