A Rare Case of Symptomatic Eventration of Right Hemidiaphragm Secondary to Ascites

Introduction: Diaphragmatic eventration, a permanent elevation of the diaphragm caused by thinning, is a rare phenomenon in adults. Acquired cases are due to etiologies that result in phrenic nerve injury and muscle atrophy, such as trauma, infection, neoplasm and neuromuscular disorders. Most adults are asymptomatic. We present the first reported case of an adult with chest pain and dyspnea due to right hemidiaphragm eventration in the setting of ascites. Case Description/Methods: A 43-year-old male with history of decompensated alcoholic cirrhosis, ascites and hepatorenal syndrome presented with chest pain and dyspnea that began hours after dialysis. He had notable hypotension (75/42 mmHg), jaundice, and distended, tender abdomen. Labs were notable for negative troponin, elevated BNP, leukocytosis, anemia, thrombocytopenia, elevated creatinine, BUN and liver enzymes. Diagnostic paracentesis was negative for spontaneous bacterial peritonitis. Chest radiography showed elevation of the right hemidiaphragm. CT angiogram demonstrated significant trapped subdiaphragmatic and suprahepatic ascites, large right hemidiaphragm eventration, and consequently severe compressive atelectasis of the right lung (to less than half of its normal volume) with mass effect upon right atrium. Ultrasound showed fluid in subdiaphragmatic region communicating with abdominal cavity without safe window for aspiration. Echocardiogram revealed right atrial compression due to ascites. Hospital course was complicated by refractory hypotension, which improved with 4 liters paracentesis from subhepatic region and a combination of IV fluids, albumin, midodrine, hydrocortisone and vasopressors. His symptoms also improved after paracentesis. Discussion: To our knowledge, this is the first reported case of diaphragmatic eventration due to ascites. The retained subdiaphragmatic fluid might be due to intraabdominal pressure forcing it into the potential space created with diaphragm eventration. Hypotension, attributed to reduced preload as the diaphragm compressed on IVC and right atrium, was amplified by vasodilation from cirrhosis. The combination of large volume ascites with weak diaphragmatic muscle or prior trauma can lead to eventration and profound hypotension. Fluoroscopic sniff test can be used to distinguish diaphragm eventration from paralysis. Treatment consists of supportive care and, in some cases, surgical plication of the diaphragm. Frequent paracentesis or early intervention with fluid aspiration may prevent hemodynamic collapse.Figure 1.: a) Chest radiograph demonstrating elevation of the right hemidiaphragm and bibasilar atelectasis b) CT angiogram demonstrating subdiaphragmatic and suprahepatic ascites, large right hemidiaphragm eventration, and severe compressive atelectasis of the right lung c) Transthoracic echocardiogram displaying the right atrium compression from ascites.