mobilization and exercise

define mobilization

therapeutic and prescriptive application of low workload activity

what is the goal of mobilization?

1. improve or maintain oxygen transport

2. perform in the upright position when possible to receive benefits of gravitational stress

define physical activity

bodily movement produced by muscle contraction that increases energy expenditure substantially over the resting state; not generally structured or goal oriented

define exercise

a form of PA that is planned, structured, and repetitive; typically requires at least moderate physical exertion, such that RR and HR are noticeably accelerated, especially when performed to develop or maintain fitness

define training

- systematic application of progressive exercise stimulus to elicit specific physiological, functional, or skill-based goals

- involves long-term planning and goals

- requires consistency and progression for effectiveness

define functional fitness

an individual's ability to perform work required for their day to day instrumental, work, and leisure tasks

how can exercise tests serve as standardized outcome measures?

- repeated at set intervals to measure change from baseline (avoid ceiling effect)

- performed in tandem w/ physiologic measurement

mobilization/exercise increase the ________ load. what is the significance of this for ill pts?

metabolic

--> load may already be elevated b/c of the current illness/treatment (acutely ill pts may be hypermetabolic)

what is the "safety margin" PTs should ensure when prescribing exercise for acutely ill pts?

- demand for oxygen should not exceed the available supply or delivery (monitor closely)

- be mindful of cumulative effect of multiple interventions

- pts w/ reduced O2 transport capacity are especially at risk

what factors contribute to increased metabolic demand and O2 consumption?

1. pathophysiological factors

2. intervention-related factors

3. psychosocial factors

4. miscellaneous

what does cellular respiration depend on?

the integrity of the cardiopulmonary unit (combining CHO & fats with O2 to make ATP)

what allows healthy individuals to meet oxygen needs when there's an increase in workload? how does this differ in hypermetabolic pts?

- in healthy individuals, at least 4x more O2 is delivered to tissues than is needed, allows individuals to meet needs when there's an increase in workload

- safety margin is reduced during hypermetabolic state and when pts have reduced O2 transport capacity

what is the benefit of HIIT exercise (anaerobic) on increasing aerobic capacity?

- increases anaerobic threshold

- allows individuals with severely compromised aerobic systems to produce ATP longer through anaerobic mechanisms

what must pts be able to manage during anaerobic training? what does this require?

- must be able to manage pH changes w/ anaerobic training

- requires adequate kidney, CV, and pulmonary function (start slow)

when does acid start to accumulate during exercise?

around 55% VO2 max

what is the significance of CV and pulmonary dysfunction in the O2 transport pathway?

- can lead to dysfunction in 1 or more steps in the O2 transport pathway

- but b/c of the interdependence b/t these steps and the ability to compensate, gross measures of gas exchange and oxygenation can appear normal

what determines the impairment of O2 transport and the degree of impairment in gross measures of O2 transport?

the number of steps in the O2 transport pathway affected by pathology and the severity

To maximize the capacity of the O2 transport pathway, the O2 transport system must be exposed to what two principal stressors?

1. gravitational stress

2. exercise stress

what do gravitational stress and exercise stress enhance?

both enhance the biochemical, physical, and mechanical efficiency of the O2 transport pathway and pts capacity to rapidly respond to changes in the physical environment

what should prescription of mobilization and exercise be based on?

- clinical presentation

- functional needs

- exercise test(s)

- pt goals

- PLOF

what are additional challenges with exercise prescription in acutely ill pts?

amount of time pts spend recumbent (in bed) and restricted mobility (d/t physical impairments and environmental barriers)

what is an oxidative stressor contributing to aging (worse when combined with smoking and a Western-type diet)?

disuse deconditioning

about half of the physical decline associated with aging has been attributed to:

lack of physical activity

what is restricted mobility on older adults associated with?

clinical depression

what is "prehabilitation"?

PA and exercise prior to surgery/hospital admission to speed recovery, minimize hospital stay, reduce complications, and decrease time to return to activities

what should PTs use to return pts to physiologic positions as soon as possible during acute hospitalization for illness?

PTs should utilize bolsters, adjustable beds, supportive chairs

how should preventative exercise be dosed?

aim for the dose that will maintain pts conditioning level and prevent deterioration

what is the primary means of countering orthostatic changes associated with recumbency?

upright position (exercise may have a limited role)

recumbent exercise CANNOT be used as a substitute for ______ associated with an upright position

gravitational stress

how does bedrest adversely effect most organ systems? why is this clinically important?

