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Introduction of a Physician-Staffed Helicopter Emergency Medical Service in Eastern Shizuoka Prefecture in Japan
ORIGINAL RESEARCH
Introduction of a Physician-Staffed Helicopter Emergency Medical Service in Eastern Shizuoka Prefecture in Japan Kazuhiko Omori, MD, PhD, Hiromichi Ohsaka, MD, PhD, Kouhei Ishikawa, MD, Mariko Obinata, MD, Yasumasa Oode, MD, Akihiko Kondo, MD, Akio Kanda, MD, PhD, Mitsuhiro Fujii, MD, PhD, Mutsumi Sakurada, MD, PhD, Yasuaki Nakao, MD, PhD, Tetsu Suwa, MD, PhD, Ken Okamoto, MD, PhD, and Youichi Yanagawa, MD, PhD
Abstract Objective: To analyze the operating situation of a physicianstaffed helicopter emergency medical service in eastern Shizuoka prefecture. Methods: A retrospective analysis was performed using the conveyance records reported by staff members of the physicianstaffed helicopter. A comparison between 2007 (n = 619) and 2012 (n = 678) was performed. Results: There were no significant differences between the 2 groups with regard to the sex, ratio of cardiopulmonary arrest, and survival ratio. In contrast, the duration from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012 (53.7 vs 48.2 minutes, P < 0.0001). The average age in 2007 was significantly younger than in 2012 (55.7 vs 59.4 years, P < 0.01). The ratio of trauma case in the 2012 was higher than that in 2007 (47 vs 37%, P < 0.001). The ratio of severe cases in 2007 was higher than in 2012 (45 vs 39%, P < 0.05). Conclusion: Japan is an aging society. In eastern Shizuoka prefecture, the increase in the number of trauma and minor injury cases may have increased due to the emphasis on the importance of early medical intervention by the fire department.
Introduction To enable an earlier commencement of treatment, helicopters and other aircraft are used to carry doctors to the sites of emergencies in many countries. After the occurrence of many preventable disaster-related deaths during the acute phase of the Great Hanshin/Awaji earthquake in 1995, the Ministry of Health, Labour and Welfare decided to try to establish a
Shizuoka Hospital, Juntendo University, Shizuoka, Japan Address for correspondence: Kazuhiko Omori, MD, PhD, 1129 Nagaoka, Izunokuni City, Shizuoka 410-2295, Japan, [email protected] 1067-991X/$36.00 Copyright 2014 by Air Medical Journal Associates http://dx.doi.org/:10.1016/j.amj.2014.07.036 292
physician-staffed helicopter emergency medical service (HEMS) in 1999, which had not previously existed in Japan. The results of the trial in 2 prefectures (Okayama and Kanagawa) showed the efficacy of the HEMS,1 so the Ministry of Health, Labour and Welfare continued to promote the HEMS and the Japanese cabinet enacted a law to establish an HEMS in Japan in 2007. By February 2013, 40 helicopters had been deployed in 34 prefectures across Japan. The crews of physician-staffed helicopters generally consist of 1 pilot, 1 mechanic, 1 doctor, and 1 nurse. Several problems associated with the HEMS in Japan have been pointed out, such as the training system, shortage of heliports, and limitations of the service time.2,3 The indications for air evacuation in Japan are decided upon the receipt of the 119 (emergency) call based on the judgment of the emergency medical technician when he or she receives the dispatch request or is put in contact with the patient(s). When a physician-staffed helicopter is dispatched to a scene, the helicopter lands at a rendezvous point where permission for use has been granted in advance, and the patient(s) is transported there by an ambulance. In some cases, when the physician-staffed helicopter lands before the ambulance arrives, the physician and nurse are transported to the scene by another ambulance. After being examined by the physician, the patient undergoes emergency treatments and triage for transportation to the right hospital. An analysis of the HEMS in Japan revealed an increased survival rate among severe cases, and the cost-effectiveness of the program was also noted.4-6 The HEMS service in the western part of Shizuoka Prefecture commenced in 2001 and has been supported by Seirei Mikatahara General Hospital. In March 2004, service in the eastern part of the prefecture was added. Two helicopters cover all of Shizuoka Prefecture, with an arrival time within 20 minutes. Our hospital (Juntendo University Shizuoka Hospital) serves as the base hospital and is responsible for the eastern region of Shizuoka Prefecture, including the Izu Peninsula. This region, approximately 4,090 km2 in area, with a population of approximately 2 million, is mountainous, with only a few hospitals.7 The journey from the southern tip of the peninsula to the critical care medical center of our hospital takes 1.5 hours by Air Medical Journal 33:6
