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172 Cards in this Set
- Front
- Back
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This is the inability of the heart to fill or eject blood at a rate adequate to meet tissue requirements.
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heart failure
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____ is the most common medicare discharge diagnosis.
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heart failure
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Symptoms of heart failure
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SOB, swelling BLE, chronic lack of energy, difficulty sleeping due to breathing problems, swollen/tender abdomen, loss of appetite, cough w frothy sputum, inc nocturnal urination, confusion/memory impairment
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What are the etiologic causes of HF?
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impaired myocardial contractility
valve abnormalities systemic HTN pericardial disease pulm HTN (cor pulmonale) |
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What is the most common cause of RV failure?
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LV failure
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Pts w systolic heart failure exhibit _____ Disease, dilated ______, and ____ and ____ chronic overload.
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CAD, dilated cardiomyopathy, chronic pressure and volume overload
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What cause chronic pressure overload in systolic heart failure?
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aortic stenosis, HTN
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What causes chronic volume overload in systolic heart failure?
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aortic and mitral insufficiency (leaking/regurg), high output failure
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Patients w diastolic HF may have normal _____ function.
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systolic
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What are the causes of diastolic heart failure?
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ischemia, aortic stenosis, HTN, anything that makes heart muscle hypertrophy
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Describe stage 1 of diastolic HF.
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abnormal relaxation (LVEDP incr) with normal left atrial pressure
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Describe stages 2-4 of diastolic heart failure.
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abnormal relaxation with high left atrial pressure and LVEDP
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Diastolic heart failure is more common in
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women
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Chronic heart failure is seen in pts with _______ cardiac disease. They exhibit ____ congestion, _____ BP, and the process is well tolerated because ______.
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long-standing,
venous congestion, well-maintained BP, bc it occurs gradually |
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Acute heart failure is seen in pts with the following conditions:
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MI, valve rupture, HTN crisis
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Pts w acute heart failure have _____ edema, ____ BP, and a more ______ presentation.
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no edema, hypotension, catastrophic presentation
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CAD, cardiomyopathy, HTN, valvular disease, and pericardial disease are all causes of _______ output heart failure.
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low output
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Anemia, pregnancy, AV fistula, hyperthyroidism, Beri Beri, and Paget's disease are all causes of _____ output heart failure.
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high output
av fistula- some blood that normally goes through lungs will take shortcut through fistula and too much may take shortcut |
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Starlings Law of the heart describes the relationship between ____ and _____.
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EDV and cardiac output
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In a normal person, the relationship between LVED volume and stroke volume is very _____.
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linear
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In a normal heart, increased preload leads to ____ CO.
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increased
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In pts w heart failure, the starling curve has a more _____ pattern. Increased preload does not improve ______. In fact, it may make things worse and decrease CO.
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flat curve, stroke volume
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Will pts in cardiogenic shock or severe heart failure respond to volume challenge?
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NOPE
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According to the NYHA, there are 4 classes of heart failure...
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1. no symptoms w ordinary activity
2. symptoms w ordinary exertion 3. symptoms w less than ordinary exertion 4. symptoms at rest |
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Describe the cocktail of drugs available for medical mgmt of heart failure.
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ace inhibitors, ARBs, aldosterone antagonists, B blockers, diuretics, digitalis (positive inotrope), vasodilators (Decr afterload), statins
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When medical management of heart failure is unsuccessful, the next step is...
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surgery
OHTX (orthotopic heart transplant) Ventricular assist device Cardiac resynchronization (to improve electrical conduction) ICD (implanted cardiac defibrillator) |
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When an LVAD is functioning normaly, the aortic valve does not need to ______.
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close
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How is acute heart failure managed?
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- diuretics and vasodilators
- inotropic support - Ca sensitizers (levosemindan) - B-type natriuretic peptide (Natrecor) - Nitric oxide synthase inhibitors - intra-aortic balloon pump |
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Milrinone works by preventing the breakdown of ___.
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cAMP
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When chronically giving pts meds to improve contractility, they usually die from...
