Rapid Response System and Limitations of Medical Treatment Among Children With Clinical Deterioration in Japan: A Multicenter Retrospective Cohort Study.

We investigated the role of rapid response systems (RRSs) in limitations of medical treatment (LOMT) planning among children, their families, and health care providers. This multicenter retrospective cohort study examined children with clinical deterioration using the Japanese RRS registry between 2012 and 2021. Children ( = 348) at 28 hospitals in Japan who required RRS calls were analyzed. Eleven (3%) of the 348 patients had LOMT before RRS calls and 11 (3%) had newly implemented LOMT after RRS calls. Patients with LOMT were significantly less likely to be admitted to an intensive care unit compared with those without (36% vs. 61%,  < 0.001) and were more likely to die within 30 days (45% vs. 11%,  < 0.001). LOMT issues existed in 6% of children who received RRS calls. RRS calls for clinically deteriorating children with LOMT were associated with less intensive care and higher mortality.