The relationship between bed rest and sitting orthostatic intolerance in adults residing in chronic care facilities

fox mt, sidani s & brooks d (2010) Journal of Nursing and Healthcare of Chronic Illness 2 , 187–196 The relationship between bed rest and sitting orthostatic intolerance in adults residing in chronic care facilities Aim. To examine the relationship between orthostatic intolerance and bed rest as it was used by/with 65 adults residing in chronic care facilities. Background. The evidence on the relationship between bed rest and orthostatic intolerance has been obtained from aerospace studies conducted in highly controlled laboratory settings, and is regarded as having high internal validity. In the studies, prolonged and continuous bed rest, administered in a horizontal or negative tilt body position, had a major effect on orthostatic intolerance in young adults. However, the applicability of the findings to the conditions of the real world of practice is questionable. Methods. Participants were recruited over the period of April 2005 to August 2006. A naturalistic cohort design was used. The cohorts represented different doses of bed rest that were naturally occurring. Comparisons were made between patients who had no bed rest (comparative dose group, n = 20), two to four days (moderate dose, n = 23) and five to seven days of bed rest (high dose, n = 22) during a one‐week monitoring period. Orthostatic intolerance was measured by orthostatic vital signs and a self‐report scale. Bed rest dose was measured by the total number of days spent in bed during one week . Results. Post hoc comparisons, using Bonferroni adjustments, indicated significant differences in adjusted means on self‐reported orthostatic intolerance between the comparative and high (CI: −4·12, −0·85; p < 0·001), and the moderate and high (CI: 0·35, 3·56, p < 0·01) bed rest dose cohorts. No group differences were found on orthostatic vital signs. Conclusions. A moderate dose of bed rest with intermittent exposure to upright posture may protect against subjective orthostatic intolerance in patients who are unable to tolerate being out of bed every day. Future research may examine the effects of reducing bed rest days on orthostatic intolerance in individuals with high doses of five to seven days of bed rest.