Tranexamic Acid and Thromboelastography During Cesarean Delivery

Phase 2

Terminated

Conditions: Postpartum Hemorrhage

Interventions: Drug: Placebo; Normal Saline
Drug: Tranexamic Acid

Registration Number: NCT02026297

Lead Sponsor: Brigham and Women's Hospital

Brief Summary: The aim of this study is to characterize the coagulation changes, using thromboelastography (TEG), after prophylactic tranexamic administration during cesarean delivery. Specifically, TEG values will be compared in patients who receive prophylactic tranexamic acid or placebo before surgery, during elective cesarean delivery, and 2 hours postpartum.

Postpartum hemorrhage (PPH) is increasing in incidence in the United States, renewing interest in multimodal approaches to blood conservation during cesarean delivery. Pharmacologic therapy with the antifibrinolytic agent, tranexamic acid (TA), has been shown to reduce estimated blood loss (EBL) during cesarean delivery, but its effect on global coagulation as assessed by TEG, and how this correlates with lowering blood loss, has not been elucidated.

This study will be conducted as a randomized, double-blind, controlled trial with two study arms: control (60 patients); and treatment (60 patients).

Subjects will be pre-medicated with routine pre-cesarean delivery medications including oral sodium citrate 30 mL and intravenous (IV) metoclopramide 10 mg. A peripheral IV and noninvasive hemoglobin monitor will be placed, and baseline labs sent: type and screen, serum hemoglobin, platelet count, fibrinogen, activated partial thromboplastin time (aPTT), prothrombin time (PT), and baseline TEG values (r time, k time, alpha angle, and maximum amplitude). Patients will have blood pressure, heart rate, and pulse oximetry measured throughout surgery as per standard of care. Patients will all receive IV lactated Ringers' (LR) solution prior to surgery and throughout surgery, with volume recorded and a goal of less than 2 L unless more IV fluid is clinically indicated. All patients will have a spinal anesthetic as per standard of care, with hyperbaric bupivacaine 12 mg, fentanyl 10 μg, and hydromorphone 100 μg. If the anesthetic plan is altered (combined spinal-epidural, general anesthesia conversion, general anesthesia planned), indications and medication doses used will be noted for analysis.

Immediately following induction of anesthesia and prior to skin incision, infusion of study solution will be initiated.

Study solutions will consist of:

1. Control group: 100 mL 0.9% normal saline (NS).

2. Treatment group: 100 mL 0.9% NS containing 1g tranexamic acid (TA). Study solution will be infused via an infusion pump over 10 minutes. Blood loss will be measured by visual estimate and weight of surgical sponges. Noninvasive hemoglobin will be measured throughout the study. All routine care lab values will be noted. At minimum, one lab panel will be sent one hour after study solution initiation (hemoglobin, fibrinogen, platelet count, aPTT, PT, and TEG).

Detailed Description: Not available

Recruitment & Eligibility

Status: TERMINATED

Sex: Female

Target Recruitment: 60

Inclusion Criteria

American Society of Anesthesiologists (ASA) class I or II
aged 18-50 years
singleton vertex pregnancy
scheduled elective cesarean delivery (with or without prior labor) with a planned pfannenstiel incision

Exclusion Criteria

allergy to tranexamic acid
history of inherited or acquired thrombophilia
history of deep vein thrombosis or pulmonary embolism, or use of anticoagulant medication.
preeclampsia, hemolysis, elevated liver enzymes, low platelet syndrome
seizure disorder

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Control, low risk PPH	Placebo; Normal Saline	Patients at lower risk for postpartum hemorrhage during cesarean delivery, to receive standard of care NOT including tranexamic acid.
Treated, low risk PPH	Tranexamic Acid	Patients at lower risk for postpartum hemorrhage during cesarean delivery, to receive standard of care AND tranexamic acid.

Primary Outcome Measures

Name	Time	Method
Intraoperative Blood Loss	during surgery in the operating room	Blood loss will be measured using the following methods: * visual estimate of blood in the suction canister * weight of surgical sponges * postoperative hemoglobin values
TEG Value- Thromboelastography R-time, Control and Treated Groups	one hour after initiation of study infusion	Blood samples will be collected for evaluation one our after initiation of the study infusion. Whole blood samples are tested in a point-of-care thromboelastography machine and R time, or time to initiation of clot formation, is measured in minutes.
Delayed Complications at the 6-Week Postpartum Visit With the Obstetrician.	6 weeks postpartum	The electronic patient record from each patients' 6-week postpartum visit will be reviewed for the following: * delayed bleeding complications, defined as obstetric bleeding requiring surgical intervention, blood transfusion, or both. * thrombotic complications including: venous thrombus seen on ultrasound, thromboembolic event