We think that the current useful functions of the Internet to HISs are categorized into 1) enhancement of personal private communications among health care staffs using electronic mail service (e-mail), 2) transferring clinical information about patients among two hospitals or clinics for consultations or decision support using file transfer protocol(FTP) or e-mail, 3) retrieval of up-to-date medical information with World Wide Web (WWW), Gopher, WAIS and database retrieval services, 4) discussion among health care providers and researchers using NetNews, electronic mailing list, and real-time video chat system like CUSeeMe, 5) usage of various electronic textbook distributed in the world, and 6) share of common knowledge or data which can be used among several hospitals. Although other attractive functions like tele-surgery are also available in near future of course, above functions are currently at hand if local area network in a hospital is connected to the Internet.!
To use the functions of the Internet effectively from HISs, it is important that all the staffs in the hospital have to be able to access such services just on the same computer terminals of HIS that they use for daily health care jobs, because their demands for information retrieval or communications with other experts occur while entering clinical orders from the terminal, making a therapeutic plan based on the labo results on the display and so on.
At the University of Tokyo Hospital, the hospital computer network is connected, with a firewall gateway, to the campus high speed LAN which is connected to the Internet. Connected this hospital computer network, there are about 450 UNIX workstations, with which physicians and nursing staffs enter clinical orders, see labo data and schedule of next visit for patients, in outpatient clinics and wards. Whenever a user requires electronic communications or world wide useful information, he or she can enjoy all the attractive services of the Internet directly from the workstation using pre-installed applications , e.g., Mosaic for accessing to WWW or Gopher server, e-mail client program, telnet program for connecting on-line MEDLINE services provided by the medical library of the university outside the hospital or University Hospital Information Network (UMIN). The statistics of mail server shows that about 60 e-mails a day are sent from inside the hospital to outside, and about 80 e-mails a day are received from outside in average during February '95. Another statistics shows that nursing staffs are active users of the e-mail system within the hospital. The reason is probably that e-mail system assists personal communications with their intimate colleagues whose working time are different. As regarding WWW, junior residents often uses Mosaic on the workstations at staff rooms in ward floor, and access to the several electronic textbooks and educational WWW pages for clinical case presentation which are experimentally served at UMIN, Osaka Medical School, University of Nagoya, and other several sites of United States.
The application of the Internet to HIS is not only for communications at one hospital connected to the Internet, but for communications of inter-hospitals/clinics. The UMIN project, which is started in 1988 aiming to construct nation-wide computer network among all national university hospitals in Japan, serves the various useful information resources to the world. Through the Internet, hospitals can also use the hardware resources to archive and serve their own information which is useful for other hospitals. Sharing medical knowledge in the UMIN computer center with the clinics in the district was experimented via the Internet in 1994 by us, and Hi-Vision Promotion Center, and color photographic, high resolution images of pathological samples could be transferred successfully via the Internet as well as the explanations and patients' profile data. Through this experimental project, it was found that the Internet is feasible for sharing medical knowledge between university hospitals and the clinics in the districts.
Since the Internet is essential environment for recent HISs, the discussion of the security problem is inevitable. We are now starting the investigation of feasibility and implications of privacy enhanced mail (PEM) technique adapted for hospital environment.