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COMMON SIGNS AND SYMPTOMS OF STRESS

TABLE 5-3

PHYSICAL EMOTIONAL COGNITIVE Rapid heart rate

Rapid breathing Increased blood

pressure Difficulty falling

asleep or excessive sleep Loss of appetite

or excessive eating Stiff muscles Hyperactivity or

inactivity Dry mouth Constipation or

diarrhea Lack of interest

in sex

Irritability Angry outbursts Hypercritical Verbal abuse Withdrawal Depression

Impaired attention and concentration Forgetfulness Preoccupation Poor judgment

64 U N I T 2 Integrating Basic Concepts

decreases, the releasing gland is stimulated. In positive feedback, the opposite occurs, keeping concentrations of hormones within a stable range at all times. Homeosta- sis is maintained when hormones are released as needed or inhibited when adequate.

As long as demands on the central nervous, autonomic nervous, and endocrine systems are within adaptive capac- ity, the body maintains homeostasis. When internal or external changes overwhelm homeostatic adaptation,

the stressor, (2) number of stressors, (3) duration of the stressor, (4) physical health status, (5) life experiences, (6) coping strategies, (7) social support, (8) personal beliefs, (9) attitudes, and (10) values. Because of unique differences, outcomes may be adaptive or maladaptive depending on each person’s response.

Physiologic Stress Response

Hans Selye, a Canadian physician who lived in the early 1900s, devoted much of his life to researching the collec- tive physiologic processes of the stress response, which he called the general adaptation syndrome. Selye observed that this syndrome occurs repeatedly and consistently regardless of the nature of the stressor. He maintained that (1) the body’s physical response is always the same, and (2) it follows a one-, two-, or three-stage pattern: alarm stage, stage of resistance, and in some cases, stage of ex- haustion (Fig. 5-7). The first two stages parallel the adap- tation processes of maintaining homeostasis (discussed earlier). Therefore, brief stress responses generally have adaptive outcomes, with restoration of equilibrium. If the stage of resistance is prolonged, however, the process can become maladaptive and pathologic. It can lead to stress-related disorders and, in some cases, death.

Alarm Stage

At the immediate onset of a stress response, storage vesi- cles within sympathetic nervous system neurons rapidly release norepinephrine. Shortly thereafter, the adrenal glands secrete additional norepinephrine and epinephrine.

These stimulating neurotransmitters and neurohormones prepare the person for a “fight or flight” response. Almost simultaneously, the hypothalamus releases corticotropin- releasing factor (CRF), which triggers the pituitary gland to secrete adrenocorticotropic hormone (ACTH). The result is the release of cortisol, a stress hormone, from the adrenal cortex.

Cortisol plays various important roles in responding to a stressor such as raising blood glucose as a reserve for meeting increased energy requirements (Table 5-4). Pro- longed elevation of levels of norepinephrine, epinephrine, and cortisol, however, can predispose clients to stress- related disorders (discussed later).

Stage of Resistance

The stage of resistance is characterized by restoration to normalcy. Neuroendocrine hormones, although temporar- ily excessive, endeavor to compensate for the physiologic changes of the alarm stage. The usual outcome is a return to homeostasis. If stress is protracted, however, resistance efforts remain activated. Consequently one or more organs or physiologic processes may lead eventually to increased vulnerability for stress-related disorders or progression to the stage of exhaustion.

Stage of Exhaustion

Physiologic exhaustion occurs when one or more adap- tive or resistive mechanisms can no longer protect the person experiencing a stressor. Once beneficial mecha- nisms now become destructive. For example, the effects of stress-related neurohormones suppress the immune

FIGURE 5-7

Stages of the general adaptation syndrome.

C H A P T E R 5 Homeostasis, Adaptation, and Stress 65

66 U N I T 2 Integrating Basic Concepts

system. As a result, there are reduced natural killer (NK) cells, which attack viruses and cancer cells, and decreased secretory immunoglobulin A (sIgA), an anti- body involved in immune defense. These changes put the person at risk for frequent or severe infections or cancer. Additional disruptions to other organs include reduced beneficial bowel microorganisms and increased bowel pathogens (Kelly, 1999). As resistance dwindles, there is physical and mental deterioration, illness, and death.

