Classifying signals from a wearable accelerometer device to measure respiratory rate.

BACKGROUND: Automatic measurement of respiratory rate in general hospital patients is difficult. Patient movement degrades the signal and variation of the breathing cycle means that accurate observation for ≥60 s is needed for adequate precision. METHODS: We studied acutely ill patients recently admitted to a teaching hospital. Breath duration was measured from a triaxial accelerometer attached to the chest wall and compared with a signal from a nasal cannula. We randomly divided the patient records into a training (n=54) and a test set (n=7). We used machine learning to train a neural network to select reliable signals, automatically identifying signal features associated with accurate measurement of respiratory rate. We used the test records to assess the accuracy of the device, indicated by the median absolute difference between respiratory rates, provided by the accelerometer and by the nasal cannula. RESULTS: In the test set of patients, machine classification of the respiratory signal reduced the median absolute difference (interquartile range) from 1.25 (0.56-2.18) to 0.48 (0.30-0.78) breaths per min. 50% of the recording periods were rejected as unreliable and in one patient, only 10% of the signal time was classified as reliable. However, even only 10% of observation time would allow accurate measurement for 6 min in an hour of recording, giving greater reliability than nurse charting, which is based on much less observation time. CONCLUSION: Signals from a body-mounted accelerometer yield accurate measures of respiratory rate, which could improve automatic illness scoring in adult hospital patients.

Health beliefs of rural Canadians: implications for practice.

OBJECTIVE: The objective of the present study was to examine the health beliefs, values and practices of rural residents living in two geographically diverse regions of western Canada. DESIGN: An ethnographic study with semistructured interviews of 55 persons was conducted with participants ranging in age from 19 to 84 years. RESULTS: Being healthy was described as having balance in one's life, taking into consideration the relationship between the physical, mental, social, and spiritual aspects of the person. Health-seeking behaviours spanned the gamut of diet, exercise, sleep, home remedies, a belief in a spiritual being, to consulting health professionals. Resources that participants valued included professionals who listened, friends, neighbours, church, music, elders, ambulance service and the internet. CONCLUSIONS: It is important that professionals view the person beyond the disease and take into account more than the physical manifestations of an illness. A key component is the demonstration of respect for all persons regardless of age. It is essential that health professionals develop websites providing accurate health-care information. Participants noted the need to recruit and retain professionals in rural regions.