Block 2-Reymann (CHF)

Question 1

Treatment of CHF

Answer 1

• Traditional meds:
• Digitalis
• Nitrates -^{<u><strong> Venous increased cap.</strong></u>}
• Diuretics - ^{<u><strong>REDUCED Preload</strong></u>}
• Hydralazine - ^{<u><strong>Dialate arterioles</strong></u>}
• In combo w/:
• ACE inhibitors - work BOTH arterioles & Veins dialation
• Beta blockers
• AT2 antagonists
• Spironolactone
• Net effect=Decreased ^{<u><strong>preload &amp; afterload </strong></u>}w/INCREASED contractility & reduction of remodeling of vent muscle

Question 2

Cardiac Glycosides (Digoxin & Digitoxin)

Answer 2

• Digoxin = 1/2 life ^{<strong>40 hours</strong>} w/Renal excretion
• Digitoxin = 1/2 life of^{<strong> 5-7 DAYS</strong>} w/hepatic excretion
• Both show slow compliance
• In emergency situation of arrythmias ^{<u><strong>(FAST sat.)</strong></u>} use loading dose of IV bolus
• Always check plasma **LVLs Digoxin after 1 week **
• Take days for pt to go back to normal lvls
• Increase contractility (+ ionotropic) due to increased Ca+2 following inhibition of Na/K ATPase pump
• Decrease in Sinus rate (- chronotropic) in CHFpts - ^{<strong>FAST & WEAK PULSE</strong>}
• Decrease in AV nodal conduction (- dromotropic)-^{<strong>QT shortened & ST DEPRESSED</strong>}
• INCREASE in automaticity & excitability in atria

Question 3

Cardiac Glycosides (Digoxin & Digitoxin) Uses

Answer 3

• Increased contractility w/decrease in HR:
• Increased CO
• Improved perfusion & O2 of periphery
• Improved diuresis & mobilization ^{<u><strong>(resorption)</strong></u>} of edema
• Reduced sympathetic tone & vasocontriction
• Reduction of peripheral resistance ^{<strong>(afterload)</strong>} due to reduction in preload=^{<strong>LESS diastolic load</strong>}
• Less of myocardial overdistention
• Balance of myocardial O2 consumption due to improved effciency
• Improvement of exercise intolerance ^{<strong>BUT NO SIGNIF DECREASE IN MORTALITY</strong>}
• CHF pts improved supravent tachy

Question 4

Cardiac Glycosides (Digoxin & Digitoxin)

Answer 4

• PK:
• Monitor plasma lvls during application of any other drugs
• 100% increase in plasma lvls seen w/CCB
• PD:
• Diuretics^{<strong> (K+ wasting & K+ sparring)</strong>}, ACE inhibitors
• SA/AV conduction ^{<u><strong>(B-blockers &amp; CCB)</strong></u>}
• Increased automaticity through Beta-2 agonists ^{<strong>(Allobut_asthma)</strong>}
• SE:
• Arrhythmia-
• Tachy premature vent contractions & vent fibrillation ^{<strong>(LOW CA+2)</strong>}
• Brady paroxysmal & nonparox atrial tachy, AV-block ^{<u><strong>(SUDDEN ONSET)-</strong></u>}HIGH CA+2
• GI-disturbance=Anorexia, Diarrhea
• CNS- Delerium & Halos

Question 5

Cardiac Glycosides (Digoxin & Digitoxin) Toxicity

Answer 5

• Hypokalemia = Tachy
• Hyperkalemia = Brady (Supressed auto) Treat w/temp pacemaker
• Drug accumulation/Overdose due to ^{<u><strong>LONG 1/2 LIFE</strong></u>}
• Hypomag or Hypercal-Dieuretics
• Hyperthyreosis ^{<u><strong>(HYPERTHYROIDISM)</strong></u>}
• Abnormal renal fnx
• Resp disease
• Acid/Base imbalances^{<u><strong>(Hypo &amp; Hyperkalemia)</strong></u>}
• Treatment of Toxicity:
• Adjust electrolyte
• Vent tachy _^{<strong>(lidocaine, magnesium HELP </strong>}_adjust K+ to normal)
• SEVERE intoxication = Hyperkalemia
• Treat w/digitalis Ab ^{<u><strong>(DIGIBIND/DIGOXINE)</strong></u>}

