Predictors of inadequate initial echocardiography in suspected Kawasaki disease: Criteria for sedation

Objective: Kawasaki disease is the primary cause of acquired pediatric heart disease in developed nations. Timely diagnosis of Kawasaki disease incorporates transthoracic echocardiography for visualization of the coronary arteries. Sedation improves this visualization, but not without risks and resource utilization. To identify potential sedation criteria for suspected Kawasaki disease, we analyzed factors associated with diagnostically inadequate initial transthoracic echocardiography performed without sedation. Design: This retrospective review of patients < 18 years old undergoing initial transthoracic echocardiography for the inpatient evaluation of suspected Kawasaki disease from 2009 to 2015 occurred at a medium-sized urban children's hospital. The primary outcome was diagnostically inadequate transthoracic echocardiography without sedation due to poor visualization of the coronary arteries, determined by review of clinical records. The associations of the primary outcome with demographics, Kawasaki disease type, laboratory data, fever, and antipyretic or intravenous immunoglobulin treatment prior to transthoracic echocardiography were analyzed. Results: In total, 112 patients (44% female, median age 2.1 years, median BSA 0.54 m²) underwent initial transthoracic echocardiography for suspected Kawasaki disease, and 99 were not sedated. Transthoracic echocardiography was diagnostically inadequate in 19 out of these 99 patients (19.2%) and was associated with age ≤ 2.0 years, weight ≤ 10.0 kg, and antipyretic use ≤ 6 hours before transthoracic echocardiography (all P <.05). These variables did not reach statistical significance on multivariable analysis. Conclusions: Patients ≤ 2.0 years or ≤ 10.0 kg or those recently receiving antipyretics, potentially a surrogate for irritability, were associated with diagnostically inadequate transthoracic echocardiography during the inpatient workup of Kawasaki disease. These factors should be considered when deciding which patients to sedate for initial Kawasaki disease transthoracic echocardiography.