The island area in Tokyo refers to the Izu and Ogasawara Islands, and has about 26,000 inhabitants on 11 inhabited islands. Tokyo Metropolitan Hiroo Hospital, as the main island hospital in Tokyo, has been working to respond to a wide range of medical needs on these remote islands, including emergency patients. There are no doctor-free inhabited remote islands in Tokyo, as all islands have medical institutions with doctors. The islands are roughly divided into three groups according to population size. At present, emergency patients in the island area of Tokyo are transported mainly by the Tokyo Fire Department’s helicopter, in the case of the Izu Islands, and by the Maritime Self-Defense Force aircraft and helicopters via the Iwo Island, in the case of the Ogasawara Islands. This system for emergency transport of emergency patients on islands by air was the first of its kind in Japan. Its history dates to the enforcement of the Remote Island Promotion Law in 1953. To date, only one accidental landing incident has been reported. The number of transport cases per year was 272 on average from 2009 to 2018, and has been slightly decreasing over time. The average number of hospitalizations at Hiroo Hospital was 219, accounting for 81% of the total. The number of transport cases is generally proportional to the population size. For Oshima patients, the time between the request and arrival at the hospital is over two hours, and for those in the Ogasawara Islands, nearly 10 hours. Distance and travel time are roughly proportional. Cerebrovascular, cardiovascular, and digestive diseases are the leading reasons for hospitalization, and a wide range of emergency disease cases were treated, including orthopedic trauma cases and respiratory diseases, followed by decompression sickness and otolaryngology cases. There are two major issues that need to be addressed: controlling the number of transport cases and innovating the transport system.