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side effects
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An IABP rapidly shuttles helium gas in and out of the balloon, which is located in the ______. The balloon is inflated at the onset of cardiac _____ and deflated at the onset of _____ to improve coronary perfusion
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descending aorta, inflated during diastole, deflated during systole
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During systole, an IABP deflates rapidly to cause a sudden decr in ______ to augment LV ejection.
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afterload
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IABPs are synced to _____ to set them up, and BP increases when the balloon is _____.
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EKG, inflated
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You cannot use _____ in a bradycardic pt with a denervated transplanted heart. Instead you must use ____.
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no atropine,
use epi instead (beta adrenergic agonists) |
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What are the effects of general anesthesia on heart failure pts?
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- narcotics decr sympathetic stim/tone
- positive pressure ventilation and PEEP aid LV ejection and decr afterload - on a vent, lungs squeeze heart to aid LV ejection |
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What are the effects of regional anesthesia in heart failure pts?
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decr systemic vascular resistance (afterload) may incr CO
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The transplanted heart is ______, and is _____ dependent.
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denervated, preload dependent
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The heart is a ____ chamber within a _____ Chamber.
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pressurized within pressurized!
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LV pressure - intrathoracic pressure =
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LV transmural pressure
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Positive swings in intrathoracic pressure result in
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a decrease in LV transmural pressure -- easier for heart to eject
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Negative swings in intrathoracic pressure result in
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an increase in LV transmural pressure -- harder for heart to eject
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Cardiomyopathies are a heterogeneous group of diseases of the myocardium associated with ____ and/or _____ dysfunction that usually (but not invariably) exhibit inappropriate ______ hypertrophy or dilation du to a variety of causes that are frequently genetic.
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mechanical and/or electrical dysfunction, ventricular
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_______ either are confined to the heart or are part of generalized systemic disorder, often leading to cardiovascular death or progressive heart failure- related disability.
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Cardiomyopathies
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What is the difference between primary and secondary cardiomyopathy?
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primary- confined to heart muscle
secondary- part of multiorgan disease |
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What are the types of primary cardiomyopathy?
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- genetic
- mixed - acquired |
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What are the types of secondary cardiomyopathy?
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- infiltrative (amyloidosis)
- storage - toxic - inflammatory processes - endomyocardial - endocrine - neuromuscular - autoimmune |
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Hypertrophic cardiomyopathy is a ________ trait, involving hypertrophy of ____ and _____.
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autosomal dominant trait,
hypertrophy of septum and anterolateral LV free wall |
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Describe the dynamic LV outflow obstruction of hypertrophic cardiomyopathy.
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the harder the heart works, the worse the flow, because the valve gets sucked into the ventricle and valve leaks - common in athletes
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Hypertrophic cardiomyopathy results in ____ movement of the mitral valve during systole.
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anterior
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Mitral regurg, diastolic dysfunction, myocardial ischemia, and dysrhythmias are all symptomatic of what type of cardiomyopathy?
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hypertrophic
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Describe systolic anterior motion (SAM).
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blood leaks back through mitral valve (mitral regurg), mitral valve presses against septum causing obstruction to blood flow ---> leads to SAM
The LV outflow tract becomes very narrow, close to the anterior leaflet of the mitral valve. Due to the bernoulli principle, with high velocity through narrow area --> causes leaflet to be sucked into LV outflow tract, leads to mitral regurg and sudden decr in CO because blood isn't leaving the heart |
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What factors may increase left ventricular outflow tract obstruction?
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-incr contractility (B agonist, digitalis)
-decr preload -decr afterload |
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What factors may decrease left ventricular outflow tract obstruction?
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-decreased contractility (B blockers, anesthetics, ca channel blockers)
-incr preload -incr afterload best to keep heart optimally filled w afterload normal or high |
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Hypertrophic cardiomyopathy is usually ______, but patients may have angina relieved by _____.
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asymptomatic, lying down
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In some circumstances, hypertrophic cardiomyopathy may present as sudden ____.
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death
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In patients with hypertrophic cardiomyopathy, the murmur of MR may be increased by ______ because it causes a drop in preload and venous return.
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valsalva
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What are the medical and surgical treatment options of hypertrophic cardiomyopathy?
