Writer Profile

Motoyasu Yamazaki
Other : Director for Medical Affairs, Health and Medical Bureau, Kanagawa PrefectureKeio University alumni

Motoyasu Yamazaki
Other : Director for Medical Affairs, Health and Medical Bureau, Kanagawa PrefectureKeio University alumni
2024/12/04
Preventable Disaster Death (PDD)
Are you familiar with the term "Preventable Disaster Death"? Understanding the meaning of this term, including its evolution over time, will surely help in understanding modern disaster medicine in Japan. I would like to discuss its significance.
"Preventable Disaster Death" is defined as a disaster death that could potentially have been saved if peacetime emergency medical care had been provided. Following the Great Hanshin-Awaji Earthquake, it was reported that approximately 500 (about 7.8%) of the 6,434 fatalities were potentially "Preventable Disaster Deaths" due to delays in initial emergency care. Since then, preventing "Preventable Disaster Deaths" has become the primary goal of disaster medicine in Japan.
In the Great Hanshin-Awaji Earthquake, it was pointed out that while the functions of medical institutions within the disaster area significantly declined immediately after the disaster, there was a shortage of medical teams entering the area from outside to provide relief, a lack of means to transport severely injured patients out of the area, and a lack of information-sharing infrastructure. Using these lessons, systems that form the backbone of current disaster medicine were established, such as Disaster Base Hospitals, DMAT (Disaster Medical Assistance Team), wide-area medical transportation, and EMIS (Emergency Medical Information System). It can truly be said that the history of modern disaster medicine in Japan began with the Great Hanshin-Awaji Earthquake.
The concept of the so-called "72-hour survival wall" also originated from the Great Hanshin-Awaji Earthquake. It was reported that the percentage of survivors among those rescued dropped rapidly from 74.9% (518/692) on the first day to 24.2% (195/806) on the second day, 15.1% (133/883) on the third day, and 5.4% (26/484) on the fourth day. Consequently, the importance of rapid rescue and emergency medical services to break through the "72-hour wall" became a shared understanding.
Furthermore, the causes of death were dominated by trauma-related deaths, or so-called "direct disaster deaths," with 77% due to suffocation or crushing by collapsed houses and 9% due to burning or burns from fires. This contributed to the widespread perception that "disaster medicine ≈ emergency medicine immediately after the disaster." Incidentally, I graduated from the Juku School of Medicine in 1995, the very year the Great Hanshin-Awaji Earthquake occurred, which was also the catalyst for my path as an emergency physician.
Preventable Trauma Death (PTD)
In fact, the concept of "Preventable Disaster Death" has its roots in "Preventable Trauma Death" for severe trauma patients in peacetime. This refers to cases where it is believed the patient would not have died if they had received appropriate medical care or if standard procedures had been performed after the injury. Generally, the probability of survival (Ps) is calculated (TRISS method) using factors such as the patient's age, consciousness level at the first visit, blood pressure/pulse, and the degree of physical damage obtained through diagnostic imaging or surgery. Cases that result in death despite a Ps ≥ 0.5 are first classified as "Unexpected Death." Furthermore, after a peer review by multiple independent trauma specialists, it is determined whether it was a "Preventable Trauma Death." Various measures are then taken to prevent such deaths, helping to improve the quality of medical care.
This concept first became widespread in the United States, but it began to attract attention in Japan following a 2001 Health and Labour Sciences Research study. A questionnaire survey of emergency and trauma centers nationwide revealed that, excluding cases of cardiopulmonary arrest upon arrival, a staggering 38.6% of trauma deaths over one year were judged to be "highly likely preventable trauma deaths." This situation was roughly equivalent to that of the United States 30 years prior, and significant regional and institutional disparities within Japan were also pointed out. These results were shocking to Japanese emergency medical professionals, especially since the survey targeted only Emergency and Trauma Centers (so-called tertiary emergency hospitals) that are supposed to provide the highest level of emergency medical care in Japan.
In response to these results, training systems for standard initial trauma care and relief, such as JATEC (Japan Advanced Trauma Evaluation and Care) and JPTEC (Japan Prehospital Trauma Evaluation and Care), as well as emergency transport means like doctor-helicopter services, were established and spread nationwide. In particular, as of 2024, 57 doctor-helicopters are in operation across 47 prefectures, and they are utilized as an important means of patient transport during disasters, including the Noto Peninsula Earthquake. Some regions have also implemented their own measures. For example, in Yokohama City, two of the nine Emergency and Trauma Centers (Saiseikai Yokohama-shi Tobu Hospital and Yokohama City University Medical Center) were designated as "Yokohama City Major Trauma Centers" in 2014 to centralize emergency transport and trauma physicians. A verification report in 2022 stated that this has had a certain effect on reducing "Preventable Trauma Deaths."
