Tranexamic Acid and Thromboelastography During Cesarean Delivery
Condition: Postpartum Hemorrhage
MeSH terms: Postpartum Hemorrhage; Hemorrhage
Intervention: Tranexamic Acid; Placebo; Normal Saline
Intervention description: 1 gram IV over 10 minutes; 0.9% Normal Saline
Intervention MeSH terms: Tranexamic Acid
Phase: Phase 2
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 60.0
Sex: Female
Minimum age: 18 Years
Maximum age: 50 Years
Healthy volunteers: No
Keywords: postpartum hemorrhage; estimated blood loss; coagulation; thromboelastography; tranexamic acid

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).
    

Eligibility criteria:

        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