Objective:To explore the clinical characteristics and prognostic risk factors of accidental injuries in pediatric intensive care unit(PICU).Methods:The children with accidental injuries admitted to the PICU at Shanghai Children′s Hospital from January 2017 to December 2019 were analyzed retrospectively.The patients were divided into survival group and death group according to outcome.We collected the patients′ clinical data and laboratory indexes, and analyzed the differences between two groups.Multivariate Logistic regression was used to screen the risk factors of death and receiver-operating characteristic(ROC)curve was used to determine the threshold.Results:(1)A total of 253 children were included, accounting for 5.2% of PICU hospitalization during the same period.There were 137 males(54.2%)and 116 females(45.8%), with an average age of 45(19, 96)months.The top three causes of accidental injuries were fall injury in 82 cases(32.4%), traffic accident in 70 cases(27.7%)and foreign body in 39 cases(15.4%). There were 22 cases of deaths, with a fatality rate of 8.7%.(2)The mean arterial pressure at admission in the death group was lower than that in the survival group( P<0.05), and the total length of stay was longer( P<0.001). There were significant differences in Glasgow coma scale, Pediatric Risk of Mortality Scoring Ⅲ(PRISM Ⅲ)between the two groups( P<0.001). In the death group, and the blood lactic acid(LA) significantly increased( P<0.001), hemoglobin and fibrinogen were lower than those in the survival group, the activated partial thromboplastin time and prothrombin time(PT)were significantly prolonged( P<0.001). (3)Multivariate Logistic regression analysis showed that PRISM Ⅲ score, LA and PT were independent risk factors for the death of accidental injuries.The area under curve(AUC)of PRISM Ⅲ score was 0.987(95% CI 0.976-0.999, P<0.001)and the cut-off value was 11 with a sensitivity of 100% and a specificity of 95.7%.The AUC of LA was 0.886(95% CI 0.810-0.961, P<0.001)and the cut-off value was 3.1 mmol/L with a sensitivity of 85.7% and a specificity of 77.3%.The AUC of PT was 0.835(95% CI 0.730-0.941, P<0.001)and the cut-off value was 13.9 s with a sensitivity of 86.6% and a specificity of 72.7%. Conclusion:The main accidental injuries in PICU of our hospital in the past three years are falling injuries, traffic accidents and foreign body injuries.PRISM Ⅲ score, LA and PT at admission are independent risk factors for predicting death.