While I was at Saiseikai Yokohama-shi Tobu Hospital, I also served as the director of the Yokohama City Major Trauma Center. As symbolized by the phrase "Trauma is the neglected disease of modern society," I felt firsthand the importance of not dismissing severe trauma as an "unfortunate accident" but recognizing it as a "disease that will inevitably occur with a certain probability in a region" and responding by building a system for the entire community. This way of thinking has a high affinity with preventing the aforementioned "Preventable Disaster Deaths"—that is, "saving trauma patients immediately after a disaster through emergency medical care"—and it can be said that the perception of "disaster medicine ≈ emergency medicine" exists as an underlying current among Japanese professionals.
Disaster-Related Death
However, on the other hand, saving lives during a disaster is no longer necessarily just a matter of emergency medical care in the early stages. In particular, the overwhelming majority of deaths in the Great East Japan Earthquake were due to drowning from the tsunami. Since many who escaped the tsunami were uninjured, it was a disaster where the conventional method of "saving the injured immediately after the disaster through emergency medical care" did not apply. Furthermore, because it was an area with an aging population, it was characteristic that many disaster victims developed illnesses such as pneumonia because it became difficult to maintain health during evacuation life.
Even in such a situation, "Preventable Disaster Deaths" still existed. According to a report by Iwate Medical University, which investigated the causes of death for 153 people who died in the 20 days following the disaster at 15 hospitals in the coastal areas of Iwate Prefecture, 63 people (41.2%) died from causes related to the disaster. Of these, 28 (18.3%) were considered "potentially preventable disaster deaths," with causes analyzed as deterioration of the living environment, decline in hospital functions, breakdown of information-sharing functions, and delays in early medical intervention.
In other words, rather than acute emergency care or surgical treatment, chronic phase medical care and internal medicine treatment—addressing difficulties in continuing treatment for chronic diseases, drug shortages, and infectious diseases—came into focus. As a result, it was recognized that to prevent "Preventable Disaster Deaths," it is important to have a bird's-eye view of the entire region from immediately after the disaster to the chronic phase, and to develop human resources and networks that coordinate across various organizations and medical teams. Following the Great East Japan Earthquake, "disaster-related death" began to attract attention as a cause of "Preventable Disaster Death," in addition to "direct death" such as injuries from collapsed houses. In the subsequent Kumamoto Earthquake, while there were 50 direct deaths, there were over 200 related deaths. Consequently, "disaster-related death" is now receiving even more attention, and it is recognized that preventing this also leads to preventing "Preventable Disaster Deaths."
Also, during the Great East Japan Earthquake, coastal hospitals suffered immense damage and became unable to continue treatment, leading to frequent "hospital evacuations" where all inpatients were moved inland. In this context, I would like to mention Futaba Hospital, located about 4.5 km from the Fukushima Daiichi Nuclear Power Plant, which was forced to evacuate all its inpatients. Approximately 400 inpatients and residents, including those from related facilities, were evacuated by bus, but a very tragic situation occurred where about 50 people died during or immediately after the move. Naturally, they did not die from radiation exposure. Deaths associated with such evacuation actions are "disaster-related deaths," and the thought "Was this not also a preventable disaster death?" is shared by many disaster medical professionals.
Moving a large group of people who require continuous medical care over long distances by bus inherently carries great risks, and the period immediately following an earthquake, tsunami, or nuclear accident is one of extreme chaos. Safely transporting a large number of patients over long distances without interrupting medical care in the midst of a disaster is an extremely difficult task. However, after this painful experience, the system for long-distance transport of many patients while continuing medical care was strengthened, centered on DMAT and DPAT (Disaster Psychiatric Assistance Team). As a result, in the subsequent Kumamoto Earthquake (transporting 1,459 people from 11 hospitals) and the 2019 Boso Peninsula Typhoon (transporting 99 people from one hospital to 20 hospitals inside and outside the prefecture), no deaths occurred during transport.
Such activities were also repeated during the COVID-19 pandemic. For example, in the response to the Diamond Princess cruise ship in 2020, where I served as a DMAT member for transport duties, 769 COVID-19 positive individuals were transported over long distances to 16 prefectures, from Miyagi in the north to Osaka in the west, and admitted to hospitals in various locations. This was possible precisely because the experience of disaster medicine centered on DMAT was utilized.
