 and sometimes fragile machine, as new plans are set into motion for exploring space. New medical challenges will have to be met. Previous space flights have demonstrated the physiological changes that may be expected after living in a microgravity environment. Areas of particular concern include cardiovascular deconditioning, loss of muscle and bone mass, and changes in blood chemistry. In addition to the physiological changes, astronauts and scientists on space station will need to cope with common ailments such as toothaches, as well as more serious medical conditions such as kidney stones. Crew members must also be prepared to face many of the hazards which are found in comparable industrial settings on Earth. With longer missions, larger crews, and the complexities of a medical rescue, the health of the crew will be an important factor to the success of the mission. The Space Station Health Maintenance Facility, or HMF, will provide necessary in-flight medical care, including prevention, diagnosis, treatment, and care during transport, if the patient must be evacuated. The HMF is currently under development by NASA at the Johnson Space Center in Houston, Texas. Because of its specialized function, the HMF is being designed primarily by a team of NASA physicians, biomedical engineers, and other allied health professionals. In building the HMF, current off-the-shelf equipment will be used as much as possible. However, existing technology must be adapted in order to operate in microgravity and conform to space station weight and size constraints. The KC-135 provides a testing environment for equipment and procedures to be used in space. Using a parabolic flight path, the KC-135 can simulate weightlessness for a few valuable seconds. Here, a prototype of the patient restraint system is analyzed. This piece of equipment must be both flexible and portable. On space station, it will be used as a stretcher, a treatment area, a dental chair, and an x-ray table. The health maintenance facility has been divided into flight subsystems as well as ground support. These subsystems are similar to the medical services found in a large hospital. For example, the HMF will be designed to provide emergency medical care for injuries. Medical life support with patient monitoring capabilities, respiratory support, intravenous or IV fluid and nutritional support, a variety of physicians' instruments, imaging for diagnostics and therapeutic procedures, a clinical laboratory to provide tests and analysis in areas such as microbiology, a pharmacy containing necessary medications and a computerized inventory control system, central supply and a hyperbaric facility for treatment of decompression sickness. Although each of these capabilities will be needed on the space station, it isn't feasible to launch a large hospital facility into orbit. As a result, the entire health maintenance facility, with its preventive, diagnostic and therapeutic capabilities, must be designed to fit into a very limited space. In a hospital, a large staff of highly trained professionals provides health care services. The space station will not have those resources. Because of limited medical personnel, the HMF equipment will be user-friendly and easily maintained. In order to provide maximum flexibility, the HMF will have a modular design. Each piece of equipment will be self-contained and will be held in standard space station equipment racks. This modular design will allow the components to be switched out easily for repairs or to be upgraded as new technology becomes available. The patient restraint system, which provides the treatment area, will be located in front of the racks and will be stowed when not in use. Preventive health care is another major objective of the HMF. Exercise protocols will be designed to meet the individual needs of each crew member. In addition to providing a cardiovascular workout, these protocols will be used to help prevent the detrimental effects of weightlessness on bone and muscle. Exercise sessions will also generate physiological data for later analysis by NASA scientists. Here, a computerized video system is being developed for use with the exercise equipment. This system is designed to motivate the crew member and monitor the progress of the workout. Another piece of equipment currently being studied is a bicycle, which converts to a rower. This machine will provide a cardiovascular workout with the added feature of offering a choice of exercise activities. Unlike a hospital with its mounds of forms and stacks of paper, the HMF will use the space station's computer resources to integrate all the information from each subsystem. Dr. James Logan, manager of the Medical Sciences Space Station office at the Johnson Space Center, explains this innovative approach. One of the things that we're developing at Johnson Space Center is a concept known as the Medical Information Bus, or MIB. The MIB would enable all the medical devices on the health maintenance facility to not only interact with each other, but also interact with the HMF computer. Additional things that would be housed in the health maintenance facility computer would be things like diagnostic and treatment protocols or inventory management for the HMF. Another aspect would be the crew performance data, especially as it related to the exercise devices. If there was an illness on board the space station, after the crew medical officer did a diagnostic physical exam, he would enter the results of that physical exam on a keyboard, which would put those results in an electronic medical record. However, all the laboratory data and the radiographic data and the electrophysiologic data, such as an electrocardiogram, would automatically be entered into an electronic medical record. This is the Mission Control Center in Houston, Texas. This is the nerve center for the entire mission. The flight director and all the flight controllers stay in this room throughout the duration of the mission. This is also where the mission surgeon sits. After the crew medical officer on the space station gathers all the medical data, and the data is collated by the medical information bus, that information is downlinked to the earth and reconstructed at this console here in Mission Control. When the information is reconstructed, the mission surgeon has to make several key decisions. The first decision he or she would have to make is whether or not to activate a group of consultants, which would be other physicians and surgeons located all across the country, to have them actually look at the data with him or her. The next decision that the doctor would have to make is whether or not the medical condition can be treated definitively with the HMF onboard the space station or whether a rescue needs to be even considered. It becomes obvious then when you consider the mission and the cost of medical rescue that one of the prime goals of having a health maintenance facility onboard the space station is to be able to treat as many medical conditions as possible in flight without having a rescue. Here on earth, the development of a health maintenance facility may alter some current concepts for medical care. The key to the HMF concept is the ability to combine existing equipment with computer technology. This integrated package of health care resources can be used to assist in the diagnosis and management of medical problems which occur in remote environments, such as isolated rural communities. Also, the medical information bus can improve the quality of care in areas such as a hospital intensive care unit by integrating the information gathered from all the monitoring equipment. The medical information bus will simplify the various equipment connections and eliminate most of the paperwork burden. This will allow the care providers more time to spend in direct patient care. On previous space flights there was nothing comparable to the HMF. During those missions, the need for in-flight health care was not as great as it will be on space station. In order to successfully live and work on the space station, crew members will have to maintain their health without relying on frequent rescues. The space station health maintenance facility, the HMF, will be an important step in understanding the intricacy of the human body as it answers the challenge of living in space.