Severe Diastolic Dysfunction Following Prolonged Extracorporeal Membrane Oxygenation in a Pediatric Burn Patient

Abstract

INTRODUCTION: A previously healthy 3-year-old female was admitted following a 22% TBSA scald burn. She was initially hemodynamically stable on room air. However, one week into hospitalization she developed ARDS with catecholamine-refractory shock requiring VA-ECMO. She was enterovirus positive, grew MRSA in respiratory cultures and was treated with prolonged antibiotics. CASE PRESENTATION:The patient spent 26 days on VA-ECMO followed by 61 days on VV-ECMO after failing decannulation due to refractory hypoxia. She developed anuric renal failure requiring CRRT during her second ECMO course.Following VV-ECMO decannulation, she required mechanical ventilation with high settings and had severe recurrent pulmonary hemorrhage requiring FFP, platelets and inhaled TXA. She had coronary dilation on CT imaging but was COVID-19 antibody negative. Serial echocardiograms demonstrated moderate LV dilation with normal systolic function. It was difficult to assess her diastolic function by echo, but with clinical concern for dysfunction she was started on milrinone.She underwent cardiac catheterization due to pulmonary bleeding and concerns for pulmonary hypertension. She had severely elevated biventricular filling pressures (RVEDp of 38 and LVEDp of 55) indicative of diastolic dysfunction. She had a high baseline cardiac index and normal PVR on milrinone and sildenafil. She also had significant AP collateral burden requiring coiling.Following this procedure her pulmonary hemorrhage resolved but her pulmonary mechanics did not improve. She continued to have multi-system organ failure with cardiac dysfunction, respiratory and renal failure. Her family did not wish to pursue organ transplantation and chose to redirect her care.DISCUSSION: This case is remarkable for several reasons. While large burns are known to produce an inflammatory response with cardiac dysfunction (1, 2), typically the degree of inflammation is proportional to the size of the burn and occurs early (3). This patient had a smaller TBSA burn that did not require surgery, yet she developed profound respiratory failure and shock requiring ECMO.During her hospitalization and 87 days on ECMO, the patient developed severe diastolic heart failure, AP collateral burden and coronary ectasia. This case demonstrates the utility of a diagnostic cardiac catheterization to evaluate for hemodynamic abnormalities after prolonged ECMO support, especially when echocardiogram is unrevealing. CONCLUSIONS:It is impossible to say whether these findings were a result of her prolonged ECMO runs, her burn physiologic state, or potentially a synergistic combination of the two. Additionally, while "long run" ECMO is becoming more common, little is known about the long-term cardiovascular effects of ECMO physiology. We report this case to encourage others to share cardiovascular complications after ECMO runs greater than 21 days.