MS2 - Cardiac - Concepts Flashcards
What chest x-ray shows for cardiac
Is heart enlarged?
Ejection fraction
% of blood pumped out of left ventricle with each contraction
- EF < 50% - heart failure
- EF < 40% - medicare report - CMS (core measures)
Therapeutic Lifestyle Changes Diet
Total fat (incl. sat fat calories): 25-35% of total daily calories
Saturated fat: <200 mg
Plant stanols or sterols (e.g., margarines, nuts, seeds): 2 g
Dietary fiber: 10-25 g of soluble fiber
Total calories: Only enough calories to reach or maintain a healthy weight
Physical activity: at least 30 min of moderate-intensity activity on most, and preferably, all days of the week
Echocardiogram shows?
Structures and blood flow
What is preload?
- work or load imposed on the heart before contraction begins
- amount of blood returning to the heart for the heart to manage
What is afterload?
- pressure that left ventricle must exert to get the blood out of the heart and into the aorta
- higher afterload -> harder for heart to eject blood -> lower stroke volume
- increased afterload and preload can increase blood pressure
Pulse pressure
- Difference between the systolic and diastolic pressures
- force that heart generates each time it contracts
Optimum LDL:HDL ratio
Below 3:1 (or, in whole numbers, 3.0)
Optimum ratio of total cholesterol to HDL
Optimum ratio is below 3.5:1, but goal is to keep ratio below 5:1
Troponin I and T
- Used as a marker to detect MI
- Rises 4-6 hours after injury
- Peaks in 10-24 hours
- Troponin I stays elevated for 4-7 days
- Troponin T stays elevated for 10-14 days
CK-MB
- Marker that can be used to detect MI but tends to not be used
- Rises later and returns to normal sooner than troponin
- Rises in 6 hours
- Peaks in 18 hours
- Returns to normal in 24-36
Risk factors for heart disease
Nonmodifiable: Age>65 Gender: Male (over 65, same risk for both) Ethnicity (white) Genetics
Modifiable: High serum lipids (>200 at risk and should be treated) Hypertension Smoking Inactivity Obesity Stress (type A personality more likely) Diabetes Metabolic syndrome
Interventions to reduce risk factors for heart disease
Nutritional therapy - cholesterol <7% daily calories, 10-25 g of soluble fiber
Reduce salt intake (strict salt restriction more for HTN)
More small, frequent meals
At least 30 min of physical activity daily
Seek help for stress - stress reduction techniques
Avoid tobacco
Diabetes management
Goal BMI 18.5 to 24.9
Drugs for lipids, anti-platelet therapy (statins - e.g. simvastin, atrovastin; beta blockers, ACE inhibitors)
Symptoms of an MI – including in women and elderly
Pain - severe, immobilizing chest pain
- Not relieved by rest, position change, or nitrate administration is hallmark of MI
- Persistent and unlike any other pain - heaviness, pressure, tightness, burning, constriction, or crushing
- Common locations: substernal, retrosternal, epigastric (pt may think epigastric pain is indigestion) - pain may radiate to neck, lower jaw, and arms or back
- Can happen any time, but usually early morning hours
- Last 20+ mins and more severe than anginal pain
Other
- May have “discomfort,” weakness, or shortness of breath
- Some women may experience atypical discomfort, SOB, or fatigue
- Diabetes: silent (asymptomatic) because of cardiac neuropathy, may have dyspnea
- Older: change in mental status (confusion), SOB, pulm edema, dizziness, dysrhythmia
MONA or ONAM and why
O = Oxygen N = Nitroglycerin A = Aspirin M = Morphine
MONA is in order to remember but ONAM is in order given – increase oxygen first, then administer nitrates to vasodilate, then aspirin to decrease platelet aggregation, then morphine to reduce pain and anxiety (which can also decrease O2 demand) - though morphine is usually only given if nitrates don’t work or pt is having anxiety.
