Effectiveness of the Abdominal Thrust Maneuver for Airway Obstruction Removal: Analysis of Data from the National Emergency Medical Services Information System.

BACKGROUND: Foreign body airway obstruction (FBAO) is a life-threatening emergency. Abdominal thrusts are recommended as first aid, but the success rate for this technique is unclear. Using information from a large database of emergency medical services (EMS) data in the United States, we evaluated the success rate of abdominal thrusts and identified patient characteristics that were associated with the success of the technique. METHODS: A retrospective observational study was conducted using data from the National Emergency Medical Services Information System (NEMSIS) to ascertain the success of abdominal thrusts in patients with FBAO from nearly 14,000 EMS agencies. Success was defined by positive evaluations on subjective and objective EMS criteria. RESULTS: Analysis of 1,947 cases yielded a 46.6% success rate for abdominal thrusts in removing obstructions. The age distribution was bimodal, with peaks during infancy and old age. June had the highest incidence of FBAO. Incidents were most frequent during lunch and dinner times, and most cases occurred in private residences. The first-time success rate was 41.5%, and a lower level of impaired consciousness was associated with lower success rates. A lower incidence of cardiac arrest was noted in successful cases. The success rate was high (60.2%) for children (age ≤15 years), with differences in demographic characteristics and a lower rate of impaired consciousness and cardiac arrests, as compared with unsuccessful interventions in the same age group. CONCLUSIONS: Our study showed a 46.6% success rate for abdominal thrusts in patients with FBAO. The success group had a lower proportion of impaired consciousness and cardiopulmonary arrest than the failure group. Future studies should attempt to identify the most effective maneuvers for clearing airway obstruction.

Effect of Cardiopulmonary Resuscitation Training for Layperson Bystanders on Outcomes of Out-of-Hospital Cardiac Arrest: A Prospective Multicenter Observational Study.

BACKGROUND: Effective bystander cardiopulmonary resuscitation (CPR) improves outcomes in out-of-hospital cardiac arrest (OHCA) patients. However, the effect of CPR training on the rate of return of spontaneous circulation (ROSC) among laypersons has yet to be thoroughly evaluated. METHODS: This prospective, multicenter observational study was conducted across 42 centers in Japan. We assessed OHCA patients who received bystander CPR from a layperson, excluding those performed by healthcare staff. The primary outcome was the ROSC rate. Secondary outcomes included pre-hospital ROSC, ROSC after hospital arrival, favorable neurological outcomes, and 30-day survival. Propensity score with inverse probability treatment weighting (IPTW) was used to adjust for confounders, including age, sex, presence or absence of witnesses, and past medical history. RESULTS: A total of 969 OHCA patients were included, divided into CPR-trained (n=322) and control (n=647). Before adjustment, the ROSC rate was higher in the trained group than the control (40.1% vs. 30.1%, P < 0.01). After IPTW adjustment, the trained group showed a significantly higher ROSC rate (36.7% vs. 30.6%; P = 0.02). All secondary outcomes in the trained group were significantly improved before adjustment. After IPTW adjustment, the trained group showed improved rates of pre-hospital ROSC and ROSC after hospital arrival (30.7% vs. 24.0%; P < 0.01, 23.9% vs. 20.7%; P = 0.04). There were no differences in neurological outcomes and 30-day survival. CONCLUSION: This study demonstrated that CPR training for laypersons was associated with increased ROSC rates in OHCA patients, indicating potential advantages of CPR training for non-healthcare professionals.

Usefulness of Self-Selected Scenarios for Simple Triage and Rapid Treatment Method Using Virtual Reality.

BACKGROUND: Repeated triage training is necessary to maintain and improve the accuracy of simple triage and rapid treatment (START), a popular triage method. Virtual reality (VR) may be more effective than conventional training methods. This study aimed to verify the educational usefulness of START using VR originally developed for students. METHODS: A VR was initially developed with a function that allowed students to select the triage procedure and its evaluation. Triage was performed using a simple modified START method, and eight scenarios were developed. The participants included 70 paramedic students classified into VR and live lecture groups. They took a 20-question written test that evaluated their academic ability before the course. After the course, a practical test and a 20-question written test were conducted. The total score of the practical test was 43 points. Triage procedure (1 point), observation and evaluation (1-5 points), and triage categories (1 point) were evaluated in this test. RESULTS: The VR and live lecture groups consisted of 33 and 29 participants, respectively. No significant differences were observed pre- and post-test. In the practical test, the median (interquartile range) score was 29 (26-32) and 25 (23-29) for the VR and live lecture groups, respectively, with the VR group scoring significantly higher (P=0.03). CONCLUSION: Our results confirmed the educational usefulness of selective VR for active learning of START. Therefore, VR combined with live lectures and simulations would be an optimal educational technique.

Characteristics and Outcomes of Emergency Transferred Patients with Foreign Body Airway Obstruction in Tokyo, Japan.

