Acute HF Flashcards
What is the pathophysiology of acute HF?
Cardiogenic shock: hypotension (SBP <90 or MAP <70) w low CO
What are the diagnostic tools?
Non invasive testing:
- Detailed physical examination
- Laboratory assessment (Cr, K, Na, BNP, NTproNBP)
Invasive hemodynamic monitoring:
- Flow directed PA cath (Swan-Ganz cath)
What BNP level is closely associated w acute HF?
BNP >400
What sx is associated w warm and dry?
Normal
What sx is associated w warm and wet?
Pulmonary congestion
What sx is cool and dry?
Hypoperfusion
What sxs are associated w cool and wet?
Hypoperfusion and pulmonary congestion
What does warm or cold describe?
Cardiac function or ability to perfuse tissues
What does wet or dry describe?
Describes volume status
How to maintain chronic diuresis and RAAsi/SGLT2i?
- Caution w increases and up-titration
- Increases in SCr (about 20%) do not worsen outcomes
- Significant worsening may warrant reduction or temporary d/c
How to maintain chronic BBs?
- Do not stop unless recent initiation or up-titration resulted in current decompensation
- Consider holding if dobutamine needed or hemodynamically unstable
- Do not add or up titrate until optimization of volume status and successful d/c of IV diuretics, VDs, inotropes
- Start at low doses and use special caution if inotropes used in hospital
How to maintain chronic digoxin?
- Continue at dose to achieve SDC 0.5-0.9 ng/ml
- Avoid d/c unless compelling reason
- Caution w regard to renal function
What do diuretics, inotropes, vasodilators, vasopressors do?
- None of these therapies shown conclusively to reduce mortality
- Tx reduce sxs, restores perfusion, and minimizes cardiac damage and AEs
What tx is used for subset 1 warm and dry?
Optimizes chronic therapy
What tx is used for subset 2 warm and wet?
IV diuretics +/- IV venous vasodilator
What tx is used for subset 3 cold and dry?
- If PCWP <15: IV fluids until PCWP 15-18
- If PCWP >= 15 and SBP <90: IV inotrope
- If PCWP >= 15 and SBP >= 90: IV inotrope or arterial vasodilator
What tx is used for subset 4 cold and wet?
IV diuretics +
- If SBP <90: IV inotrope
- If SBP >= 90: IV arterial vasodilator
When are diuretics mainly used?
To tx systemic/pulmonary congestion in subset 2 or 4, first line agents w fluid overload in hospitalized pts
Is there a difference between intermittent dosing and continuous infusion?
No
What dose of diuretics is administered?
Initial IV dose should equal or exceed the chronic daily dose and given as intermittent bolus
Which diuretic is mainly used?
Loops are most widely used, THZ used as add on if refractory
What should be done if there is diuretic resistance?
- Sodium and water restriction
- Increase dose, rather than frequency, to ceiling
- Combo therapy (THZ + loops): PO MTZ 2.5-5 mg/day, HCTZ 12.25-25 mg/day; IV CTZ 250-500 mg/day
- Ultrafiltration
How to dose diuretics in hospitalized pts?
- Increase dose pt was receiving at home
- If ceiling effect: 160-200 mg IV furosemide (depends on renal fx)
- If continuous infusion: F 0.1 mg/kg/hr doubled q2-4h; max 0.4 mg
What are monitoring parameters of diuretics in hospitalized pts?
- Urine output and s/sxs of congestion, should be serially assessed
- Ins/outs, body weight, vital signs, s/sxs of perfusion and congestion
- Serum electrolytes, BUN, creatinine daily
- Desire 1-2 L/day above input early
What is the use of loops in ADHF?
Fluid overload (wet)
What drug can be used if pt cannot take loops for ADHF?
Ethacrynic acid
What is the approximate PO/IV equivalent dose of furosemide?
80/40 mg
What is the approximate PO/IV equivalent dose of bumetanide?
1/1 mg
What is the approximate PO/IV equivalent dose of torsemide?
20/20 mg
What is the initial IV bolus dose of furosemide?
40-120 mg
What is the initial IV bolus dose of bumetanide?
1-4 mg
What is the initial IV bolus dose of torsemide?
10-40 mg
What is the initial IV bolus dose of ethacrynic acid?
0.5-1 mg/kg
What is the max bolus dose of furosemide?
160-200 mg
What is the max bolus dose of bumetanide?
