Surgery During Pregnancy

Pregnancy's Surgical Stage - Bump's Big Day Prep

• Physiological Adaptations for Surgery:
  • Cardio: ↑ Cardiac Output (CO), ↓ Systemic Vascular Resistance (SVR).
  • Respiratory: ↓ Functional Residual Capacity (FRC), ↑ O2 consumption.
  • GI: ↓ motility, ↓ Lower Esophageal Sphincter (LES) tone (↑ reflux/aspiration risk).
  • Hematologic: Hypercoagulable state, physiological anemia.
• Surgical/Anesthetic Impact:
  • Mother: Aspiration, Deep Vein Thrombosis (DVT).
  • Fetus: Hypoxia, acidosis, preterm labor; Intrauterine Growth Restriction (IUGR) if prolonged/severe stress.
• Teratogenic Risks:
  • Critical period (drugs/radiation): 3-8 weeks post-conception.
  • Radiation exposure: <5 rads generally considered safe.

⭐ Progesterone-induced ↓GI motility & ↓LES tone significantly ↑ aspiration risk during anesthesia in pregnant patients.

The Pre-Op Puzzle - Timing Triumphs Tests

• Optimal Timing: Second Trimester (14-26 wks)
  • Why: Organogenesis complete, ↓ spontaneous abortion risk, ↓ preterm labor risk. Uterus size manageable.
• Indications & Urgency:
  • Urgent (e.g., appendicitis, trauma): Surgery ASAP.
  • Non-urgent: Postpone postpartum if possible; if not, target 2nd trimester.
• Maternal Pre-Op Assessment:
  • Standard surgical workup.
  • Obstetric considerations: Gestational Age (GA), comorbidities (e.g., GDM, PIH), baseline Fetal Heart Rate (FHR).
• Fetal Pre-Op Assessment:
  • Ultrasound: Confirm viability, GA, anatomy, placental location.
  • If viable fetus & GA > 24 wks: Consider Non-Stress Test (NST) / Biophysical Profile (BPP).
• Informed Consent:
  • Discuss maternal & fetal risks (anesthesia, surgery).
  • Alternatives to surgery.
  • Risk of preterm labor/delivery.
  • Potential need for obstetric interventions (e.g., tocolysis, steroids, C-section).

⭐ > The second trimester is generally the safest period for non-urgent surgery in pregnant women.

Anesthesia & Intra-Op - Safe Sleep, Scalpel Smart

• Goals: Maternal safety, fetal well-being (uterine perfusion, avoid hypoxia/hypotension/acidosis), uterine quiescence.
• Choice: Regional (spinal/epidural) > GA (↓ fetal drug exposure & aspiration risk).
  • GA for: Emergencies, regional C/I, complex/long surgery.
• Drugs:
  • Avoid NSAIDs 3rd trimester (premature ductal closure).
  • Benzos: Cleft risk (1st tri), neonatal effects.
  • Opioids: Neonatal respiratory depression.
  • Prefer: Short half-life, high protein binding.
• Positioning: 📌 LUD (Left Uterine Displacement) after ~18-20 wks (prevents aortocaval compression).

  ⭐ Aortocaval compression by gravid uterus reduces CO by up to 30% supine.

• Fetal Monitoring: Intermittent FHR auscultation or continuous EFM if viable; document FHR pre/post.
• Laparoscopy: Precautions:
  • Insufflation <12-15 mmHg.
  • Veress/Hasson; supraumbilical/Palmer's point (1st port).
  • Ports under vision.

Post-Op & Common Culprits - Healing Duo, Usual Suspects

• Post-operative Care:
  • Continuous Fetal monitoring (FHR, uterine activity) 4-6 hrs post-op, maternal vitals.
• Prophylactic Tocolysis:
  • Not routine. Consider if high risk (beta-mimetics, CCBs, MgSO4).
  • ⚠️ Avoid indomethacin in 3rd trimester.
• DVT Prophylaxis:
  • Early ambulation, SCDs.
  • LMWH if high risk (continue 6 wks postpartum if indicated).
• Pain Management:
  • Paracetamol first-line. Opioids (cautious, short duration).
  • ⚠️ Avoid NSAIDs late pregnancy.
• Common Non-Obstetric Surgical Conditions:
  • Appendicitis: Most common. Atypical presentation (appendix displaced ↑ & laterally). Early surgery.
  • Cholecystitis: Conservative vs surgery. Lap chole feasible (ideal 2nd trimester).
  • Ovarian Torsion: High incidence. Surgical emergency. Contralateral oophoropexy if indicated.
  • Trauma: ABCDE. Kleihauer-Betke test (Rh-negative) for RhoGAM.

⭐ Appendicitis is the most common non-obstetric surgical emergency during pregnancy, with diagnosis often delayed due to atypical symptoms.

High‑Yield Points - ⚡ Biggest Takeaways

• Optimal timing for non-urgent surgery: second trimester (14-28 weeks).
• Appendicitis: most common non-obstetric surgical emergency during pregnancy.
• Laparoscopy: generally safe; use open (Hasson) technique for initial access.
• Prophylactic tocolytics: generally not recommended.
• Maternal positioning: left lateral tilt (after 20 weeks) to avoid aortocaval compression.
• Fetal monitoring: indicated intra- and post-operatively for viable gestations.
• VTE prophylaxis: crucial due to pregnancy-induced hypercoagulable state.