TeMpOH-study

Introduction

The TeMpOH-studies intend to improve guidelines on massive transfusion in women suffering from major obstetric hemorrhage (MOH). TeMpOH-1 is an observational study among women who received fresh frozen plasma and/or platelets in conjunction with red blood cells due to MOH. We hypothesize that an early administration of plasma and platelets leads to fewer maternal mortalities and severe maternal morbidities than administration later on in treatment. TeMpOH-2 sets out to identify coagulation parameters predictive of progressing from mild postpartum hemorrhage into major obstetric hemorrhage.

TeMpOH-1

Rationale 

Major obstetric hemorrhage is the most important cause of severe maternal morbidity. Observational studies on massive hemorrhage associated with trauma and surgery have shown an apparent survival advantage with the administration of high cumulative ratios plasma and platelets to red blood cells. However, these results may have been confounded due to reverse causation and do not take time-varying treatment and time-dependent confounding into account. Furthermore, some authors recently proposed that not the ratios between the transfused blood components determine the outcome, but rather the timing of transfusion of plasma and platelets.  

Objective 

To determine the effect of early administration of plasma and platelets alongside RBCs on the clinical course of women with obstetric hemorrhage compared to administration at a later stage in treatment.

Study design 

Nationwide, retrospective cohort study. 

Study population

Women that, during pregnancy, delivery or puerperium, received transfusions of FFP and/or platelets alongside RBCs because of obstetric hemorrhage from 1 January 2011 until 1 January 2013 in the Netherlands. Obstetric hemorrhage requiring at least four units of packed red blood cells will be considered major obstetric hemorrhage.

Main study endpoints

Maternal mortality and severe maternal morbidity

Methods

Women that received FFP and/or platelets alongside RBCs due to obstetric hemorrhage will be identified by cross-referencing data from departments of blood transfusion services with data from local birth registers. Data on characteristics of and treatment of selected women will be collected by performing a chart review of patients. The effect of timing of transfusion of FFP and/or platelets in conjunction with RBC transfusion on maternal mortality and severe maternal morbidity will be determined by using an inverse probability weighted Cox proportional hazard model. 

TeMpOH-2

Rationale

In the management of severe postpartum hemorrhage (PPH), large volumes of infusions and transfusions of blood components are administered. In order to determine the optimal transfusion strategy during severe PPH, hemostasis parameters predictive of major obstetric hemorrhage, allogeneic blood use, maternal mortality and severe maternal morbidity need to be established. Therefore, the associations between haemostatic changes during postpartum hemorrhage and relevant clinical outcomes should be elucidated.

Objective

To examine the association between hemostasis parameters measured during ongoing blood loss and clinical outcomes in women suffering from postpartum hemorrhage, and compare them with those in women progressing into major obstetric hemorrhage. 

Study design

Multicenter prospective cohort study

Study population

Women experiencing postpartum hemorrhage. Postpartum hemorrhage will be defined as blood loss exceeding 1000 milliliters following delivery, and major obstetric hemorrhage as the need for transfusion of at least four units of red blood cells. 

Main study endpoints and parameters

Maternal mortality, severe maternal morbidity and the timing, amounts and type of allogeneic blood use. Data on the collected parameters include hemoglobin, hematocrit, platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen and ROTEM® profile.

Methods

Blood samples will prospectively be collected in consecutive women with blood losses of at least 1000 ml following delivery. Results of “conventional” hemostasis parameters and point-of-care coagulation tests of women with major obstetric hemorrhage will be compared to results of women with less severe postpartum hemorrhages. The strength of the associations between hemostasis parameters and maternal mortality, severe maternal morbidity and use of (allogeneic) blood components, and their independent predictive values will be compared using multivariate regression models and area under the receiver operating curves (ROC) of the predicted value of these models.