Figure 1. Distribution of Dispatch
Table 1. The Results of the Analysis Comparing 2007 and 2012 2007 (n ⫽ 619) Age (years) 55.7 ⫹ 1.0 Ratio of males (%) 66 Ratio of intrinsic diseases (%) 63 Ratio of extrinsic diseases (%) 37 Ratio of severe cases (%) 45 Ratio of cardiopulmonary arrest (%) 6 Time from request to hospital arrival (min) 53.7 ⫹ 0.6 Ratio of destinations (to our hospital) (%) 75 Survival ratio (%) 85 (n ⫽ 444)
2012 (n ⫽ 678) 59.4 ⫹ 0.9 64 53 47 39 8 48.2 ⫹ 0.6 75 86 (n ⫽ 504)
P Value ⬍.01 NS ⬍.001 ⬍.05 NS ⬍.0001 NS NS
NS ⫽ not significant.
ambulance but only 15 minutes by helicopter. Currently, only the most severe cases are transported using this HEMS. We herein introduce the results of our analysis of the operating situation of the HEMS in the eastern part of Shizuoka Prefecture.
Methods A retrospective analysis was performed using the conveyance records reported by staff members of the physicianstaffed helicopter. To analyze the operating situation of the HEMS in eastern Shizuoka Prefecture, a comparison between 2007 and 2012 was performed concerning factors such as the sex and age of patients, destination (to our hospital or others), ratio of intrinsic diseases, ratio of extrinsic diseases, cardiopulmonary arrest, severity, duration from the request November-December 2014
of the dispatch of the HEMS, and survival ratio among the patients who were transported to our hospital. The definition of severity was the level of abnormality of the vital signs (systolic blood pressure ⬍ 90 mm Hg, heart rate ⬎ 100 beats per minute, respiratory rate ⬎ 30 breaths per minute, SpO2 ⬍ 90% under room air, or consciousness disturbance at the scene), the anatomic severity in trauma cases, or based on the impression of the physicians. Statistical analysis was performed using the Student unpaired t-test and the chi-square test. Differences with values of P ⬍ .05 were considered to be statistically significant.
Results The number of patients who were transported by the HEMS in eastern Shizuoka Prefecture increased from its start in 2004 293
Figure 2. List of extrinsic diseases. The number of trauma cases involving soft tissue injury and fractures increase in 2012 compared with 2007.
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Figure 3. List of intrinsic diseases. There is no specific trends in 2012 compared with 2007.
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to 2007 when up to 600 requests for dispatch were made. Between 2007 and 2010, the number of patients transported was decreasing, and after 2010, the number of patients increased to 616 dispatch requests (Fig. 1). The results of the comparison between 2007 and 2012 are shown in Table 1. There were no significant differences between the 2 groups regarding sex, ratio of cardiopulmonary arrest, and survival ratio. In contrast, the average age in 2007 was significantly
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younger than that in 2012. The ratio of extrinsic diseases in 2012 was higher than that in 2007. The details of the intrinsic and extrinsic diseases are shown in Figures 2 and 3. The number of trauma cases involving soft tissue injury and fractures increased in 2012 compared with 2007. The ratio of severe cases in 2007 was higher than that in 2012. The duration from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012. Air Medical Journal 33:6
Discussion Our results showed that the average age of patients was older in 2012 in comparison with 2007. The Ministry of Internal Affairs and Communications reported that the ratio of the population over 65 years old was predicted to have reached 21% in 2007 and 24% in 2012. Japan is an aging society, with the fastest rate of aging of any country in the world, so it is logical that the average age increased in our report. An aging society is generally associated with an increase in the number of intrinsic diseases and cases of cardiopulmonary arrest. However, our report showed that there was an increase in the number of extrinsic diseases and a decrease in the severity of cases. This is likely because the physicians of the HEMS in eastern Shizuoka Prefecture emphasize that the main purpose of the HEMS is early medical intervention, not early transportation to a hospital. In addition, overtriage