CARDIAC ARREST IN PREGNANCY
OBSTETRIC CARDIOPULMONARY RESUSCITATION, PERIMORTEM CESAREAN SECTION, MATERNAL-FETAL PHYSIOLOGY AND UPDATED 2026 RECOMMENDATIONS
Scientific and emergency medicine review based on AHA, ILCOR, ERC, ACOG and international obstetric resuscitation literature
By DrRamonReyesMD ⚕️
EMS Solutions International
Updated 2026
INTRODUCTION
Cardiac arrest during pregnancy is one of the most complex and physiologically demanding emergencies in emergency medicine, critical care, obstetrics and trauma care.
Although relatively uncommon, maternal and fetal mortality remain extremely high.
The major challenge is that:
TWO PATIENTS ARE BEING RESUSCITATED SIMULTANEOUSLY
mother and fetus.
However:
fetal survival initially depends on:
EFFECTIVE MATERNAL RESUSCITATION.
Every intervention must prioritize:
- maternal cerebral perfusion,
- maternal oxygenation,
- maternal venous return,
- maternal cardiac output.
Because:
THE FETUS CANNOT SURVIVE IF MATERNAL PERFUSION IS LOST.
EPIDEMIOLOGY
Maternal cardiac arrest is estimated to occur in approximately:
1 per 12,000 to 30,000 pregnancies
depending on the healthcare system and case definition used.
In the United States:
approximately:
17.4 cases per 1,000 critical obstetric admissions
require advanced resuscitative interventions.
Maternal mortality remains significant.
The most common causes include:
- obstetric hemorrhage,
- amniotic fluid embolism,
- preeclampsia/eclampsia,
- pulmonary embolism,
- peripartum cardiomyopathy,
- sepsis,
- trauma,
- intoxications,
- anesthetic complications.
PHYSIOLOGICAL CHANGES OF PREGNANCY RELEVANT TO CPR
Advanced pregnancy profoundly alters:
- hemodynamics,
- ventilatory mechanics,
- oxygenation,
- shock response.
1. AORTOCAVAL COMPRESSION
After approximately:
20 weeks gestation
the gravid uterus compresses:
- the inferior vena cava,
- the abdominal aorta.
This reduces:
- venous return,
- preload,
- cardiac output.
In the supine position, cardiac output may decrease:
up to 30–40%.
Therefore:
THE PREGNANT PATIENT IN CARDIAC ARREST MUST NOT REMAIN COMPLETELY SUPINE WITHOUT UTERINE DISPLACEMENT.
2. INCREASED OXYGEN CONSUMPTION
Pregnancy increases:
- metabolic demand,
- oxygen consumption,
- minute ventilation.
At the same time:
functional residual lung capacity decreases.
Result:
HYPOXIA DEVELOPS MUCH MORE RAPIDLY.
3. INCREASED ASPIRATION RISK
There is:
- relaxation of the lower esophageal sphincter,
- increased intraabdominal pressure,
- delayed gastric emptying.
Every pregnant patient must be considered:
A FULL STOMACH.
4. MORE DIFFICULT AIRWAY
Mucosal edema and anatomical changes increase:
- intubation difficulty,
- airway bleeding,
- hypoxia during prolonged attempts.
MODERN PRINCIPLES OF CPR IN PREGNANCY 2026
Current recommendations from:
- AHA,
- ILCOR,
- ERC,
- ACOG,
- SMFM,
maintain the same fundamental principle:
HIGH-QUALITY CPR REMAINS THE CENTRAL PILLAR.
However, important pregnancy-specific modifications are required.
ABSOLUTE PRIORITIES
- HIGH-QUALITY CPR
- EARLY OXYGENATION AND AIRWAY MANAGEMENT
- LEFT UTERINE DISPLACEMENT
- IMMEDIATE DEFIBRILLATION
- IDENTIFICATION OF REVERSIBLE CAUSES
- EARLY PERIMORTEM CESAREAN SECTION IF NO ROSC
HIGH-QUALITY CPR
Chest compressions should be performed exactly as in adults:
- 100–120/min,
- depth 5–6 cm,
- minimal interruptions,
- complete chest recoil.
