岸原 悠貴

<h4>Aim</h4>Asphyxial out-of-hospital cardiac arrest (OHCA) is associated with poor outcomes and may have a narrower time window for favourable outcomes compared to cardiac-origin OHCA. However, studies examining cardiopulmonary resuscitation (CPR) duration in OHCA due to asphyxiation are limited. Hence, this study aimed to investigate the relationship between CPR duration and prognosis in patients who experienced OHCA due to asphyxiation.<h4>Methods</h4>This retrospective study used data from the Japanese Association for Acute Medicine's OHCA registry for June 2014 to December 2021. The study population comprised adult patients who received CPR by emergency medical service personnel and achieved return of spontaneous circulation. The primary outcome was one-month survival; the secondary outcome was favourable neurological outcome at one month (cerebral performance category 1 or 2). The influence of CPR duration was examined using logistic regression analysis after adjusting for multiple confounding factors.<h4>Results</h4>The analysis included 2,594 patients of asphyxiation-induced OHCA. The median CPR duration was 26 minutes (interquartile range, 17-35 minutes). At one month, 515 patients (19.9%) survived and 62 (2.4%) achieved favourable neurological outcomes. Increasing CPR duration was associated with lower chances of one-month survival and favorable neurological outcome (aOR per minute: 0.88 and 0.78, respectively; 95% CI: 0.86-0.90 and 0.71-0.85, respectively). The probability of favorable neurological outcome and survival dropped below 1% after 4 and 31 minutes of CPR, respectively.<h4>Conclusions</h4>Prolonged CPR was associated with poor outcomes in patients with asphyxiation-related OHCA and may be futile in these cases.

<h4>Background</h4>Out-of-hospital cardiac arrest (OHCA) has poor survival rates, but extracorporeal cardiopulmonary resuscitation (ECPR) shows promise for selected patients, as a second line of therapy after failure of conventional CPR to obtain return of spontaneous circulation, despite implementation challenges. This study aimed to identify distinct sub-phenotypes among patients with OHCA who undergo ECPR and to investigate their association with clinical outcomes.<h4>Methods</h4>This multi-center, retrospective, observational study used the Japanese Association for Acute Medicine OHCA registry from 83 hospitals that performed ECPR among 91 participating centers between June 2014 and December 2020. We included adult patients with OHCA who received ECPR during cardiac arrest. Three-class latent class analysis (LCA) was employed to identify sub-phenotypes based on 15 variables, including pre- and in-hospital factors. Logistic regression analysis was used to assess the association between sub-phenotypes and 30-day survival and neurological outcomes.<h4>Results</h4>A total of 1528 patients were included. The median low-flow time was 47 min (interquartile rage: 38-58 min). The 30-day survival rate for eligible patients was 20.9%. LCA identified three distinct sub-phenotypes: Standard ECPR Group (n = 702), Delayed ECPR Group (n = 457), and Non-shockable Rhythm Group (n = 369). The variables with high discriminative power in the LCA was low-flow time, followed by pre-hospital shock delivery and initial cardiac rhythm. Thirty-day survival rates varied significantly among the sub-phenotypes (p = 0.001): Standard ECPR Group (26.9%), Delayed ECPR Group (17.1%), and Non-shockable Rhythm Group (14.1%). Favorable neurological outcomes at 30 days also differed significantly (p = 0.004), with the Standard ECPR Group showing the highest rate (12.1%). After adjusting for covariates, both the Delayed ECPR Group (adjusted OR: 0.61, 95% CI 0.44-0.82) and Non-shockable Rhythm Group (adjusted OR: 0.47, 95% CI 0.32-0.68) had significantly lower odds of 30-day survival compared to the Standard ECPR Group.<h4>Conclusions</h4>Three clinically meaningful sub-phenotypes were identified using simple pre-hospital and in-hospital factors, with low-flow time emerging as the most critical discriminating factor. The sub-phenotypes showed significant associations with clinical outcomes and provide a practical framework for ECPR patient stratification. These findings suggest that timing optimization may be as important as rhythm characteristics for ECPR patient selection and support the development of sub-phenotype-specific treatment strategies.

Traumatic injury to the oculomotor nerve is a serious condition and generally carries a poor prognosis.Herein, we report a case of oculomotor nerve disruption with traumatic subarachnoid hemorrhage that was identified using an imaging technique. A 63-year-old female patient was brought to our emergency department following a traffic accident. Conservative treatment was initiated, leading to an improvement in her level of consciousness, although her right oculomotor nerve palsy symptoms remained unalleviated. She was discharged 2 weeks later with persistent symptoms of right oculomotor nerve palsy. In cases of cranial nerve palsy following head injuries, magnetic resonance imaging using steady-state constructive interference can provide valuable insights for detecting damage within the tentorial gap.

<h4>Objective</h4>To determine the association between timing of advanced airway management (AAM) and outcomes in witnessed pediatric out-of-hospital cardiac arrest (OHCA).<h4>Methods</h4>We performed a retrospective cohort study using data from the OHCA registry in Japan. We included pediatric patients (<18 y) with OHCA who received AAM. We compared patients who received AAM at 1 to 10, 11 to 20, and 21 to 30 minutes after emergency medicine service (EMS) contact with the patient with those who had not yet received AAM but remained eligible to receive it at those times, respectively. The primary and secondary outcome measurements were survival and favorable neurological outcome at 1 month, respectively. To address resuscitation time bias, we performed risk-set matching analyses using time-dependent propensity score.<h4>Results</h4>A total of 269 patients were included. The numbers receiving AAM in each time period were 60 in the 1 to 10 minute period, 83 in the 11 to 20 minute period, and 84 in the 21 to 30 minute period. The association between patients who received AAM in each time period and survival was compared with patients who had not yet received AAM but remained eligible to receive it in that time period: 1 to 10 minutes [risk ratio (RR): 2.12 (95% CI: 0.61-7.33)], 11 to 20 minutes [RR: 3.03 (95% CI: 1.13-8.12)], and 21 to 30 minutes [RR: 0.95 (95% CI: 0.46-1.96)]. The association with favorable neurological outcomes: 1 to 10 minutes [RR: 2.47 (95% CI: 0.42-14.56)], 11 to 20 minutes [RR: 2.54 (95% CI: 0.63-10.23)], 21 to 30 minutes [RR: 0.86 (95% CI: 0.25-2.99)].<h4>Conclusion</h4>In witnessed pediatric OHCA patients who went on to receive AAM, receiving this treatment in the time interval of 11 to 20 minutes was associated with survival, while earlier and later AAM times showed no association. Meanwhile, no association with favorable neurological outcomes was observed.