The Effects of Immobility Flashcards
The Effects of Immobility
Mobility refers to a person’s ability to move about freely, and immobility
refers to the inability to do so.
Bed rest is an intervention that restricts patients to bed for therapeutic
reasons and is sometimes prescribed for selected patients. The therapeutic
reasons for bed rest include decreasing the oxygen needs of the body, reducing
cardiac workload and pain, and allowing a debilitated patient to rest. Bed rest
has many different interpretations among health care professionals. The
duration of bed rest depends on the illness or injury and a patient’s prior state
of health. The effects of muscular deconditioning associated with lack of physical
activity are often apparent in a maer of days. The individual of average
weight and height without a chronic illness on bed rest loses muscle strength
from baseline levels at a rate of 3% a day (McCance and Huether, 2017).
Vulnerable populations, such as older adults, are especially at risk for loss of
function during acute illness and hospitalization (Wald et al., 2019). Immobility
also is associated with cardiovascular, skeletal, and other organ changes. The
term disuse atrophy describes the tendency of cells and tissue to reduce in size
and function in response to prolonged inactivity resulting from bed rest,
trauma, casting of a body part, or local nerve damage. The greater the extent and the longer the duration of immobility, the more
pronounced the consequences. The patient with complete mobility restrictions
is continually at risk for the hazards of immobility. When possible, it is imperative that patients, especially older adults, have limited bed rest and that
their activity is more than bed to chair. Loss of walking independence increases
hospital stays, need for rehabilitation services, or nursing home placement. In
addition, the deconditioning related to reduced walking increases the risk for
patient falls
Metabolic Changes (systemic effect)
Changes in mobility alter endocrine metabolism, calcium resorption, and
functioning of the gastrointestinal (GI) system. When injury or stress occurs, the endocrine system triggers a series of
responses aimed at maintaining blood pressure and preserving life. It is
important in maintaining homeostasis. Tissues and cells live in an internal
environment that the endocrine system helps regulate through maintenance of
sodium, potassium, water, and acid-base balance. It also regulates energy
metabolism. Thyroid hormone increases the basal metabolic rate (BMR), and
energy becomes available to cells through the integrated action of GI and
pancreatic hormones. Immobility disrupts normal metabolic processes, decreasing the metabolic
rate; altering the metabolism of carbohydrates, fats, and proteins; causing fluid,
electrolyte, and calcium imbalances; and causing GI disturbances such as
decreased appetite and slowing of peristalsis. However, in the presence of an
infectious process, immobilized patients often have an increased BMR as a
result of fever or wound healing because these increase cellular oxygen
requirements. When the patient is immobile, his or her body often
excretes more nitrogen (the end product of amino acid breakdown) than it
ingests in proteins, resulting in negative nitrogen balance. Weight loss,
decreased muscle mass, and weakness result from tissue catabolism (tissue
breakdown). Another metabolic change associated with immobility is calcium resorption
(loss) from bones. Immobility causes the release of calcium into the circulation.
Normally the kidneys excrete the excess calcium. However, if they are unable
to respond appropriately, hypercalcemia results. Pathological fractures may
occur if calcium resorption continues as a patient remains on bed rest or
continues to be immobile.Impairments of GI functioning caused by decreased mobility vary. Difficulty
in passing stools (constipation) is a common symptom. A condition known as
pseudodiarrhea often results from a fecal impaction (accumulation of hardened
feces). This finding is not normal diarrhea, but rather liquid stool passing
around the area of fecal impaction (see Chapter 47). Left untreated, fecal
impaction results in a mechanical bowel obstruction that partly or completely
occludes the intestinal lumen, blocking normal propulsion of liquid and gas.
The resulting fluid in the intestine produces distention and increases
intraluminal pressure. Over time intestinal function becomes depressed,
dehydration occurs, absorption ceases, and fluid and electrolyte disturbances
worsen.
Respiratory Changes (systemic effect)
Lack of movement and exercise places patients at risk for respiratory
complications. Patients who are immobile are at high risk for developing
pulmonary atelectasis (collapse of alveoli) and hypostatic pneumonia
(inflammation of the lung from stasis or pooling of secretions). Both decreased
oxygenation and prolonged recovery add to patients’ discomfort (Lewis et al.,
2017). In atelectasis secretions block a bronchiole or a bronchus, and the distal
lung tissue (alveoli) collapses as the existing air is absorbed, producing
hypoventilation. Ultimately the distribution of mucus in
the bronchi increases, particularly when the patient is in the supine, prone, or
lateral position. Mucus accumulates in the dependent regions of the airways
(Fig. 39.1). Hypostatic pneumonia frequently results because mucus is an
excellent place for bacteria to grow.
Cardiovascular Changes (systemic effect)
Immobilization also affects the cardiovascular system, frequently resulting in
orthostatic hypotension, increased cardiac workload, and thrombus formation.
Orthostatic hypotension is a drop in systolic pressure by at least 20 mm Hg or
a drop in diastolic pressure by at least 10 mm Hg within 3 minutes of rising to
an upright position (Shibao et al., 2013; Ball et al., 2019). Patients also
experience symptoms of dizziness, light-headedness, nausea, tachycardia,
pallor, or fainting when changing from the supine to standing position. In immobilised patient decreased circulating fluid volume, pooling of blood in the lower extremities, and decreased autonomic response occur. As the workload of the heart increases, so does its oxygen consumption.