LEFT UTERINE DISPLACEMENT
This point is CRITICAL.
The uterus must be manually displaced to the left:
FROM THE VERY BEGINNING OF CPR.
Goal:
relieve aortocaval compression.
This may be achieved:
- manually,
- or with 15–30 degree left lateral tilt.
However:
excessive tilt worsens compression quality.
Therefore:
modern guidelines favor:
MANUAL LEFT UTERINE DISPLACEMENT
while maintaining a relatively supine position.
AIRWAY MANAGEMENT AND OXYGENATION
AHA 2020–2025 and updated 2026 recommendations emphasize:
OXYGENATION IS AN ABSOLUTE PRIORITY.
Because of:
- increased oxygen consumption,
- decreased pulmonary reserve,
- immediate fetal hypoxia risk.
RECOMMENDATIONS
- 100% oxygen.
- Effective bag-valve-mask ventilation with excellent seal.
- Early intubation by experienced operator.
- Avoid repeated failed attempts.
- Slightly smaller ET tube due to airway edema.
- Continuous capnography whenever available.
DEFIBRILLATION
Defibrillation:
IS NOT CONTRAINDICATED IN PREGNANCY.
It must be performed:
without delay.
There is no evidence of clinically significant fetal harm from maternal defibrillation.
The true danger to the fetus is:
DELAYED RESTORATION OF MATERNAL CIRCULATION.
ACLS MEDICATIONS
ACLS drug dosing remains essentially unchanged:
- epinephrine 1 mg IV every 3–5 min,
- amiodarone,
- lidocaine,
- magnesium when indicated.
Drug doses should not be reduced because of pregnancy.
Hs AND Ts IN PREGNANCY
Always consider:
Hs
- Hypoxia
- Hypovolemia
- Hydrogen ion excess/acidosis
- Hypo/hyperkalemia
- Hypothermia
Ts
- Tamponade
- Pulmonary thrombosis
- Coronary thrombosis
- Tension pneumothorax
- Toxins
Additional obstetric causes include:
- massive hemorrhage,
- amniotic fluid embolism,
- eclampsia,
- HELLP syndrome,
- placental abruption,
- uterine rupture.
PERIMORTEM CESAREAN SECTION
Also known as:
RESUSCITATIVE HYSTEROTOMY.
This is probably:
THE MOST IMPORTANT CONCEPT IN OBSTETRIC CARDIAC ARREST.
THE 4–5 MINUTE RULE
If there is NO ROSC by:
4 minutes
providers should initiate:
PERIMORTEM CESAREAN SECTION
with the goal of fetal delivery before:
5 minutes.
THE TRUE OBJECTIVE
Many people mistakenly believe the primary objective is fetal rescue.
It is not.
The immediate primary objective is:
IMPROVEMENT OF MATERNAL RESUSCITATION.
Emptying the uterus:
- improves venous return,
- increases cardiac output,
- improves ventilation,
- improves chest compression effectiveness.
Maternal cardiac output may improve:
30–80%.
WHO SHOULD PERFORM IT?
Critical modern principle:
DO NOT WAIT FOR AN OBSTETRICIAN IF ONE IS NOT IMMEDIATELY AVAILABLE.
Any properly trained physician should initiate the procedure.
Because:
THE ENEMY IS TIME.
GENERAL TECHNIQUE
- Rapid vertical midline infraumbilical incision.
- Immediate uterine opening.
- Rapid fetal extraction.
- Continuous CPR throughout the procedure.
Transport should not delay life-saving intervention.
FETAL SURVIVAL
Best neonatal outcomes occur when delivery occurs:
≤5 minutes.
Reported neonatal survival:
approximately 69%
when delivery occurs before 5 minutes.
After that:
survival decreases dramatically.
POST-ROSC MANAGEMENT
If maternal circulation returns:
- optimize ventilation,
- avoid hypotension,
- avoid hypoxemia,
- invasive monitoring when available,
- ultrasound evaluation,
- obstetric consultation,
- ICU management.