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- medical: beta blockers, Ca channel blockers
- surgical: septalplasty to make larger LV outflow tract |
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What are the anesthesia management goals of hypertrophic cardiomyopathy?
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- minimize LV outflow tract obstruction
- avoid sympathetic stimulation, hypotension and hypovolemia - maintain sinus rhythm |
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What effects do anesthetics have on contractility?
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- depr contractility by decr Ca entry into cells
- halothane (like inhaled beta blocker, potent negative inotrope) and enflurane have most negative inotropic effects - N20 and ketamine - minimal effects - local anesthetics, esp bupivicaine/ropivicaine/tetracaine cause myocardial depr |
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Primary dilated cardiomyopathy is also referred to as
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idiopathic cardiomyopathy
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The etiology of dilated cardiomyopathy may be ____ or ____.
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genetic, infectious
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Secondary types of dilated cardiomyopathy have similar _____ to primary types.
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clinical appearance
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Symptoms of dilated cardiomyopathy
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heart failure, dysrhythmia, embolization, low CO, stasis, mural thrombi, high CVA risk
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Peripartum cardiomyopathy carries a risk of ____ % mortality within 3 mo of delivery, and occurs in 1 out of every ____ Births.
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25-50%, 3000-4000
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Risk factors for peripartum cardiomyopathy
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obesity
multiparity advanced maternal age preeclampsia afroamerican |
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What are the possible etiologies of peripartum cardiomyopathy?
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viral, autoimmune, maladaptive response to hemodynamic effects of pregnancy
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Peripartum cardiomyopathy is an enlargement of the ___ Due to _______.
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left ventricle due to dilated cardiomyopathy
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What are the 3 types of secondary cardiomyopathies with restrictive physiology?
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1. myocardial infiltration: causes severe diastolic dysfunction, very stiff, can't relax
2. amyloidosis: classic example 3. infiltrative diseases: hemochromatosis, sarcoidosis, carcinoid |
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The symptoms of secondary cardiomyopathies with restrictive physiology include ____ and ____.
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heart failure, afib
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An echocardiogram of a pt w secondary restrictive cardiomyopathy reveals
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normal systolic function, severe diastolic function
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With pts in secondary restrictive cardiomyopathy, it is important to maintain ____ and _____.
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sinus rhythm, preload
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The diastolic function of less compliant hearts exhibits ______ end diastolic pressure and volume.
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higher than normal
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The diastolic function of more compliant hearts exhibits ____ end diastolic pressure and volume.
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lower than normal
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_____ dilatation is seen in diseases that induce pulmonary HTN, which include...
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RV dilatation,
COPD, OSA, restrictive lung disease |
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The other name for cor pulmonale is
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pulmonary HTN
incr BP and resistance in lungs leading to R sided Heart failure |
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OSA is characterized by ____ Retention, _____ vasoconstriction, and the heart having to pump against elevated pulm artery pressures, leading to ____ failure.
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CO2 retention, Pulm vasoconstriction, R heart failure
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_____ is essential to improving prognosis of cor pulmonale.
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O2 therapy
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For pts with prosthetic heart valves, they may have to discontinue ____ prior to surgery, and carry a greater risk of ___ and ____.
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anticoagulation, thromboembolism and bacterial endocarditis
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In ______, which is commonly caused by rheumatic heart disease, the ____ is not affected.
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mitral stenosis, LV not affected
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In mitral stenosis, _____ growing on valves makes them immobile/fixed, leading to poor ____ because there is only a pinhole for the L atria to flow into the LV. This results in _____ enlargement.
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calcium, poor opening, L atrial enlargement
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In mitral stenosis, there is a mechanical obstruction to ____ filling. This leads to incr ____ volume and pressure, with a subsequent pressure overload of the R ventricle. Mitral stenosis may then progress to _____.
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LV filling, incr L atrial vol and pres., pulmonary edema
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Mitral stenosis is treated with diuretics because ...
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excess volume can end up in pulmonary circulation
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Mitral stenosis requires good control of afib because...
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you need a good atrial kick to prevent congestion
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It is important to control _____ and provide _____ in mitral stenosis.
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control HR, provide anticoagulation
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The goal HR in valvular disease is
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70
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What are the anesthetic techniques for pts w mitral stenosis?