Therefore the heart works harder and less efficiently during periods of
prolonged rest. As immobilization increases, cardiac output falls, further
decreasing cardiac efficiency and increasing workload. Patients who are immobile are also at risk for thrombus formation. A
thrombus is an accumulation of platelets, fibrin, cloing factors, and the
cellular elements of the blood aached to the interior wall of a vein or artery,
which sometimes occludes the lumen of the vessel (Fig. 39.2). Three factors
contribute to venous thrombus formation: (1) damage to the vessel wall (e.g.,
injury during surgical procedures), (2) alterations of blood flow (e.g., slow
blood flow in calf veins associated with bed rest), and (3) alterations in blood
constituents (e.g., a change in cloing factors or increased platelet activity).
These three factors are often referred to as Virchow’s triad (McCance and
Huether, 2017). As a nurse you will practice in numerous situations in which
deep vein thrombosis (DVT) must be prevented, especially during
perioperative care.
Musculoskeletal Changes (systemic effect)
Immobility causes permanent or temporary impairment of musculoskeletal
structures. Because of protein breakdown, a patient loses lean body mass
during immobility. The reduced muscle mass makes it difficult for patients to
sustain activity without increased fatigue. If immobility continues and the
patient does not exercise, there is further loss of muscle mass. Prolonged
immobility often leads to disuse atrophy. Loss of endurance, decreased muscle
mass and strength, and joint instability place patients at risk for falls. Immobilization also causes two skeletal changes: impaired calcium
metabolism and joint abnormalities. Because immobilization results in bone
resorption, the bone tissue is less dense or atrophied, and disuse osteoporosis
results. When disuse osteoporosis occurs, a patient is at risk for pathological
fractures. Immobility can lead to joint contractures. A joint contracture is an abnormal
and possibly permanent condition characterized by fixation of a joint. It is
important to note that flexor muscles for joints are stronger than extensor
muscles and therefore contribute to the formation of contractures. Disuse,
atrophy, and shortening of the muscle fibers cause joint contractures. When a
contracture occurs, the joint cannot achieve full ROM. Contractures sometimes
leave a joint or joints in a nonfunctional position, as seen in patients who are
permanently curled in a fetal position. Early prevention of contractures is
essential. One common and debilitating contracture is footdrop (Fig. 39.3). When
footdrop occurs, the foot is permanently fixed in plantar flexion. Ambulation is
difficult with the foot in this position because the patient cannot dorsiflex the
foot. A patient with footdrop is unable to lift the toes off the ground and is at
risk of stumbling. Patients who have had CVAs with resulting right- or leftsided
paralysis (hemiplegia) are at risk for footdrop.
Urinary Elimination Changes (systemic effect)
Immobility alters a patient’s urinary elimination. In the upright position urine
flows out of the renal pelvis and into the ureters and bladder because of
gravitational forces. When a patient is recumbent or flat, the kidneys and
ureters move toward a more level plane. Urine formed by the kidney needs to
enter the bladder unaided by gravity. Because the peristaltic contractions of the
ureters are insufficient to overcome gravity, the renal pelvis fills before urine
enters the ureters. This condition is called urinary stasis and increases the risk
of urinary tract infection (UTI) and renal calculi (see Chapter 46). Renal calculi
are calcium stones that lodge in the renal pelvis or pass through the ureters.
Immobilized patients are at risk for calculi because they frequently have
hypercalcemia.As the period of immobility continues, fluid intake often diminishes. When
combined with other problems such as fever, the risk for dehydration
increases. As a result, urinary output declines on or about the fifth or sixth day
after immobilization, and the urine becomes concentrated. Concentrated urine
increases the risk for calculi formation and infection. Another cause of UTI in
immobilized patients is the use of an indwelling urinary catheter
Integumentary Changes (systemic effect)
The changes in metabolism that accompany immobility add to the harmful
effect of pressure on the skin in immobilized patients. This makes immobility a
major risk factor for pressure injuries. Any break in the integrity of the skin is
difficult to heal. A pressure injury is an impairment of the skin as a result of prolonged
ischemia (decreased blood supply) in tissues (see Chapter 48). It is
characterized initially by inflammation and usually forms over a bony
prominence. Ischemia develops when the pressure on the skin is greater than
the pressure inside the small peripheral blood vessels supplying blood to the
skin. Tissue metabolism depends on the supply of oxygen and nutrients to and
the elimination of metabolic wastes from the blood. Pressure affects cellular
metabolism by decreasing or totally eliminating tissue circulation. When a
patient lies in bed or sits in a chair, the weight of the body is on bony
prominences. The longer the pressure is applied, the longer is the period of
ischemia and therefore the greater the risk of skin breakdown (Stephens et al.,
2018). The prevalence of pressure injuries is highest in long-term care facilities,
whereas hospital-acquired pressure injuries are the highest in adult intensive
care units
Psychosocial Effects
Immobilization often leads to emotional and behavioral responses, sensory
alterations, and changes in coping. Illnesses that result in limited or impaired
mobility can cause social isolation and loneliness (Musich et al., 2018). Every
patient responds to immobility differently.
Patients with restricted mobility may have some depression. Depression is
an affective disorder characterized by exaggerated feelings of sadness,
melancholy, dejection, worthlessness, emptiness, and hopelessness out of
proportion to reality. It results from worrying about present and future levels
of health, finances, and family needs. Because immobilization removes a
patient from a daily routine, he or she has more time to worry about disability.
Worrying quickly increases a patient’s depression, causing withdrawal.
Withdrawn patients often do not want to participate in their own care.
