Heart Failure Flashcards
Drugs that improve contractility (positive inotropes)
Epi, NorEpi, isoproterenol, dopamine, dobutamine, digitalis-like drugs, calcium, milrinone
Drugs that decrease contractility (negative inotropes)
CCBs, B-blockers
Acidosis acts like a negative inotrope
Preload
Amount of stretch @ the end of diastole
Afterload
The amount of resistance the heart must overcome to open the aortic valve & push the blood volume out into systemic circulation
Ejection fraction
The amount of blood pumped by the L ventricle w/each heart beat
How is EF calculated?
Subtracting the amount of blood present in L ventricle @ the end of systole from the amount present @ the end of diastole & calculating % of blood that is ejected
Difference b/t systolic and diastolic dysfunction
- Systolic dysfunction = L ventricle becomes weak/flabby, not able to contract forcefully/loses ability to eject blood; HF w/reduced EF
- Diastolic dysfunction = L ventricle stiffens/bulks up, can contract, but no relax afterwards —> decreased filling; HF w/preserved EF
L-sided HF S/S
- Pulmonary congestion, crackles
- S3 (“ventricular gallop”)
- Dyspnea on exertion
- Low O2 sat
- Dry, nonproductive cough initially
- Oliguria
R-sided HF S/S
- Viscera & peripheral congestion
- JVD
- Dependent edema
- Hepatomegaly
- Ascites
- Weight gain
S/S of pulmonary edema
Restlessness, anxiety, dyspnea, cool/clammy skin, cyanosis, weak/rapid pulse, cough, lung congestion (moist, noisy respirations), increased sputum (frothy, blood tinged), decreased LOC
What can manifest as pulmonary edema?
Acute decompensated HF (ADHF)
Pulmonary edema
Management
- Early recognition: monitor lung sounds & for S/S of decreased activity tolerance, increased fluid retention
- Minimize exertion
- Oxygen via nonrebreather
- Meds: furosemide, nitroglycerin
Pulmonary edema
Nursing interventions
- Position pt upright w/legs dangling (best position for circulation)
- Monitor response to RX and I&O
What is the hallmark sign of systolic failure?
Decreased EF
How is diastolic dysfunction confirmed?
Echocardiogram, cardiac cath
Causes of R-sided HF
- Primary = L sided HF
- R ventricular infarction
- PE
- Cor pulmonale (RV dilation & hypertrophy S/T pulmonary disease)
What kind of dysrhythmias are HF patients @ risk for?
Ventricular dysrhythmias, atrial fib
What are the main compensatory mechanisms to maintain adequate CO?
- Neurohormonal: RAAS & SNS
- Ventricular dilation
- Ventricular hypertrophy
What affect to catecholamines have on cardiac fxn?
- Increased HR
- Increased myocardial contractility
- Enhanced peripheral vasoconstriction
What does ventricular remodeling occur in response to?
Continuous activation of neuro-hormonal responses (RAAS, SNS)
What happens in ventricular remodeling?
Ventricles get large, but less effective in pumping
Consequences of ventricular remodeling
Life-threatening dysrhythmias, sudden cardiac death
Drugs to prevent/reverse remodeling
ACEs, b-blockers, aldosterone antagonists
When are ANP and BNP released?
Released from overdistended cardiac chambers in response to increased blood vol in heart
What are the effects of ANP and BNP?
- Causes diuresis, vasodilation, and lowered BP
- Counteracts effects of SNS and RAAS in pts w/HF
Diagnostic tests for HF
Echocardiogram, ECG, CXR, 6-min walk test, cardiopulmonary exercise stress test, heart cath, endomyocardial biopsy
Labs for HF in initial assessment
Lytes, BUN, creatinine, LFTs, TSH, CBC, BNP, routine UA
Which lab study is used to determine degree of HF?
BNP
Other causes of increased BNP
PE, renal failure, ACS
HF medications
ACEs
Vasodilation, diuresis, decreased afterload
Monitor for hypotension, hyperkalemia, altered renal function, cough
HF medications
ARBs
Alternative to ACE’s (if pt unable to tolerate)
HF medications
Hydralazine and isosorbide
Alternatives to ACEs
HF medications
B-blockers
RX’d in addition to ACEs
May take several weeks for effects to be seen; use w/caution in pts w/asthma
HF meds
Diuretics
Decrease fluid vol
Monitor lytes
HF medications
Digitalis
Improves contractility
Monitor for toxicity
HF medications
ADHF - IV meds
Milrinone (decreases preload & afterload —> hypotension, increased risk of dysrhythmias)
Dobutamine (L ventricular dysfunction, increases contractility & renal perfusion)
Gerontological considerations
- May present w/atypical S/S - fatigue, weakness, somnolence
- Admin of diuretics to older men —> bladder distention S/T urethral obstruction from enlarged prostate (close monitoring)
What are possible complications of HF?
Hypotension, poor perfusion, cardiogenic shock
Dysrhythmias
Thromboembolism
Pericardial effusion and cardiac tamponade
Cardinal signs of cardiac tamponade
Falling systolic BP, narrowing pulse pressure, rising venous pressure, distant heart sounds
Pericardiotomy
Under general anesthesia, a portion of the pericardium is excised to permit the exudative pericardial fluid to drain into the lymphatic system
