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• stress and adaptation :

  • used in psychology

  • refers to consequence of failure of an organism to respond appropriately

  • signs of stress may be cognitive , emotional , physical
• Activity tolerance and fatigue

  • physical activity - process of energy expenditure for the purpose of accomplishing an effect

  • rest-inactivity

  • fatigue - lack of sufficient energy
• stress response: homeostasis

  purposeful maintenance of a stable internal environment

  condition of equilibrium in body internal environment

  psychologic processes opposing change

  • dynamic condition

  • narrow range is compatible with maintaining life
• Stress :

  anything that disrupts equilibrium or demands that exceed the body’s ability to cope.

  require psychological , behavioural and physiological adjustment

  can have negative health consequences

  state manifested by symptoms that arise from the coordinated activation of the neuroendocrine and immune systems
• Adaptation:

  ability to respond to challenges of physical or psychological homeostasis and to return to a balanced state
• Stressors :

  events or environmental agents responsible for stress response

  BE ENDOGENOUS OR EXOGENOUS / MIX
• stress types :

  eustress : an stress that is healthy, gives one a feeling of fulfilment or other positive feelings

  distress :

  aversive state in which an animal is unable to adapt completely to stressors and their resulting stress and shows maladaptive behaviours
• stages of general adaptation syndrome:

  -alarm stage

  -resistance stage

  -exhaustion stage
• stage of general adaptation syndrome

  Alarm stage :

  generalised stimulation of the sympathetic nervous system and the HPA axis resulting in release of catecholamines and cortisol
• stage of general adaptation syndrome:

  Resistance stage :

  body selects the most effective and economical channels of defence
• stage of general adaptation syndrome :

  exhaustion stage:

  resources are depleted and signs of wear and tear appear
• Allostasis :

  physiological changes in the neruoendorcrine , autonomic and immune system that occur in response to real or perceived challenges to homeostasis
• Neuroendocrine responses :

  stress response is strongly influenced by the nervous (sympathetic) and endocrine system

  • Mobilisation of energy

  • Sharpened focus and awareness

  • Increased cerebral blood flow and glucose usage

  • Enhanced cardio/respiratory function

  • Redistribution of blood from to brain and muscles

  • Modulation of immune response

  • Inhibition of reproductive function

  • Decrease appetite
• Hormone response to stress :

  Corticotropin-Releasing Factor

  Found in hypothalamus, limbic system and brain stem

  Important in ANS activity, adrenal activity, metabolism and behaviour

  Induces the secretion of ACTH which stimulates adrenal gland to secrete glucocorticoid hormones (e.g. cortisol)

  Other important hormone responses to stress

  About 10+ other hormones
• ADAPTATION TO STRESS

  • mechanisms that evolved for organisms to respond to or modify their environments , habits

  • feedback mechanisms

  • negative feedback
• ADAPTIVE CAPACITY

  • stressors tend to produce different responses in different persons or in same person at different times

  -internal

  -external

  • relative risk for development of stress-related pathologic process is partially dependent on these factors
• factors affecting ability to adapt :

  -previous learning /exposure and physiologic reserve

  -time

  -internal:genetic endowment

  -health status

  -nutrition

  -hardiness
• failure to adapt:

  -emotional disturbances

  -headaches

  -insomia

  -upset stomach

  -Rheumatic disorders
• general adpatation syndrome :

  alarm phase=hormone stage - may be stopped at any stage - resistance phase =further hormone release - exhaustation phase =maladaptive changes
• management of stress :

  -treat the cause

  -symptom management

  -counselling

  -exercise

  -anxiolytics
• Effects of chronic stress

  • Pathophysiologic changes occur

  • Altered physiological function

  • Component of a system fails

  • Neural and hormonal connections fail

  • Overwhelms ability of system to respond: overactive or underactive

  • Chronic activation of the stress response can result in illness and long term heath problems
• Chronic stress has been linked to other disorders

  • cardiovascular , gastrointestinal , immune , oral disease, delays in wound healing

  • altered psychological factors

  • depression , accidents, suicide
• reactions to acute stress:

  • Associated with fight or flight

  • Facilitation of neural pathways mediating

  • Arousal

  •Alertness

  • Vigilance

  • Cognition

  • Focused attention

  • Appropriate aggression
• results from phsiologically or physiologically threatening events

  may be life-saving

  • divert blood away from less essential areas

  • enable rapid processing of information

  in a healthy person : redirect attention from behaviours that promote health

  In unhealthy people : can lead to arrhythmias and health prblems
• treatment for stress:

  Helping people avoid coping behaviours that impose a risk to health

  • Providing people with alternative stress-reducing strategies

  • Purposeful priority setting and problem solving

  • Nonpharmacologic methods of stress reduction
• Nonpharmacologic methods of stress reduction

  • Relaxation techniques

  • Guided imagery

  • Music therapy

  • Massage

  • Biofeedback
• activity intolerance and fatigue:

  • activity intolerance : not having sufficient physical or psychological energy reserve to endure or complete an activity

  • fatigue : depletion of reserves that makes it impossible to complete activity

  — normal

  — symptomatic
• FACTORS USED TO DETERMINE DIAGNOSIS OF FATIGUE

  Fatigue is not just tiredness

  • Tiredness is relieved by a good sleep

  • Fatigue persists

  Can be described in terms of Underlying physiologic basis

  • Origin or cause

  • Temporal patterns over time
• Physiologic basis of fatigue :

  Diaphragmatic and motor mechanisms

  • Force and duration of muscle work exceeds muscle energy stores

  • Neurologic mechanisms

  • Involve the loss of maximal capacity to generate force during exercise
• fatigue origins:

  -pathologic

  treatment-related causes

  -unknown causes

  chronic fatigue syndrome

  -physiologic

  environmental factors

  drug-related incidents

  physical exertion
• chronic fatigue:

  • present for 50% of the day or lasting 1-6 months or longer

  • more common in people with chronic health problems
• acute fatigue :

  rapid onset and lasting less than 4 weeks

  • often defined as fatigue associated with increased activity that is carried out to the point of exhaustion
• chronic fatigue syndrome:

  Disabling fatigue greater than 6 months duration not relieved by rest

  significant reduction in activities

  exclusionary diagnosis

  • active medical condition explaining fatigue

  • past or current diagnosis of major depressive disorder

  • alcohol or other substance
• CFS : criteria

  Presence of at least four of following symptoms:

  • Impaired memory or concentration

  • Sore throat

  • Tender cervical or axillary lymph nodes

  • Muscle pain • Multiple joint pain

  • New headaches

  • Unrefreshing sleep

  • Postexertional malaise
• CFS treatment:

  • focus on management , rather cure

  • education

  • emotional support

  • treatment of symptoms
• CFS manifestations:

  physical problems:

  • complaint of fatigue

  • low-grade fever

  • palpable and tender cervical lymph nodes

  • wheezing

  psychological problems

  • impaired cognition

  • mood and sleep disturbances

  • balance problems

  • anxiety / depression
• immobility and rest complications:

  defy the active use of skeletal muscles , movement against gravity , conservation of body fluid, maintenance of cardiopulmonary reserves

  • generalised weakness

  • atelectasis

  • pneumonia

  • pulmonarry emboli

  • muscular atrophy

  • constipation

  • impaired sensory perception
• interventional treatment of immobility-related degeneration:

  Should address physical and psychosocial needs

  Goals of care:

  • Decrease risk for complications

  • Provision of diversional activities to offset sensory deprivation

  • Repositional schedule

  • Prophylactic DVT intervention
• Physiologic effects of immobility and bed rest:

  
• physiologic effects of immobility and bed rest: