Kaplan Flashcards
What does the relatively high resting potential of the slow response fiber indicate?
They can fire AP by themselves
What ions are responsible for the AP of slow response fiber?
Slow Ca current and then delayed K current
How are Na/Ca/K channels and pacemaker current in slow response fiber affected with beta 1 receptor? what about M2?
Gs open Na/Ca channel and close K channel for AP/steepen pacemaker current/Gi does the opposite—>flatten the pacemaker current
What is the m and h gate of Na channel?
M is the activation gate
H is the inactivation gate—>responsible for refractory period
What do class Ia/b/c Na channel blockers block?
Ia—>block activated form of Na channel (both m and h gate are opened)
Ib—>block inactivated form (m open, h closes)—>prevent the channel from going back to be activated and firing
Ic—>block resting
Which class of Na channel is used for arrhythmic post MI?
Class Ib
Na is reabsorbed the most in what part of the nephron? and what follows it?
Proximal tubule/bicarb, Cl and water
What is the permeability of thin descending limb?
Water reabsorption w/o solutes reabsoption
Diuretics causes ___ and ___?
Hypokalemia and alkalosis
Osmotic diuretics work on what part of the nephron and mainly which part?
the entire tubule/mainly on proximal tubule
Carbonic anhydrase inhibitor increase ___ and ___ con. inside of the lumen?
Na and HCO3-
What symptoms carbonic anhydrase inhibitor treat regarding acute mountain sickness?
- Respiratory alkalosis caused by hyperventilation
2. Edema caused by increase hydrostatic pressure from hypoxic vasoconstriction
How does renal stone happens with carbonic anhydrase?
Increase urine pH
Loop diuretics causes hypo___?
hypo every single ions!
For treating HTN, loop diuretics vaso___ by increasing ___? what drug can cancel this effect?
vasodilate/increasing prostaglandin/NSAIDs
Why is sulfonamide common in drugs and what drugs have sulfur in them? (watch for allergic reactions)
Sulfur containing drugs are lipid soluble and binds to protein/all the sulf- and thio- drugs have sulfur in them—>as well as carbonic anhydrase inhibitor, loop diuretics except for ethacrynic acid
Weak acid diuretic drugs (thiazide) that is secreted in the proximal tubule competes with ___? which causes ___?
Urinate/hyperuricemia (contraindicates in pt with gout)
Thiazide causes hypo/hypercalcemia? that as a result treats ___?
Hypercalcemia/nephrolithiasis (Ca stone)
Thiazide causes ___ release and should be avoided with ___ pts?
Insulin resistance—>hyperglycemia/hyperlipidemia/diabetes mellitus pts
Turn borderline diabetics into full blown diabetics
Diuretics causes drop of __ and __? but eventually ___ returns to normal?
BP and CO/CO
Which is more potent, ACEI or ARB?
ACEI (due to inhibition of the breakdown of bradykinin)
Why do use ACEI for chronic kidney disease?
e.g. HTN causes kidney failure—>kill a lot of glomeruli—>the remaining glomeruli compensate and over work—>RAS is activated—>further kidney damage and more glomeruli die—>if block RAS with ACEI—>kidney function decrease but eventually plateau (prevent burnout)
With a drug that decrease symp tone to decrease BP, you would expect to see?
No reflex tachy/orthostatic HoTN/increase parasymp
Alpha 2 receptor is G_ coupled?
Gi
Alpha 2 agonist drugs for HTN would interact with what other drugs?
TCA
Reserpine causes severe?
Depression
Beta blocker would decrease ___ so it is contraindicated in pt with high ___?
Lipolysis—>increase lipid in blood/lipid
What are the 2 groups of HTN drugs that do not have reflex tachycardia?
Alpha 2 agonist/beta blockers
What are the 2 drugs for HTN in during pregnancy?
Methyldopa/hydralazine
Long term use of minoxidil induces?
Diabetes
Which one has stronger vasodilating effect, dihydropridine or non-dihydropyridine?
Dihydropyridine
What drugs causes gingival hyperplasia?
Dihydropyridine
ACEI/ARB causes hyper or hypokalemia?
Hyperkalemia (lack of aldosterone)
Use ACEI/ARB for pt with renal stenosis will induce?
Acute renal failure
What would class Ia anti arrhythmic drugs do to phase 0 and the AP?
Decrease the slope of phase 0/prolonged AP
What is causing Quinidine’s pro arrhythmia effect?
M and Alpha blockade—->tachycardia
Hyper or hypokalemia would worsen LQT?
Hyperkalemia
What are the 4 drugs that cause SLE like syndrome?
Hydrazine/procainamide/isoniazid/methydopa
How does thiazide treat nephrogenic diabetes insipidus?
