Incidence and factor analysis for the heat-related illness on the Tokyo 2020 Olympic and Paralympic Games.

Introduction: Among the 43 venues of Tokyo 2020 Olympic Games (OG) and 33 venues of Paralympic Games (PG) were held, the heat island effect was highly expected to cause heat-related illnesses in the outdoor venues with maximum temperatures exceeding 35°C. However, the actual number of heat-related illness cases during the competition was lower than that was initially expected, and it was unclear under what conditions or environment-related heat illnesses occurred among athletes. Object: To clarify the cause and factors contributing to the occurrence of heat-related illness among athletes participating in the Tokyo 2020 Olympic and Paralympic Games. Method: This retrospective descriptive study included 15 820 athletes from 206 countries. From 21 July 2021 to 8 August 2021 for the Olympics, and from 24 August 2021 to 5 September 2021 for the Paralympics. The number of heat-related illness cases at each venue, the incidence rate for each event, gender, home continent, as well as the type of competition, environmental factors (such as venue, time, location and wet-bulb globe temperature (WBGT)), treatment factor and the type of competition were analysed. Results: More number of heat-related illnesses among athletes occurred at the OG (n=110, 76.3%) than at the PG (n=36, 23.7%). A total of 100 cases (100%) at the OG and 31 cases (86.1%) at the PG occurred at the outdoors venues. In the OG, a total of 50 cases (57.9%) occurred during the competition of marathon running and race walking at Sapporo Odori Park. Six of those, were diagnosed with exertional heat illness and treated with cold water immersion (CWI) at OG and one case at PG. Another 20 cases occurred in athletics (track and field) competitions at Tokyo National Olympic Stadium. In total, 10 cases (10.0%) were diagnosed with severe heat illness in the OG and 3 cases (8.3%) in the PG. Ten cases were transferred to outside medical facilities for further treatment, but no case has been hospitalised due to severe condition. In the factor analysis, venue zone, outdoor game, high WBGT (<28°C) and endurance sports have been found to have a higher risk of moderate and severe heat-related illness (p<0.05). The incidence rate and severity could be attenuated by proper heat-related illness treatment (CWI, ice towel, cold IV transfusion and oral hydration) reduced the severity of the illness, providing summer hot environment sports. Conclusion: The Tokyo 2020 Olympic and Paralympic summer games were held. Contrary to expectations, we calculated that about 1 in 100 Olympic athletes suffered heat-related illness. We believe this was due to the risk reduction of heat-related illness, such as adequate prevention and proper treatment. Our experience in avoiding heat-related illness will provide valuable data for future Olympic summer Games.

Acute in-competition medical care at the Tokyo 2020 Olympics: a retrospective analysis.

OBJECTIVE: To analyse injuries and illnesses during the 2020 Tokyo Olympic Summer Games. METHODS: This retrospective descriptive study included 11 420 athletes from 206 National Olympic Committees and 312 883 non-athletes. Incidences of injuries and illnesses during the competition period from 21 July to 8 August 2021 were analysed. RESULTS: A total of 567 athletes (416 injuries, 51 non-heat-related illnesses and 100 heat-related illnesses) and 541 non-athletes (255 injuries, 161 non-heat-related illnesses and 125 heat-related illnesses) were treated at the competition venue clinic. Patient presentation and hospital transportation rates per 1000 athletes were 50 and 5.8, respectively. Marathons and race walking had the highest incidence of injury and illness overall (17.9%; n=66). The highest incidence of injury (per participant) was noted in boxing (13.8%; n=40), sport climbing (12.5%; n=5) and skateboarding (11.3%; n=9), excluding golf, with the highest incidence of minor injuries. Fewer infectious illnesses than previous Summer Olympics were reported among the participants. Of the 100 heat-related illnesses in athletes, 50 occurred in the marathon and race walking events. Only six individuals were transported to a hospital due to heat-related illness, and none required hospital admission. CONCLUSION: Injuries and heat-related illnesses were lower than expected at the 2020 Tokyo Olympic Summer Games. No catastrophic events occurred. Appropriate preparation including illness prevention protocols, and treatment and transport decisions at each venue by participating medical personnel may have contributed to these positive results.

