Respiratory medications Flashcards
Sympathetic vs Parasympathetic responses. Explain and state what neurotransmitters they both use, as well as actions on the lungs and heart for both.
SNS - fight or flight
Noradrenaline & adrenaline
Lungs - bronchodilation
Heart - increased HR and contractile force
PNS rest and digest
Acetylcholine
Lungs - bronchoconstriction
Heart - decreased HR and contractile force
Bronchodilators also known as
Beta 2 agonists
Beta 2 agonist medications act by
and example
stimulating beta 2 receptors in the bronchial smooth muscle causing bronchodilation and inhibit mediator release from mast cells.
E.g salbutamol
Beta 1 receptors are located where? and what is the effect when they’re stimulated
Located on smooth muscle of the heart -
increase HR and contractility
Beta 2 receptors are located where? and what is the effect when they’re stimulated
located on smooth muscle of bronchioles, blood vessels supplying brain, heart, kidney and skeletal muscles, uterus, liver.
bronchodilation, vasodilation leading to increased blood supply to these areas and fine muscle tremors, uterine relaxation, glucose release
Why do you think the beta 2 agonists are ideally administered via the inhaled route?
Inhalation localizes the drug to the lung tissue, concentrating the therapeutic effect on the airway smooth muscles while minimizing the distribution of the drug to the systemic circulation
B2 agonists. What are the two types?
Short acting [SABA’s] and Long acting [LABA’s].
Describe the actions of SABA’s and LABA’s
SABA'S Provide relief for 4-6 hours Rapid onset of action 5-15mins Can be used in an acute asthma attack [PRN] E.g Salbutamol
LABA's Long acting [12hrs] Slow onset of action Not to be used to relieve acute symptoms give regularly E.g.Salmeterol
B2 agonists common ADR’s
Tachycardia, palpitations, headaches, restlessness, tremor
Cautions for use of SABA
FREQUENT use can result in
decreased B2 agonism = decreased bronchodilation
increased B1 stimulation, resulting in increased HR, anxiety and tremors
Cautions for use of LABA
Not to be used to treat acute asthma
Used in moderate to severe asthma and COPD
Anticholinergic Bronchodilators actions and classifications
Block the PNS stimulation of vagus nerve resulting in smooth muscle relaxation and bronchodilation.
SAMA and LAMA short acting and long acting muscarinic antagonists
Agonist vs antagonist
An agonist is a drug that binds to the receptor, producing a similar response to the intended chemical and receptor. Whereas an antagonist is a drug that binds to the receptor either on the primary site, or on another site, which all together stops the receptor from producing a response
Anticholinergic Bronchodilators common ADR’s
Dry mouth, nausea, metalic taste, constipation, headache
Preventers - inhaled corticosteroids [ICS]. MOA? mechanism of action
Mimic action of natural glucocorticoids, the stress hormones secreted from the adrenal gland.
Action in lungs Dec early+late stages of inflammatory response Dec bronchial mucosal inflammation Dec bronchial hyper-reactivity Inc responsiveness to b-agonists
E.g. fluticasone
Inhaled corticosteroids cautions - e.g. when recommended and pt education
Must be taken continuously [full effect may take weeks] and not stopped without consultation with prescriber
Given via inhalation with spacer greatly reduces systemic adverse effects
May reduce the rate of exacerbations in severe COPD.
Not recommended for mild to moderate COPD
Adverse effects of inhaled corticosteroids
Dysphonia
Oropharyngeal candidasis [oral thrush]
To minimize these effects, the pt should be taught to administer their medication via a spacer and to rinse mouth and throat after each dose to prevent thrush
Nursing factors to consider
Education points - inhaler technique, use of space and care of spacer, action plans for managing symptoms online, ADR’s for both inhalers and oral medications
Beta agonists action involves
dilation of airways
relief of bronchospasm
uterine relaxation
Leukotriene-receptors trigger all of these actions
Inflammation, bronchoconstriction, mucus production
Function of leukotriene receptors?
Leukotrienes are involved in asthmatic and allergic reactions and act to sustain inflammatory reactions.
Preventer medications used in the treatment of asthma include:
cromoglycate and zafirlukast
Side effects of beta agonists
increased HR, decreased BP, and restlessness
Which of these respiratory drug groups is used in the immediate relief of asthma?
Bronchodilators
Anticholinergic drugs block vagal tone. T/F
True
Salbutamol is a beta
agonist
Theophylline, a xanthine derivative, has variable pharmacokinetic parameters. T/F
T. Its variable pharmacokinetic parameter is one of the reasons for the decreasing clinical use.
Adverse drug reactions related to corticosteroids include
Pharyngeal irritation. Oral fungal infections. Coughing
Beta-adrenoceptor agonists cause all of the following
uterine relaxation, tremor, hyperglycaemia
corticosteroid examples
Fluticasone, Beclomethasone, Budesonide
Leukotriene receptor antagonists are used for
coughing, wheezing and SOB
The organ that is most susceptible to any disruption in oxygen supply is the
brain
Frequent use of salbutamol may diminish bronchodilation in the short term. T/F
True