Question 6

Digoxin Indications

Answer 6

• Indications:
• CHF- NYHA 3 (reduced physical capacity w/SLIGHT activity) or NYHA 4 (Symptomatic @ rest)
• Antiarrythemic therapy of atrial flutter or atrial fibrillation
• NON-indications(do NOT Use):
• Cardiac-glycosides are INEFFECTIVE in myocarditis ^{<u><strong>(heart muscle inflammation) </strong></u>}OR cor-pulm ^{<u><strong>(right side failure)</strong></u>}
• Uncontrolled Hypertension
• Treating Bradyarrthy
• Non-responders or intolerance

Question 7

Inhibitors of angiotensin (ACE)

Answer 7

• ACE: Captopril, enalapril, lisinopril - Used for Hypertension & CHF
• PK:
• Oral 1/2 life 2hrs & renal elimination
• Max daily does no more than 150mg
• PD:
• Ang 2-Antagonism- Decreased-
• Vasoconstriction
• NE release
• Aldosterone release
• Bradykinin related-Vasodialtion-
• No reflex tachy
• no change in CO
• NO water-Na+ retention
• Slight reduction of SNS tone

Question 8

Inhibitors of angiotensin (ACE) SE

Answer 8

• Captopril
• Se:
• Hypotension
• Dry cough w/bronchospasm
• Skin rashes & edema
• Low neutrophil & WBC count
• Hyperkalemia
• Protenuria
• CI:
• Renal artery stenosis will lead to_^{<strong> RENAL FAILURE</strong>}_
• Recurrent angioedema (asthma/COPD)
• Pregers
• Toxicity:
• Symptoms hypotension w/o marked reflex tachy

Question 9

Captopril Interactions

Answer 9

• NSAID-reduce anti-hypertensive response by interaction w/bradkinin
• K+sparring diuretics = Hyperkalemia
• K+wasting diuretics = MORE wasting
• Hypersensitivity rxns to other drugs can be aggravated
• Increased lvls of digoxin or lithium

Question 10

ACE inhibitor Enalapril

Answer 10

• Intrahepatic conversion
• PK: oral
• max dosage of 40mg
• IV use for emergency hypertension
• PD & SE compared to captopril:
• MORE potent ^{<u><strong>(slower onset/longer duration of action)</strong></u>}
• Contrain no SULFA groups ^{<u><strong>(NO taste perversion)</strong></u>}
• Hepatic elimination = Fosinopril & Moexipril
• Use:
• Hypertension
• CHF-prevention or delay
• Decrease incidence of sudden death & MI
• Progressive renal disease (diabetics)

Question 11

Losartan AT-1 blocker

Answer 11

• Non-peptide Angiotensin 2 receptor antagonist/blocker
• PK:
• Oral & 1/2 life of 2hrs
• hepatic elimination
• PD: like ACE-inhibitors
• UNLIKE ACE: NO effect on degradation of bradykinin
• SE: LIke ACE-inhib
• UNLIKE-NO bradykinin related cough or edema
• CI:
• Renal artery stenosis
• Pregers

Question 12

Beta-Blockers

Answer 12

• Use in CHF:
• Low dosage & go slow increase dosage every 2 weeks
• Assesment before every INCREASE dose ^{<u><strong>(NYHA 3 &amp; NYHA 4)</strong></u>}
• Late onset of therapeutic effect onset 3 months & FULL effect almost 1 year
• Give in combo w/Diuretics, ACE inhib, Digitalis & keep CONSTANT
• SE:
• sedation or hypostension (^{<u><strong>reduce diuretics or ACE-inhibitors)</strong></u>}
• Edema_^{<strong> (Increase diuretic)</strong>}_
• Bradycardia/AV block ^{<u><strong>(Reduce digitalis)</strong></u>}

Question 13

Ionotropic drugs used in Acute Cardiac failure

Answer 13

• _Dopamine: IV _
• Low-act on dopamine receptors (Kidney)
• Intermid-Act on Beta-1 receptors
• High-Act on alpha1 receptors
• Dobutamine: IV acts on alpha 1, beta 1 & 2 receptors
• Increases CO w/little effect on CO
• Amrinone & Milirinone (Viagra)
• Increase Myocardial cAMP by inhibition of PDE 3 ^{<u><strong>(PHOSPHODIESTERASE)</strong></u>}
• Increase sensitivity of contractile system to Ca+2
• Induce arterial & venous dialation