INTRODUCTION: Foreign body airway obstruction (FBAO) is a life-threatening emergency, and the prognosis of patients with FBAO is greatly affected by the prehospital process. There are only a few large-scale studies analyzing prehospital process databases of the fire department. STUDY OBJECTIVE: The aim of this study was to investigate whether characteristics of patients with FBAO were associated with prehospital factors and outcomes. METHODS: In this retrospective observational study, patients transferred to the hospital by the Tokyo, Japan Fire Department for FBAO from 2017 through 2019 were included. The association between neurologically favorable survival among the characteristics of patients with FBAO and prehospital factors affecting the outcomes was evaluated. RESULTS: Of the 2,429,175 patients, 3,807 (0.2%) patients had FBAO. The highest number of FBAO cases was 99 (2.6%), which occurred on January 1 (New Year's Day), followed by 40 cases (1.1%) on January 2, and 28 cases (0.7%) on January 3. The number of patients who experienced out-of-hospital cardiac arrest (OHCA) caused by FBAO was 1,644 (43.2%). Comparing the OHCA and non-OHCA groups, there were significant differences in age, sex, time spent at the site, and distance between the site and hospital. Cardiac arrest was significantly lower in infants after FBAO (P < .001). In total, 98.2% of patients who did not have return of spontaneous circulation (ROSC) before hospital arrival died within 30 days, a significantly higher mortality rate than that in patients who had ROSC (98.2% versus 65.8%; P < .001). CONCLUSIONS: Among patients who did not have ROSC following FBAO upon arrival at the hospital, 98.2% died within 30 days. Thus, it is important to remove foreign bodies promptly and provide sufficient ventilation to the patient at the scene to increase the potential for ROSC. Further, more precautions should be exercised to prevent FBAO at the beginning of the year.

Development of a Machine Learning Model to Predict Cardiac Arrest during Transport of Trauma Patients.

BACKGROUND: Trauma is a serious medical and economic burden worldwide, and patients with traumatic injuries have a poor survival rate after cardiac arrest. The authors developed a prediction model specific to prehospital trauma care and used machine learning techniques to increase its accuracy. METHODS: This retrospective observational study analyzed data from patients with blunt trauma injuries due to traffic accidents and falls from January 1, 2018, to December 31, 2019. The data were collected from the National Emergency Medical Services Information System, which stores emergency medical service activity records nationwide in the United States. A random forest algorithm was used to develop a machine learning model. RESULTS: The prediction model had an area under the curve of 0.95 and a negative predictive value of 0.99. The feature importance of the predictive model was highest for the AVPU (Alert, Verbal, Pain, Unresponsive) scale, followed by oxygen saturation (SpO2). Among patients who were progressing to cardiac arrest, the cutoff value was 89% for SpO2 in nonalert patients. CONCLUSIONS: The machine learning model was highly accurate in identifying patients who did not develop cardiac arrest.

A Study on Points of Respiratory Assist Devices Using in Pre-Hospital Care Respiratory Assist Devices in Pre-Hospital Care.

BACKGROUND: In Japan, increasing the number of ambulance requests, the case with the use of respiratory assistance devices in prehospital care by paramedics is also increasing1. When patient experiences respiratory failure, the first responders frequently select a respiratory assist device (RAD) such as Bag Valve Mask (BVM), Jackson Rees (JR), or BVM with Gas Supply Valve® (BVM+GSV). This is based on both evaluation and experience as there is no study indicating which RAD is the best choice at the pre-hospital emergency site. This study clarified the precautions when using BVM, JR, and BVM+GSV in pre-hospital emergency medical care with healthy volunteers. METHODS: Twenty healthy adults were fitted with a RAD while breathing spontaneously, and changes in vital signs and ETCO2 were observed. RESULTS: The level of ETCO2 became elevated after each RAD was attached. The value was significantly higher in the JR group than in the others. CONCLUSIONS: The study showed that even in the presence of spontaneous breathing, ETCO2 increased markedly with the application of respiratory assist devices that are used in pre-hospital care for conditions such as hypoxemia and ventilatory disturbance. The increase in ETCO2 was particularly significant in the JR group, suggesting the need for caution when selecting JRs for pre-hospital care. As the number of subjects was only 20 for each RAD, studies with a larger sample size are needed.

Accuracy of breathing and radial pulse assessment by non-medical persons: an observational cross-sectional study.

