Prediction of Platelet Function Using Viscoelastic Test (ROTEM® Sigma) in Obstetric Anesthesia: an Prospective Observational Study

Obstetric hemorrhage remains the leading cause of maternal mortality worldwide. In Spain, recent studies estimate an incidence between 2% and 5%. The main causes include uterine atony, genital tract trauma, retained placental tissue, and coagulation disorders. Early recognition and management of coagulation abnormalities are essential to reduce maternal morbidity and mortality.

Viscoelastic testing using rotational thromboelastometry (ROTEM® sigma) provides dynamic real-time assessment of coagulation and has become increasingly integrated into obstetric hemorrhage management algorithms. Platelet function plays a major role in clot formation, and impairment of platelet quantity or function may influence transfusion strategies and the safety of neuraxial anesthesia techniques.

The PLTEM parameter (Platelet contribution to clot firmness) estimates platelet contribution to clot strength and is calculated as the difference between EXTEM-A5 and FIBTEM-A5. In other clinical settings, PLTEM-derived measurements have demonstrated the ability to estimate platelet count with good accuracy. However, evidence validating its utility in obstetric patients remains limited.

The hypothesis of this study is that PLTEM may provide a reliable and rapid estimation of platelet count in urgent obstetric settings, thereby optimizing clinical decision-making, facilitating safer neuraxial anesthesia management, and improving transfusion practices.

This is a prospective, observational, non-interventional, single-center study conducted at the Hospital General Universitario Gregorio Marañón, Madrid (Spain). The study population will include pregnant women older than 18 years attended during labor and delivery who present with thrombocytopenia of any etiology and/or develop postpartum hemorrhage greater than 1,500 mL. Patients who decline participation will be excluded.