Obstetric hemorrhage: previa, accreta, atony
Stem
A 35-year-old G4P3, 78 kg, has a vaginal delivery of twins after a 20-hour oxytocin-augmented labor and chorioamnionitis, with a working labor epidural. Twenty minutes later the uterus is boggy and quantified blood loss is 1400 mL and rising. Blood pressure is 96/54, heart rate 124. She has mild asthma and her pressures were normal throughout labor.
Question
How do you manage this hemorrhage?
Ideal answer
HeadlinePostpartum hemorrhage from atony. I call for help, activate the massive transfusion protocol early, and run a staged protocol with the obstetric team, quantifying loss, not estimating it.
- Two large-bore IVs, arterial line; CBC, fibrinogen, viscoelastic testing, because the loss is ongoing.
- Uterotonics in sequence, naming each contraindication: oxytocin; methylergonovine, because she is not hypertensive; no carboprost, because she is asthmatic, so misoprostol.
- Tranexamic acid 1 g now, because she is within three hours of birth.1
- Near 1:1:1, fibrinogen above 200 mg/dL, because below 200 predicts progression to severe hemorrhage;2 warm, ionized calcium normal.
- Still bleeding: balloon tamponade, compression sutures, IR, hysterectomy, I prepare her and the team, and decide when the neuraxial block stops being the safe anesthetic.
Watch for: mental status, pressure, lactate and urine output, my markers of whether we are winning.
Breaking down the answer
- Fibrinogen is the early marker — obstetric coagulopathy is often fibrinogen-driven, especially with abruption and amniotic fluid embolism; cryoprecipitate or fibrinogen concentrate guided by viscoelastic testing, not a waited-for lab value.
- Uterotonic doses — oxytocin infusion; methylergonovine 0.2 mg IM only if normotensive, as it causes severe vasoconstriction and hypertension; carboprost 250 mcg IM avoided in asthma; misoprostol 600–1000 mcg an adjunct.3 Stating each contraindication with each drug shows application of knowledge.
- Convert to general early when unstable — a sympathectomized patient losing blood compensates poorly and cannot protect an obtunded airway; ketamine or etomidate at a reduced dose, not propofol at full dose.
- Planned accreta: a vascular case — maternal-fetal medicine, pelvic surgeons, urology, interventional radiology, obstetric anesthesia, critical care; a level III or higher center at about 34 0/7–35 6/7 weeks with massive transfusion capability;4 crossmatched blood in room, arterial line, large-bore access.
- Accreta: neuraxial or general — in a 47-patient multicentre series of planned-REBOA cases, 85% started neuraxial and 52.5% of those converted, mostly for pain or surgeon request.5 Changes if: extensive invasion or a long hysterectomy likely, I plan general.
- Balloons are a debate — prophylactic iliac balloons: a small randomized trial showed no benefit, arterial damage can occur, routine use not recommended.4 Infrarenal aortic occlusion: observational data: less blood loss (1231 vs 2253 mL) and hysterectomy (7.8% vs 25.8%), with limb arterial thrombosis.6
- Cell salvage is acceptable — ACOG/SMFM list it as an option in accreta,4 and amniotic fluid contamination concerns have not been borne out; leukocyte depletion filter, and anti-D if she is Rh-negative.
Follow-up question
Bleeding continues despite uterotonics and balloon tamponade, and she goes to the operating room for laparotomy under her epidural. Blood loss passes 3 L, the pressure is 70/40, and she becomes confused. What do you do now?
Follow-up answer
HeadlineHemorrhagic shock with a failing airway; I tell the room and secure the airway.
I convert to general anesthesia by rapid sequence with a small dose of ketamine and rocuronium, call for more hands, and run blood through a rapid infuser. Products by ratio while a viscoelastic test and fibrinogen run; calcium chloride for ionized calcium below 1.1 mmol/L, because citrate-induced hypocalcemia and hypothermia worsen coagulopathy and contractility; TXA confirmed. I tell the obstetricians that if bleeding continues, hysterectomy now is better than more blood. Acid-base, potassium and temperature every 15–30 minutes.