Coping Mechanisms

Sigmund Freud posited that humans use coping mechanisms

(unconscious tactics to defend the psyche) to prevent their ego, or reality base, from feeling inadequate (Table 5-5).

These manipulations of reality act as psychological first aid, allowing people to avoid temporarily the emotional effects of stress. When appropriate and moderate, coping mechanisms enable people to maintain their mental equi- librium. Coping mechanisms that are overused or over- extended may have maladaptive effects, distorting reality to such an extent that the person fails to recognize and cor- rect his or her weaknesses. Consequently the person may avoid taking responsibility for solving personal problems.

Coping Strategies

Coping strategies(stress-reduction activities selected con- sciously) help people to deal with stress-provoking events or situations. They can be therapeutic and nontherapeutic.

Therapeutic coping strategies usually help the person to acquire insight, gain confidence to confront reality, and develop emotional maturity. Examples include seeking professional assistance in a crisis, using problem-solving techniques, demonstrating assertive behavior, practic- ing progressive relaxation, and turning to a comforting other or higher power.

Maladaptation results when people use nontherapeutic coping strategies such as mind- and mood-altering sub- stances, hostility and aggression, excessive sleep, avoid- ance of conflict, and abandonment of social activities.

Negative coping strategies may provide immediate tem- porary relief from a stressor, but they eventually cause problems.

ACTIONS OR CORTISOL

TABLE 5-4

MAJOR INFLUENCE EFFECT ON BODY

Glucose metabolism Protein metabolism Fat metabolism Anti-inflammatory

action

Psychic effect Adaptive effect

Stimulates gluconeogenesis (synthesis of glucose from amino acids and sources other than carbohydrates) Decreases glucose use by the tissues

Increases breakdown of proteins Increases plasma protein levels

Increases mobilization and use of fatty acids

Stabilizes membranes of inflamed cells, preventing release of proinflammatory mediators Decreases capillary permeability to prevent swelling of tissues

Depresses phagocytosis by white blood cells Suppresses the immune response

Causes atrophy of lymphoid tissue

Reduces eosinophils, white blood cells active during infectious and allergic reactions Decreases cell-mediated immunity

Reduces fever

Inhibits fibroblasts, connective tissue cells that promote wound healing May contribute to emotional instability

Facilitates the response of tissues to physiologic changes, such as increased norepinephrine, during trauma and extreme stress

Adapted from Porth, C. M. (2007). Essentials of pathophysiology: Concepts of altered health states(2nd ed.). Philadelphia:

Lippincott Williams & Wilkins, p. 692.

Stop • Think + Respond BOX 5-2 List the following stress-related responses in sequential order:

1. The adrenal cortex releases cortisol.

2. The pituitary gland secretes ACTH.

3. The body prepares for fight or flight.

4. The blood glucose level rises.

5. The adrenal glands release norepinephrine and epinephrine.

6. The hypothalamus secretes CRF.

7. The immune system becomes suppressed.

8. Sympathetic neurons release norepinephrine.

Psychological Stress Responses

Just as stress requires adaptation from the body, stress also affects the psyche (mind). The mind, in turn, mounts additional defenses.

arthritis and other connective tissue disorders; (2) failure to respond, as in immunosuppression; or (3) a weakened immune response, which may contribute to infections and cancer. Even psychological variables such as prolonged anger, feelings of helplessness, and worry can potentially influence the onset and progression of immune system–

mediated diseases (Cohen & Herbert, 1996; Godbout &

Glaser, 2006; Kuster & Merkle, 2004).

Nurses must be aware of potential stressors affecting clients because they add to the cumulative effect of other stressful life events. When a person is experiencing a stressor, nurses do one or several of the following:

• Identify the stressors.

• Assess the client’s response to stress.

• Eliminate or reduce the stressors.

• Prevent additional stressors.

• Promote the client’s physiologic adaptive responses.

• Support the client’s psychological coping strategies.

• Assist in maintaining a network of social support.

• Implement stress reduction and stress management techniques.

NURSING IMPLICATIONS

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