Clustering out-of-hospital cardiac arrest patients with non-shockable rhythm by machine learning latent class analysis.

Aim: We aimed to identify subphenotypes among patients with out-of-hospital cardiac arrest (OHCA) with initial non-shockable rhythm by applying machine learning latent class analysis and examining the associations between subphenotypes and neurological outcomes. Methods: This study was a retrospective analysis within a multi-institutional prospective observational cohort study of OHCA patients in Osaka, Japan (the CRITICAL study). The data of adult OHCA patients with medical causes and initial non-shockable rhythm presenting with OHCA between 2012 and 2016 were included in machine learning latent class analysis models, which identified subphenotypes, and patients who presented in 2017 were included in a dataset validating the subphenotypes. We investigated associations between subphenotypes and 30-day neurological outcomes. Results: Among the 12,594 patients in the CRITICAL study database, 4,849 were included in the dataset used to classify subphenotypes (median age: 75 years, 60.2% male), and 1,465 were included in the validation dataset (median age: 76 years, 59.0% male). Latent class analysis identified four subphenotypes. Odds ratios and 95% confidence intervals for a favorable 30-day neurological outcome among patients with these subphenotypes, using group 4 for comparison, were as follows; group 1, 0.01 (0.001-0.046); group 2, 0.097 (0.051-0.171); and group 3, 0.175 (0.073-0.358). Associations between subphenotypes and 30-day neurological outcomes were validated using the validation dataset. Conclusion: We identified four subphenotypes of OHCA patients with initial non-shockable rhythm. These patient subgroups presented with different characteristics associated with 30-day survival and neurological outcomes.

Two cases of cryptogenic life-threatening hemoptysis - identification and management of bleeding point.

Cases: Case 1: A 63-year-old woman was referred for coughing blood. Although cardiorespiratory dynamics were stabilized by artificial respiration under sedation, severely poor ventilation developed from asphyxia associated with massive respiratory tract hemorrhage. One-lung ventilation was temporarily secured by endotracheal tube insertion into the left main bronchus just prior to cardiopulmonary arrest.Case 2: A 72-year-old man was referred for massive hemoptysis after coughing, then intubated and placed on a respirator. During angiography, blood clots collected with bronchoscopy confirmed extravascular leakage into the right main bronchus. Outcomes: Both showed no hemoptysis recurrence after bronchial artery embolization and were discharged. Case 1 required intensive treatment for 6 days, including artificial respiratory management. Conclusion: Emergency one-lung ventilation was required for asphyxia in Case 1, and we had difficulties with bleeding point identification and hemostatic therapy. From that experience, we noted hemoptysis during angiography using bronchoscopy in Case 2, enabling prompt bronchial artery embolization.

Actual treatments for out-of-hospital ventricular fibrillation at critical care medical centers in Osaka: a pilot descriptive study.

AIM: Although advanced treatments are provided to improve outcomes after out-of-hospital ventricular fibrillation, including shock-resistant ventricular fibrillation, the actual treatments in clinical settings have been insufficiently investigated. The aim of the current study is to describe the actual treatments carried out for out-of-hospital ventricular fibrillation patients, including shock-resistant ventricular fibrillation patients, at critical care medical centers. METHODS: We registered consecutive adult patients suffering bystander-witnessed out-of-hospital cardiac arrest of cardiac origin, for whom resuscitation was attempted by emergency medical service personnel, who had ventricular fibrillation as an initial rhythm, and who were transported to critical care medical centers in Osaka from March 2008 to December 2008. This study merged data on treatments after transportation, collected from 11 critical care medical centers in Osaka with the prehospital Utstein-style database. RESULTS: During the study period, there were 260 bystander-witnessed ventricular fibrillation arrests of cardiac origin. Of them, 252 received defibrillations before hospital arrival, 112 (44.4%) were transported to critical care medical centers, and 35 had shock-resistant ventricular fibrillation. At the critical care medical centers, 54% (19/35), 40% (14/35), and 46% (16/35) of shock-resistant ventricular fibrillation patients were treated with extracorporeal life support, percutaneous coronary interventions, and therapeutic hypothermia, respectively, but their treatments differed among institutions. Some patients with prolonged arrest without prehospital return of spontaneous circulation who received advanced treatments had neurologically favorable survival, whereas approximately two-thirds of shock-resistant ventricular fibrillation patients with advanced treatments did not. CONCLUSION: This pilot descriptive study suggested that actual treatments for prehospital ventricular fibrillation patients differed between critical care medical centers. Further studies are warranted to evaluate the effectiveness of in-hospital advanced treatments for ventricular fibrillation including shock-resistant ventricular fibrillation.