Yoshio Tanaka’s research while affiliated with Kanazawa Medical University and other places

Objective: To identify the factors associated with a neurologically favourable survival of out-of-hospital cardiac arrest (OHCA) occurring in toilets. Methods: We retrospectively compared neurologically favourable 1-month survival rates and survival-related factors for 330,849 non-emergency medical service-witnessed OHCAs that occurred in toilets with those that occurred elsewhere using a nationwide database. Results: Compared to outpatient or hospital admission, OHCA was more likely to be associated with toilets (crude odds ratio [cOR] [95% confidence interval [CI]]: 2.52 [2.48–2.57]). The neurologically favourable 1-month survival rate for OHCA occurring in toilets (1.8%) was significantly lower than that in other places (2.9%) (cOR [95% CI]: 0.60 [0.53–0.68]). Bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use were minimal in toilets. Neither bystander CPR (adjusted OR [95% CI]: 1.19 [0.91–1.75]) nor AED use (adjusted OR [95% CI]: 2.05 [0.65–6.41]) was associated with improved neurologically favourable 1-month survival in toilets. Conclusions: Despite the poor neurologically favourable survival rate of OHCA in toilets, the provision of bystander CPR and AED was not associated with survival. Potential contributing factors include low rates of bystander intervention and delayed patient detection. To address this issue, focusing particular attention on unwell patients who use the toilets is crucial, and preventive approaches should be promoted.

Aim: To assess the impact of the 2020 coronavirus disease (COVID-19) pandemic on the prehospital characteristics and outcomes of out-of-hospital cardiac arrest (OHCA) in the elderly. Methods: In this population-based nationwide observational study in Japan, 563,100 emergency medical service-unwitnessed OHCAs in elderly (≥65 years) patients involving any prehospital resuscitation efforts were analysed (144,756, 140,741, 140,610, and 136,993 cases in 2020, 2019, 2018, and 2017, respectively). The epidemiology, characteristics, and outcomes associated with OHCAs in elderly patients were compared between 3 years pre-pandemic (2017-2019) and the pandemic year (2020). The primary outcome was neurologically favourable one-month survival. The secondary outcomes were the rate of bystander cardiopulmonary resuscitation (CPR), defibrillation by a bystander, dispatcher-assisted (DA)-CPR attempts, and one-month survival. Results: During the pandemic year, the rates of neurologically favourable 1-month survival (crude odds ratio, 95% confidence interval: 1.19, 1.14-1.25), bystander CPR (1.04, 1.03-1.06), and DA-CPR attempts (1.10, 1.08-1.11) increased, whereas the incidence of public access defibrillation (0.88, 0.83-0.93) decreased. Subgroup analyses based on interaction tests showed that the increased rate of neurologically favourable survival during the pandemic year was enhanced in OHCA at care facilities (1.51, 1.36-1.68) and diminished or abolished on state-of-emergency days (0.90, 0.74-1.09), in the mainly affected prefectures (1.08, 1.01-1.15), and in cases with shockable initial rhythms (1.03, 0.96-1.12). Conclusions: The COVID-19 pandemic increased the bystander CPR rate in association with enhanced DA-CPR attempts and improved the outcomes of elderly patients with OHCAs.

Aim Using the data from the All‐Japan Utstein Registry, this study evaluates the neurologically favourable patient outcomes and associated factors of out‐of‐hospital cardiac arrest (OHCA) with Japanese schoolchildren as witnesses. Methods We analysed 1,068 school‐age children (6–18 years old) who underwent OHCA from 2011 to 2016. Among the 1,068 cases, 179 were witnessed by schoolchildren and 889 were witnessed by other bystanders. Propensity score‐matched and logistic regression analyses were used to evaluate the outcomes and associated factors. Results The crude neurologically favourable outcome in the schoolchildren‐witnessed group was considerably higher than that in the other‐bystander‐witnessed group (19.6% versus 12.3%; P < 0.010). However, the difference was not significant in the propensity score‐matched analysis (19.6% versus 21.8%; P = 0.602). The multivariable logistic regression analyses of school‐age OHCA with schoolchildren as witnesses demonstrated that bystander cardiopulmonary resuscitation (CPR) provision (odds ratio [OR] 4.12, 95% confidence interval [CI] 1.44–11.75), shockable initial rhythm (OR 3.39, 95% CI 1.43–8.04), and defibrillation (OR 4.58, 95% CI 1.65–12.71) provided by any bystander were positively associated with favourable outcomes. By contrast, dispatcher‐assisted CPR provision (OR 0.28, 95% CI 0.11–0.70), exogenous cause (OR 0.16, 95% CI 0.03–0.86), adrenaline administration (0.25; 95% CI 0.07–0.92), and prolonged response time (OR 0.86; 95% CI 0.75–0.98) were negatively associated with favourable outcomes. Conclusions Patient outcomes did not differ significantly between schoolchildren‐ and other‐bystander‐witnessed cases of school‐age OHCA. Although schoolchildren as witnesses might not be inferior to other bystanders in school‐age OHCA, further studies are needed to examine the effect of bystander CPR by schoolchildren and basic life support education in schools.

