Immobility and Deconditioning Flashcards
A small study from 2008 of healthy adults who had 10 days of bed rest found what?
lost about 10% function in different measures of strength, fitness and flexibility.
What equation could be used to roughly calculate % decline in VO2 per day of bed rest?
decline in %VO2max = (1.4 to .85) X (#of days bed rest)
Things that have a functional decline during hospitalization?
Functional decline is the leading complication of hospitalization for the elderly (occurs in 34-50% of hospitalized older adults)
Deconditioning and functional decline was found to occur by day 2 of hospitalization
Comparison of functional status at baseline and day 2 in 71 hospitalized pts >age 74 showed declining ability in: mobility, transfer, toileting, feeding, and grooming.
This leads to previously independent patients requiring post-acute care (e.g.: SNF; IRF; LTACH; home care)
Slide about how Functional decline may not improve.
Older people who develop new functional deficits during hospitalization are less likely to recover lost function.
One study: 1279 older adults (>70yrs) hospitalized for acute medical illness.
31% had decline in ADLs at discharge compared with pre-admission baseline.
At 3 months, 51% of original study sample reported new ADL/IADL disabilities (40%) compared with pre-admission, and 11% had died.
What were some conclusions from the 1966 Dallas bed rest study?
~25% decline in cardiac output. post- bedrest HR is higher b/c of ↓ stroke volume. ↓ plasma volume, ↑ blood viscosity. All declines from bed rest are reversible with exercise. Looking at same men 30 years later seems to show that 3 weeks of bed rest is worse than 30 years of aging.
How deconditioning affects the cardiovascular system?
Cardiac output decreases
Stroke volume decreases
resting HR increases –> limits HR reserve
Decreased plasma volume
Orthostatic hypotension
* these changes result in reduced CV reserve and predispose pt to progressive disability.
What are the neurologic adaptations to bedrest?
↓ parasympathetic activity, ↑sympathetic activity
bed rest gives hyper norepinephrine output
How does % composition of type I and type II muscle fibers change with bed rest?
↑ % type II muscle fibers
↓ % type I muscle fibers
decrease in total muscle mass
Bone adaptations to bed rest / deconditioning?
↓ bone mineral density (BMD) esp. weight bearing bones (calcaneus has huge density loss)
↑ Ca++ –> hypercalcemia
↑ fracture risk
What are some rough % declines in strength per day of bed rest?
Immobilization decreases strength by 1.0%–1.5%/day (he didn’t have reference for this commonly cited value)
Strength can decrease as much as 20%–30 % during only a week to nine days of bedrest.
Other muscle/ bone concerns of bed rest / deconditioning?
Shortening of muscle and of connective tissue around joints ↑ contracture; ↑ risk of Hypertrophic Ossificans
Loss of bone mineral density. ↑ osteopenia/porosis
pulmonary changes to bed rest / deconditioning?
-Diaphragm moves cephalad when supine.
-decrease in the thoracic volume.
-Respiratory rate increases.
Tidal volume, minute volume, and maximal breathing capacity all decrease.
What condition can result from the pulmonary changes resulting from bed rest?
atelectasis and O2 desaturation, and may contribute to development of pneumonia.
integumentary changes from bedrest?
A pressure ulcer, or decubitus ulcer, is the consequence of ischemia and anoxia to tissue.
Tissues are compressed, blood vessels are compressed and blood flow is diverted by continual pressure on the skin and underlying structures
Cellular respiration is impaired and cells die
Which skin areas are commonly affected by prone bed rest?
face, side of face, breast (sternal angle?), ASIS, upper thigh, knee, dorsal toe surface.
