Bilateral Rectus Sheath Hematoma Developing During Anticoagulant Therapy
A 74-year-old woman presented with severe progressively worsening abdominal pain after defecation. She had been diagnosed as having unstable angina and had been given 100 mg aspirin and started on a therapeutic dose of heparin and nitroglycerin infusion. At the time of presentation, physical examination revealed a painful large mass in the lower abdominal quadrants extending bilaterally, with no skin discoloration. The blood pressure was 80/50 mm Hg, and the pulse rate was 80 bpm while the patient was receiving oral β-blocker therapy. Her hemoglobin dropped from 13.4 to 9.4 g/dL, and the activated partial thromboplastin time was 61.7 seconds. Computed tomography of the abdomen without contrast (Figure 1A) showed a huge bilateral rectus sheath hematoma measuring 15.5×12.5×7.5 cm with a fluid-fluid level. Contrast-enhanced computed tomography (Figure 1B) showed extravasation of the contrast material within the hematoma from the bilateral inferior epigastric arteries. Despite fluid resuscitation, injection of protamine 30 mg, and red blood cell transfusion, the blood pressure remained low. The abdominal mass continued to grow, and the symptoms worsened. The patient was referred to our radiology department for possible intervention at the bleeding sites. Digital subtraction angiography showed multiple active bleeding foci from the inferior epigastric arteries bilaterally (Figure 2). Therefore, percutaneous arterial embolizations were performed, and her blood pressure became stable. The hematoma gradually decreased in size, and the patient was later discharged home. A follow-up computed tomographic examination without contrast performed 5 months later (Figure 3) showed partial resorption of the hematoma.
Rectus sheath hematoma is a rare but important cause of abdominal pain. Anticoagulation has been described as an important causative factor.1–3 Other rarer associations include abdominal trauma, previous surgery, asthma, stretching, hypertension, pregnancy, intraabdominal injection, and iatrogenic causation during laparoscopy.3 Rectus sheath hematoma most typically occurs after a bout of coughing. It shows a female predominance and is usually unilateral.3 Reports of bilateral rectus sheath hematoma are rare. Patients with rectus sheath hematoma typically present with a sudden onset of severe abdominal pain and an immobile anterior abdominal wall mass. The diagnosis of rectus sheath hematoma may be made by abdominal ultrasonography, computed tomography, or magnetic resonance imaging. Computed tomography of the abdomen and pelvis is the most commonly used method to establish the diagnosis.3 Rectus sheath hematomas occur secondary to tearing of branches of the superior or inferior epigastric arteries or of the rectus muscle fibers. Although most are self-limited as the bleeding stops itself, some patients show significant morbidity, and the overall mortality is reported as 4%. For those receiving anticoagulation therapy, the mortality rate has been reported to be as high as 25%.4
Conservative management is the most commonly used treatment for rectus sheath hematoma. The role of surgery in the management of rectus sheath hematoma is difficult to ascertain because surgery was performed for incorrect diagnoses in many patients, mainly because of confusion of rectus sheath hematoma with intraabdominal problems.5 The indications for angiography and further arterial embolization are persistent bleeding and hemodynamic instability despite reversal of anticoagulation and conservative management with fluids, fresh frozen plasma, and red blood cell transfusion.5