How to minimize blood loss during a cesarean section with uterine (uterine) myoma (fibroids)?

Minimizing Blood Loss During Cesarean Section with Uterine Myomas

For cesarean delivery in women with uterine fibroids, use blunt expansion of the transverse uterine hysterotomy, administer prophylactic tranexamic acid 1g IV prior to skin incision, optimize oxytocin dosing (5 IU IV bolus followed by infusion), and have cell salvage equipment available for abnormal bleeding. 1

Surgical Technique Modifications

Uterine Incision Management

• Perform blunt expansion of the transverse uterine hysterotomy rather than sharp extension, as this technique reduces surgical blood loss during cesarean delivery 1
• Close the hysterotomy in two layers, which may be associated with lower rates of uterine rupture in subsequent pregnancies, though evidence is of low quality 1
• Avoid peritoneal closure, as it does not improve outcomes and increases operative time without reducing blood loss 1

Subcutaneous Tissue Management

• Reapproximate subcutaneous tissue if ≥2 cm thick, as this reduces wound complications 1
• Use subcuticular suture for skin closure rather than staples, which reduces wound separation and improves patient satisfaction 1

Pharmacological Blood Loss Prevention

Tranexamic Acid Administration

• Administer tranexamic acid 1g IV over 10 minutes prior to skin incision and at the end of surgery for major non-cardiac surgery 1
• This antifibrinolytic agent is particularly important given the increased bleeding risk associated with myomas 1
• If bleeding continues postoperatively, a second 1g dose can be given if bleeding persists after 30 minutes or restarts within 24 hours 1

Oxytocin Optimization

• Use 5 IU oxytocin IV bolus after delivery of the neonate, followed by 20-25 IU in 500 mL lactated Ringer's solution infused over 3 hours 2, 3
• The 5 IU dose provides equivalent uterine tone and blood loss control compared to 10 IU, with significantly better hemodynamic stability and fewer side effects 3
• Avoid large bolus doses (10 IU), as they cause greater heart rate variation, hypotension incidence, and digestive side effects without improving uterine contraction 4, 3
• The ED90 for effective uterine contraction in non-laboring women is only 0.35 IU, suggesting current practice uses excessive doses 5

Alternative Uterotonic Agents

• Consider rectal misoprostol 800 mcg at the time of peritoneal incision as an alternative to oxytocin infusion, which has been shown to reduce intraoperative blood loss (503 vs 592 mL) and postoperative blood loss (74 vs 114 mL) 6
• The main side effect is increased shivering (8.3% vs 1.1%), but this may be acceptable given the superior blood loss reduction 6

Perioperative Fluid Management

Euvolemia Maintenance

• Maintain perioperative euvolemia to optimize uterine perfusion and oxygen delivery, which is critical for adequate myometrial contraction 1
• Avoid fluid overload, which increases cardiovascular work, pulmonary edema risk, and can cause newborn weight loss in the first 3 days 1
• Adequate uterine perfusion delivers nutrients and eliminates waste products from the myometrium, supporting effective contraction 1

Blood Conservation Strategies

Cell Salvage

• Have cell salvage equipment immediately available, as it is recommended if abnormal bleeding occurs during cesarean section 1
• Use a leucocyte filter for autotransfusion of processed blood 1
• This is particularly important in cases with myomas where bleeding risk is elevated 1

Blood Loss Measurement

• Use volumetric and gravimetric techniques to measure blood loss cumulatively rather than relying on visual estimation, which is notoriously inaccurate 1
• Implement early recognition protocols with clear escalation plans for obstetric intervention and multi-professional team involvement 1

Coagulation Monitoring and Management

Early Fibrinogen Assessment

• Monitor fibrinogen levels if bleeding exceeds 1000 mL, as hypofibrinogenaemia (fibrinogen <2 g/L) occurs in 5% of hemorrhages at this threshold and 17% at 2500 mL 1
• Fibrinogen <3 g/L, especially <2 g/L, with ongoing bleeding is associated with progression to massive obstetric bleeding (>2500 mL) 1
• Early identification and treatment of hypofibrinogenaemia can reduce progression from major to massive postpartum hemorrhage 1

Coagulation Factor Replacement

• Administer cryoprecipitate or fibrinogen concentrate early if fibrinogen <2 g/L with ongoing bleeding, potentially before red blood cell transfusion 1
• Use fresh frozen plasma (FFP) if PT or APTT is prolonged above normal non-pregnant range, as this indicates factor depletion 1
• For traumatic or atonic bleeding without known coagulation results, withhold FFP until four units of RBC have been given, unless early coagulopathy is diagnosed on coagulation screening 1

Preoperative Optimization

Antibiotic Prophylaxis

• Administer weight-based cefazolin IV within 60 minutes before skin incision 7
• Add azithromycin 500mg IV for patients in labor or with ruptured membranes 7

Anesthetic Considerations

• Use regional anesthesia (spinal or epidural) rather than general anesthesia, as it reduces the stress response and avoids risks of general anesthesia 7
• Regional anesthesia also facilitates better hemodynamic control during oxytocin administration 4

Common Pitfalls to Avoid

• Avoid administering oxytocin 10 IU as a rapid bolus, as this causes significant hemodynamic instability without improving uterine tone compared to lower doses 4, 3
• Do not rely on visual estimation of blood loss, as this consistently underestimates actual blood loss and delays appropriate intervention 1
• Avoid delaying tranexamic acid administration, as efficacy decreases significantly if given more than 3 hours after bleeding onset 1
• Do not wait for coagulation results before implementing active management of the third stage of labor with uterotonics, as sustained myometrial contraction is the primary mechanism to stem placental bed bleeding 1
• Avoid sharp extension of the uterine incision, as blunt expansion reduces blood loss 1