ANSWERS (LATEST)
Treatment of CHF - ANSWERS-Digoxin (increases cardiac
contractility), diuretics (increases NA and H2O excretion), ACEI
(decreases BP and BV), Vasodilators (decreases BP), dobutamine and
dopamine and PDE inhibitors (increase ventricular contractility)
Digoxin - ANSWERS-class: cardiac glycoside
increases myocardial contractile force and increases cardiac output
has a positive inotropic effect by inhibiting sodium potassium tump
(this increases Calcium into cell).
decreases HR
decreases AV nodal conduction
* USED FOR HF AND DYSRHYTHMIAS*
Digoxin toxicity - ANSWERS-warn patients about dig induced
dysrhythmias and instruct to take meds exactly as prescribed. toxicity
symptoms are altered hr or rhythm, visual or gi disturbances (nausea,
anorexia, vomitting, fatigue, blurred vision, yellow tinge to vision).
toxicity is made much worse by hypokalemia or anything that
decreases digoxin clearance.
Treatment: d/c digoxin, correct potassium, administer digibind
,Digoxin pharmacokinetics - ANSWERS-good PO absorption but
capsules are better than tablets. don't switch forms once prescribed.
dosage is based on lean body weight and is really excreted.
therapeutic levels are 0.5-0.8ng/ml.
half life is 1.5 days. 6 days required to reach plateau and 6 days to
eliminate.
Digoxin drug interactions - ANSWERS-Antacids: decease absorption
diuretics: cause hypokalemia and increase toxicity
quinidine: displaces dig from tissues and decreases excretion
amiodarone: increases concentration of dig
verapamil: increase plasma levels of dig
sympathomimetics: increases chance of arrthymias
How do ACEI work in CHF? - ANSWERS-inhibitor of ACE
decreases angiotensin II, decreases total peripheral resistance, and
decreases blood volume. decreased aldosterone decreases TPR and
BV.
Block the production of angiotensin II, decrease the release of
aldosterone, and suppress degradation of kinins. arteriolar dilation
improves blood flow in kidneys, venous dilation reduces venous
pressure, edema, preload, and suppression of aldosterone release
enhances excretion of sodium and water . contribute to cardiac
remodeling!!! prolong life. not in acute decompensated HF. excreted
by kidneys
, FIRST LINE TREATMENT IN CHF!!!!
ACEI side effects - ANSWERS-cough, increased potassium,
dizziness, angioedema, hypotension. can cause renal failure in
patients with bilateral renal artery stenosis. use with caution in
patients taking potassium supplements or k sparing diuretics,
neutropenia
DDI: diuretics can intensify hypotension, antihypertensive agents can
increase powered bp, risk of hyperkalemia with k sparing diuretics
and k supplements, NSaids and Lithium decrease effects of ACEI
BBW: can cause fetal injury in pregnancy.
Lisinopril - ANSWERS-ACE inhibitor that is given in active form
decreases TPR, Na and H2O load by inhibiting ACE.
block angiotensin II, decreases BO and salt and water retention.
longer 1/2 life. q day dosing. causes first dose syncope, dizziness, GI
SE
approved for MI, HTN, heart failure.
Angiotensin 2 receptor blockers - ANSWERS-approved for
hypertension, heart failure, diabetic nephropathhy, MI, prevention of
MI and stroke