What are the potential surgical complications that can occur during pregnancy?

Surgical Complications During Pregnancy

Cardiovascular Complications

Aortic dissection and rupture represent the most catastrophic surgical complications during pregnancy, particularly in women with underlying aortic pathology. 1

High-Risk Aortic Conditions

• Marfan syndrome patients face the highest risk of spontaneous aortic dissection or rupture during pregnancy, especially in the third trimester or near delivery. 1 This can occur at any aortic root size, though risk is particularly elevated when the ascending aorta exceeds 45 mm. 1

• Aortic dissection in Marfan syndrome can occur without preceding dilatation, making all pregnant women with this condition high-risk regardless of baseline measurements. 1

• Ehlers-Danlos syndrome type IV carries extreme risk of large vessel rupture and uterine rupture during pregnancy, making it a contraindication to pregnancy. 1 Surgical repair in these patients is complicated by tissue fragility, extensive hemorrhage tendency, and poor wound healing. 1

• Coarctation of the aorta increases risk of aortic rupture and cerebral aneurysm rupture during pregnancy and delivery, particularly in unrepaired cases or those with residual hypertension. 1 Rupture of the aorta is the most commonly reported cause of death in these patients. 1

• Bicuspid aortic valve is associated with aortic dilatation and dissection risk, requiring pre-pregnancy imaging and consideration of surgery when the aortic diameter exceeds 50 mm. 1

Cardiac Surgical Complications

• Cardiac valve surgery during pregnancy carries high incidence of fetal distress, growth retardation, or fetal loss even under optimal cardiopulmonary bypass conditions. 1 Surgery should only be pursued for medically refractory cardiac symptoms, especially with low-output syndrome. 1

• Maternal complications from cardiac surgery occur in 20.9% of open procedures and 6.2% of fetoscopic procedures, with serious maternal complications in 4.5% and 1.7% respectively. 1

Obstetric and Wound-Related Complications

Uterine Complications

• Uterine rupture occurs in 9.6% of subsequent pregnancies after open fetal surgery, comparable to rates after classical cesarean delivery. 1

• Women with Ehlers-Danlos syndrome type IV face risk of uterine rupture during pregnancy due to tissue fragility. 1

Wound Healing and Future Pregnancy Risks

• Pregnancy within the first year after major abdominal surgery increases risk of wound dehiscence and hernia formation due to increased intra-abdominal pressure stressing healing tissues. 2

• Complete fascial healing takes approximately 6-12 months after major abdominal surgery, and pregnancy should be delayed 12-18 months to allow proper healing. 2

• After open fetal surgery, 20% of subsequent pregnancies result in pregnancy loss before 24 weeks, compared to 13.7% after fetoscopic surgery. 1

Anesthetic and Perioperative Complications

Aspiration Risk

• Pregnancy-associated gastroesophageal reflux increases aspiration risk during surgery, requiring special airway management precautions. 3, 4

Hemodynamic Complications

• Maternal hypotension can cause reduced placental blood flow and fetal hypoxia, making maintenance of adequate maternal oxygenation and optimal uteroplacental perfusion critical throughout procedures. 5, 3, 4

• Aortocaval compression occurs in pregnant women after 20 weeks when supine, necessitating left uterine displacement during surgery. 3

• Strategies to avoid hypoxemia, hypotension, acidosis, and hyperventilation are critical elements of anesthetic management. 3

Laparoscopic-Specific Risks

• Laparoscopic procedures during pregnancy require specific modifications to minimize complications: operative time limited to 90-120 minutes, low intra-abdominal pressure (10-13 mmHg), and open introduction technique. 3

Thromboembolic Complications

• Pregnant patients undergoing surgery are at very high risk for venous thromboembolism, requiring risk assessment and consideration of low-molecular-weight heparin and pneumatic compression. 5

Fetal Complications

Direct Surgical Impact

• Fetal distress, growth retardation, and fetal loss are common complications of maternal cardiac surgery, even with optimal cardiopulmonary bypass techniques. 1, 6

• Three of eleven pregnancies (27%) resulted in intrauterine demise within one week of aortic surgery in one series, despite appropriate monitoring and technique. 6

Timing-Related Risks

• Surgery between weeks 3-5 post-conception may be associated with neural tube defects, though anesthesia and surgery remain safe if medically indicated during the first trimester. 5

• Prematurity rates reach 20-30% and intrauterine growth retardation 5-20% in women with moderate to severe mitral stenosis. 1

Medication-Related Complications

Anticoagulation Risks

• Heparin exposure during pregnancy did not show evidence of increased risk of adverse maternal or fetal outcomes in humans, though preservative-free formulations are recommended when available. 7

• Benzyl alcohol preservative in heparin can cause serious adverse events and death when administered to neonates and infants, making preservative-free formulations essential during pregnancy and lactation. 7

Analgesic Complications

• NSAIDs after 28 weeks gestation may cause premature closure of the fetal ductus arteriosus and oligohydramnios, especially if administered for more than 48 hours. 5

• Paracetamol is the first-line analgesic for mild to moderate pain during any stage of pregnancy at doses of 975 mg every 8 hours or 650 mg every 6 hours. 5, 3

Maternal Mental Health Complications

• Women with fetuses with anomalies requiring surgery have significantly higher rates of anxiety (mean state anxiety score 43.6 vs 29.1 in uncomplicated pregnancies). 1

• 5.5% of women with pregnancy complicated by fetal anomaly are at high risk of traumatic stress and 35.9% at elevated risk of major depression in the immediate postpartum period. 1