concerning the request of the HEMS was allowed because the efficacy of the HEMS has recently been reported for extrinsic diseases.8,9 Accordingly, the number of minor injuries of extrinsic diseases treated in our system increased. In contrast, cases with severe intrinsic disease or cardiopulmonary cases were mainly transported to or between hospitals. A shortage of announcements to local hospitals in the Izu Peninsula concerning the efficacy of the HEMS or a deterioration of the background of patients, such as those requiring full-scale assistance with their activities of daily living, because of the aging of society may be responsible for the lack of an increase in the transportation of severe cases with intrinsic disease or cardiopulmonary arrest. Our report showed that the duration of time from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012. We hold monthly meetings about the management of the HEMS in eastern Shizuoka Prefecture. These meetings, which were not focused on triage but rather instead on ways to shorten the transportation time and the implemented practices, appear to have helped shorten the transportation time. Specifically, the helicopter coordination team arranges for the medical facilities to take in the emergency patient before the arrival of the helicopter at the site. There is currently a bigger issue regarding the time taken for ambulance transport of critical cases that are not part of the HEMS. In order to facilitate the work of the HEMS, the fire department emergency personnel are working on introducing a keyword system. For example, when the fire department receives the first call regarding a high-energy accident, such as a collision between a vehicle and a person, both a request to the HEMS and an order to dispatch the ambulance are performed at the same time. Although the fire department emergency personnel can also make the first request for the HEMS when they receive an order of dispatch, this request is sometimes canceled after the assessment of the patient by the ambulance service upon arrival at the emergency site. Accordingly, we permit certain rates of cancelations by the fire department emergency personnel to encourage the use of the HEMS. November-December 2014
One of the limitations associated with this study was that we were not able to use a standardized definition of patients, such as the Abbreviated Injury Scale, Injury Severity Score, or Trauma and Injury Severity Score. One of the reasons is that approximately 25% of the cases were transported to other medical facilities, and information about the anatomic severity based on a computed tomographic scan was not obtained. In addition, there was no standard method to evaluate the severity of intrinsic and extrinsic diseases at the same time, except for monitoring the vital signs. We are now investigating whether measuring the lactate level is useful for evaluating the severity of both intrinsic and extrinsic diseases.
Conclusion Japan is an aging society. In eastern Shizuoka Prefecture, the increase in the number of trauma and minor injury cases may have increased because of the emphasis on the importance of early medical intervention by the fire department.
References 1. Obama K. Doctor Helicopter [in Japanese]. Tokyo: Herusu Cooperation; 2003:1-40. 2. Takamatus G, Sakamoto T. A physician-staffed helicopter emergency medical service. Kurume Med J. 2009;72:259-266. 3. Matsumoto H, Kanemaru K, Hara Y, et al. Development of an educational program for the helicopter emergency medical services in Japan. Air Med J. 2013;32:84-87. 4. Takayama H. Interim report of efficacy of helicopter emergency medical services in Japan. J Jpn Soc Aeromed Serv. 2012;13:41-43. 5. Kon A, Miura K, Nodazu T, et al. Efficacy of helicopter emergency medical services in Aomori prefecture. J Hachinohe Hosp. 2011;29:18-28. 6. Matsumoto H, Mashiko K, Hara Y, et al. Effectiveness of a "doctor-helicopter" system in Japan. Isr Med Assoc J. 2006;8:8-11. 7. Omori K, Sato S, Sumi Y, et al. The analysis of efficacy for AutoPulse™ system in flying helicopter. Resuscitation. 2013;84:1045-1050. 8. Andruszkow H, Lefering R, Frink M, et al. Survival benefit of helicopter emergency medical services compared to ground emergency medical services in traumatized patients. Crit Care. 2013;17:R124. 9. Taylor C, Jan S, Curtis K, et al. The cost-effectiveness of physician staffed Helicopter Emergency Medical Service (HEMS) transport to a major trauma centre in NSW, Australia. Injury. 2012;43:1843-1849.