Muscles used for chest compression under static and transportation conditions.

BACKGROUND: Unstable conditions during ambulance transportation are not conducive to the performance of high-quality cardiopulmonary resuscitation by emergency medical technicians. OBJECTIVE: The present study was conducted to clarify differences in the quality of chest compression and associated muscle activity between static and ambulance transportation conditions. METHODS: Nine paramedic students performed chest compression for 5 minutes on the floor and during ambulance transportation. Compression rate and depth and success and error rates of chest compression were determined using the Resusci Anne manikin with a PC SkillReporting System (Laerdal Medical). Integrated electromyography (i-EMG) values of eight different muscles were also recorded bilaterally during the first and last 30 seconds of compression. RESULTS: There was no significant difference in compression rate per minute (p = 0.232) and depth of chest compression (p = 0.174) between the two conditions. The success rate was significantly lower under the ambulance transportation condition than under the static condition (p = 0.0161). Compared with those under the static condition, the total i-EMG values were significantly lower for the multifidus (p = 0.0072) and biceps femoris (p < 0.0001) muscles and significantly higher for the deltoid (p = 0.0032), pectoralis major (p = 0.0037), triceps brachii (p = 0.0014), vastus lateralis (p < 0.0001), and gastrocnemius (p = 0.0004) muscles under the ambulance transportation condition. CONCLUSIONS: Chest compression is performed mainly through flexion and extension of the hip joint while kneeling on the floor and through the elbow and shoulder joints while standing in a moving ambulance. Therefore, the low quality of chest compression during ambulance transportation may be attributable to an altered technique of performing the procedure.

Determination of the appropriate catheter length for needle thoracostomy by using computed tomography scans of trauma patients in Japan.

BACKGROUND: Previous studies reported a high failure rate in relieving tension pneumothorax by needle thoracostomy, because the catheter was not sufficiently long to access the pleural space. The Advanced Trauma Life Support guideline recommends needle thoracostomy at the second intercostal space in the middle clavicular line using a 5.0-cm catheter, whereas the corresponding guideline in Japan does not mention a catheter length. It is necessary to measure the chest wall thickness (CWT) and determine the appropriate catheter length taking the differences of habitus in race and region into consideration. This study was designed to analyse CWT in Japanese trauma patients by computed tomography and to determine the percentage of patients whose pleural space would be accessible using a 5.0-cm catheter. PATIENTS AND METHODS: We performed a retrospective review of chest computed tomography of 256 adult Japanese trauma patients who were admitted to the level 1 trauma centre of Tokai University Hospital in Kanagawa, Japan between January and July 2008. In 256 patients, the CWT at 512 sites (left and right sides) was measured by chest computed tomography at the second intercostal space in the middle clavicular line. The frequency of measurement sites <5.0 cm was calculated simultaneously. The samples were divided according to gender, side (left and right), abbreviated injury scale (<3, ≧3), arm position during examination (up/down), and the existence or non-existence of associated injuries (pneumothorax, subcutaneous emphysema, and fracture of the sternum and ribs); the CWT of each group was compared. RESULTS: The mean CWT measured in 192 males and 64 females was 3.06±1.02 cm. The CWT values at 483 sites (94.3%) were less than 5.0 cm. The CWT of females was significantly greater than that of males (3.66 cm vs. 2.85 cm, p<0.0001), and patients with subcutaneous emphysema had greater CWTs than those without it (4.16 cm vs. 3.01 cm, p<0.0001). CONCLUSION: The mean CWT at the second intercostal space in the middle clavicular line was 3.06 cm. It is likely that over 94% of Japanese trauma patients could be treated with a 5.0-cm catheter.

Mass gathering medicine for the First East Asian Football Championship and the 24th European/South American Cup in Japan.

