PURPOSE: Trending the pediatric-adjusted shock index (SIPA) after admission has been described for children suffering severe blunt injuries (i.e. injury severity score (ISS)>15). We propose that following SIPA in children with moderate blunt injuries, as defined by ISS 10-14, has similar utility. METHODS: The trauma registry at a single institution was queried over a seven year period. Patients were included if they were between 4-16 years old at the time of admission, sustained a blunt injury with an ISS 10-14, and were admitted less than 12 hours after their injury (n=501). Each patient's SIPA was then calculated at 0, 12, 24, 36, and 48 hours (h) after admission and then categorized as elevated or normal at each time frame based upon previously reported values. Trends in outcome variables as a function of time from admission for patients with an abnormal SIPA to normalize as well as patients with a normal admission SIPA to abnormal were analyzed. RESULTS: In patients with a normal SIPA at arrival, elevation within the first 24h of admission correlated with increased length of stay (LOS). Increased transfusion requirement, incidence of infectious complications, and need for in-patient rehabilitation were also seen in analyzed subgroups. An elevated SIPA at arrival with increased length of time to normalize SIPA correlated with increased length of stay LOS in the entire cohort and in those without head injury, but not in patients with a head injury. No deaths occurred within the study cohort. CONCLUSIONS: Patients with an ISS 10-14 and a normal SIPA at time of arrival who then have an elevated SIPA in the first 24h of admission are at increased risk for morbidity including longer LOS and infectious complications. Similarly, time to normalize an elevated admission SIPA appears to directly correlate with LOS in patients without head injuries. No correlations with markers for morbidity could be identified in patients with a head injury and an elevated SIPA at arrival. This may be due to small sample size, as there were no relations to severity of head injury as measured by Head Abbreviated Injury Scale (Head AIS) and the outcome variables reported. This is an area of ongoing analysis. This study extends the previously reported utility of following SIPA after admission into milder blunt injuries