- by means of down-regulation of the O2 transport system

- clinically important because in conventional pt management, there is a direct relationship between how sick the pt is and the amount of time spent confined to bed

does cardiopulmonary or MSK function decline faster with prolonged bedrest?

cardiopulmonary function

what are potential consequences of bedrest?

1. fluid volume redistribution

2. muscular inactivity

3. altered distribution of body weight and pressure

4. aerobic deconditioning

5. other: catabolism, anorexia, paralytic ileus, constipation, etc.

what is the primary effect of mobilization and exercise on the CV and pulmonary systems?

- enhanced mucociliary transport and airway clearance

- minimize pooling/stagnation of bronchial secretions

what does CV deconditioning from bedrest include?

- loss of fluid volume

- loss of pressure regulating mechanisms

- loss of plasma volume

- diuresis

why is risk of DVT/thromboemboli increased with bedrest? what can exacerbate this?

- d/t increased hematocrit

- exacerbated by increases in blood viscosity, platelet count, platelet stickiness, plasma fibrinogen, and stasis of venous blood flow

how does bedrest reduce FRC? what does this lead to?

1. decrease in thoracic volume

2. increase in thoracic blood volume

--> both lead to increased pulmonary venous engorgement

what is closing volume (CV)?

volume of air in the lungs at which the small airways begin to close during expiration

what does an increased closing volume contribute to?

contributes to arterial desaturation and subsequent complications

With bed rest, blood vessels in _______ and ________ dilate

muscles and splanchnic circulation

pooling blood in the extremities when pt assumes the upright position may cause pts to feel:

lightheaded or dizzy and may faint - OH and resting tachycardia

what does muscle weakness attributed to bedrest lead to?

- discoordination, balance issues, poor posture

- muscle stiffness and soreness

- disuse osteoporosis and bone demineralization

- skin breakdown

which muscle fibers atrophy first with bedrest?

type I fibers

what can an increased renal load (diuresis) from bedrest lead to?

- electrolyte imbalances

- arrhythmias

- muscle cramping

- confusion

what are neurological changes associated with bedrest?

1. blunted baroreceptor responses

2. slowed electrical activity in the brain

3. emotional/behavioral changes

4. sleep disturbances

5. altered mental status

6. diminished sympathetic activity

what are metabolic effects of bedrest?

- glucose intolerance

- reduced insulin sensitivity

- increased calcium excretion

- increased nitrogen excretion (muscle loss)

what are immunological effects of bedrest?

- reduced cytokines and antibodies

- reduced lymph flow

what are alternatives to bedrest?

1. redesigned furniture and beds

2. lifting and transfer devices

3. tilt tables

what is exercise and mobilization prescription based on?

1. pt h/x

2. h/x of current illness and pt stability

3. assessment (chart review and physical exam)

4. lab results

5. diagnostic test results

6. imaging

7. pt goals

8. PLOF

9. baseline performance

what should be be done during and after exercise/mobilization?

During exercise: monitor closely and adjust intensity, duration, mode, work/rest interval as indicated

After exercise: continue to monitor, cooldown, address any non-urgent concerns

what are examples of mobilization stimuli?

ambulation

standing

transferring

ADLs

dangling

cycle ergometry

cycle ergometry in bed

turning in bed

bed exercises

what are examples of mobilization aids for the pt vs the PT?

for pt:

walking aids

weights

pulleys

monkey bar

grab bars

grab rope

portable oxygen

portable ventilator

for PT:

transfer belts

mechanical lifts for pts

how should you prepare for mobilization?

1. pt should be physically prepared

2. pts medication schedule should be reviewed

3. any equipment should be noted and positioned appropriately

4. movement procedures and techniques should be discussed with the team before implementation

what are physiological reactions to appropriate mobilization intensity?

1. optimal tidal volume

2. increased RR

3. increased air flow rates

4. enhanced mucociliary transport

5. cough stimulation

what are qualitative assessments for monitoring exercise?

1. pts response compared with resting baseline measures

2. quality and immediacy of the response

3. characteristics of quality of response

4. does the response commensurate with the intensity of exercise stimulus?

5. with cessation of exercise, do the responses revert to baseline? how fast?

6. do the variables return to baseline or remain higher than baseline?

what are commonly used monitoring variables?

HR

ECG

BP

RPP

RR

perceived exertion

breathlessness

discomfort/pain

fatigue