treatment of heart failure Flashcards
what is symptomatic tx of heart failure
- improve systolic and diastilic heart function
- eliminate aggravating conditions (arrhythmias, infection, hypertension, electrolyte abnormalities)
- control signs of congestion
- avoid drug adverse effects
how to manage systolic and diastolic function of myocardium
- increase contractility
- improve relaxation
- minimize hypertrophy, fibrosis, remodeling
how to reduce cardiac work
- reduce afterload
- reduce tachycardia
- control obesity
how to control congestion
- reduce preload
- manually drain pleural and abdominal effusion
- reduce sodium intake
what is diastolic heart failure
- feline hypertrophic cardiomyopathy (HCM)
- excessive concentric hypertrophy
- impaired diastolic relaxation
- increased myocardial stiffness (decreased compliance)
- normal systolic function
what is the consequense of increased myocardial stiffness
- increased stiffness/decreased compliance
- increases in volume (preload) cause increased diastolic pressure
- increased venous pressure causes congestion
how do you reduce preload by relieving congestion
diastolic pressure in ventricle/atrium/veins
increase fluid excretion
- loop diuretics: furosemide
increase venous capacitance
- venous vasodilators: nitrates
what do you use to reduce preload and afterload
ACE inhibitors (in conjunction with furosemide)
what are the effects of ACEI
- reduces afterload
- makes it easier for heart to eject blood forward (better cardiac output)
- reduces preload
what is myocardial oxygen demand (MVO2)
- proportional too wall stress x HR
- wall stress is proportional to systolic blood pressure
how do you reduce myocardial work
- lengthen diastolic filling time
- reduce obstructions to flow (decrease HR, contractility)
what drugs do you use to slow HR and increase diastolic filling time
- beta-adrenergic receptor blockers - decrease sympathetic tone - sinus node
- Ca2+ channel blockers - decreases Ca2+ dependent depolarization - sinus node
what are the side effects of diuretics
- hypovolemia
- electrolyte abnormalities
- pre-renal azotemia
- acute kidney injury
what are the side effects of ACEI
- kidney injury
- hypotension
what are the side effects of beta-blockers and Ca-blockers
bradycardia
what is the FOND protocol
- Furosemide
- Oxygen
- Nitroprusside or nitroglycerine
- Dobutamine, dopamine, digoxin
FOND
what is furosemide
- Lasix
- potent, rapid acting, IV/IM/SQ
- short half life
- monitoor urine production
- monitor hydration status
- monitor renal function
- consider constant rate infusion
FOND
what is oxygen
- if SaO2 <90%
- oxygen cage: FiO2 = 40-60%
- intranasal O2: 100% O2
- positive pressure ventilation
FOND
what is nitroprusside
- produces nitric oxide (NO)
- potent mixed vasodilator
- venouos vasodilator: reduce preload
- arterial vasodilator: reduce afterload
- very short half life
- CRI: 2-15 ug/kg/min
- dilute in 5% dectrose, protect from light
- monitor blood pressure to avoid hypotension
FOND
what is dobutamine infusion
- sympathomimetic (synthetic B1-agonist, increases contractility)
- very short half life (CRI: 2.5 to 20 ug/kg/min)
- dilute in 5% dextrose
- side effect: tachycardia (monitor HR and rhythm)
- relatively expensive compared to dopamine
FOND
what is dopamine infusion
- endogenous B-agonist
- also binds dopamine and a-receptors
- very short half life (CRI 2-8 ug/kg/min, dilute in 5% dextrose)
- side effects: vasocontriction at high doses, tachycardia
- monitor HR & rhythm
what is an alternative to FOND
- Furosemide
- Oxygen
- ACEI
- Pimobendan
FOAP
what is pimobendan
- calcium sensitizer (increased contractility - positive inootrope)
- phosphodiesterase inhibitor (atrial vasodilator)
- “inodilator”
what are the adverse effects of ACEI
- renal dysfunciton
- hypotension
- hyperkalemia
what is the limitation of ACEI therapy
- incomplete suppression of RAAS
- “adosterone breakthrough (ABT)”
