B49-37 An Insidious Obstruction: Acute Cardiorenal and Hepatic Injury as the Unmasking of an Occult Tamponade: A Case Report

Abstract Introduction Cardiac regional tamponade caused by an organized hematoma is an uncommon yet, dangerous postoperative complication, which if not recognized in a timely fashion may result in significant morbidity and mortality. We report a unique presentation of normotensive concealed obstructive shock caused by a hematoma around the right atrium leading to multi-system failure. Case Description A 49-year-old male patient with history of non-rheumatic severe aortic valve insufficiency, underwent mechanical Aortic valve replacement along with Left atrial appendage clipping. Initial postoperative course was uneventful with timely extubation, mediastinal tubes removal and initiation of heparin on post operative day (POD) 1 for the mechanical aortic valve with subsequent transfer out of ICU. On POD 7, patient developed oliguric acute kidney injury (AKI), ischemic hepatitis with transaminitis. Review of patient’s hemodynamics revealed mean arterial pressures ( MAP ) never dropped to 65. Repeat blood work on POD 8 showed worsening leukocytosis, lactic acidosis in addition to progressive renal failure. A transthoracic echocardiogram (TTE) performed two days prior was only showing a trace effusion. As end-organ failure worsened, critical care medicine was consulted, a point-of-care ultrasound (POCUS) bedside revealed a large, organized hematoma along the right atrial free wall causing complete right atrial collapse in diastole with underfilled and hyperdynamic left ventricle. The patient was urgently taken back to surgery for mediastinal re-exploration with intra-operative confirming right atrial compression. Post-operatively, patient was extubated and immediate improvement was noted in urine output and cardiac function, with subsequent down trending of other deranged labs, leading to a discharge from the intensive care unit two days later. Discussion This particular case illustrates recognition of normotensive shock , or “occult hypoperfusion,” through signs like hyperlactatemia, acute kidney injury, ischemic hepatitis and afebrile marked leukocytosis, which are markers of acute stress rather than just blood pressure. Bedside POCUS was critical in establishing this diagnosis when algorithmic approaches failed to identify it. This particular case is unique in that it confirms that limited or regional hematoma with compressive features on even one of the cardiac chambers is enough to cause a significant hemodynamic catastrophe similar to a circumferential effusion. Moreover, it serves as a reminder that in setting of high suspicion for a hematoma—surgical, rather than a percutaneous approach should be opted for, to avoid fatal delay in necessary treatment. The key points are the need for prompt recognition of shock, the use of POCUS, and immediate surgical intervention. This abstract is funded by: None