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- avoid ketamine (tachycardia, heart filling occurs at expense of diastole, less filling when tachy)
- maintain HR control - avoid vol overload (tberg can cause pulm edema) - avoid incr pulm vascular resistance (hypercarbia and hypoxia) |
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Hypercarbia and hypoxia both cause this vascular change in the lungs
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pulmonary vasoconstriction
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Mitral regurgiation is (more/less) amenable to surgery than mitral stenosis.
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less
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The _____ support leaflets from opening inappropriately.
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chordae
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Mitral regurg is a ____ valvular disease with ruptured ______, caused by....
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ischemic, ruptured chordae
caused by endocarditis, cardiomyopathy, rheumatic illness |
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Mitral regurgitation leads to ______ stroke volume and C.O.
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decreased
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Mitral regurgitation is associated with ____ overload of the LV.
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volume overload
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What effect does mitral regurgitation have on the L atrium?
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L atrial enlargement and afib -- dilation interrupts conductivity
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When L atrial enlargement can no longer compensate for mitral regurgitation, _____ ensues.
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pulmonary edema
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The regurgitant fraction in mitral regurg is affected by...
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heart rate and pressure gradient across mitral valve.
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What are the diagnostic criteria for mitral regurgitation?
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- holosystolic apical murmur radiating to axilla
- LVH and cardiomegaly on CXR - echocardiogram |
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What are the anesthesia strategies indicated for mitral regurgitation?
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- prevent bradycardia
- prevent incr SVR - minimize myocardial depr |
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This is the most common type of valvular disease, affecting ___ % of the population.
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mitral valve prolapse, 1-2.5%
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What are the auscultatory sounds of mitral valve prolapse?
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midsystolic click, late systolic murmur
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What diseases are associated with mitral valve prolapse?
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- marfan's syndrome
- SLE - thyrotoxicosis - rheumatic carditis |
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Mitral valve prolapse is usually benign, but could cause...
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- embolism
- dysrhythmia -death |
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Do mitral valve prolapse pts require abx prophylaxis?
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- if regurg present
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____ is a calcification of aortic leaflets during aging, or the presence of a bicuspid aortic valve.
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aortic stenosis
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In aortic stenosis, obstruction of LV output leads to ______.
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LV pressure overload (pinhole opening at aortic valve between LV and aorta)
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In aortic stenosis, the LV tries to compensate with...
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concentric LV hypertrophy (hypertrophy will result with any fixed mechanical obstruction)
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What are the classic symtpoms of aortic stenosis?
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angina, syncope, dyspnea on exertion
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What are the diagnostic criteria for severe aortic stenosis?
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- transvalvular gradient 50 mmHg
- peak pressure gradient 80 mmHg - aortic valve area less than 0.8 cm^2 |
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In managing aortic stenosis during anesthesia, there exists a high risk of major perioperative ____ complications. Therefore, it is important to maintain _____ because _____ is very important to function.
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cardiac complications, maintain sinus rhythm, atrial kick is very important
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What is the ideal HR for aortic stenosis pts during anesthesia?
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70! avoid brady/tachycardia
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Why is it crucial to avoid hypotension in aortic stenosis pts?
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hypertrophied hearts are harder to perfuse, loss of preload leads to decr CO
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If you need to restore BP and contractility during a case in a pt w aortic stenosis, it is important not to use...
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ephedrine or phenylephrine! use epinephrine instead to restore BP and incr contractility, because you need a kick and a squeeze
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In aortic stenosis it is important to avoid hypovolemia so that you can maintain adequate ____.
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preload
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___ is the failure of the aortic valve leaflet's coaptation (closing) due to primary valve disease.
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aortic regurgitation
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What are the causes of aortic regurgitation?
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- endocarditis
- rheumatic fever - bicuspid aortic valve |
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Aortic regurgitation may result from abnormalities of the aortic root, as in the following conditions....
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idiopathic, HTN, syphilis, connective tissue disorder, ankylosing spondylitis
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Aortic regurg leads to a decr in CO due to
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flow back into the LV during diastole
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Aortic regurg leads to ___ and ___ overload of the LV.
