An uncommon case of hypoxia in a pediatric patient

ABSTRACT

INTRODUCTION: Pulmonary arteriovenous malformations (PAVM) are typically associated with hereditary hemorrhagic telangiectasia. Isolated PAVM are uncommon and usually present between the 4th-6th decades of life;they are rarely seen in children and infrequently necessitate ICU admission. DESCRIPTION A healthy 3-year-old boy presented to his pediatrician with a 3 day history of fever and rhinorrhea. He was hypoxic (SpO2=85%), so was placed on oxygen and transferred to an outside ED where he was found to have (non-COVID) coronavirus. He was admitted for supportive care but clinically deteriorated over the next 24 hours requiring intubation, ventilatory support with 100% FiO2, and inhaled nitric oxide. Despite these interventions he remained hypoxic. Echocardiogram demonstrated a structurally normal heart. Computed tomography angiogram showed multiple large peripheral PAVM in the left lower and upper lobes and no differentiation between arterial and venous phases indicating pulmonary shunting. He was transferred to our quaternary ICU for intervention. He underwent embolization of ~70% of his PAVM (limited due to contrast load). He initially improved, but 2 days post-intervention he declined with worsening hypoxia likely secondary to pulmonary vascular remodeling following intervention and residual shunt burden within the left lung. Given his instability, as well as an oxygenation index of 34, he was cannulated for venoarterial extracorporeal membrane oxygenation (ECMO). Following cannulation, his remaining PAVM were embolized. ECMO support was subsequently weaned and he was decannulated after 4 days. His ventilator support was weaned, and he was transferred back to the referring hospital on minimal settings. He was extubated the next day and quickly weaned to room air. He was discharged after 2.5 weeks and was doing well (SpO2=95%) at his pediatrician follow-up. DISCUSSION: This is the first case of a previously healthy child requiring cannulation for ECMO due to PAVM. This case is unique among patients with PAVM due to the early presentation, likely related to an acute respiratory illness disturbing previously well-compensated ventilation-perfusion mismatch. As highlighted in this case, ECMO can be used to support patients who require interventions for PAVM and during the transition to a new physiologic state.