respiratory pharma Flashcards
respiratory treatements (9)
- high flow oxygen
- beta agonist drugs
- Anticholinergic drugs
- corticosteriods
- adreneline
- CPAP
- SaO2 and cardiac monitoring
- severe cases: sedation, intubation, mechaniacl ventilation
-antibiotics or chemotheraputics
Oxygen as treatment
- Hypoxia is primary casue of death from exacerbation, oxygen may help to decrease dyspnoea, aid bronchodilation and minimose risk of arrythima
- Should be used in patients where O2 sat below 92% in room air, weane off ehrn sat level exceeds 94%
sympathomimetics
agonists at beta 2 adrenergic receptors on bronchiole smooth muscle
sympathomimetics examples
- salbutomol: ventolin
- salmeterol
- trebutaline
mechanism of B2 agonists on bronchiole muscle cells
-drug binds to B2 receptor
- adenylate cyclase activated
- increase cAMP concentration
- activation of protein kinase enzyme which attaches phosphate groups to other protiens
- myosin-light chained kinase enzyme is inactivated
- reduced interaction of actin and myosin -> smooth muscle relaxation and bronchodilation
anticholineric drugs are used in…
moderate to severe cases
best used in combination with other therapies
- can be used in acute asthma, maintenence asthma and COPD
anticholinergic drugs action
blocks musinaric acetylcholine receptos on bronchiole smooth muscle
smooth muscle bronchodilates
corticosteroids
these drugs switch on/off specific genes that code for proteins involved in the inflammatory process or its regulation
- can take hours to exert full therapeutic effect
corticosteriod examples
hydrocortisone- IV for asthma
methylprednisilone
predisnisone
steriod recommendations
- used in moderate to severe cases
- decrease admission and relapse if given in first hour od exacerbation
- oral steriods are most convinents, least expensive
- IV given to patients that dont respond to oral
methylxanthines
used for ashtma nd COPD
work by 2 mechainisms
- inhibition of enzyme phosphodiesterase
- block adenosine type 1 receptors that inhibit adenylate cyclase
=bronchodilation
CPAP
-applies continuous positive airway pressure to keep airways open through breathing cycle
sympathomimetics role
used to increase or decrease cardiac contractility
sympathomimetics example
beta blockers
beta blockers are a type of:
sympathomimetics
beta blockers example
metoprolol, propanolol
mechainsm of beta blockers
- cmpetitvely block beta 1 adrenic receptors in the SA and AV nodes od heart and ventricular muscles
- reduce heart rate and contractility, therefore reduce cardiac output and blood pressure
- becasue HR decreases, more time for blood to move from aorta to other areas if circulation
- aortic blood pressure therefore reaches lower levels during diastole so afterload is decreased
advantages of beta blockers (3)
- reduction in rate and force of contraction, reduced cardiac output and BP
- decreases myocardial workload and oxygen consumption
- proven over 30 years to reduce Bp and incidence od fatal and non-fatal stroke
disadvanatges of beta blockers
- fatigue/depression
- vivid or bad dreams
- cold peripheries
-possible conduction block or heart failure - may increase serum triglycerides
- casue asthma due to bronchoconstriction
calcium channel blocker is a tpye of….
vasodilator
calcium channel blocker examples
nifedipine, felodipine
Verapamil is…
is a calcium channel blocker which binds more to calcium channels on cardiac muscle and pacemaker cells so may be more useful in treatinf one arrthymias
calcium channel blockers function
- Vascular smooth muscle cells have only small amonuts of stored calcium ions, calcium ions are nessecary for muscle contraction because they permit interaction bectween actin and myosin
- Calcium ions enter through voltage gated calcium channels where the muscle cell is depoalrised
- Blocking these channels in vascular smooth muscle casues less calcium to be avaliable intracellulary so the force of the contration is decreases -> vasodialtion and reduced TPR
calcium channel blockers unwanted effects
excessive vasodialtion, hypotension, dizziness, flushing, ankle oedema, calcium channel blockers may also worsen heart block and heart failure
proton pump inhibitor examples
Omezaprole, pantoprazole and other prazole medicatrions
what are proton pump inhibitors
- drugs that affect proton pimp inhibitors in stomach wall
- most potent inhibitors in GI tract
omezaprole function
-irreversibly inbibits the HKTpase in stomach - final step int he acid scretory pathway
- reduces acid secretion by 99%
- is neutral pH byt because it is a weak base, it accumulates in the caniculi of parietal cells where it is activated and has specific action on these cells
unwated effects of omezaprole
are uncommon but may include;
headache, diarhea, rashes, dizziness, pain in muscles and joints