Pitfalls that cost points
- Estimating blood loss visually and under-calling it; young women compensate until they collapse.
- Giving crystalloid in large volume while waiting for blood.
- Giving methylergonovine to a pre-eclamptic patient or carboprost to an asthmatic.
- Listing uterotonics without stating who does what in the room; hemorrhage is the leading preventable cause of maternal death, more often team failure than technical.
Rapid-fire
Q: Why is fibrinogen higher at baseline in pregnancy? A: Pregnancy is procoagulant; normal fibrinogen is 400–600 mg/dL, so a "normal" lab value of 200 is already a large drop.
Q: When does TXA lose its benefit? A: Starting it more than three hours after birth confers no benefit; the WOMAN trial showed reduced bleeding deaths when given early.1
Q: What risk factor matters most for accreta? A: Placenta previa with prior cesarean; with previa the risk is about 3%, 11%, 40%, 61% and 67% after one through five or more cesareans.4
Q: What if accreta is found unexpectedly at cesarean? A: If nothing mandates immediate delivery, pause; alert anesthesia, consider general, add access, blood and cell salvage.4
Q: Why is atony the most common cause? A: The uterus stops bleeding by contracting around spiral arteries; anything that impairs contraction (overdistension, prolonged labor, chorioamnionitis, volatile agents) leaves them open.
Numbers to know
| Item | Value |
|---|---|
| Postpartum hemorrhage | ≥1000 mL cumulative loss or loss with hypovolemia, within 24 h3 |
| Tranexamic acid | 1 g IV at 1 mL/min within 3 h; second 1 g if bleeding continues at 30 min or recurs within 24 h1 |
| Methylergonovine | 0.2 mg IM every 2–4 h; avoid in hypertension or pre-eclampsia3 |
| Carboprost | 250 mcg IM every 15–90 min, max 2 mg (8 doses); caution in asthma7 |
| Fibrinogen target | >200 mg/dL |
| Uterine blood flow at term | ~700 mL/min |
Links
- Massive hemorrhage and transfusion, Uterotonics and tocolytics, dic, Amniotic fluid embolism, Perioperative hypothermia and coagulopathy, The patient who refuses blood
- ACOG Practice Bulletin on postpartum hemorrhage; ACOG/SMFM obstetric care consensus on placenta accreta spectrum
Sources
- 1.Joint statement of recommendation for the use of tranexamic acid for the treatment of postpartum haemorrhage · FIGO / ICM · figo.org
- 2.Association between fibrinogen levels and severity of postpartum haemorrhage · Colombian Journal of Anesthesiology · elsevier.es
- 3.Postpartum Hemorrhage: Medications to Treat Uterine Atony · The ObG Project, 2022 · obgproject.comSummary drawing on ACOG Practice Bulletin 183.
- 4.Placenta Accreta Spectrum (Obstetric Care Consensus No. 7) · ACOG/SMFM, 2018 · assets.noviams.com
- 5.Anaesthetic strategies for managing placenta accreta spectrum with REBOA: insights from an international multicentre retrospective study · European Journal of Anaesthesiology (Azem K et al.), 2025 · cris.tau.ac.ilEur J Anaesthesiol 2025;42(9):791-9. 47 PAS caesareans with REBOA; 85.1% neuraxial first, 52.5% of those converted (pain 52.4%, surgeon request 42.9%).
- 6.Assessment of Abdominal Aorta Balloon Occlusion Efficiency and Safety in Patients with Placenta Accreta Spectrum Disorder: A Systematic Review and Meta-Analysis · Journal of Clinical Medicine (Abdukassimova, Aimagambetova, Terzic et al.), 2026 · europepmc.orgFull text via Europe PMC (PMC13163405); 24 observational studies, mostly infrarenal; blood loss 1231 vs 2253 mL, hysterectomy 7.8% vs 25.8%.
- 7.Hemabate (carboprost tromethamine) prescribing information · Pfizer (FDA labeling) · pfizermedical.com
Facts on this page were checked against these sources on Oct 14, 2026. Guidelines change; confirm doses against current institutional protocols.