Lower limb muscle matters in patients with hypoxic brain injury following out-of-hospital cardiac arrest.

BACKGROUND: There are conflicting results regarding the association between body mass index and the prognosis of cardiac arrest patients. We investigated the association of the composition and distribution of muscle and fat with neurologic outcomes at hospital discharge in successfully resuscitated out-of-hospital cardiac arrest (OHCA) patients. METHODS: This prospective, single-centre, observational study involved adult OHCA patients, conducted between April 2019 and June 2021. The ratio of total skeletal muscle, upper limb muscle, lower limb muscle, and total fat to body weight was measured using InBody S10, a bioimpedance analyser, after achieving the return of spontaneous circulation. Restricted cubic spline curves with four knots were used to examine the relationship between total skeletal muscle, upper limb muscle, and lower limb muscle relative to total body weight and neurologic outcome at discharge. Multivariable logistic regression analysis was performed to assess an independent association. RESULTS: A total of 66 patients were enrolled in the study. The proportion of total muscle and lower limb muscle positively correlated with the possibility of having a good neurologic outcome. The proportion of lower limb muscle showed an independent association in the multivariable analysis (adjusted odds ratio, 2.29; 95% confidence interval, 1.06-13.98), and its optimal cut-off value calculated through receiver operating characteristic curve analysis was 23.1%, which can predict a good neurological outcome. CONCLUSIONS: A higher proportion of lower limb muscle to body weight was independently associated with the probability of having a good neurologic outcome in OHCA patients.

Development of an Extended Reality Simulator for Basic Life Support Training.

OBJECTIVE: Extended Reality (XR) is a simultaneous combination of the virtual and real world. This paper presents the details of the framework and development methods for an XR basic life support (XR-BLS) simulator, as well as the results of an expert usability survey. METHODS: The XR-BLS simulator was created by employing a half-torso manikin in a virtual reality environment and using BLS education data that is in line with the 2020 American Heart Association guidelines. A head-mounted display (HMD) and hand-tracking device were used to perform chest compressions and ventilation and to enable the use of an automated external defibrillator in a virtual environment. A usability study of the XR-BLS simulator through an expert survey was also conducted. The survey consisted of a total of 8 items: 3, 2, and 2 questions about the ease of use of XR-BLS, delivery of training, and artificial intelligence (AI) instructor in the simulator, respectively. RESULTS: The XR simulator was developed, and the expert survey showed that it was easy to use, the BLS training was well delivered, and the interaction with the AI instructor was clear and understandable. DISCUSSION/CONCLUSION: The XR-BLS simulator is useful as it can conduct BLS education without requiring instructors and trainees to gather.

Resuscitative endovascular occlusion of the aorta (REBOA) as a mechanical method for increasing the coronary perfusion pressure in non-traumatic out-of-hospital cardiac arrest patients.

AIM OF THE STUDY: Resuscitative endovascular balloon occlusion of the aorta (REBOA), originally designed to block blood flow to the distal part of the aorta by placing a balloon in trauma patients, has recently been shown to increase coronary perfusion in cardiac arrest patients. This study evaluated the effect of REBOA on aortic pressure and coronary perfusion pressure (CPP) in non-traumatic out of-hospital cardiac arrest (OHCA) patients. METHODS: Adult OHCA patients with cerebral performance category 1 or 2 prior to cardiac arrest, and without evidence of aortic disease, were enrolled from January to December 2021. Aortic pressure and right atrial pressure were measured before and after balloon occlusion. The CPP was calculated using the measured aortic and right atrial pressures, and the values before and after the balloon occlusion were compared. RESULTS: Fifteen non-traumatic OHCA patients were enrolled in the study. The median call to balloon time was 46.0 (IQR, 38.0-54.5) min. The median CPP before and after balloon occlusion was 13.5 (IQR, 5.8-25.0) and 25.2 (IQR, 12.0-44.6) mmHg, respectively (P = 0.001). The median increase in the estimated CPP after balloon occlusion was 86.7%. CONCLUSIONS: The results of this study suggest that REBOA may increase the CPP during cardiopulmonary resuscitation in patients with non-traumatic OHCA. Additional studies are needed to investigate the effect on clinical outcomes.

Comparison of extended reality and conventional methods of basic life support training: protocol for a multinational, pragmatic, noninferiority, randomised clinical trial (XR BLS trial).

BACKGROUND: Conventional cardiopulmonary resuscitation (CPR) training for the general public involves the use of a manikin and a training video, which has limitations related to a lack of realism and immersion. To overcome these limitations, virtual reality and extended reality technologies are being used in the field of medical education. The aim of this study is to explore the efficacy and safety of extended reality (XR)-based basic life support (BLS) training. METHODS: This study is a prospective, multinational, multicentre, randomised controlled study. Four institutions in 4 countries will participate in the study. A total of 154 participants will be randomly assigned to either the XR group or the conventional group stratified by institution and sex (1:1 ratio). Each participant who is allocated to either group will be sent to a separate room to receive training with an XR BLS module or conventional CPR training video. All participants will perform a test on a CPR manikin after the training. The primary outcome will be mean compression depth. The secondary outcome will be overall BLS performance, including compression rate, correct hand position, compression, and full release and hands-off time. DISCUSSION: Using virtual reality (VR) to establish a virtual educational environment can give trainees a sense of realism. In the XR environment, which combines the virtual world with the real world, trainees can more effectively learn various skills. This trial will provide evidence of the usefulness of XR in CPR education. TRIAL REGISTRATION: ClinicalTrials.gov NCT04736888. Registered on 29 January 2021.