In this work, a postural change long-term care bed is developed that enables good-quality sleep and natural movement in rolling over, along with a specially designed mattress, in order to ensure comfortable sleep for long-term care receivers requiring assistance in rolling over in bed, and for families and other caregivers. Here, we provide an outline of the bed, and report on the “12-segment bottom and the ‘Gatch and roll' function” developed to achieve automatic postural change. We also report on measurements and evaluations related to body pressure, one of the causes of pressure sores.

Sanyo Electric has developed the “hist” postural change long-term care bed, which is equipped with a “Gatch and roll” mechanism for maintaining natural posture while turning over. There were two main goals in developing this device: to lighten the burden on long-term caregivers who must provide their patients with assistance in turning over in bed at night, and to contribute to more comfortable sleep for those patients. In this research, we conducted tests to verify the effectiveness of the “Gatch and roll” method as compared to conventional simple roll methods. The tests,conducted on two healthy subjects, incorporated measurements of both physiological values (such as EEG, EMG of the jaw, and EOG) and subjective reports. We proposed a new sleep evaluation method-n-M.A.R.-which focuses on how long light sleep and deep sleep continue and how clearly sleep cycles are defined, and calculates the rate of movement during n minutes of sleep at a given depth. Test results based on the n-M.A.R. method suggest that compared to simple roll methods,the Gatch and roll method is particularly effective in securing deep sleep and stable sleep rhythms. The action of turning over during sleep and the posture taken during this action are thought to dramatically affect the quality of sleep. The Gatch and roll method, which achieves both of these goals, can be considered an effective means of improving the quality of sleep for long-term care patients, in comparison to conventional simple roll methods.