Prediction of Platelet Function Using Viscoelastic Test (ROTEM® Sigma) in Obstetric Anesthesia.

Official title

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

Overview

This prospective observational, non-interventional, single-center study aims to evaluate whether the viscoelastic parameter PLTEM, derived from ROTEM® sigma testing (EXTEM-A5 minus FIBTEM-A5), can accurately estimate platelet count in obstetric patients with thrombocytopenia and/or severe postpartum hemorrhage. The study will include pregnant women older than 18 years managed during labor and delivery at the Hospital General Universitario Gregorio Marañón, Madrid (Spain). The primary objective is to validate the clinical usefulness of PLTEM as a rapid point-of-care tool to support clinical decision-making regarding neuraxial anesthesia and transfusion management in obstetric emergencies.

Detailed description

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.

Clinical and laboratory data will be collected as part of routine care during the intrapartum and immediate postpartum periods. Variables recorded will include demographic characteristics, conventional laboratory parameters, ROTEM® variables, neuraxial anesthesia procedures, quantification of hemorrhage, transfusion requirements, need for reintervention, and maternal complications.

The primary objective is to validate the clinical usefulness of PLTEM in the obstetric setting and assess its correlation with conventional platelet count measurements. Secondary objectives include evaluation of additional ROTEM® parameters associated with coagulation abnormalities, assessment of transfusion requirements and hemorrhagic outcomes, and exploration of the relationship between thrombocytopenia, fibrinogen levels, and other factors contributing to obstetric coagulopathy.

The estimated minimum sample size is 85 patients, adjusted for an anticipated 20% loss rate. Statistical analyses will be performed using SPSS version 29.0. The study period will extend from protocol approval until completion of recruitment, with an anticipated completion date of December 2026.

Interventions

• Other No Intervention: Observational Cohort
  No intervention: observational study

Primary outcome measures

• To evaluate the correlation between PLTEM value and platelet count on hemogram [Time frame: At admission to the labour ward in case of thrombocytopenia inferior to 120,000 /mm^3 platelets in the third trimester of pregnancy, or at diagnosis of a severe Post-Partum Hemorrhage > 1,500 mL, until 24 hours after delivery or cesarean delivery.]

Secondary outcome measures (2)

• Relationship between ROTEM® parameters, thrombocytopenia, and fibrinogen levels [Time frame: From admission to the labour ward or from diagnosis of severe postpartum hemorrhage (>1,500 mL), through 24 hours postpartum.]
• PLTEM threshold for safe neuraxial anesthesia in thrombocytopenic obstetric patients [Time frame: At admission to the labour ward.]

Eligibility criteria

Inclusion criteria

• Parturients with a suspicion or confirmed thrombocytopenia before delivery (platelet count < 120x10\^9/L),
• Parturients with severe postpartum haemorrhage (blood loss >1500 mL) with a suspicion of thrombocytopenia.

Exclusion criteria

• parturient age under 18 years;
• refusal to participate

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Cohort

Study locations

Spain · 1 center

• Hospital General Universitario Gregorio Marañón — Madrid

Publications

• Bell SF, Kitchen T, John M, Scarr C, Kelly K, Bailey C, James K, Watkins A, Macgillivray E, Edey T, Greaves K, Volikas I, Tozer J, Sengupta N, Francis C, Collis R, Collins P. Designing and implementing an all Wales postpartum haemorrhage quality improvement project: OBS Cymru (the Obstetric Bleeding Strategy for Wales). BMJ Open Qual. 2020 Apr;9(2):e000854. doi: 10.1136/bmjoq-2019-000854. PMID 32273281
• Scala E, Coutaz C, Gomez F, Alberio L, Marcucci C. Comparison of ROTEM Sigma to Standard Laboratory Tests and Development of an Algorithm for the Management of Coagulopathic Bleeding in a Tertiary Center. J Cardiothorac Vasc Anesth. 2020 Mar;34(3):640-649. doi: 10.1053/j.jvca.2019.10.016. Epub 2019 Oct 11. PMID 31699598
• Ji SM, Kim SH, Nam JS, Yun HJ, Choi JH, Lee EH, Choi IC. Predictive value of rotational thromboelastometry during cardiopulmonary bypass for thrombocytopenia and hypofibrinogenemia after weaning of cardiopulmonary bypass. Korean J Anesthesiol. 2015 Jun;68(3):241-8. doi: 10.4097/kjae.2015.68.3.241. Epub 2015 May 28. PMID 26045926
• Lang T, Johanning K, Metzler H, Piepenbrock S, Solomon C, Rahe-Meyer N, Tanaka KA. The effects of fibrinogen levels on thromboelastometric variables in the presence of thrombocytopenia. Anesth Analg. 2009 Mar;108(3):751-8. doi: 10.1213/ane.0b013e3181966675. PMID 19224779
• Leyra F, Jofre C, Pena N, Olmos E, Del Campo JM, Aranzubia M, Moreno I. Prediction of platelet counts with ROTEM-sigma in cardiac surgery. Minerva Anestesiol. 2022 Jul-Aug;88(7-8):573-579. doi: 10.23736/S0375-9393.22.15912-2. Epub 2022 Apr 5. PMID 35381835
• Solomon C, Collis RE, Collins PW. Haemostatic monitoring during postpartum haemorrhage and implications for management. Br J Anaesth. 2012 Dec;109(6):851-63. doi: 10.1093/bja/aes361. Epub 2012 Oct 16. PMID 23075633
• Bell SF, Collis RE, Bailey C, James K, John M, Kelly K, Kitchen T, Scarr C, Macgillivray E, Collins PW. The incidence, aetiology, and coagulation management of massive postpartum haemorrhage: a two-year national prospective cohort study. Int J Obstet Anesth. 2021 Aug;47:102983. doi: 10.1016/j.ijoa.2021.102983. Epub 2021 Mar 26. PMID 33994274
• Duque González P. Tromboelastometría. Rev Elect AnestesiaR. 2017;9(7):3. Disponible en: http://anestesiar.org/2016/tromboelastometria/

Identifiers

NCT: NCT07616349 · ROTEMPLAQ

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