Rectus sheath hematoma associated with commencement of therapeutic low molecular weight heparin injections: a case report

BACKGROUND: Subcutaneous low molecular weight heparin is a commonly used anticoagulant. Catastrophic hemorrhage is a known adverse outcome associated with anticoagulant use. Of all potential bleeding sites, hemorrhage into the rectus sheath is a rare and unusual complication. In this case report, we document a patient who developed rectus sheath hematoma following new commencement of therapeutic low molecular weight heparin. CASE PRESENTATION: A 71-year-old New Zealand European woman presented to a peripheral hospital with suspected unstable angina. She was started on therapeutic subcutaneous low molecular weight heparin. While awaiting inpatient transfer to a tertiary hospital for coronary angiography, she developed a large rectus sheath hematoma associated with hemodynamic instability. She required an urgent laparotomy to decompress the hematoma and achieve hemostasis. Postoperatively, her anticoagulation therapy was stopped, and she made a full recovery. CONCLUSION: Rectus sheath hematoma is a condition that is difficult to diagnose. The risk of adverse events must always be considered against the indication and potential benefits of new medications, especially with high-risk medications such as anticoagulants.