It is very important to collect and accumulate data of same-type events from the point of view of appropriate preparedness for mass gathering medicine. On the basis of the experience of the 2002 FIFA World Cup Korea/Japan, the Japanese Association of Disaster Medicine organized the emergency medical assistance team during large football events. The objective was to analyze all clinical presentations available to the on-site physicians during this event. The total number of patients was 51 (patient presentation rate: 0.25/1000 spectators). Trauma, abdominal pain and common cold were the main pathologies encountered. Eight patients were transported to hospital. Forty-one patients (80.4% of total) were treated within the medical station and were not transported to hospital. These dispositions were considered to lighten the burden imposed on activities of local emergency medical services. Sharing databases with local medical services and surveying the outcome of patients are needed to allow patient presentation provision.

Predictive model for estimating risk of crush syndrome: a data mining approach.

BACKGROUND: There is no standard triage method for earthquake victims with crush injuries because of a scarcity of epidemiologic and quantitative data. We conducted a retrospective cohort study to develop predictive models based on clinical data for crush injury in the Kobe earthquake. METHODS: The medical records of 372 patients with crush injuries from the Kobe earthquake were retrospectively analyzed. Twenty-one risk factors were assessed with logistic regression analysis for three outcomes relating to crush syndrome. Two types of predictive triage models--initial evaluation in the field and secondary assessment at the hospital--were developed using logistic regression analysis. Classification accuracy, Brier score and area under the receiver operating characteristic curve (AUC) were used to evaluate the model. RESULTS: The initial triage model, which includes pulse rate, delayed rescue, and abnormal urine color, has an AUC of 0.73. The secondary model, which includes WBC, tachycardia, abnormal urine color, and hyperkalemia, shows an AUC of 0.76. CONCLUSIONS: These triage models may be especially useful to nondisaster experts for distinguishing earthquake victims at high risk of severe crush syndrome from those at lower risk. Application of the model may allow relief workers to better utilize limited medical and transportation resources in the aftermath of a disaster.

Analysis of patient load data from the 2002 FIFA World Cup Korea/Japan.

INTRODUCTION: Past history of mass casualties related to international football games brought the importance of practical planning, preparedness, simulation training, and analysis of potential patient presentations to the forefront of emergency research. METHODS: The Japanese Ministry of Health, Labor, and Welfare established the Health Research Team (HRT-MHLW) for the 2002 FIFA World Cup game (FIFAWC). The HRT-MHLW collected patient data related to the games and analyzed the related factors regarding patient presentations. RESULTS: A total of 1661 patients presented for evaluation and care from all 32 games in Japan. The patient presentation rate per 1000 spectators per game was 1.21 and the transport-to-hospital rate was 0.05. The step-wise regression analysis identified that the patient presentations rate increased where access was difficult. As the number of total spectators increased, the patient presentation rate decreased. (p < 0.0001, r = 0.823, r2 = 0.677). CONCLUSION: In order to develop mass-gathering medical-care plans in accordance with the types and sizes of mass gatherings, it is necessary to collect data and examine risk factors for patient presentations for a variety of events.

Survival and cost analysis of fatalities of the Kobe earthquake in Japan.

OBJECTIVES: The authors investigated the dying patterns, and cause and preventability of deaths in a major earthquake disaster, and estimated the cost needed to enhance emergency medical services (EMS) response to prevent "unnecessary" deaths. METHODS: The authors reviewed autopsy data in the Hanshin-Awaji (Kobe) earthquake of 1995. A survival analysis was performed to determine the time course and pattern of dying of these deaths. A cost analysis to estimate acceptable cost for EMS to reduce fatalities was also performed. Potentially salvageable life-years based on expected life-years among fatalities were calculated and used to simulate an acceptable cost for an enhanced EMS disaster response. RESULTS: The authors analyzed 5,411 fatalities. More than 80% of these patients died within three hours. There were statistically significant differences in survival/dying patterns among causes of death. Thirteen percent of victims experienced a protracted death, which could have been prevented with earlier medical or surgical intervention. The monetary cost of these lost lives was estimated at approximately 600 million US dollars. CONCLUSIONS: Survival analysis revealed a significant population of potentially salvageable patients if more timely and appropriate medical intervention had been available immediately after the earthquake. Based on our cost analysis, and assuming a 1% annual probability of an earthquake and a 30% enhanced lifesaving capability of the EMS effort, approximately $ million dollars annually could be a reasonable expenditure to achieve the goal of reducing preventable deaths in disasters.