stress Flashcards
what are the three definitions of stress?
- To emphasise certain words in speech
- A force applied to a body causing deformation or strain
- Emotional or mental pressure
what are the two categories within stressors?
- physical
- threats
what are examples of physical stressors?
- injury/surgery
- infection/shock
- pain
- exposure to cold
- sustained exercise
what are examples of threat stressors?
- imprisonment/torture
- exams
which body systems are involved in stress?
- nervous
- endocrine
- immune
what does the effect of stress depend on?
- duration and severity of the stressor
- effectiveness of any responses
what are the stages in stress?
- alarm reaction
- resistance phase
- exhaustion phase
what is involved in the alarm reaction stage of stress?
- acute stress response
- fight flight or fright response
- physiological effects
what is involved in the resistance phase of stress?
- adapting to the stressor
what is involved in the exhaustion phase of stress?
- severe persistent stress
- responses futile, systems fail
- pathological effects
what are the sequence of the stages in stress called?
general adaptation syndrome
is stress bad?
- a little stress can be good
what are the components in the alarm reaction?
- sympathetic ns
- adrenal glands
adrenaline (adrenal medulla)
corticosteroids (adrenal cortex)
describe the neural component (SNS) in the alarm reaction
- increased cardiac output
- redistribution of cardiac output (increased flow to muscle, decreased flow to gut/kidney)
- glycogen broken down to glucose
- mobilisation of fat stores
- stimulation of adrenaline release
when would there be an exhaustion stage?
persistent stress
what is the action of adrenaline in the alarm reaction?
- secreted by adrenal medulla
- releases augments and prolongs action of sympathetic nerves
- increases cardiac output
- redistribution of cardiac output
- metabolic effects
what is the action of glucocorticoids in the alarm reaction?
- secreted by adrenal cortex
- (steroid eg cortisol)
- actions complement those of sympathetic ns and adrenaline
what is the main stress hormone?
cortisol
where is glucocorticoids released from?
adrenal cortex
where is adrenaline released from?
adrenal medulla
what are the actions of cortisol?
- metabolic
increased energy production from glucose, aa and fats
increased protein breakdown - enhances adrenaline action
- anti-inflammatory
- immunosupression
describe glucocorticoid action on immune response
- Glucocorticoids have anti-inflammatory and immunosuppressant actions
- They can inhibit release of prostaglandins and leukotrienes
- They inhibit macrophages and helper T lymphocytes
- Many patients receive corticosteroid drug therapy
- Increased incidence of illness at times of stress
what is an example of a condition which can be treated with corticosteroids as anti-inflammatory drugs?
arthritis
what is the effect of the long term use of corticosteroids?
- disrupt normal control mechanisms
- suppresses corticotrophin releasing hormone and adrenocorticotrophic hormone release, so natural stress response is supressed
what controls the release of cortisol?
hypothalamic-pituitary- adrenal axis
what is stress analgesia?
pain is diminished during physical stress due to the release of endogenous opioid peptides, endorphins, enkephalins in CNS which suppress nociception and pain
stress for patients in dentistry
- Stress evident in anticipation of treatment
- Oral Surgery > scaling
- Effects greater in anxious patients and even greater in ‘dental phobics’
- Pain increases the amount of stress
- Local anaesthesia is stressful
- Noise of dental instruments (e.g. drills) can contribute to the stress
- Masks and gowns add to the stress
- Individuals vary in their responses to a stimulus or circumstances
- The anticipatory response differs in men and women
- Women have higher HR responses, but this varies with the type of treatment
- There are no significant differences in BP responses in men and women
- Stress responses tend to be greater in children than in adults
stress in dentists
- Oral surgery: tooth extraction:
Increased HR, BP - Effects are greater:
When standing
With complex/difficult procedures
With anxious patients
When supervising a student’s first extraction
what are the two possible outcomes of persistent stress?
- adaptation phase (cope)
- exhaustion phase (don’t cope)
what happens in the adaptation phase?
- an individual’s stress response diminishes with persistent exposure to stressor
- The individual has ‘adapted’
- The stressor is no longer a ‘threat’
- The individual has become ‘resistant’ to the stressors
- This generally happens if the individual’s responses are effective in removing the stressor (or its perceived threat)
what happens to individuals who fail to adapt to the stressors?
- exhaustion phase
- leads to
adrenal failure
immunosupression
peptic ulcers
CVS disease - death can occur in extreme cases
what is the difference between type A/B people?
type A - competetive, driven individuals prone to high bp
type B- relaxed individuals