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pressure and volume
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The regurgitant fraction in aortic regurgitation is affected by ...
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HR and pressure gradient across the aortic valve
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Over time, aortic regurg causes the ____ to fail and ____ develops.
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LV fails, Pulm edema
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In acute aortic regurg, ____ and ___ may occur quickly.
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coronary ischemia, CHF
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What are the 2 primary mgmt techniques for pt with aortic regurg?
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- vasodilator therapy
- valve replacement |
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What are the anesthesia strategies for a pt with aortic regurg?
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- maintain forward stroke volume
- keep HR above 80 - avoid incr in SVR - minimze myocardial depr |
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What are the causes of tricuspid regurg?
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- annular dilation due to RV enlargement or pulm HTN
- endocarditis - rheumatic heart disease |
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What are the anesthesia strategies for a pt in tricuspid regurg?
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- maintain preload
- beware of R to L shunting across PFO, high R atrial pressures lead to shunting to L heart without traveling first through lungs -- leads to hypoxia |
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Systemic HTN is categorized by a BP reading of greater than ___ on 2 occasions. Only ___% of americans are adequately treated for their HTN.
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140/90, 30%
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HTN is more common in _____ and is a major risk factor for...
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afroamericans,
CAD, CHF, CVA, ESRD |
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Greater than 95% of cases of HTN are ______, occurring with familial incidence.
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essential HTN
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In essential HTN, there is an incr _____ activity, and an overproduction of _____.
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SNS activity,
overprod. of Na-retaining hormones and vasoconstrictors, renin |
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Essential HTN pts often have deficiencies of endogenous ______ such as ____.
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vasodilators, NO
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____ and ____ are often seen comorbidities in essential HTN pts.
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DM and obesity
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The final common pathway of essential HTN is _______ Retention, leading to .....
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salt and water retention,
incr vol and BP |
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Essential HTN can also be caused by _____ abuse and obstructive ______.
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etoh and tobacco abuse, OSA
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Metabolic syndrome is comprise of...
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HTN, insulin resistance, dyslipidemia, obesity
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What are the long term effects of poor BP control?
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CAD, CHF, CVA, PVD, ESRD
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Less than 5% of cases are considered secondary HTN, and the usual cause is...
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renal artery stenosis
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Other possible causes of secondary HTN besides renal artery stenosis include...
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hyperaldosteronism, pheochromocytoma, cushing's syndrome, pregnancy-induced HTN,, aortic coarctation, aging-associated
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Treatment of HTN includes ____ modification, and pharmacologic treatment that may include...
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lifestyle mod.,
thiazide diuretics, ACE inhibitors (if have CHF), beta blockers (if have CAD), ARBs (if have CHF, DM, renal disease), aldosterone antagonist (if have MI, CHF), Ca channel blockers (if have CAD and DM) |
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____ are the first line of drug therapy in HTN
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thiazide diuretics
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HTN crisis is classified as a BP greater than ____, and is better tolerated in pts with ____.
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>180/120,
chronic HTN |
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Hypertensive emergency can lead to target organ damage, including...
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- encephalopathy
- pulm edema - angina - aortic dissection - in pregs, DBP over 109 is an emergency |
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When treating HTN crises, you should avoid _____ drops in BP, and lower BP by ___% in the first hour.
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precipitous, 20%
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This condition has no target organ damage in HTN, but the pt may experience headache, epistaxis or anxiety, and is treatable in some cases with oral meds.
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HTN urgency
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In HTN crisis, how is encephalopathy treated?
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nitroprusside (Very potent, narrow margin of safety), nicardipine, fenoldopam, labetalol
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In HTN crisis, how is cardiac ischemia treated?
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NTG (venodilator, dilates coronary arteries)
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In HTN crisis, how is pulm edema treated?
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nitroprusside, NTG, fenoldopam
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In HTN crisis, how is renal insufficiency treated?
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fenoldopam, nicardipine
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In HTN crisis, how is preeclampsia treated?
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methyldopa (direct acting vasodilator), hydralazine, mag sulfate, labetalol, nicardipine
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In HTN crisis, how are pheochromocytoma pts treated?