295
Introduction of a Physician-Staffed Helicopter Emergency Medical Service in Eastern Shizuoka Prefecture in Japan Kazuhiko Omori, MD, PhD, Hiromichi Ohsaka, MD, PhD, Kouhei Ishikawa, MD, Mariko Obinata, MD, Yasumasa Oode, MD, Akihiko Kondo, MD, Akio Kanda, MD, PhD, Mitsuhiro Fujii, MD, PhD, Mutsumi Sakurada, MD, PhD, Yasuaki Nakao, MD, PhD, Tetsu Suwa, MD, PhD, Ken Okamoto, MD, PhD, and Youichi Yanagawa, MD, PhD
Abstract Objective: To analyze the operating situation of a physicianstaffed helicopter emergency medical service in eastern Shizuoka prefecture. Methods: A retrospective analysis was performed using the conveyance records reported by staff members of the physicianstaffed helicopter. A comparison between 2007 (n = 619) and 2012 (n = 678) was performed. Results: There were no significant differences between the 2 groups with regard to the sex, ratio of cardiopulmonary arrest, and survival ratio. In contrast, the duration from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012 (53.7 vs 48.2 minutes, P < 0.0001). The average age in 2007 was significantly younger than in 2012 (55.7 vs 59.4 years, P < 0.01). The ratio of trauma case in the 2012 was higher than that in 2007 (47 vs 37%, P < 0.001). The ratio of severe cases in 2007 was higher than in 2012 (45 vs 39%, P < 0.05). Conclusion: Japan is an aging society. In eastern Shizuoka prefecture, the increase in the number of trauma and minor injury cases may have increased due to the emphasis on the importance of early medical intervention by the fire department.
Introduction To enable an earlier commencement of treatment, helicopters and other aircraft are used to carry doctors to the sites of emergencies in many countries. After the occurrence of many preventable disaster-related deaths during the acute phase of the Great Hanshin/Awaji earthquake in 1995, the Ministry of Health, Labour and Welfare decided to try to establish a
Shizuoka Hospital, Juntendo University, Shizuoka, Japan Address for correspondence: Kazuhiko Omori, MD, PhD, 1129 Nagaoka, Izunokuni City, Shizuoka 410-2295, Japan, [email protected] 1067-991X/$36.00 Copyright 2014 by Air Medical Journal Associates http://dx.doi.org/:10.1016/j.amj.2014.07.036 292
physician-staffed helicopter emergency medical service (HEMS) in 1999, which had not previously existed in Japan. The results of the trial in 2 prefectures (Okayama and Kanagawa) showed the efficacy of the HEMS,1 so the Ministry of Health, Labour and Welfare continued to promote the HEMS and the Japanese cabinet enacted a law to establish an HEMS in Japan in 2007. By February 2013, 40 helicopters had been deployed in 34 prefectures across Japan. The crews of physician-staffed helicopters generally consist of 1 pilot, 1 mechanic, 1 doctor, and 1 nurse. Several problems associated with the HEMS in Japan have been pointed out, such as the training system, shortage of heliports, and limitations of the service time.2,3 The indications for air evacuation in Japan are decided upon the receipt of the 119 (emergency) call based on the judgment of the emergency medical technician when he or she receives the dispatch request or is put in contact with the patient(s). When a physician-staffed helicopter is dispatched to a scene, the helicopter lands at a rendezvous point where permission for use has been granted in advance, and the patient(s) is transported there by an ambulance. In some cases, when the physician-staffed helicopter lands before the ambulance arrives, the physician and nurse are transported to the scene by another ambulance. After being examined by the physician, the patient undergoes emergency treatments and triage for transportation to the right hospital. An analysis of the HEMS in Japan revealed an increased survival rate among severe cases, and the cost-effectiveness of the program was also noted.4-6 The HEMS service in the western part of Shizuoka Prefecture commenced in 2001 and has been supported by Seirei Mikatahara General Hospital. In March 2004, service in the eastern part of the prefecture was added. Two helicopters cover all of Shizuoka Prefecture, with an arrival time within 20 minutes. Our hospital (Juntendo University Shizuoka Hospital) serves as the base hospital and is responsible for the eastern region of Shizuoka Prefecture, including the Izu Peninsula. This region, approximately 4,090 km2 in area, with a population of approximately 2 million, is mountainous, with only a few hospitals.7 The journey from the southern tip of the peninsula to the critical care medical center of our hospital takes 1.5 hours by Air Medical Journal 33:6
Figure 1. Distribution of Dispatch
Table 1. The Results of the Analysis Comparing 2007 and 2012 2007 (n ⫽ 619) Age (years) 55.7 ⫹ 1.0 Ratio of males (%) 66 Ratio of intrinsic diseases (%) 63 Ratio of extrinsic diseases (%) 37 Ratio of severe cases (%) 45 Ratio of cardiopulmonary arrest (%) 6 Time from request to hospital arrival (min) 53.7 ⫹ 0.6 Ratio of destinations (to our hospital) (%) 75 Survival ratio (%) 85 (n ⫽ 444)
2012 (n ⫽ 678) 59.4 ⫹ 0.9 64 53 47 39 8 48.2 ⫹ 0.6 75 86 (n ⫽ 504)
P Value ⬍.01 NS ⬍.001 ⬍.05 NS ⬍.0001 NS NS
NS ⫽ not significant.
