Cardiac Flashcards
If Mrs Smith is administered a second drug that is known to inhibit the metabolism of propranolol, what effect would this have on bioavailability and what are potential clinical consequences
The addition of a drug that inhibits propranolol metabolism will significantly affect bioavailability due to reduction in clearance resulting in increase systematic blood concentration. A dose adjustment is required
Clinical consequences = worsening plasma concentration leads to bradycardia, hypotension’s, palpating worsening HF
If the prescriber was to discontinue propranolol for any reason, how should this be done?
Beta blockers should not be withdrawn suddenly for any reason. Rapid withdrawal can result in rebound effect due to unpregulation of adrenergic receptors
Consequences may be exacerbated of hypertension, angina, dis rhythmic or MI
Dose should be reduced over 1-2 weeks
Identify the common indications for use of Digoxin
Heart failure, arrhythmias
List common ADRs and interventions for digoxin
Nausea - take with food
Dizzy, weak, tired, confused - care with driving
Allergic reaction - skin rashes, itching, swelling, difficulty breathing
Palpations - let GP know
Vomiting diarrhoea, blurred vision - may be digoxin toxicity, contact GP urgently
What are common drug interactions that impact on digoxin
Diuretics - alter electrolyte balance
Potassium depleting drugs - increase risk of digoxin toxicity
Calcium channel blockers enhance plasma concentration of digoxin
What must nurses so before administering Digoxin and why
Must check apical pulse prior to administering and checking rate and rhythm, monitor potassium levels
What are contraindications for Digoxin ?
Acute MI
Hypersensitivity to drug
Ventricular fibrillation
Digoxin has a very narrow therapeutic index and a very long half life, what are the possible clinical indications of this?
Long half life - takes. time to achieve steady state
Narrow therapeutic index - need to monitor for digoxin toxicity and potassium levels
You will need to explain Digoxin toxicity, how it happens, signs and symptoms and treatments
Results in dysrhythmia/tachycardia, GI symptoms of nausea, vomiting, diarrhoea, CNS symptoms confusion and visual symptoms
Risk factors
- dehydration - alter electrolyte balance
- hypokalaemia - potassium competes with digoxin for binding Na+/K+ enhancing the effect
- Renal failure
treatment - Digibind
What is the MOA of Digoxin
Inhibits Na+/K+ pump which induces an increase in intracellular sodium that will drive an influx of calcium in the heart and cause an increase in contractility
Identify common indications for nitrates (GTN spray)
To prevent or treats stable angina, unstable angina and heart failure associates with acute MI
Most commonly used to prevent angina
Patient education for Nitrates (GTN spray)
Tolerance - develops over time with continued stimulation of nitrate receptors= desensitised effects of GTN, increase dose =same effect
Angina action plan - ‘take 1 spray, 5 mins if still present take another’
Always carry spray/tabs
Only take when needed
Common drug interactions with GTN spray
Other substance that may also cause vasodilation my enhance the orthostatic hypotensive effects e.g alcohol, antihypertensives, treatment for erectile dysfunction
Common ADRs for GTN spray
Postural hypotension, dizziness, fainting, headache, nausea, vomiting, dry mouth, blurred vision, facial flushing, tachycardia
What is the MOA of GTN spray
Binds to nitrate receptors in vascular smooth muscles - relaxation causing Venodilation and Vasodilation of arteries increasing coronary perfusion, increase oxygen delivery to myocardium
Generic drug names for nitrates
GTN spray - sublingual spray, tab, patch , IV
Isosorbide tab and sublingual tab
Name generic drugs of Ace inhibitors
Enalapril
Quinapril
Cilizapril
(any other drug ending in pril)
What should be monitored when taking Ace inhibitors
Monitor BP and renal function
What are some common ADRs for Ace inhibitors?
headache, nausea, dizziness, weakness, hypotension, loss of taste, rash ,fever, joint pain
Dry persistent cough
Rare but potentially fatal - angio-oedema
List any common drug interactions with Ace inhibitors
Diuretics - ACE causes hyperkalaemia = K+ retention, check renal function and electrolytes
Lithium - decrease excretion of lithium which may result in lithium toxicity, check levels and renal function
NSAIDS - increase risk of hyperkalaemia and decrease effect of ACE
Contraindications / precautions of ACE inhibitors
Avoid use in person with ACEi hypersensitivity, hx of angio-oedema, hyperkalaemia, renal impairment
Avoid use in pregnancy
Patient education with Enalapril
Info on ADRs
Monitor BP
Not to take over the counter NSAIDS
Dietary advice K+ rich foods to avoid
Common indications for Enlapril
Hypertension, heart failure, left ventricular dysfunction following MI
Diabetic nephropathy
What is the MOA of Enalapril
Blocks the enzyme required for converting angitension 1 to 2 resulting in decreased vascular tone
What is the MOA of Aspirin
Inhibits COX1 which inhibits platelet aggregation and vasoconstriction Aspirin binds to the platelet for the life of the platelet
What is a common indication for Aspirin
Prevention of arterial thrombosis