537 - Diaphragmatic Ultrasound in Children With Asthma Exacerbations

Poster Number: 537
Publication Number: 537.242

Elaine Chiang, NewYork-Presbyterian Morgan Stanley Children's Hospital, New York, NY, United States; David Kessler, Columbia University Vagelos College of Physicians and Surgeons, Leonia, NJ, United States; Joni E. Rabiner, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States

Background: Asthma is a leading cause of pediatric emergency department (PED) visits, yet few tools exist to risk stratify children with asthma. Diaphragmatic ultrasound (DUS) is a novel method of assessing respiratory distress; however, data is lacking for children with asthma exacerbations.

Objective: Our primary aim was to determine if DUS, specifically diaphragmatic excursion (DE) or diaphragmatic thickening (DT), correlated with asthma severity as determined by the Pediatric Respiratory Assessment Measure (PRAM) score. Secondarily, we examined if DE or DT correlated with the need for respiratory support and evaluated interrater reliability.

Design/Methods: We conducted a prospective study of children 5-18 years presenting to a PED with an asthma exacerbation. DUS was performed by a trained pediatric emergency medicine sonologist in mid-axillary (DT) and subcostal views (DE and DT). The PRAM score was obtained at the time of the DUS. To evaluate interrater reliability, a subset of subjects had DUS performed by a second sonologist.

Results: We enrolled 47 unique subjects for a total of 51 encounters. The mean age was 9.1 ± 3.7 years and 37 (73%) were male. The mean time to obtain the DUS was 7.8 ± 4.4 minutes. 25 (49%) had mild, 24 (47%) had moderate, and 2 (4%) had severe asthma based on PRAM scores. PRAM scores were dichotomized into mild (0-4) and moderate (5-8) asthma and analyzed for associations with DUS measurements using independent t-tests. The 2 patients with severe asthma were excluded due to small sample size. There was a significant difference in midaxillary DT between children with mild and moderate asthma (p=0.02 95%CI -0.40 to -0.03); however, no difference was found in the subcostal view for DE or DT (p=0.78 95%CI -3.0 to 4.0 and p=0.29 95%CI -1.2 to 0.35, respectively). No association was found between the use of positive pressure in 5 patients and any of the DUS measures. 14/51 (27%) encounters had 2 sonologists perform DUS, with strong interrater reliability found for midaxillary DT (Pearson’s correlation 0.56) and poor association for subcostal DE and DT (Pearson’s correlation 0.18 and 0.23, respectively).Conclusion(s): DUS may be helpful in assessing severity of asthma exacerbations in children. Midaxillary DT showed correlation with asthma severity as well as strong interrater reliability. Future studies may benefit from focusing on the midaxillary view for DT to assess respiratory distress in children with asthma exacerbations.
Elaine Chiang Fellowship CV FINAL 8.14.21.pdf