The Science Journal of the American Association for Respiratory Care

2011 OPEN FORUM Abstracts

LARGE AIRWAY OBSTRUCTION IN A PATIENT WITH AN UNDIAGNOSED DOUBLE AORTIC ARCH.

Susan A. Roark, Esther Taylor, Sarah D. Keene; NICU, CHOA, Atlanta, GA

Introduction:Aortic arch anomalies account for only 30% of all congenital heart defects.Double aortic arch(DAA)is a relatively rare condition in which the aorta bifurcates into 2 vessels often resulting in a complete ring around the trachea(vascular ring).Varying degrees of airway compression can occur resulting in tracheomalacia and upper airway obstruction.Patients typically present with respiratory distress and stridor at birth but some may present later with a history of difficulty feeding and frequent respiratory infections.Definitive diagnosis is generally made by CT scan and repair of the defect is surgical.Here we present a patient(pt)with DAA and spirometry indicative of large airway obstruction with increased airway resistance. Case Summary:A 2 day old 37wk baby girl was admitted to our NICU for evaluation of stridor.She was noted to have respiratory distress,a high pitched cry,and stridor at the referring facility.An ECHO done prior to transfer was read to be WNL,as was a repeat ECHO done upon admission at our facility.She was initially managed on a HFNC,(High Flow Nasal Cannula)at 6LPM but progressed rapidly to NCPAP and then required intubation approximately 25hrs after admission due to increased WOB and ventilatory failure. The pts.flow-volume loops and pressure volume curves were indicative of a variable upper airway obstruction and her airway resistance was elevated at 263cmH2O/L/sec with a compliance of 7ml/cmH2O.Increasing the PEEP from 5cm to 10cm reduced the airway resistance to 108cmH2O/L/sec but there was minimal improvement in her spirometry.Further increase of the PEEP to 14cm produced near normal loops.Bronchoscopy demonstrated severe tracheomalacia with possible vascular compression of the airway.A CT scan confirmed the diagnosis of a DAA and she was subsequently taken to the OR for surgical repair.Post-operatively her flow-volume loops and pressure volume curves were dramatically improved and her airway resistance decreased to 70 cmH2O/L/sec.She was successfully extubated to room air 5 days after her repair and was discharged 8 days later. Conclusion:Higher than expected levels of PEEP may be needed in pts.with tracheomalacia.Ventilator spirometry can be valuable in pts.with large airway obstruction.While the definitive diagnosis of this pt.was made by CT scan,this case demonstrates the usefulness of flow volume loops, pressure volume curves,and airway resistance in detecting large airway obstruction in this patient.
Sponsored Research - None