LAUSR

Background A subjective clinical assessment of respiratory effort is made by observation of the respiratory rate, presence of indrawing of chest muscles and the work of breathing, and depends on the skill and experience of the observer. Structured Light Plethysmography (SLP) is a novel non-invasive light-based method that provides a detailed analysis of tidal breathing mechanics through chest movement analysis. We aimed to utilise SLP in children admitted due to acute wheezing and examine the relationship between tidal breathing and severity, and to track progression of their condition during hospitalisation. Methods Children from 1 month to 12 years old were screened upon admission to a high dependency unit due to acute wheezing in tertiary children´s hospital. SLP measurements were obtained during the first 24 hours from admission and repeated before discharge. Data on length of hospital stay and clinical severity score (mPIS) were compared to 3–5 min SLP measurements. Results Between 18th June to 16th July 2018 17 patients were screened, of which 11 were eligible and 4 were included (2 parental refusals, 5 outside screening window). Age range was 1.5–3.1 years. All four children had previous wheezing episodes and one had ongoing inhaled corticosteroid medication. Two were atopic and two had a history of chronic lung disease of prematurity (CLD). Length of hospital stay (LOS) varied between 33–45 hour; SLP measurements were obtained 7–17 hour (1st measurement) and 27–41 hour (2nd measurement) from admission. In tidal parameters only one child (table 1; patient 1) showed a clear obstructive pattern with tachypnoea, shortened Ti/Te and Ti/Tot-ratios, increased abdominal contribution and elevated IE50- flow ratio. However, elevated thoraco-abdominal asynchrony (TAA) was present in all children and TAA on average decreased between measurements (mean change from 56.8 to 27.9 degrees). Clinical severity score (mPIS) showed a similar trend (mean change 6.25 to 2.5), and 8 measurement pairs of TAA vs mPIS showed a crude positive correlation of R=0.54.Abstract P88 Table 1 Structured light plethysmography parameters and clinical outcomes in 4 children 1.5–3.1 years of age during acute admission for wheezing Conclusion SLP seems feasible in obtaining thoraco-abdominal movement analysis in clinical bedside setting. Thoraco-abdominal asynchrony may be a quantifiable measure of breathing distress in small children admitted due to acute wheezing.