Respiratory system Flashcards
list antihistamines (H1- receptor antagonists) (4)
chlorphenamine
certirizine
loratidine
fexofenadine
common indications for antihistamines (3)?
- first line for allergies (particularly hay fever)
- aid relief of pruritus (itchiness) and urticaria (hives)
- adjunctive Tx in anaphylaxis following adrenaline
MOA of antihistamines?
antagonists of the H1 receptor blocking effects of excess histamine
what is the difference between first and second generation antihistamines?
first generation- cause sedation
(chlorphenamine)
second generation- non sedative
(loratidine, cetirizine, fexofenadine)
why do newer second generation antihistamines not exert a sedative effect?
they do not cross the BBB
sedating antihistamines (chlorphenamine) should be avoided in which pt group?
severe liver disease as may precipitate hepatic encephalopathy
list drugs belonging to the antimuscarinic class (bronhcodilators) (4)?
ipatropium
tiotropium
glycopyrronium
aclidinium
common indications for antimuscarinics (2)?
- COPD
- Asthma
MOA of antimuscarinics?
bind to muscarinic receptors competitively inhibiting acetylcholine
blocks parasympathetic effect- reduce smooth muscle tone and reeduce secretions in the RT
common adverse effects (respiratory) of antimuscarinics (3)?
nasopharyngitis
sinusitis
cough
antimuscarinics should be used with caution in which pt groups (3)?
angle-closure glaucoma (can precipitate rise in IOP)
those with or at risk of arrhythmias
urinary retention
how can you communicate antimuscarinics to the pt?
Tx to open up the airways and improve their breathing
monitoring of antimuscarinics (resp)?
ask patients about their symtpoms and review peak flow
should check their inhaler technique
list common B2-agonists (5)
salbutamol
terbutaline
salmeterol
formoterol
indacaterol
common indications for B2-agonists (3)?
- asthma
- COPD
- hyperkalaemia
where are B2-receptors found?
smooth muscle of the bronchi gut, uterus and blood vessels
stimulation of B2-receptors has what effect on smooth muscle?
smooth muscle relaxation
like insulin what effect do B2-agonists have on potassium?
stimulate Na+/K+ (ATPase) pumps causing shift of K+ from the extracellular to intracellular compartment
long acting B2 agonists can have what side effect due to a rise in serum lactate levels?
muscle cramps
LABAs should lonly be used in asthma if what other drug is also being prescribed?
Inhaled Corticosteroid (ICS)
(without LABAs are assoc with inc in asthma deaths)
B2 agonists should be prescribed with care in which pt group due to risk of angina or arrhythmias?
cardiovascular disease
Tachycardia may provoke angina/arrhythmia
give the common preparation of B2 agonists prescribed for the following indications 1) as reuired for asthma
2) asthma/COPD exacerbation
3) maintainence of asthma
1) SABA- inhaled
2) nebulised therapy
3) combi inhaler to ensure co-admin with steroid
what does MDI stand for when refering to drugs delivered in aerosol such as B2 agonists?
MDI- metered dose inhaler
how could you communicate the action of B2 agonists to the patient?
treatment is to help their airways relax and improve their breathing
*treats their symtpoms not the disease
how should pts taking B2 agonists be monitored?
symtpom severity/ exacerbations
when prescribing nebuliser therapy which of air or oxygen should be used in 1) asthma and 2) COPD?
1) oxygen in asthma
2) medical air in COPD (risk of CO2 retention)
name corticosteroids (inhaled) (3)
beclometasone
budesonide
fluticasone
common indications for inhaled corticosteroids (2)?
1) asthma
2) COPD
MOA of inhaled corticosteroids?
reduces mucosal inflammation, widens the airways and reduces mucous secretion by modififying gene transcription:
pro-inflammatory/ cytokines are downregulated
antiinflammatory proteins are upregulated
common adverse effects of inhlaed corticosteroids? (3)
oral candidiasis (thrush)
hoarse voice
v little absorbed into blood so few systmeic adverse effects unless taken at very high dose
high dose inhaled corticosteroids should be used with caution in which pt groups? (2)
1) COPD pts with history of pneumonia
2) children where there is potential fro growth suppression
how could you communicate the action of inhaled corticosteroids to the pt?
offering a steroid inhaler to ‘dampen down’ inflammation in the lung
(advise them to rinse mouth/gargle after taking it to help prevent sore mouth/ hoarse voice)
how should inhaled corticosteroids be monitored?
symptom severity
review after 3-6months to see if therapy should be maintained/ reduced/ intensified
which of asthma/COPD is more responsive to inhaled corticosteroids and why?
Asthma- poorly controlled airway inflammation can lead to remodelling and fixed airflow obstruction, as inflammation is generally steroid responsive pts should be encouraged to take steroid to prevent disease progression
montelukast is what kind of drug?
leukotriene receptor antagonist
common indications for montelukast by pt age group (3)?
1) adults add on for asthma when ICS/LABA not adequate
2) 5-12yr olds- alternative to LABAs as add on therapy where ICS in insufficeint
3) <5yrs first line preventative when unable to take ICS
MOA of montelukast?
leukotrienes (produced by mast cells and eosinophils) activate G protein coupled leukotriene receptor CysLT1 activating pathwasy in inflammation and bronchiconstriction
Montelukast blocks CysLT1 receptor reducing inflammation and bronchoconstriction in asthma dampening down inflammatory cascade
common adverse effects of montelukast?
headache
abdo pain
URTI
when should montelukast be prescribed?
only when asthma is incompletely controlled with ICS and LABAs
who can prescribe montelukast?
those with the appropriate knwoledge in the management of asthma as they are a third line therapy
how is montelukast taken?
orally as a tablet, chewable tablet or granule form
how could you communicate the action of montelukast to the pt?
helps to reduce inflammation and relax their airways to hopefullt improve their symptoms and control their disease
common indications for oxygen therapy (3)?
1) to increase tissue oxygen delivery in acute hypoxaemia
2) accelerate reabsorption of pleural gas in pneumothorax
3) reduce carboxyhaemoglobin half-life in CO poisoning
oxygen should be given with care in which pt group?
chronic type 2 resp failure (severe COPD)
can results in rise in PaCO2 leading to resp acidosis, depressed consciousness and worsened tissue hypoxia
what is the target SpO2 in 1) most pts 2) those with Type 2 resp failure?
1) 94-98%
2) 88-92%
what should the conc and flow of oxygen be in venturi and in nasal cannulae?
Venturi: 60-80%, high flow 15L/m
Nasal cannulae: 24-50% 2-6L/m
common indications for sildenafil?
- erectile dysfunction
- Primary pulmonary hypertension
what typ of drug is sildenafil?
phosphodiesterase (type 5) inhibitor
what type of drug is sildenafil?
Phosphodiesterase (type 5) inhibitor
finish PDE-5 pg 190