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phentolamine, phenoxybenzamine, propranolol
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In HTN crisis, how are cocaine ingestion pts treated?
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NTG, nitropruside, phentolamine
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What are anesthesia strategies for pts with HTN?
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- control BP prior to surgery
- no evidence that complications incr w DBP up to 110 mmHg - "White Coat syndrome"- exaggerated BP response to laryngoscopy or periop myocardial ischemia - HTN pts presumed to have CAD until proven otherwise |
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Hypotension after induction is more common in pts taking what kind of drugs?
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- ace inhibitors or ARBs
risk of hypotension reduced if meds discontinued day prior to OR |
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______ is the essential action of hypovolemia.
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hemodynamic instability
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Preop eval of HTN pts should include
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- determine adequacy of pre op BP control
- review meds - eval for evidence of end organ damage - continue BP meds periop. |
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Induction and maintenance techniques for HTN pts include...
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- anticipate exaggerated response
- quick laryngoscopy - balanced anesthetic technique - monitor leads 2 and 5 for myocardial ischemia |
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Post op mgmt of HTN pts should anticipate ____ and continue _____. It is important to monitor for ____ function.
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HTN, continue BP meds, monitor end-organ fcn
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If meds that affect ANS (B blockers and Clonidine) are abruptly discontinued, then _____ can occur. However _____ meds are not assoc w rebound HTN.
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rebound HTN, ace inhibitors
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What are the 3 BP control systems?
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SNS, vasopressin system, RAAS
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After induction of anesthesia, pts on ace inhibitors rely on their ____ system. ____ is key to maintaining BP.
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vasopressin system, intravascular volume
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Why is it a good idea to discontinue ACE inhibitors 24-48 hrs prior to OR?
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less intraop hypotension, risk of loss of BP control
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What is normal PA pressure?
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18-25/6-10 mmHg
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What is normal PA MAP?
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12-16 mmHg
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In primary pulmonary HTN, PA mean pressure is >
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25 mmHg
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Idiopathic primary pulm artery HTN occurs in ___ Cases per million, and it has ____ inheritance in 10% of cases.
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1-2, autosomal dominant
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What are the s/s of primary PA HTN?
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dyspnea, fatigue, low CO, abdominal distension (Due to RV failure, ascites), "like aortic stenosis of the RV"
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How is primary PA HTN diagnosed?
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- pulm catheterization
- vasodilator test (prostacyclin) - echocardiography |
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In primary PA HTN, there is increased RV Wall stress, leading to ___ and ___, with decreased RV ____.
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hypertrophy, dilatation, stroke volume
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In primary PA HTN, annular dilatation of the ____ valve leads to regurg, and pulmonary insufficiency from ____ dilation.
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tricuspid, pulmonary artery
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Right to left shunting through a patent ____ occurs because tricuspid regurg increases _____ pressures, shunting blood across heart without first oxygenating it.
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foramen ovale, R atrial pressures
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Why does hypoxemia occur as a result of PA HTN?
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fixed cardiac output leads to inr O2 extraction w exertion, incr VQ mismatch
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The baseline hypoxemia that occurs with PA HTN is made even worse during episodes of hypoxia and hypercarbia, because...
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these both cause vasoconstriction, making RV performance worse
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What are the treatment strategies for primary PA HTN?
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- O2
- anticoagulation (due to risk of mural thrombi formation in RV) - diuretics - Ca channel blockers - Phosphodiesterase inhibitors (sildenafil, rivashio) - inhaled NO (dilates pulm vasculature) - prostacyclins - endothelin receptor antagonists (Bosentan) |
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What are the anesthesia considerations for a pt with primary PA HTN?
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- incr risk of periop morbidity and mortality due to RV failure, dysrhythmia, and embolism
- avoid hypoxia, acidosis, hypercarbia!! - maintain intravasc. volume - maintain sinus rhythm (avoid bradycardia) - avoid negative inotropes (propofol can cause acute RV failure - use etomidate instead!) - avoid hypotension and optimize preload - use controlled ventillation to avoid hyperCO2 (spontaneous modes blunt hypercarbic response to stimulate blowing off CO2) - PEEP incr pulm vascular resistance (use 5) |
