The average number of index pulseless cardiac arrests occurring in hospitalized pediatric patients between 2008 and 2017 was estimated at 7,100 (95% prediction interval: 4,400, 9,900) cases per year. There was no clear change in incidences over time (incidence rate ratio: 0.97, 95%CI: 0.94, 1.00), p = 0.08). Numerical estimates are provided in Table S9.