Early recognition of cardiopulmonary arrest (CPA) expedites emergency calls and resuscitation and improves the survival rate of unresponsive individuals. However, the accuracy of breathing and radial artery pulse assessment by non-medical persons is poorly understood. The aim of this study was to determine the accuracy of breathing assessment and radial pulse palpation among 450 non-medical personnel using a high-fidelity simulator. We examined the accuracy of 10 second's assessment for breathing and radial pulse using a high-fidelity mannequin simulator, included 496 non-medical participants (school teachers) between 2016-2018. For a primary results, the sensitivity for the detection of the presence of the breathing and radial pulse was 96.2% (97.5% for sensitivity and 92.0% for specificity) and 91.7% (99.1% for sensitivity and 56.8% for specificity), respectively. Futher, breathing rate and radial pulse rate were strongly correlated with the assessments, with Spearman's correlation coefficients of 0.813 (P < 0.001) and 0.719 (P < 0.001), respectively. In contrast, radial pulse strength was weakly correlated with the assessment (coefficient of 0.288, P < 0.001). Our results suggested that non-medical persons would show high accuracy in detecting and measuring respiration and radial pulse, although they did not accurately determine radial pulse strength for the early recognition of CPA.

Do Video Calls Improve Dispatcher-Assisted First Aid for Infants with Foreign Body Airway Obstruction? A Randomized Controlled Trial/Simulation Study.

BACKGROUND: Because choking quickly leads to cardiopulmonary arrest, it is crucial that bystanders remove foreign bodies effectively. Although oral instructions in video calls by dispatchers have improved the quality of cardiopulmonary resuscitation, it is unclear whether video calls improve the quality of first aid for choking infants. Therefore, this simulation study aimed to determine whether video calls with dispatchers improve the quality of first aid for infants with foreign body airway obstruction (FBAO). METHODS: Seventy first-year college students randomly assigned in pairs to communicate by video or audio calls participated in simulated emergency calls for infants with FBAO. Both groups began with oral instruction in voice calls until the transition was made to video calls in the video group. The primary outcome was quality of first aid performance, which was categorized as excellent, acceptable, or poor on the basis of existing guidelines. RESULTS: There were 17 simulations in the video-call groups and 16 in the voice-call groups. After initial oral instruction, the proportion of rescuers that received an evaluation of excellent or acceptable did not differ significantly between the groups (video, 41% vs. voice, 50%; P=0.61); however, evaluations for seven rescuers improved after transitioning to video calls. Ultimately, the proportion receiving a poor evaluation was significantly lower in the video-call group than in the voice-call group (50% vs. 82%, P=0.049). CONCLUSION: Oral instruction communicated by video calls improved the quality of first aid for infants with FBAO.

Evaluation of outcomes after EMS-witnessed traumatic out-of-hospital cardiac arrest caused by traffic collisions.

AIM: The survival rate of patients with traumatic cardiac arrest is 3% or lower. Cardiac arrest witnessed by emergency medical services (EMS) accounts for approximately 16% of prehospital traumatic cardiac arrests, but the prognosis is unknown. We aimed to compare the 1-month survival rate of cardiac arrest witnessed by EMS with that of cardiac arrest witnessed by bystanders and unwitnessed cardiac arrest in traffic trauma victims; further, the time from injury to cardiac arrest was assessed. METHODS: This analysis used the Utstein Registry in Japan and included data of 3883 patients with traumatic cardiac arrest caused by traffic collisions registered between 2014 and 2019 in Japan. RESULTS: The 1-month survival rate was 10.9% in the EMS-witnessed cardiac arrest group; this was significantly higher than that in the bystander-witnessed (7.2%) and unwitnessed (5.6%) cardiac arrest groups (P < 0.01). The median time from injury to cardiac arrest was 18 min (25% quartile: 12, 75% quartile: 26). CONCLUSION: The 1-month survival rate was significantly higher in the EMS-witnessed cardiac arrest group than in the bystander-witnessed and unwitnessed cardiac arrest groups. It is important to prevent progression to cardiac arrest in trauma patients with intact respiratory function and pulse rate at the time of contact with EMS. A system for early recognition of severe trauma is needed, and a doctor's car or helicopter can be requested as needed. We believe that early recognition and prompt intervention will improve the prognosis of prehospital traumatic cardiac arrest.

Wearing a face mask during controlled-intensity exercise is not a risk factor for exertional heatstroke: A pilot study.

AIM: This study aimed to measure the influence of wearing face masks on individuals' physical status in a hot and humid environment. METHODS: Each participant experienced different physical situations: (i) not wearing a mask (control), (ii) wearing a surgical mask, (iii) wearing a sport mask. An ingestible capsule thermometer was used to measure internal core body temperature during different exercises (standing, walking, and running, each for 20 min) in an artificial weather room with the internal wet-bulb globe temperature set at 28°C. The change in the participants' physical status and urinary liver fatty acid-binding protein (L-FABP) were measured. RESULTS: Six healthy male volunteers were enrolled in the study. In each participant, significant changes were observed in the heart rate and internal core temperatures after increased exercise intensity; however, no significant differences were observed between these parameters and urinary L-FABP among the three intervention groups. CONCLUSION: Mask wearing is not a risk factor for heatstroke during increased exercise intensity.