1: ULTRASOUND SCREENING FOR VOCAL CORD DYSFUNCTION AFTER CONGENITAL HEART SURGERY IN CHILDREN

Abstract

Introduction: Vocal cord dysfunction (VCD) is a common complication following congenital cardiac surgery. VCD is more frequently diagnosed in aortic arch repairs due to the risk of recurrent laryngeal nerve injury. We previously identified VCD as a key variable in feeding dysfunction leading to increased resource utilization in children with congenital heart surgery. The current diagnostic to identify VCD is Fiberoptic Endoscopy (FOE), however, Vocal Cord Ultrasound (VCUS) has been described as a screening tool to identify VCD in high-risk populations. We describe the performance of VCUS versus FOE in children following congenital cardiac surgery. Methods: Patients undergoing surgeries known to be associated with VCD were prospectively included. Patients underwent evaluation with FOE per our institutional protocol once they were weaned off of positive pressure ventilation. In addition to the FOE, four operators performed a bedside VCUS on high-risk patients. The results of the VCUS were compared against FOE for both diagnostic yield and patient tolerance. Patient tolerance was defined as changes in vital signs (i.e. bradycardia defined as heart rate < 100bpm, hypoxia defined as SpO2 decrease >10%, hypotension defined as fall in blood pressure by >10 mmHg, and respiratory distress defined as rate increase by 10. Results: Over two months, we screened 13 patients, of which 12 patients received FOE and VCUS. Eight patients (61%) were diagnosed with VCD by FOE. Qualitative interpretation of VCUS, with performers blinded to FOE results, had 100% sensitivity and specificity vs. FOE. VCUS had a lower incidence of respiratory distress (1 vs. 5, p=0.03) and hypoxia (0 vs. 2, p=0.06). No patients had bradycardia or hypotension. Conclusions: Preliminary data indicates that VCUS is very specific and sensitive in screening for VCD. In addition, VCUS was well tolerated by patients with a low incidence of complications. Further investigation is necessary to determine if VCUS can replace FOE as a screening tool for VCD in children following congenital cardiac surgery. Implementation of VCUS as the primary screening tool may prove important in resource-limited centers.