Pneumomediastinum a Rare Complication of Colonoscopy Polypectomy Successfully Treated With Conservative Management

Abstract

Colonoscopies are a relatively safe and are associated with few complications. We present a rare case of post-colonoscopy polypectomy resulting in a pneumomediastinum and subcutaneous emphysema. Case Report: An 84 year old male with a history of colonoscopy with polypectomy the day prior was admitted due to a syncopal episode. The only complaint was a small amount of dark red blood per rectum. On examination vital signs were stable, the patient appeared pale with dry membrane mucosa, abdominal and pulmonary exam were benign, labs were concerning for a Hgb 6.9 g/dl. Chest x-ray depicted free air beneath the right hemidiaphragm, computed tomography (CT) demonstrated pneumoretroperitoneum, pneumomediastinum and subcutaneous emphysema. Visceral angiogram failed to demonstrate any source of active bleeding. Due to the overall stable condition of the patient conservative management with prophylactic zosyn and transfusion of 2 units of packed red blood cells was initiated. Patient was discharged 5 days after admission with stable respiratory and hemodynamic signs. Discussion: Diagnostic colonoscopies are relatively safe procedures with the most common complications being bleeding and perforations, with an incidence of less than.2%. Though perforations are rare they are associated with a high mortality and morbidity. Causes of perforation can be due to excessive insufflations and instrumental trauma and usually present with intra-abdominal free air but rarely with a pneumomediastinum. A pneumomediastinum is the presence of free air within the mediastinum and in our case was due to a micro-perforation from a colonic polypectomy. The colonic wall defect allowed free air into the retroperitoneum, which spread along the fascial planes and entered the mediastinum and subcutaneous tissues. The most sensitive test for pneumomediastinum is computed tomography and extra-pulmonary causes of pneumomediastinum can be successfully treated conservatively with rest and antibiotics. Though complications from polypectomies are rare, they can be associated with a high morbidity and mortality but rarely associated with pneumomediastinum and in certain stable patients can be treated with conservative management.Figure 1Figure 2