Obstetric Topic 59. Pregnancy complicated by surgical diseases (appendicitis, ileus, cholelithiasis)

I. General Principles

Surgery During Pregnancy

• Principle: maternal stabilization first → fetal outcome depends mainly on maternal outcome.
• Medically necessary surgery should not be delayed because of pregnancy.
• Elective surgery: postpone until after delivery if possible; if needed during pregnancy, 2nd trimester is traditionally safest.
• Diagnosis is difficult because normal pregnancy may cause nausea, vomiting, leukocytosis, constipation and altered anatomy.
• Imaging: ultrasound first when useful; MRI if ultrasound is nondiagnostic; CT/X-ray only when needed because missed diagnosis may be more dangerous.
• Perioperative points: obstetric consultation, avoid hypoxia/hypotension, VTE prevention and fetal monitoring according to gestational age/viability.
• Laparoscopy is acceptable with an experienced team; open surgery if unstable, advanced disease or poor laparoscopic access.

II. Appendicitis

Pathophysiology and Risk

• Appendicitis: most common non-obstetric surgical emergency in pregnancy.
• Mechanism: appendiceal lumen obstruction → bacterial overgrowth → inflammation → ischemia/perforation → peritonitis.
• Delayed diagnosis increases perforation, preterm labor, fetal loss and maternal sepsis risk.

Clinical Features

• Typical: right lower abdominal pain, anorexia, nausea/vomiting, low-grade fever, tenderness, raised WBC/CRP.
• Late pregnancy: appendix displaced upward/laterally by uterus → flank, right mid-abdominal or RUQ pain possible.
• Pregnancy mimics: nausea/vomiting and leukocytosis may be physiologic; uterine contractions can mimic cramping pain.

Diagnosis and Treatment

1. Clinical suspicion + abdominal/obstetric assessment and labs (CBC, CRP, urinalysis).
2. Imaging: US → MRI if unclear; CT only if diagnosis remains uncertain and MRI is unavailable/too slow.
3. Treatment: appendectomy + IV antibiotics; laparoscopic appendectomy if feasible.

III. Mechanical Ileus / Bowel Obstruction

Etiology

• Most common cause in pregnancy: postoperative adhesions.
• Enlarging uterus stretches adhesions and displaces bowel → obstruction, volvulus or torsion risk.
• Other causes: hernia, tumor, inflammatory bowel disease stricture.

Clinical Features and Diagnosis

• Symptoms: colicky abdominal pain, distension, vomiting, constipation, no stool/flatus.
• Signs may mimic pregnancy symptoms such as nausea, constipation and abdominal distension.
• Diagnosis: clinical + labs/electrolytes + US/MRI; X-ray/CT if obstruction or perforation is suspected and diagnosis remains unclear.

Management

1. Initial: hospitalize, nil per os, IV fluids, electrolyte correction, nasogastric tube, analgesia/antiemetics, fetal/obstetric assessment.
2. Observe only if stable, partial obstruction and no ischemia/peritonitis.
3. Surgery: complete obstruction, strangulation/ischemia, perforation, peritonitis, sepsis or failure to improve.

IV. Cholelithiasis and Cholecystitis

Pathophysiology

• Pregnancy promotes gallstones: estrogen → cholesterol supersaturation; progesterone → gallbladder hypomotility → biliary stasis.
• Clinical importance: gallstones are an important cause of pancreatitis in pregnancy.

Clinical Features

• Biliary colic: episodic RUQ/epigastric pain after fatty food, radiates to back/right shoulder, nausea/vomiting.
• Acute cholecystitis: persistent RUQ pain, fever, leukocytosis and Murphy sign.
• Choledocholithiasis/cholangitis: jaundice, raised bilirubin/liver enzymes ± fever/sepsis.
• Pregnancy mimics nausea and leukocytosis, so diagnosis may be delayed.

Diagnosis

1. Ultrasound: first-line; gallstones, gallbladder wall thickening, bile duct dilation.
2. Labs: CBC, bilirubin, AST/ALT, ALP/GGT, amylase/lipase if pancreatitis suspected.
3. MRCP if common bile duct stone suspected and US is unclear; ERCP mainly when therapeutic stone extraction/stenting is needed.

Treatment

• Uncomplicated biliary colic: analgesia, hydration, antiemetics, low-fat diet; recurrence is common.
• Acute cholecystitis: admission, bowel rest, IV fluids, analgesia and antibiotics.
• Choledocholithiasis/cholangitis: ERCP with sphincterotomy/stone extraction or stent by experienced team.
• Recurrent/severe symptoms, cholecystitis or pancreatitis: laparoscopic cholecystectomy; can be done in any trimester if needed, traditionally easiest in 2nd trimester.
• Postpartum elective cholecystectomy: reasonable for mild single episode if symptoms resolve and no complications.