Objective: To investigate the impact of epinephrine on prehospital rearrest and re-attainment of prehospital return of spontaneous circulation (ROSC). Methods: Data for 9,292 (≥ 8 years) out-of-hospital cardiac arrest (OHCA) patients transported to hospitals by emergency medical services were collected in Ishikawa Prefecture, Japan during 2010–2018. Univariate and multivariable analyses were retrospectively performed for 1,163 patients with prehospital ROSC. Results: Of 1,163 patients, rearrest occurred in 272 (23.4%) but not in 891 (76.6%). Both single and multiple doses of epinephrine administered before prehospital ROSC (adjusted odds ratio (OR): 3.62, 95% confidence interval (CI): 2.42–5.46 for 1 mg, and 4.27, 2.58–6.79 for ≥2 mg) were main factors associated with rearrest. The association between initial and rearrest rhythms was significantly associated with epinephrine administration (p = 0.02). However, the rearrest rhythm was primarily associated with the initial rhythm (p < 0.01). The majority of patients with the non-shockable initial rhythm had pulseless electrical activity (PEA) as the rearrest rhythm, regardless of epinephrine administration (80.4% for administration, 81.6% for no administration). When the initial rhythm was shockable, the primary rearrest rhythms in patients with and without epinephrine administration before prehospital ROSC were PEA (52.2%) and ventricular fibrillation/pulseless ventricular tachycardia (56.8%), respectively. Only epinephrine administration after rearrest was associated with prehospital re-attainment of ROSC (adjusted OR: 2.49, 95% CI: 1.20–5.19). Stepwise multivariable logistic regression analyses revealed that neurologically favorable outcome was poorer in patients with rearrest than those without rearrest (9.9% vs. 25.0%, adjusted OR: 0.42, 95% CI: 0.23–0.73). The total prehospital doses of epinephrine were associated with poorer neurological outcome in a dose-dependent manner (adjusted OR: 0.22, 95% CI: 0.13–0.36 for 1 mg; 0.09, 0.04–0.19 for 2 mg; 0.03, 0.01–0.09 for ≥3 mg, no epinephrine as a reference). Transportation to hospitals with a unit for post-resuscitation care was associated with better neurological outcome (adjusted OR: 1.53, 95% CI: 1.02–2.32). Conclusions: The requirement for epinephrine administration before prehospital ROSC was associated with subsequent rearrest. Routine epinephrine administrations and rearrest were associated with poorer neurological outcome of OHCA patients with prehospital ROSC.

Objective To investigate the association of school hours with outcomes of schoolchildren with out-of-hospital cardiac arrest (OHCA). Methods From the 2005–2014 nationwide databases, we extracted the data for 1660 schoolchildren (6–17 years) with bystander-witnessed OHCA. Univariate analyses followed by propensity-matching procedures and stepwise logistic regression analyses were applied. School hours were defined as 08:00 to 18:00. Results The neurologically favourable 1-month survival rate during school hours was better than that during non-school hours only on school days: 18.4% and 10.5%, respectively. During school hours on school days, patients with OHCA more frequently received bystander cardiopulmonary resuscitation (CPR) and public access defibrillation (PAD), and had a shockable initial rhythm and presumed cardiac aetiology. The neurologically favourable 1-month survival rate did not significantly differ between school hours on school days and all other times of day after propensity score matching: 16.4% vs 16.1% (unadjusted OR 1.02; 95% CI 0.69 to 1.51). Stepwise logistic regression analysis during school hours on school days revealed that shockable initial rhythm (adjusted OR 2.44; 95% CI 1.12 to 5.42), PAD (adjusted OR 3.32; 95% CI 1.23 to 9.10), non-exogenous causes (adjusted OR 5.88; 95% CI 1.85 to 20.0) and a shorter emergency medical service (EMS) response time (adjusted OR 1.15; 95% CI 1.02 to 1.32) and witness-to-first CPR interval (adjusted OR 1.08; 95% CI 1.01 to 1.15) were major factors associated with an improved neurologically favourable 1-month survival rate. Conclusions School hours are not an independent factor associated with improved outcomes of OHCA in schoolchildren. The time delays in CPR and EMS arrival were independently associated with poor outcomes during school hours on school days.