Perimortem C-section Summary

Definition

  • Emergency C-section during maternal cardiac arrest
  • Considered when initial resuscitation fails
  • Goal: Improve maternal and fetal survival

Critical Timeframe

  • Best outcomes: Delivery within 5 minutes of arrest
  • Consider early - within 4 minutes of arrest
  • Decision should not delay ongoing CPR

Gestational Age Criteria

  • <20 weeks: Do not perform
  • 20-23 weeks: For maternal benefit only
  • >24 weeks: For maternal and fetal benefit

Physiological Benefits

  • Relieves IVC compression
  • Improves venous return during CPR
  • Enables aortic clamping/compression
  • Allows internal cardiac massage

Gestational Age Estimation

  • Umbilicus level = 20 weeks
  • +1 cm/week after 20 weeks
  • Fundal height assessment crucial

Procedure Steps

  • Midline vertical incision
  • Vertical uterine incision
  • Rapid fetal delivery
  • Immediate neonatal resuscitation
  • Continue maternal resuscitation

Key Points

  • Do not delay maternal CPR
  • Have neonatal team ready
  • Continue maternal resuscitation post-delivery
  • Time is critical for both patients

Perimortem Caesarean Delivery

Emergency delivery during maternal cardiac arrest to improve resuscitation outcomes

Overview

Perimortem caesarean delivery is a consideration for women who suffer cardiac arrest in pregnancy. When initial resuscitation attempts fail, delivery of the foetus may improve the chances of successful resuscitation of both the mother and the foetus.

Time Critical: The best survival rate for infants over 24-25 weeks gestation occurs when delivery is achieved within 5 minutes after maternal cardiac arrest.

Pathophysiology

Delivery relieves inferior vena cava (IVC) compression and may improve the likelihood of resuscitating the mother by permitting an increase in venous return during CPR attempts.

Maternal Benefits

  • Relieves IVC compression: Improves venous return to heart
  • Enables aortic access: Permits aortic clamping or compression
  • Facilitates cardiac massage: Internal cardiac massage becomes possible
  • Improves CPR efficacy: Better chest compression quality

Fetal Benefits

  • Immediate resuscitation: Enables dedicated neonatal care
  • Prevents hypoxic injury: Reduces prolonged fetal hypoxia
  • Optimal timing: Best outcomes when delivered within 5 minutes

Critical Timeframe: Consider perimortem caesarean section at an early stage after cardiac arrest. The 5-minute window is difficult to achieve but should be the target.

Indications and Gestational Age

Gestational Age Assessment

First, estimated gestational age (EGA) should be determined either based on history or fundal height. In general, the uterus reaches the level of the umbilicus at 20 weeks and grows approximately 1 centimeter for every week thereafter.

Fundal Height Gestational Age
At umbilicus 20 weeks
Midway umbilicus-xiphoid 24 weeks
At xiphoid process 36 weeks

Decision Guidelines

Gestational Age < 20 weeks

  • Do not consider emergency delivery
  • Gravid uterus of this size is unlikely to compromise maternal cardiac output
  • Focus on maternal resuscitation only

Gestational Age 20 - 23 weeks

  • Initiate emergency delivery for maternal benefit only
  • Fetus not yet viable
  • Procedure performed to improve maternal resuscitation chances

Gestational Age > 24 weeks

  • Initiate emergency delivery for both mother and infant
  • Fetus considered potentially viable
  • Best outcomes when delivered within 5 minutes of arrest

Physiological Basis: In the supine position, the gravid uterus begins to compromise blood flow in the inferior vena cava (IVC) and abdominal aorta at approximately 20 weeks gestation; however fetal viability begins at approximately 24 weeks.

Procedure

Team Preparation: Ensure neonatal resuscitation team is ready before starting the procedure. Continue maternal CPR throughout.

Step-by-Step Procedure
  1. Midline Incision
    • Make a midline incision from the level of the fundus to the pubic symphysis
    • Use retractors to gain exposure to the uterus
  2. Enter Peritoneum
    • Perform blunt dissection until the peritoneum is entered
    • Identify the gravid uterus
  3. Uterine Incision
    • Make a vertical incision from the fundus inferiorly towards the anterior bladder reflection
    • Avoid bladder injury
  4. Protect Fetus
    • When the uterine cavity is first entered, insert middle and index fingers
    • Lift the uterine wall away from the infant
    • Extend the incision with scissors while protecting the fetus
  5. Deliver Infant
    • Deliver the infant through the hysterotomy
    • Immediately hand to neonatal resuscitation team
    • Clamp and cut the cord
  6. Complete Procedure
    • Remove the placenta
    • Continue maternal resuscitative efforts
    • Consider uterine closure if maternal circulation returns

Special Considerations

Maternal Resuscitation

  • Continue CPR throughout the procedure
  • Do not interrupt chest compressions
  • Consider internal cardiac massage after delivery
  • Aortic compression may be beneficial

Neonatal Care

  • Have neonatal team prepared before starting
  • Immediate resuscitation of newborn
  • Consider gestational age in resuscitation decisions
  • Document time of delivery clearly

Timeline and Decision Making

Rapid Decision Framework: The decision to perform perimortem caesarean should be made within 4 minutes of cardiac arrest if there is no response to initial resuscitation.

Time After Arrest Action
0-1 minute Initiate standard maternal CPR
Call for help including obstetric and neonatal teams
1-4 minutes Assess gestational age
Prepare for possible perimortem C-section
Continue aggressive resuscitation
4-5 minutes If no ROSC and gestation >20 weeks
BEGIN PERIMORTEM C-SECTION
5 minutes Target for delivery completion
Simultaneous maternal and neonatal resuscitation

Team Roles and Responsibilities

Resuscitation Team

  • Continue high-quality CPR
  • Manage airway and ventilation
  • Administer medications per ACLS protocols
  • Coordinate overall resuscitation effort

Obstetric Team

  • Perform perimortem caesarean delivery
  • Estimate gestational age
  • Manage uterine closure if indicated
  • Provide obstetric expertise

Neonatal Team

  • Ready for immediate neonatal resuscitation
  • Assess gestational age of newborn
  • Provide appropriate neonatal care
  • Coordinate neonatal transport if needed

Outcomes and Prognosis

Maternal Outcomes

  • Improved ROSC rates after delivery
  • Better hemodynamics during CPR
  • Potential for full neurological recovery
  • Successful cases reported even after prolonged arrest

Neonatal Outcomes

  • Best outcomes with delivery within 5 minutes
  • Gestational age crucial for survival
  • Good neurological outcomes reported
  • Importance of immediate neonatal resuscitation

Medicolegal Considerations: Perimortem caesarean delivery is a life-saving procedure for both mother and fetus. The benefits generally outweigh the risks in appropriate candidates. Document decision-making process clearly.

Key Success Factors