Increase aldosterone release in distal tubule and increase water reabsorption
What does class Ib drug do to the AP?
decreases the duration of AP
Beta blocker for anti arrhythmia work on ___ and ___ node and promote ___?
SA and AV node/parasymp
What does beta blocker do to the pacemaker AP?
Decrease the slope of phase 4—>takes longer for it to achieve another AP
What drugs causes pul fibrosis?
Amiodarone/bleomycin
Class IV anti arrhythmic drugs work on ___ and ___ in the heart? and what does do to the pacemaker AP?
SA and AV node/decrease phase 0
You need to give ___ before you give quinidine?
Digoxin
What is the mechanism of adenosine?
Gi coupled—>decrease cAMP—>decrease AV and SA node activity
Carvedilo/labetolol/ACEI/ARB/spironolactone are used for?
Interfere with negative cardiac remodeling—>increase survival of CHF
Digoxin is used for? and how does it work?
Increase contractility—>increase CO in CHF pts and also for SVT/inhibit Na/K pump—>increase intracellular Na and Ca leve
What does milrinone do?
Increase contractility for heart failure pts
What is the side effect of Digoxin?
Cardiac arrhythmia
Digoxin interact with ___ to increase toxicity?
Diuretics (hypokalemia)
What anti arrhythmic drugs treat SVT?
Class II and IV/adenosine/Digoxin
What to give for WPW pts?
Class Ia and III
How does nitrite work?
Venodilate at smooth muscle cell of the large veins—>decrease preload—>decrease cardiac work and O2 demand
Difference in mechanism of dihydropyridine and non dihydropyridine?
Non di—->work on heart—>decrease contractility
di—>coronary vasodilator
Don’t use beta blocker for ___ angina?
Vasospastic (printzmetal)
How does cAMP cause smooth muscle relaxation?
cAMP phosphorylates (inactivate) myosin light chain kinase
High cholesterol causes low ___ receptor on hepatocyte? which results in?
LDL (liver don’t need more fat anymore)/the formation of plaque
What is the mechanism of statin?
Inhibit HMG-CoA—>decrease liver cholesterol—>increase LDL receptor—>decrease plasma LDL
Also decrease TG
Statin should not be used with gemfibrozil because?
Increased risk for rhadomyolysis
Bile aid sequestrants are contraindicated in hyperTG pts because?
It forces liver to take up LDL and then produces more VLDL—>causes hyperTG
What can you give to counter the side effect of niacin?
Aspirin
Asthma is under the category of ___? and it is characteristics of ?
COPD/bronchospasm
What to give for acute and chronic asthmatic response?
Acute—>bronchodilator
Chronic—>anti-inflammatory
What are the 3 factors that causes bronchoconstriction?
ACh/Adenosine/leukotriene
What mediates bronchodilation? what kind of drugs can achieve these?
Increase cAMP and cGMP/Beta 2 agonist and phosphodiesterase inhibitor
What is the side effect for beta 2 agonist for asthma?
Epi like effect—>fight or flight (anxiety and what not)/eventually go away
What is the drug of choice for pt on beta blocker that experience bronchospasm?
Ipratropium
What is status asthmaticus?
Acute asthma over 60 mins
What else is cromoglycate and nedocromil used for?
Seasonal allergy
Should we treat HTN in women more conservatively or aggressively?
Aggressively
How does ACEI prevent kidney failure and diabetic nephropathy? and what do you expect to see at the beginning of the treatment?
ACEI decrease GFR purposely to reduce hyperfiltration–>eventually level off/increase in creatine due to decrease in GFR
What is the first line treatment for HTN in general?
ACEI/diuretics
Why thiazide is use the most for diuretics for HTN?
Long acting
When do you use loop instead of thiazide for HTN?
When GFR is
What should you consider when giving diuretics to athletes?
It dehydrate ppl, lowers CO and make people feel fatigue
Thiazide might push people on the edge of being ___ to be ___?
Diabetics
Beta blockers causes ___ unawareness
Hypoglycemic (caution to use with diabetics)
Beta blockers raise serum glucose
HTN pt with CAD, give?
CCB
Di or non-di are good for chronic kidney disease?
Non-di
Beta blocker can worsen?
Asthma
Does beta block increase or decrease serum lipid?
Increase
What are beta blockers with sympathomimetic activity?
Partial agonist of beta receptors (less effective)
EAD is worsen by high or low HR/long or short QT interval?
Low HR and long QT interval
Mobitz type I AV block response to?
Anti parasymp (atropine)
What to give pt with diastolic CHF?
Nitrite/diuretics
What are the 3 beta blockers that decrease morbidity in HF?
Carvediolol/metoprolol/bisoprolol
What is the side effect of nitrite besides HoTN?
Headache
If a HF pt cant get ACEI or ARB, give what?
Hydralazine or nitrite