10 mg
What is the max bolus dose of torsemide?
100 mg
What is the infusion rate of furosemide?
10 mg/hr
What is the infusion rate of bumetanide?
0.5 mg/hr
What is the infusion rate of torsemide?
0.5 mg/hr
What is the purpose of vasodilator therapy in ADHF?
Use in combo w diuretics to reduce pulmonary congestion in wet, stage 2 and 4, HF
Why do vasodilators work?
Venodilators increase venous capacitance and reduce preload and reduce myocardial stress:
- Rapid sx relief
Which vasodilator is the most preferred drug of choice?
NTG
When are arterial vasodilators particularly useful?
In pts w elevated SVR
When should a pt not receive vasodilators?
Symptomatic hypotension
Vasodilators are considered over:
Inotropes
What is a required monitoring parameter w the use of vasodilators?
Frequent BP
What are the clinical effects of nitroprusside (Nitropress)?
- Balanced vasodilator
- Decreases SVR
What is the use of nitroprusside in ADHF?
- Warm and wet
- Cold and wet (alt to inotropes)
- HTN crisis
What are the AEs of nitroprusside?
- Cyanide and thiocyanate toxicity (usually w >3 days use)
- Hypotension
What are the clinical effects of NTG?
- Venous > arterial VD
- Decreased PCWP
What is use of NTG in ADHF?
- Warm and wet
- ACS, HTN crisis
What are the AEs of NTG?
Hypotension, HA, reflex tachycardia, and nitrate tolerance
What are the clinical effects of nesiritide (natrecor)?
- Balanced vasodilation
- Increased urine output and Na excretion
What is the use of nesiritide in ADHF?
- Warm and wet
- Cold and wet (alt to inotropes)
What are the AEs of nesiritide?
Hypotension, tachycardia, renal dysfunction
What drugs are positive inotropes?
Dobutamine (Dobutrex), Milrinone (Primacor), Dopamine
What is the MOA of dobutamine (Dubotrex)?
- B1 and B2 receptor agonist and weak A1 receptor agonist
- Simulates AC to increase cAMP
What are the clinical effects of dobutamine?
Positive inotrope, chronotrope, lusitrope
What is the use dobutamine in ADHF?
- Cold and wet
- Cold and dry (if PCWP >15)
When is dobutamine considered?
Consider if low BP
What are the AEs of dobutamine?
Arrhthmogenic, tachycardia, ischemia, reduced K, tolerance after 48-72hr
What is the MOA of milrinone?
- PDE inhib, inc cAMP in myocardium (increased CO), and vasculature (decreased SVR)
- “Inodilator”
What are the clinical effects of milrinone?
Positive inotrope, venous > arterial VD
What is the use of milrinone in ADHF?
- Cold and wet
- Cold and dry (if PCWP >15)
What is the half life of milrinone?
1 hr in healthy, 2-3 hr in HF and CrCl <50
When is milrinone considered?
Consider if on BB
What are the AEs of milrinone?
Arrhythmogenic, tachycardia, ischemia, hypotension, thrombocytopenia (<0.5%)
What is the MOA of dopamine?
- Dose dependent agonist on dopamine, B1, B2, and A1 receptors
- Causes release of NE from adrenergic nerve terminals
What are the clinical effects of dopamine?
Positive inotrope, chronotrope, lusitrope
What is the use of dopamine in ADHF?
- Typically plays secondary role to dobutamine/milrinone
- Sometimes referred to as a vasopressor
What are the AEs of dopamine?
Arrhythmogenic, tachycardia, ischemia, decreased K, tolerance after 48-72h, skin necrosis upon infiltration
What is the use of positive inotrope therapy?
- Primarily to manage hypoperfusion or cold HF pts
- Reasonable to consider vasodilators before inotropes when adequate BP
- Useful for sx relief in hypotension (SBP <90)
- Useful in pts w end organ dysfunction
- Useful when disease is refractory to other HF therapies
What sxs would cool and dry (subset 3) pts have?
- Sxs of low output (cool) but not congestion (dry)
- i.e. inadequate perfusion w no congestion
What is the primary goal of therapy in subset 3 pts?
Increase output and perfusion w positive inotropes +/- IV fluids
What is the therapy for subset 3 pts?
- Initial therapy: fluids until BP maximized
- Therapy following fluids: if pts still remains “cool,” inotropic or arterial vasodilator therapy maybe required
