CVS Pharmacology Flashcards
Esmolol:
Is useful in the treatment of essential hypertension
False. It is only given intravenously and has a short half life.
Esmolol:
Has a half life of 2 minutes
False. It is around 10 minutes.
Esmolol:
Is largely excreted unchanged in the urine
False. It is rapidly metabolised by red-cell esterases.
Esmolol:
Acts selectively on beta-1 receptors
False. It is non-selective.
Esmolol:
Possesses intrinsic sympathomimetic activity
False
The following statements about selective phosphodiesterase (PDE) inhibitors are true:
Inhibition of isoenzyme family No. I effects a positive inotropic action
False. Inhibition of isoenzyme family No. III results in positive inotropy.
The following statements about selective phosphodiesterase (PDE) inhibitors are true:
Inhibition of isoenzyme family No. III results in clinically important bronchodilatation
False. Bronchodilatation does occur but not to a clinically significant degree.
The following statements about selective phosphodiesterase (PDE) inhibitors are true:
They increase myocardial oxygen consumption
False. There is unchanged or even slightly reduced myocardial oxygen consumption as systemic vasodilation reduces left ventricular systolic wall tension.
The following statements about selective phosphodiesterase (PDE) inhibitors are true:
Tachycardia is a common occurrence
True. There is a reflex tachycardia.
The following statements about selective phosphodiesterase (PDE) inhibitors are true:
Their use increases hblood pressure as a result of increased cardiac output and systemic vascular resistance.
False. Hypotension is often seen as a result of reduced systemic vascular resistance due to smooth muscle relaxation.
Milrinone:
Is one of the bipridine derivative group of phosphodiesterase inhibitors.
True. Enoximone and piroximone are imidazolone derivatives.
Milrinone:
Is structurally related to amrinone
False
Milrinone:
It’s short half life makes it well suited to use as an infusion
False. It is used in infusion form but has a terminal half life of 2.5 hours. A loading dose is required.
Milrinone:
Doses should be reduced in end stage renal failure
True. 80% is excreted unchanged via the kidneys and dose reductions are required when the creatinine clearance falls to less than 30 ml/min.
Milrinone:
Is incompatible with intravenous frusemide when given through the same cannula
True
Clonidine:
Is a selective partial agonist for the alpha-2 adrenoceptor with a ratio of approximately 200:1 (alpha2:alpha1)
True
Clonidine:
Is rapidly absorbed when given orally
True
Clonidine:
When given as premedication, it reduces the MAC by up to 50%
False. It does reduce MAC but only the highly selective drugs such as dexmedetomidine have lowered anaesthetic requirements to this degree.
Clonidine:
Discontinuation can result in hypertension
True. Rebound hypertension occurs on discontinuation of long term use.
Clonidine:
Has a diuretic effect in humans
True. It inhibits the release of ADH.
Ephedrine:
Is a catecholamine
False. It does not have a hydroxyl substitution of the benzene ring, and therefore cannot properly be called a catecholamine.
Ephedrine:
Causes the stimulation of both alpha and beta adrenoceptors
True
Ephedrine:
Acts directly and indirectly on adrenoceptors
True. It’s main effects are from the release of noradrenaline but it also has some direct effect on receptors.
Ephedrine:
Is a uterine relaxant
False. All anaesthetic vapours are uterine relaxants.
Ephedrine:
Can exist in four isomeric forms, two of which are pharmacologically active.
False. It can exist in four isomeric forms but the only active one is the l-form. Ephedrine is supplied as the racaemic mixture or simply in the l-form.
The following are indications for the use of ACE inhibitors:
Pre-eclampsia
False. ACE Inhibitors are contraindicated in pregnancy.
The following are indications for the use of ACE inhibitors:
Essential hypertension
True
The following are indications for the use of ACE inhibitors:
Hypertension secondary to bilateral renal artery stenosis
False. ACE Inhibitors are contraindicated in bilateral renal artery stenosis or unilateral renal artery stenosis supplying a single kidney as renal failure may supervene.
The following are indications for the use of ACE inhibitors:
Following acute myocardial infarction
True
The following are indications for the use of ACE inhibitors:
Chronic congestive cardiac failure
True
Regarding Digoxin:
25% of the oral dose is absorbed
False. It is well absorbed orally.
Regarding Digoxin:
95% is bound to plasma proteins
False. There is insignificant binding to plasma proteins.
Regarding Digoxin:
It is largely excreted unchanged in the urine
True
Regarding Digoxin:
Hypokalaemia may cause raised serum levels of digoxin
True
Regarding Digoxin:
Toxicity may result in Mobitz type II heart block
True. All forms of heart block have been recorded in digitalis toxicity
The following drugs cause prolongation of the Q-T interval:
Sotalol
True. Sotalol, a beta blocker, posesses class III activity, and both quinidine and disopyramide have class 1A actions with mild class III activity prolonging the cardiac action potential and hence the Q-T interval.
The following drugs cause prolongation of the Q-T interval:
Quinidine
True
The following drugs cause prolongation of the Q-T interval:
Verapamil
False
The following drugs cause prolongation of the Q-T interval:
Flecainide
False. Flecainide, a class IC antiarrhythmic agent does not directly prolong the Q-T interval.
The following drugs cause prolongation of the Q-T interval:
Disopyramide
True
The following drugs have potassium sparing diuretic effects:
Elanapril
True. The angiotensin converting enzyme inhibitors have an anti-aldosterone effect They act as weak potassium sparing diuretics and concomittant use of such drugs should be undertaken with care.
The following drugs have potassium sparing diuretic effects:
Furosemide
False. Frusemide use can result in hypokalaemia.
The following drugs have potassium sparing diuretic effects:
Triamterene
True
The following drugs have potassium sparing diuretic effects:
Spironolactone
True
The following drugs have potassium sparing diuretic effects:
Flecainide
False. It has no diuretic effect.
Sodium nitroprusside:
Acts by stimulating the release of nitric oxide in vascular tissue
True
Sodium nitroprusside:
Acts as an arteriolar and venous dilator
False
Sodium nitroprusside:
Is associated with a baroreceptor mediated rise in heart rate
True. Is associated with a reflex tachycardia.
Sodium nitroprusside:
Rapidy decomposes in the presence of light
False. Its decomposition is surprisingly slow: 50% of its activity remains after 2 days exposure to light.
Sodium nitroprusside:
Is broken down by non-specific plasma esterases
False. Breakdown occurs in red blood cells with production of cyanomethaemoglobin.
The following are recognised complications of amiodarone:
Peripheral neuropathy
True
The following are recognised complications of amiodarone:
Prologation of the Q-T interval
True
The following are recognised complications of amiodarone:
Hyperthyoidism
True. Hypo or hyper-thyroidism may occur at higher doses.
The following are recognised complications of amiodarone:
Reversible restrictive lung defect
True. Pulmonary fibrosis, if treated early and the amiodarone stopped, may regress.
The following are recognised complications of amiodarone:
Optic atrophy
False. Corneal microdeposits rather than optic atrophy occur in long term use.
The following Beta-blockers are metabolised predominantly by the liver:
Labetolol
True
The following Beta-blockers are metabolised predominantly by the liver:
Propranolol
True
The following Beta-blockers are metabolised predominantly by the liver:
Atenolol
False. Atenolol and sotalol are water soluble and therefore predominantly metabolised by the kidney.