ambulance but only 15 minutes by helicopter. Currently, only the most severe cases are transported using this HEMS. We herein introduce the results of our analysis of the operating situation of the HEMS in the eastern part of Shizuoka Prefecture.
Methods A retrospective analysis was performed using the conveyance records reported by staff members of the physicianstaffed helicopter. To analyze the operating situation of the HEMS in eastern Shizuoka Prefecture, a comparison between 2007 and 2012 was performed concerning factors such as the sex and age of patients, destination (to our hospital or others), ratio of intrinsic diseases, ratio of extrinsic diseases, cardiopulmonary arrest, severity, duration from the request November-December 2014
of the dispatch of the HEMS, and survival ratio among the patients who were transported to our hospital. The definition of severity was the level of abnormality of the vital signs (systolic blood pressure ⬍ 90 mm Hg, heart rate ⬎ 100 beats per minute, respiratory rate ⬎ 30 breaths per minute, SpO2 ⬍ 90% under room air, or consciousness disturbance at the scene), the anatomic severity in trauma cases, or based on the impression of the physicians. Statistical analysis was performed using the Student unpaired t-test and the chi-square test. Differences with values of P ⬍ .05 were considered to be statistically significant.
Results The number of patients who were transported by the HEMS in eastern Shizuoka Prefecture increased from its start in 2004 293
Figure 2. List of extrinsic diseases. The number of trauma cases involving soft tissue injury and fractures increase in 2012 compared with 2007.
322 ;2 :2
92 82
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Figure 3. List of intrinsic diseases. There is no specific trends in 2012 compared with 2007.
322 ;2 :2
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to 2007 when up to 600 requests for dispatch were made. Between 2007 and 2010, the number of patients transported was decreasing, and after 2010, the number of patients increased to 616 dispatch requests (Fig. 1). The results of the comparison between 2007 and 2012 are shown in Table 1. There were no significant differences between the 2 groups regarding sex, ratio of cardiopulmonary arrest, and survival ratio. In contrast, the average age in 2007 was significantly
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younger than that in 2012. The ratio of extrinsic diseases in 2012 was higher than that in 2007. The details of the intrinsic and extrinsic diseases are shown in Figures 2 and 3. The number of trauma cases involving soft tissue injury and fractures increased in 2012 compared with 2007. The ratio of severe cases in 2007 was higher than that in 2012. The duration from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012. Air Medical Journal 33:6
Discussion Our results showed that the average age of patients was older in 2012 in comparison with 2007. The Ministry of Internal Affairs and Communications reported that the ratio of the population over 65 years old was predicted to have reached 21% in 2007 and 24% in 2012. Japan is an aging society, with the fastest rate of aging of any country in the world, so it is logical that the average age increased in our report. An aging society is generally associated with an increase in the number of intrinsic diseases and cases of cardiopulmonary arrest. However, our report showed that there was an increase in the number of extrinsic diseases and a decrease in the severity of cases. This is likely because the physicians of the HEMS in eastern Shizuoka Prefecture emphasize that the main purpose of the HEMS is early medical intervention, not early transportation to a hospital. In addition, overtriage concerning the request of the HEMS was allowed because the efficacy of the HEMS has recently been reported for extrinsic diseases.8,9 Accordingly, the number of minor injuries of extrinsic diseases treated in our system increased. In contrast, cases with severe intrinsic disease or cardiopulmonary cases were mainly transported to or between hospitals. A shortage of announcements to local hospitals in the