What is the management approach for sudden collapse in pregnant women with cardiac conditions during the golden hour?

Management of Sudden Collapse in Pregnant Women with Cardiac Conditions During the Golden Hour

For pregnant women experiencing sudden cardiac collapse, immediately initiate high-quality CPR with the patient supine, perform continuous manual left uterine displacement if fundal height is at or above the umbilicus, and prepare for perimortem cesarean delivery at 4 minutes if no return of spontaneous circulation (ROSC) is achieved. 1, 2

Immediate Resuscitation Priorities (First 4 Minutes)

Patient Positioning and Chest Compressions

• Place the patient supine on a firm surface and begin standard chest compressions immediately—do not use left lateral tilt positioning as it significantly reduces coronary perfusion pressure (20 mm Hg supine vs 5 mm Hg with tilt). 1
• If the fundus height is at or above the umbilicus (approximately ≥20 weeks gestation), perform continuous manual left uterine displacement by pulling the uterus to the left to relieve aortocaval compression while maintaining supine positioning for optimal chest compressions. 1, 2
• Use standard compression-ventilation ratio of 30:2 with compressions at standard depth and rate. 2

Airway and Oxygenation

• Provide early bag-mask ventilation with 100% oxygen at ≥15 L/min to ensure adequate maternal and fetal oxygenation. 2
• Insert a nasogastric tube in semiconscious or unconscious patients to prevent aspiration of acidic gastric content, as pregnant women are at higher risk. 3
• Maintain maternal oxygen saturation >95% to ensure adequate fetal oxygenation. 3

Vascular Access and Medications

• Establish two large bore (14-16 gauge) intravenous lines immediately. 3
• Follow standard ACLS protocols for medication administration—pregnancy does not alter drug dosing or contraindicate standard resuscitation medications. 1
• Use vasopressors only for intractable hypotension unresponsive to fluid resuscitation due to adverse effects on uteroplacental perfusion. 3

Critical Decision Point at 4 Minutes

Perimortem Cesarean Delivery (PMCD)

• Summon resources for PMCD immediately upon recognition of cardiac arrest in any pregnant woman in the second half of pregnancy (≥20 weeks gestation or fundus at/above umbilicus). 1
• Begin PMCD at 4 minutes after onset of cardiac arrest if no ROSC is achieved—this timing is critical for both maternal resuscitation (by relieving aortocaval compression and improving venous return) and fetal salvage. 1, 2, 3
• PMCD should be performed at the site of arrest without delaying for transport to the operating room. 2
• In cases of nonsurvivable maternal trauma or prolonged pulselessness where maternal resuscitation is futile, perform PMCD immediately without waiting 4 minutes. 1

Evidence Supporting PMCD Timing

• Maternal survival has been documented up to 15 minutes after cardiac arrest onset, and neonatal survival up to 30 minutes, but outcomes are significantly better with earlier delivery. 1
• PMCD improves maternal resuscitation by relieving aortocaval compression and increasing cardiac output by 25-30%. 4, 3

Diagnosis of Underlying Cardiac Conditions

Common Causes of Sudden Collapse in Pregnancy

• Pulmonary embolism (PE) is the leading cause of pregnancy-related mortality in developed countries, accounting for 20% of maternal deaths. 2

  • PE presents with pulseless electrical activity in 36-53% of cases; primary shockable rhythms are uncommon. 1
  • Consider thrombolysis for confirmed massive PE causing cardiac arrest—the same indications apply as in non-pregnant women. 5

• Amniotic fluid embolism (AFE) should be considered in any laboring or recently delivered woman with sudden cardiorespiratory collapse. 1

  • AFE is a clinical diagnosis of exclusion with no specific diagnostic test available. 1
  • Coagulopathy frequently follows cardiovascular collapse—assess clotting status early and initiate massive transfusion protocols. 1

• Peripartum cardiomyopathy should be ruled out in women presenting with new-onset ventricular tachycardia during the last 6 weeks of pregnancy or postpartum period. 1, 6

• Acute coronary syndrome occurs in 1.5-10 per 100,000 deliveries with 5-10% maternal mortality, most commonly from spontaneous coronary artery dissection. 2

Diagnostic Approach During Resuscitation

• Perform bedside echocardiography during CPR to identify reversible causes such as right ventricular strain (suggesting PE), severe left ventricular dysfunction, or pericardial tamponade. 5
• Do not delay resuscitation or PMCD to obtain diagnostic studies. 1

Post-ROSC Management

Immediate Stabilization

• Continue 100% oxygen and maintain oxygen saturation >95%. 2, 3
• Avoid excessive fluid administration—pregnant women are at risk for pulmonary edema post-resuscitation. 1
• Assemble a multidisciplinary team including critical care, cardiology, maternal-fetal medicine, and anesthesia. 1

Specific Interventions Based on Etiology

• For confirmed PE: Administer thrombolysis if massive PE with hemodynamic instability; prepare for massive transfusion and potential hysterectomy if uterus cannot contract post-delivery. 5
• For AFE: Initiate massive transfusion protocol early; provide respiratory support with mechanical ventilation and hemodynamic support with vasopressors, inotropes, and pulmonary vasodilators. 1
• For acute coronary syndrome: Proceed with diagnostic coronary angiography and primary PCI using bare metal stents only; avoid drug-eluting stents. 2

Critical Pitfalls to Avoid

• Do not use left lateral tilt for CPR positioning—it significantly reduces chest compression effectiveness. 1
• Do not delay PMCD beyond 4 minutes waiting for ROSC or for transport to the operating room. 1, 2
• Do not withhold thrombolysis for massive PE in pregnancy—maternal mortality risk far outweighs bleeding risks. 5
• Do not delay diagnostic imaging or interventions due to radiation concerns—maternal mortality risk far exceeds fetal radiation risk. 2
• Do not use ergometrine in the third stage of labor or post-PMCD—it is contraindicated in cardiac patients. 7

Team Preparation Requirements

• All centers caring for pregnant women must have standard institutional protocols for maternal cardiac arrest that are regularly practiced. 1
• Ensure immediate availability of equipment and personnel for PMCD at the bedside within 4 minutes. 1
• Establish clear communication pathways to rapidly assemble multidisciplinary teams. 1, 4