Dyspnea in a Cirrhotic: Donʼt Forget About Hepatopulmonary Syndrome

Abstract

Case Report: A 44 year old Caucasian female with a history of alcohol induced cirrhosis, esophageal varices, hepatic encephalopathy, and COPD presented to the emergency department with a chief complaint of nausea, emesis, and flank pain. The patient was admitted with pyelonephritis, however, she endorsed concomitant shortness of breath, dyspnea on exertion, and platypnea. On physical examination, the patient was found to have fixed splitting of the second heart sound and significant clubbing present on all four extremities. A transthoracic echocardiogram with bubble study was performed which demonstrated a pulmonary shunt and arterial blood gas analysis showed a calculated alveolar-arterial gradient of 22. The aforementioned historical, physical examination, and laboratory findings including portal hypertension, pulmonary shunt, and elevated A-a gradient culminated in a diagnosis of hepatopulmonary syndrome. Discussion: Chronic liver disease has been shown to lead to the development of several pathologic processes throughout the body. Hepatopulmonary syndrome represents the most common pulmonary complication, with a prevalence of 5-30% in cirrhotics.In HPS, pulmonary pre-capillary and capillary dilatation leads to arterial hypoxemia via a ventilation-perfusion mismatch, impaired diffusion, and shunting. This typically manifests as dyspnea, platypnea, orthodeoxia, and clubbing.Platypnea and orthodeoxia are defined as an increase in dyspnea(platypnea) or a decrease in the arterial partial pressure of oxygen(orthodeoxia) with positional change from supine to upright. These physical exam findings should be recognized by the astute bedside physician and are manifestations of the ventilation-perfusion mismatch seen in HPS. The presence of platypnea and/or orthodeoxia should prompt further evaluation of any cirrhotic patient reporting dyspnea. Diagnosis is made by observation of the following: Liver disease, Alveolar-arterial gradient ≥15 mmHg or ≥20 mmHg in patients > 64 years of age, and the presence of intrapulmonary shunting. It is important to note that portal hypertension is not a prerequisite for the diagnosis of HPS.Intrapulmonary shunting is demonstrated with the use of either contrast-enhanced echocardiography demonstrating the rapid appearance of microbubbles in the left atrium after intravenous injection or macroaggregated albumin radioactive lung perfusion scan showing the presence of radiolabeled particles in the brain, spleen, or kidneys.Definitive treatment for HPS is liver transplantation and patients with HPS are given MELD exception points. Oxygen is typically utilized for symptomatic relief but HPS is associated with an increased mortality when compared to unaffected patients with liver disease.