Chapter 3: Tranexamic Acid

BACKGROUND

Obstetric hemorrhage is the leading cause of maternal mortality worldwide. Despite active management during the third stage of labor, postpartum hemorrhage (PPH) remains a problem and is increasing in the United States, primarily due to the increasing incidence of atony.¹ Tranexamic acid (TXA) is a lysine analogue and works by binding to plasminogen, thereby inhibiting fibrinolysis. TXA has been used for years in the management and prevention of hemorrhage in the surgical setting, including cardiac, orthopedic, and trauma surgery.^2,3

Prior studies have established the safety and efficacy of using TXA in the treatment of PPH. More recently, a large, international, multicenter, randomized control trial (The WOMAN trial) demonstrated a significant reduction in PPH and death due to bleeding when TXA was used early in the treatment of PPH.⁴ Although there is less data, several studies have demonstrated its efficacy in preventing PPH in patients at both average or increased risk when given immediately after delivery in cesarean deliveries.^5-7 Conversely, large randomized studies have shown modest to no benefit of prophylactic TXA to prevent PPH in healthy parturients undergoing vaginal delivery compared to placebo.^8-10 Despite concerns for potentially increasing thromboembolic events, no study to date has indicated any increased risk in gravid patients receiving TXA. Given this data, our goals are outlined below.

GOALS

• To reduce the severity of PPH once a patient has been identified as having excessive bleeding (estimated blood loss >500 mL in vaginal delivery or >1000 mL in vaginal delivery or cesarean delivery).

• To reduce the incidence of PPH in patients at high-risk for hemorrhage due to known risk factors.

CLINICAL PRACTICE

• Therapeutic use: Consider use when patient has been identified as having a hemorrhage. Team agreement prior to administration.

• Prophylactic use: Consider prophylactic use in cesarean or vaginal delivery with patients at increased risk for hemorrhage (see criteria below), especially in circumstances where uterotonics may be contraindicated. Discuss possible use at briefing or at team meeting.

METHOD OF ADMINISTRATION

Dosage: 1 g given intravenously over 10 minutes. Possible methods of administration include 1 g diluted into 10 ml of normal saline or 1 g diluted into 100 ml of normal saline.

Timing: Administer when hemorrhage has been identified. In high-risk patients where prophylactic administration has been agreed upon, initiate immediately after delivery of baby in either vaginal or cesarean delivery. Consider redosing 1 g after 30 minutes of continuing hemorrhage. Consider infusion (5 mg/kg/h) if prolonged bleeding period is expected.

SIDE EFFECTS

Minor: nausea, vomiting, gastrointestinal upset, headaches, dizziness, hypotension, color blindness

Major: thromboembolic complications, e.g., pulmonary embolism (PE), deep vein thrombosis (DVT), myocardial infarction, seizure, anaphylaxis

Caution: mistakenly administration of TXA into epidural or subarachnoid space can ...