BACKGROUND: A comprehensive understanding of the epidemiology of pediatric out-of-hospital cardiac arrest (OHCA) occurring under school supervision is lacking. We aimed to comprehensively describe the characteristics and outcomes of OHCA among students in elementary schools, junior high schools, high schools, and technical colleges in Japan. METHODS: OHCA data from 2008-2021 were obtained from the SPIRITS study, which provides a nationwide database of OHCAs occurring under school supervision across Japan. We included cases in which resuscitation was attempted by emergency medical service personnel or bystanders. The cases were classified into three groups based on their etiology: cardiac, non-cardiac, and traumatic origin. The primary outcome was one-month survival with favorable neurological outcomes, defined as a Glasgow-Pittsburgh cerebral performance category of 1 or 2. The demographic characteristics, event details, and outcomes were compared across the three groups by using χ² tests for categorical variables and one-way analyses of variance for continuous variables. RESULTS: During the 14-year study period, 602 OHCA cases were confirmed, with 430 (71.4%) classified as cardiac, 91 (15.1%) as non-cardiac, and 81 (13.5%) as traumatic origin. Non-cardiac and traumatic cases were less likely to be witnessed at the time of arrest (46.2% and 42.0%, respectively) than cardiac cases (82.6%; p < 0.001). Initiation of cardiopulmonary resuscitation by bystanders was less common in non-cardiac and traumatic cases (62.6% and 42.0%, respectively) than that in cardiac cases (82.8%; p < 0.001). The delivery of defibrillation using public-access automated external defibrillators was also significantly less frequent in non-cardiac (3.3%) and traumatic cases (6.2%) than that in cardiac cases (59.8%; p < 0.001). Ventricular fibrillation (VF) as the first documented rhythm was observed in 77.9% of cardiac cases but was much less common in non-cardiac (5.5%) and traumatic cases (8.6%; p < 0.001). One-month survival with favorable neurological outcomes was significantly lower in non-cardiac (6.6%) and traumatic cases (0%) than that in cardiac cases (50.2%; p < 0.001). CONCLUSIONS OHCAs of cardiac origin were more frequently associated with VF and had relatively good prognoses. In contrast, OHCAs of non-cardiac and traumatic origins consistently resulted in poor outcomes, highlighting the critical importance of prevention strategies to reduce the occurrence of these incidents.
Out-of-Hospital Cardiac Arrest/etiology* ; Humans ; Japan/epidemiology* ; Male ; Female ; Child ; Students/statistics & numerical data* ; Schools/statistics & numerical data* ; Adolescent ; Cardiopulmonary Resuscitation/statistics & numerical data* ; Emergency Medical Services/statistics & numerical data* ; Epidemiologic Studies

OBJECTIVES: Cholesteatoma is a nonneoplastic destructive lesion of the temporal bone with debated pathogenesis and bone resorptive mechanism. Both molecular and cellular events chiefly master its activity. Continued research is necessary to clarify factors related to its aggressiveness. We aimed to investigate the expression of Ki-67, cytokeratin 13 (CK13) and cytokeratin 17 (CK17) in acquired nonrecurrent human cholesteatoma and correlate them with its bone destructive capacity. METHODS: A prospective quantitative immunohistochemical study was carried out using fresh acquired cholesteatoma tissues (n=19), collected during cholesteatoma surgery. Deep meatal skin tissues from the same patients were used as control (n=8). Cholesteatoma patients were divided into 2 groups and compared (invasive and noninvasive) according to a grading score for bone resorption based upon clinical, radiologic and intraoperative findings. To our knowledge, the role of CK17 in cholesteatoma aggressiveness was first investigated in this paper. RESULTS: Both Ki-67 and CK17 were significantly overexpressed in cholesteatoma than control tissues (P < 0.001 for both Ki-67 and CK17). In addition, Ki-67 and CK17 were significantly higher in the invasive group than noninvasive group of cholesteatoma (P=0.029, P=0.033, respectively). Furthermore, Ki-67 and CK17 showed a moderate positive correlation with bone erosion scores (r=0.547, P=0.015 and r=0.588, P=0.008, respectively). In terms of CK13, no significant difference was found between cholesteatoma and skin (P=0.766). CONCLUSION: Both Ki-67 and CK17 were overexpressed in cholesteatoma tissue and positively correlated with bone resorption activity. The concept that Ki-67 can be a predictor for aggressiveness of cholesteatoma was supported. In addition, this is the first study demonstrating CK17 as a favoring marker in the aggressiveness of acquired cholesteatoma.
Bone Resorption ; Cholesteatoma* ; Ear, Middle ; Humans* ; Keratin-13* ; Keratin-17* ; Keratins* ; Ki-67 Antigen ; Prospective Studies ; Skin ; Temporal Bone