The Pregnant Patient With Abdominal Pain and a Rising Heart Rate
A 26-year-old woman at 28 weeks' gestation presents with 6 hours of right lower quadrant and periumbilical pain, nausea, and one episode of vomiting. Vitals: HR 112, BP 108/66, RR 20, Temp 37.9°C, SpO2 99%. She is tender in the right lower quadrant with voluntary guarding. Fetal heart rate is 150. WBC 14.5, hemoglobin 11.2. Urine pregnancy test is positive (known). Bedside ultrasound shows a live intrauterine fetus. She is anxious and asks whether imaging will hurt the baby.
1. How do you approach imaging and diagnosis in this pregnant patient with suspected appendicitis?
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Do not withhold necessary imaging out of fear of fetal harm. The differential includes appendicitis (which can be atypical in pregnancy as the appendix is displaced superiorly), ovarian torsion, pyelonephritis, and preterm labor. Start with graded compression ultrasound by an experienced sonographer; if nondiagnostic, MRI without gadolinium is preferred over CT when available. CT with shielding can be used if MRI is unavailable and the diagnosis is critical, because a missed appendicitis with perforation is far more dangerous to mother and fetus than the radiation dose. Communicate risks and benefits to the patient. The judgment call is avoiding diagnostic paralysis while choosing the modality with the best risk-benefit profile.
2. Ultrasound is nondiagnostic. What factors determine your next step, and how do you counsel her?
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Factors: availability of MRI, hemodynamic stability, severity of symptoms, and the pretest probability. With stable vitals and a nondiagnostic US, MRI is the next best test. Counsel that MRI without contrast has not been shown to harm the fetus, that untreated appendicitis risks perforation, sepsis, and preterm labor, and that the risk of missing the diagnosis outweighs imaging risk. If she remains unstable or has peritonitis, proceed directly to surgical consultation and CT if needed. Document the shared decision. The judgment call is framing relative risk honestly rather than offering false reassurance.
3. The patient is diagnosed with appendicitis and is taken to the operating room. Postoperatively she develops tachycardia and hypotension. What is your differential and immediate management?
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Differential: hemorrhage, sepsis (perforation), pulmonary embolism (pregnancy is prothrombotic), and anesthetic complications. Immediate management: ABCs, two large-bore IVs, fluids, type and screen/crossmatch, and bedside assessment including FAST for free fluid. Notify surgery and obstetrics. Monitor fetal status. If hemorrhage, activate massive transfusion as needed; if sepsis, cultures and antibiotics; if PE suspected, consider CT pulmonary angiography with shielding after stabilization. The judgment call is not anchoring on postoperative pain but treating new instability as a potentially catastrophic complication.