Izu Peninsula concerning the efficacy of the HEMS or a deterioration of the background of patients, such as those requiring full-scale assistance with their activities of daily living, because of the aging of society may be responsible for the lack of an increase in the transportation of severe cases with intrinsic disease or cardiopulmonary arrest. Our report showed that the duration of time from the request of dispatch to arrival at the hospital in 2007 was significantly longer than that in 2012. We hold monthly meetings about the management of the HEMS in eastern Shizuoka Prefecture. These meetings, which were not focused on triage but rather instead on ways to shorten the transportation time and the implemented practices, appear to have helped shorten the transportation time. Specifically, the helicopter coordination team arranges for the medical facilities to take in the emergency patient before the arrival of the helicopter at the site. There is currently a bigger issue regarding the time taken for ambulance transport of critical cases that are not part of the HEMS. In order to facilitate the work of the HEMS, the fire department emergency personnel are working on introducing a keyword system. For example, when the fire department receives the first call regarding a high-energy accident, such as a collision between a vehicle and a person, both a request to the HEMS and an order to dispatch the ambulance are performed at the same time. Although the fire department emergency personnel can also make the first request for the HEMS when they receive an order of dispatch, this request is sometimes canceled after the assessment of the patient by the ambulance service upon arrival at the emergency site. Accordingly, we permit certain rates of cancelations by the fire department emergency personnel to encourage the use of the HEMS. November-December 2014
One of the limitations associated with this study was that we were not able to use a standardized definition of patients, such as the Abbreviated Injury Scale, Injury Severity Score, or Trauma and Injury Severity Score. One of the reasons is that approximately 25% of the cases were transported to other medical facilities, and information about the anatomic severity based on a computed tomographic scan was not obtained. In addition, there was no standard method to evaluate the severity of intrinsic and extrinsic diseases at the same time, except for monitoring the vital signs. We are now investigating whether measuring the lactate level is useful for evaluating the severity of both intrinsic and extrinsic diseases.
Conclusion Japan is an aging society. In eastern Shizuoka Prefecture, the increase in the number of trauma and minor injury cases may have increased because of the emphasis on the importance of early medical intervention by the fire department.
References 1. Obama K. Doctor Helicopter [in Japanese]. Tokyo: Herusu Cooperation; 2003:1-40. 2. Takamatus G, Sakamoto T. A physician-staffed helicopter emergency medical service. Kurume Med J. 2009;72:259-266. 3. Matsumoto H, Kanemaru K, Hara Y, et al. Development of an educational program for the helicopter emergency medical services in Japan. Air Med J. 2013;32:84-87. 4. Takayama H. Interim report of efficacy of helicopter emergency medical services in Japan. J Jpn Soc Aeromed Serv. 2012;13:41-43. 5. Kon A, Miura K, Nodazu T, et al. Efficacy of helicopter emergency medical services in Aomori prefecture. J Hachinohe Hosp. 2011;29:18-28. 6. Matsumoto H, Mashiko K, Hara Y, et al. Effectiveness of a "doctor-helicopter" system in Japan. Isr Med Assoc J. 2006;8:8-11. 7. Omori K, Sato S, Sumi Y, et al. The analysis of efficacy for AutoPulse™ system in flying helicopter. Resuscitation. 2013;84:1045-1050. 8. Andruszkow H, Lefering R, Frink M, et al. Survival benefit of helicopter emergency medical services compared to ground emergency medical services in traumatized patients. Crit Care. 2013;17:R124. 9. Taylor C, Jan S, Curtis K, et al. The cost-effectiveness of physician staffed Helicopter Emergency Medical Service (HEMS) transport to a major trauma centre in NSW, Australia. Injury. 2012;43:1843-1849.
295