Improvement of chest pain in MI
To address pain: NTG, morphine, supplemental O2 as needed to eliminate or reduce chest pain
Relief is pain indicates reperfusion of tissue
Aspirin, heparin
PCI (percutaneous coronary intervention) or thrombolytics or CABG surgery
Post CABG assessments
- Assessing for bleeding (e.g., chest tube drainage, incision sites), hemodynamic monitoring, checking fluid status, replacing electrolytes as needed, and restoring temperature (e.g., warming blankets)
- Postoperative dysrhythmias, specifically atrial dysrhythmias, are common in first 3 days after CABG - postop afib happens 20-50% of pts - B-Adrenergic blockers should be restarted as soon possible
- Caring for surgical sites (chest incision usually closed with Dermabond and does not require dressing)
- Pts may have some cognitive dysfunction - 40% of pts after surgery, can become permanent
- Assessing pain, respiratory complications, and preventing venous thromboembolism
- Older pts, high risk of dysrhythmias, stroke, infection
Difference between angina and a MI
- MI lasts longer, more fatalities, can happen at any time (though usually early morning)
- Serum cardiac markers present in MI
- Can treat angina at home
- Damage reversible with angina, damage permanent with MI
- Nausea more common with MI (due to severe pain)
- Angina more predictable, has precipitating factors (MI precipitated by prolonged ischemia)
Difference between stable and unstable angina
- Chronic stable angina is long-term - can lead to unstable angina (significant change to pattern of angina)
- Unstable angina is unpredictable and an emergency - stable angina is predictable and can be treated at home
- UA increasing frequency, minimal to no exertion - pain is more intense vs chronic stable
- Women’s symptoms for UA may include fatigue (most prominent), SOB, indigestion, anxiety
- Pain for stable not relieved by nitro - wait 5 min, take another, up to 3, then wait 5 and call EMS if pain not relieved or worsens
- Pain for UA - take nitro, wait 5 mins - if not relieved call EMS asap
Cardiac Cath teaching and post-cath nursing care
- Inform patient about feeling of warmth when dye is injected, and possible fluttering sensation of heart as catheter is passed
- Pt may be instructed to cough or take a deep breath when dye is injected, and pt is monitored by ECG throughout procedure
- Pt will remain supine for 8 hours, and cannot flex leg used for procedure
After procedure:
- Frequently assess circulation to extremity used
- Check neurovascular status (E.g. periph pulses, etc)
- Adequate IV and fluids to flush dye - monitor I&O because dye is osmotic
- Give finger foods to eat since they are lying down
- Observe puncture site for hematoma and bleeding
- Place compression device over arterial site to achieve hemostasis if indicated
- Monitor vital signs and ECG
- Assess for hypo or hypertension, dysrhythmias, and signs of pulm emboli
Cardiac Markers for MI
Troponin I and T
- Rises 4-6 hours after injury (2-3 hours newer assays)
- Peaks in 10-24 hours
- cTnI elevated 4-7 days, cTnT 10-14 days
- cTnI Neg 2.3 ng/mL
CK-MB
- Cardiospecific enzyme released in presence of myocardial tissue injury - rises later and lowers sooner vs troponin
- Increase 4-6 hr after MI, peak 18 hr, return to baseline 24-36 hr
- > 4-6% of total creatine kinase (CK) highly indicative of MI
Myoglobin - Protein that is sensitive for myocardial injury - serum concentrations rise 30-60 min after MI Norm ranges: Male: 15.2-91.2 mcg/L Female: 11.1-57.5 mcg/L
Complications of MI
- Dysrhythmias most common - afib (AF) occurs in 20-50% of patients
- Heart failure
- Cardiogenic shock - occurs less often with rapid and early treatment
- Papillary muscle dysfunction (auscultate murmur at cardiac apex) - echocardiogram confirms diagnosis
— papillary muscle rupture rare and life-threatening - causes mitral valve regurgitation –> dyspnea, pulmonary edema, decreased CO - rapid deterioration by patient - treat with nitroprusside (Nipride) and/or IABP therapy, immediate cardiac surgery
Ventricular aneurysm - infarcted myocardial wall is thin and bulges out during contraction - can develop within days, weeks or months
Pericarditis - inflammation of visceral and/or parietal pericardium - may result in cardiac tamponade, decreased ventricular filling and emptying, and HF - occurs 2 or 3 days after an acute MI - sitting in forward position often relieves pain - can also use NSAIDs, aspirin, corticosteroids
Prioritization and Delegation
Cardiac Cath:
LPNs can administer meds before/after procedure, assess neurovascular status for first 15 mins for first hour, check for bleeding at insertion site (Q15 min for first hour), report changes to RN
UAP can take vital signs and report increases/decreases, can report complaints of chest pain, SOB, or other signs of distress. Can assist with oral hygiene, hydration, meals, and toileting.
Side effects of Lasix
- F&E imbalances (hyponatremia, hypokalemia)
- Hypercholesterolemia, hypertriglyderidemia
- Sexual dysfunction
- Hypotension
- Ototoxicity
- Possible allergic reaction if sensitive to sulfa-type drugs