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

May 29, 2026 updated by: Nicolas Brogly

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

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.

Study Overview

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.

Study Type

Observational

Enrollment (Estimated)

85

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

      • Madrid, Spain, 28007
        • Recruiting
        • Hospital General Universitario Gregorio Marañon
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Probability Sample

Study Population

Cohort of consecutive consenting patients with suspicion and/or confirmed thrombocytopenia admitted in the labor ward, the obstetric operating room or the obstetric post anaesthetic care unit for delivery in a tertiary university hospital in Madrid-Spain for a period of 1 year.

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Obstetric Patients with confirmed or suspicion of thrombocytopenia

The study will include all the consecutive consenting parturients admitted to our maternal unit in the inclusion period with the following inclusion and exclusion 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

No intervention: observational study

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
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.
A blood sample will be extracted in patients at risk or with confirmed thrombcytopenia. A simultaneous platelet count (standard biological test) and ROTEM sigma viscoelastic test will be performed. The correlation between PLTEM5 (EXTEM A5 - FIBTEM A5), PLTEM10 (EXTEM A10 - FIBTEM A10) and platelet count will be determined.
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

Outcome Measure
Measure Description
Time Frame
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.
To assess the correlation between ROTEM® sigma-derived parameters (FIBTEM, EXTEM, and INTEM) and standard coagulation assays, including: Clauss fibrinogen, prothrombin time (PT), and activated partial thromboplastin time (aPTT), in obstetric patients with thrombocytopenia and/or postpartum hemorrhage ≥1,500 mL, with the aim of characterizing the coagulopathy profile in these scenarios, with particular attention to hypofibrinogenemia and platelet function.
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.
To assess whether a specific PLTEM threshold can be determined with ROTEM® sigma to identify obstetric patients above the established safety platelet count threshold for neuroaxial anesthesia (≥ 70 × 10⁹/L) in a clinically useful timeframe compared to conventional laboratory test.
At admission to the labour ward.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 1, 2026

Primary Completion (Estimated)

May 1, 2027

Study Completion (Estimated)

May 1, 2027

Study Registration Dates

First Submitted

April 28, 2026

First Submitted That Met QC Criteria

May 29, 2026

First Posted (Actual)

June 1, 2026

Study Record Updates

Last Update Posted (Actual)

June 1, 2026

Last Update Submitted That Met QC Criteria

May 29, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

This was not considered in the design of the research.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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