Hypertension Flashcards
Systemic blood pressure is regulated by what two systems of the body? Be specific.
(Sympathetic nervous system and the renin-angiotensin-aldosterone system)
Explain the mechanism by which the sympathetic nervous system controls blood pressure.
(When baroreceptors in blood vessels sense there is a decrease in blood pressure, catecholamines are released from the adrenals and those increased cardiac output and peripheral vascular resistance resulting in increased blood pressure)
What is released from the kidneys when there is decreased renal perfusion say in a case of CKD?
(Renin)
What other organ needs to be working in addition to the kidneys to produce angiotensin I?
(The liver, it needs to produce angiotensinogen which is then converted to angiotensin I by the renin produced by the kidneys)
What converts angiotensin I to angiotensin II and where is it produced?
(ACE and the lungs)
What effect does angiotensin II have on systemic vascular resistance and how does it produce that effect?
(It increases systemic vascular resistance by causing contraction of the smooth muscle in vasculature throughout the body)
How is angiotensin II related to an increase in blood volume and therefore cardiac output that is associated with the RAAS system and hypertension?
(Angiotensin II triggers the release of aldosterone from the adrenal glands which then triggers the kidneys to reabsorb sodium and water)
You’re presented with a cute little kitty that you want to get a blood pressure reading on, what method would you choose and how would you determine the appropriate cuff size?
(Doppler is preferred method in cats and small dogs, the width of your cuff should be 30-40% the circumference of the site you are choosing to use)
If you were taking the BP on a cat and you for some reason only had a size 5 cuff, you would expect the BP to be falsely high/low (choose).
(Low, cuff too big = falsely low, cuff too small = falsely high)
What are the most common causes of hypertension in cats?
(CKD and hyperthyroidism)
What are the more common causes of hypertension in dogs?
(Kidney dz (can be acute or chronic unlike cats which is typically CKD) and hyperadrenocorticism)
Older/younger (choose) animals physiologically have a higher blood pressure.
(Older)
Give an example of a dog breed with a physiologically higher blood pressure compared to other breeds.
(Sighthounds)
What is the drug class and action of amlodipine?
(Calcium channel blocker which relaxes vascular smooth muscle causing vasodilation and decreased systemic vascular resistance)
Amlodipine is the first line treatment for hypertension in dogs/cats (choose).
(Cats)
What is the drug class and action of benazepril/enalapril?
(ACE inhibitor, inhibits RAAS by blocking the action of ACE)
How do ACE inhibitors and angiotensin II receptor blockers decrease proteinuria?
(By causing dilation of the efferent arteriole of the glomerulus and reducing pressure within the glomerulus)
What can be a downside to the glomerular effects of ACE inhibitors and angiotensin II blockers?
(Azotemia d/t decreased GFR, should check patient for renal function prior to using these and recheck after 7-10 days)
If you overdose a patient with ACE inhibitors and angiotensin II blockers, what electrolyte abnormalities should you expect to see?
(Hyponatremia and hyperkalemia)
What is the drug class and action of telmisartan?
(Angiotensin II receptor blocker, inhibits RAAS by blocking action of angiotensin II)
What are the emergency drug options that should only be used with severe life-threatening hypertension?
(Direct arterial vasodilators such as hydralazine and sodium nitroprusside)
What type of drugs are typically used when pheochromocytomas are involved in hypertension cases?
(Alpha adrenergic antagonists such as phenoxybenzamine and prazosin)
What drug is typically used when hyperaldosteronism is involved in hypertension cases?
(Spironolactone → diuretic that acts as an aldosterone antagonist)
What signs should you warn an owner of when placing a patient on an antihypertensive drug to monitor for hypotension?
(Weakness or syncope, will find tachycardia on initial examine and hypotension with BP measurement)
What are the possible areas of target organ damage associated with hypertension?
(Eyes, kidneys, brain, and heart/vasculature)
