Chapter 2: Homeostasis and adaptive responses to stressors

stressors

factors which create change in the body or environment, affect the basic physiological processes within the body, anything that causes stress

• can be short term or long term

types of stressors

1. physioloical

2. psychological

physiological processes

the normal things your body does to keep you alive and functioning

stress response

occurs when a person’s status is altered due to a reaction to a stressor (complex reactions by the body to any stressor)

Hans Selye (1946)

defined a stress model known as the General Adaptation Syndrome (GAS) or “fight or flight” in 1946

general adaptation syndrome (GAS model)

states that the body’s response to stress occurs in 3 predictable stages in an effort to maintain the body’s homeostasis (model represents a generalized response to a stressor that can be modified in specific situations)

homeostasis

a relative constancy in the internal environment of the body

3 stages in GAS

1. alarm stage

2. resistance stage

3. exhaustation stage

alarm stage

1. upon encountering a stressor, body reacts with “fight or flight” response

2. stress system is activated by internal or external stressor

3. adrenal gland release catecholamines, which act to combat stress and maintain homeostasis (balance)

4. catecholamines effect various body systems

5. resistance to additional stressors would be reduced @ this time, body focuses on one main stressor

catecholamines effect on body systems

1. increase HR = increase in blood to muscles, heart, etc

2. causes liver to convert glycogen to glucose = increase energy to body

3. decrease digestive system activity = decrease hunger

4. increase BP

5. dilates bronchioles = increase ventilation = increase oxygen in brain = weighted awareness

resistance stage

1. HPA axis

2. catecholamines stay elevated and body systems operate @ peak performance

3. result of catecholamines = increase in HR, increase in BP, increase in breathing, decrease in digestive activity

4. glycogen (stored form of glucose in liver) undergoes glycogeneolysis = increase supply of glucose

5. body remains on high alert

6. as resistance stage continues, body begins to experience fatigue, irritability and decreased concentration

HPA axis

hypothalamus sends hormone signal to the pituitary; then pituitary signals adrenal cortex to produce corticosteroids which participate in resistance response

exhaustion stage

1. if unrelieved = stressors will continue to adversely impact the body, until it is unable to respond further or is damaged by increased demands

2. persistent / unchecked activity of stress system depletes energy reserves and compromises the immune system

3. phase exhausts adrenal gland function, decreases in serum glucose production = decrease in energy availability

4. exhaustion leads to an overall decrease in tolerance to stress = onset of illness / physical collapse

contribution of stress

stressor may cause negative effect on body if body’s way of coping with stressor isn’t sufficient and diseases and disorders can result

relationship between stress and diseases

1. acute problem may develop during stress response or as an after effect of relieved stress

2. result in prolonged vasoconstriction = tissue inflammation and necrosis (ex stomatitis)

3. response can aggravate a pre existing condition causing an acute exacerbation (worsening of original disease)

4. response may be precipitating factor for relapse of chronic condition (ex. HSV)

5. stress response can develop cancerous process

6. stress can be etiologic causative agent in development of disease

protect body from stress

1. rest + good diet

2. exercise

3. counseling / therapy

4. biofeedback therapy (relaxation technique with music and art)

5. anti anxiety meds

According to hans selye’s GAS model, which are stages of the stress response?

1. alarm stage

2. resistance stage

3. exhaustion stage

which process occurs in the liver during the body’s response to stress?

glycogen is converted to glucose

during the stress response, which anatomical structure releases catecholamines?

adrenal glands

A patient is observed to be in the resistance stage of the stress response. Which clinical manifestations will most likely manifest?

1. increased heart rate

2. increased respiratory rate

3. increase blood pressure

A patient who has undergone a stressful event is physically and emotionally tired and unable to cope. Which stage of the stress response is being described by this scenario?

exhaustion stage

gastrointestinal system

stress related disorders: peptic ulcer disease, gastric stress ulcers, ulcerative colitis, nausea, diarrhea, cirrhosis due to alcohol abuse, stomatitis

nervous system

stress related disorders: multiple sclerosis, seizure disorder, depression, CVA/stroke

respiratory system

asthma

musculoskeletal system

rheumatoid arthritis

cardiovascular system

hypertension, angina, heart failure

skin

herpes simplex, eczema, acne

urinary system

acute renal failure

other systems

cancer, opportunistic infection, autoimmune disorders, obesity, PTSD

which complication could the patient with a prolonged vasoconstriction related to stress response present with?

stomatitis (stomach ulcer)

which statement is true regarding the effects of stress on the body?

stress may cause an exacerbation of a chronic condition, such as seizure disorder

which effect does stress have on the urinary system that contributes to renal failure?

1. tubular necrosis

2. damage to the nephron

3. decreased blood supply to the kidneys

which statements are accurate regarding prolonged stress and the rile it plays in wound healing?

1. protein synthesis is decreased

2. scar size and thickness are increased

3. nutrients delivered to the wound are increased

which strategies should be employed as coping mechanisms for a patient who deals with high levels of daily stress?

1. ensuring adequate rest

2. consuming a healthy diet

3. participating in counseling

4. engaging in biofeedback therapy

which manifestations would be associated with the later phase of the resistance stage of the stress response?

1. fatigue

2. irritability

3. decreased concentration

which physiologic responses occur during the exhaustion stage of the stress response?

1. physical collapse

2. energy reserves become depleted

3. the immune system is compromised

which descriptor represents the activity level in the digestive system in response to stress?

decreases; during the stress response, digestive activity decreases in order to divert blood flow to critical organs and body systems

arrange the steps in the alarm stage of the stress response in correct order

1. stressor activates the sympathetic nervous system (SNS)

2. the hypothalamus activates the adrenal glands

3. catecholamines are released

4. the heart, liver, and digestive systems are affected (HR increases, glycogen is converted to glucose, digestive system activity decreases)

5. resistance to additional stressors are reduced

which respiratory system symptom occurs during the alarm stage of the stress response

dilation of bronchioles

which statements are accurate regarding the effects of stress on disease process?

1. stress may result in the development of chronic medical conditions

2. an acute medical condition can be precipitated by a stressful event

which is an accurate description of the rationale for the development of gastric stress ulcers, which are precipitated by prolonged stress?

decreased gastric mobility

which stress related disorder develops specifically in response to suppression of immune function

infection; prolonged or severe stress may cause ea decrease in the immune system resulting in an infection

which are considered behavioral therapies that can be encouraged for patients experiencing stress on a daily basis?

1. art therapy

2. music therapy

3. imagery therapy

which manifestations would be expected in a patient diagnosed with post traumatic stress disorder

onset of a dissociative state and lack of responsiveness