At the time of the Great Hanshin-Awaji Earthquake, patient transport out of the disaster area was envisioned for the emergency treatment of trauma patients with conditions like crush syndrome. Now, however, a chronic-phase perspective has been added, aiming for the continuation of medical care that was already being provided before the disaster.
Evacuation Coordination in the Noto Peninsula Earthquake
In January 2024, as a DMAT member within the Health, Medical, and Welfare Coordination Headquarters of the Ishikawa Prefectural Government, I was in charge of the practical coordination for evacuating residents of elderly welfare facilities from the severely damaged Oku-Noto region to areas south of Kanazawa City, or to other prefectures such as Toyama, Fukui, and Aichi. I would like to reflect on the response during the Noto Peninsula Earthquake.
By January, when it became certain that water outages would be prolonged, mid-winter had arrived, and securing medical and nursing care personnel was extremely difficult, many hospitals and social welfare facilities were forced to transport inpatients and residents to areas south of Kanazawa City or outside the prefecture. According to the Japanese Association for Disaster Medicine, the number of inpatients reached 915 and residents 701; if cases where people moved on their own are included, the total is thought to be about 2,000. Because so many evacuees were admitted at the same time, hospitals and welfare facilities near Kanazawa City became full, and emergency medical care in Kanazawa City became strained. However, by utilizing cooperation with administrative agencies, DMAT, the Self-Defense Forces, doctor-helicopters, care managers, and others, the transport itself was generally carried out safely. In that sense, it can be said that "Preventable Disaster Deaths" were prevented and "disaster-related deaths" were reduced.
However, according to a report by the Japanese Association for Disaster Medicine, as of June 4, 2024, six months later, only 5 out of 68 people transported from social welfare facilities in the disaster area to Aichi Prefecture have been able to return to Ishikawa Prefecture. Fifty-one are still hospitalized or in facilities within Aichi Prefecture, 4 have transferred to other prefectures, and 8 have already passed away in Aichi Prefecture.
It was a situation where we had no choice but to transport them far away to avoid "disaster-related deaths," and the people transported included many of the very elderly. However, taking these results seriously, I cannot help but deeply reconsider whether my coordination within the Ishikawa Prefectural Government truly contributed to the happiness of the disaster victims, and what the correct answer was. Perhaps we should have prioritized the option of remaining in the local disaster area, even while accepting the risks of "disaster-related death" or "Preventable Disaster Death"? In other words, the question of whether there was something more important to cherish than "preventing disaster death" weighs heavily on my heart as someone involved in coordinating the long-distance transport of many disaster victims.
ACP (Advance Care Planning: Jinsei Kaigi)
Currently, the Ministry of Health, Labour and Welfare advocates the "Guidelines on the Process of Medical and Care Decision-Making at the End of Life." It recommends that medical care and care received at the end of life should be based on the individual's decision-making, with the family and the medical/care team discussing it with the individual repeatedly in advance. Such a forum and process for discussion is called Advance Care Planning (Jinsei Kaigi), and its promotion is being encouraged. As a method of decision-making, Shared Decision Making (SDM), where everyone discusses and thinks together rather than leaning unilaterally toward the thoughts of only the individual, only the family, or only the medical/care team, is recommended.
Conventionally, such discussions tended to be limited to cancer patients and to the terminal stage where the time of death can be clearly perceived. Now, however, it is said that discussions should take place even for non-cancer patients and not just when recognizing a clear terminal stage, but also in everyday life. Furthermore, since an individual's will can change, it is required to always discuss and reconsider each time.
In fact, in 2014, the Japanese Association for Acute Medicine, the Japanese Society of Intensive Care Medicine, and the Japanese Circulation Society proposed the "Guidelines for End-of-Life Care in Emergency and Intensive Care — Recommendations from Three Societies." These target emergency patients and heart disease patients, and in 2025, a revision to a four-society joint guideline, including the Japanese Society for Palliative Medicine, is planned. Generally, there is a thought that "emergency patients should first be saved with all one's might," but on the other hand, it might be said that there are things in the world of emergency medicine that should be prioritized over simply "saving a life."
In that sense, it is possible that similar values could arise in disaster medicine. Of course, "direct death" should be avoided as much as possible, and it remains important to prevent "Preventable Disaster Deaths," including "disaster-related deaths." However, whether "preventing disaster death" should be the top priority in everything may be something that cannot be understood without empathizing with and unraveling the disaster victim's own life.
To that end, what kind of life values do they usually hold? What do they want to prioritize at the final stage of their life? Whether in everyday life or when an emergency or disaster occurs, communication that involves discussing things each time and exploring the individual's happiness will likely be required of people in all positions.
※所属・職名等は本誌発刊当時のものです。