TARGETED TEMPERATURE MANAGEMENT
AHA continues to state that:
pregnant post-cardiac arrest patients may receive:
TARGETED TEMPERATURE MANAGEMENT
when clinically indicated.
However, this requires:
- continuous fetal monitoring,
- obstetric consultation,
- neonatal consultation.
FETAL MONITORING DURING ACTIVE CPR
Important:
AHA states:
FETAL MONITORING MUST NOT DELAY MATERNAL RESUSCITATION.
Fetal monitoring during active maternal arrest:
- distracts providers,
- delays interventions,
- worsens maternal resuscitation quality.
First priority:
SAVE THE MOTHER.
TRAUMA AND PREGNANCY
In trauma:
maternal resuscitation remains the priority.
Providers must suspect:
- occult hemorrhage,
- placental abruption,
- uterine rupture,
- thoracic trauma,
- hypovolemic shock.
Pregnant trauma patients require:
- uterine displacement,
- aggressive hemorrhage control,
- early oxygenation,
- rapid transport.
AIRWAY OBSTRUCTION
Important classical point:
In advanced pregnancy:
ABDOMINAL HEIMLICH MANEUVERS SHOULD BE AVOIDED.
Instead:
CHEST THRUSTS ARE RECOMMENDED.
SIMULATION AND TRAINING
Obstetric emergencies require regular simulation training.
Training should include:
- obstetric CPR,
- uterine displacement,
- difficult airway management,
- massive hemorrhage,
- perimortem cesarean section,
- multidisciplinary teamwork.
Because:
MOST FAILURES OCCUR DUE TO DELAY AND DISORGANIZATION.
CENTRAL MESSAGE
In obstetric cardiac arrest:
EVERY SECOND MATTERS.
Modern pillars include:
- excellent CPR,
- early oxygenation,
- uterine displacement,
- immediate defibrillation,
- identification of reversible causes,
- early perimortem cesarean section.
Perimortem cesarean section:
is not merely a fetal procedure.
It is:
A MATERNAL RESUSCITATIVE INTERVENTION.
KEY PHRASE
“Two lives depend on one resuscitation.”
UPDATED REFERENCES 2026
AMERICAN HEART ASSOCIATION
CARDIAC ARREST IN PREGNANCY
https://www.ahajournals.org/doi/10.1161/CIR.0000000000000905
DOI
10.1161/CIR.0000000000000905
2020 AMERICAN HEART ASSOCIATION GUIDELINES FOR CPR AND ECC
CIRCULATION
https://www.ahajournals.org/doi/10.1161/CIR.0000000000000916
DOI
10.1161/CIR.0000000000000916
ILCOR CONSENSUS ON SCIENCE AND TREATMENT RECOMMENDATIONS
https://costr.ilcor.org/
EUROPEAN RESUSCITATION COUNCIL GUIDELINES 2021
CARDIAC ARREST IN SPECIAL CIRCUMSTANCES
https://cprguidelines.eu/
DOI
10.1007/S10049-021-00896-5
SOCIETY FOR MATERNAL FETAL MEDICINE
MATERNAL CARDIAC ARREST
https://www.smfm.org/
AMERICAN COLLEGE OF OBSTETRICIANS AND GYNECOLOGISTS
CARDIAC ARREST IN PREGNANCY
https://www.acog.org/
AUQUI-VALAREZO ET AL.
CARDIOPULMONARY AND CEREBRAL RESUSCITATION IN PREGNANCY
GINECOLOGIA Y OBSTETRICIA DE MEXICO 2023
https://ginecologiayobstetricia.org.mx/
EXTRAHOSPITAL OBSTETRIC DELIVERY MANUAL
SPANISH MINISTRY OF HEALTH
https://emssolutionsint.blogspot.com/2014/01/manual-de-atencion-al-parto-en-el.html
ILCOR GUIDELINES 2025
https://emssolutionsint.blogspot.com/2025/10/guias-ilcor-2025.html
AHA EXECUTIVE SUMMARY 2020
https://emssolutionsint.blogspot.com/2020/10/executive-summary-2020-international.html
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