3.2 Severity data
Compared with the pool of previous seasons, in 2022-2023 the most reliable parameters of severity significantly increased, i.e. the rate of children receiving an urgent nursing triage code at ED presentation(p<0.001), the need for respiratory support (p=0.002 ), the median length of stay (5 vs 4,p=0.001 ), and the median duration of respiratory support (4 vs 3, p=0.016 ) (Figure 2 ).
Moreover, a significant increasing trend in high-flow nasal cannula (HFNC) use over the study years (rs = 0.943, p (2-tailed) = 0.017 ) was evident (Figure 2 ).
The increase in MV and HFNC use was also noticed considering only RSV bronchiolitis (Figure 4).