Perfusions: MI Flashcards
What are the most common causes of atherosclerosis?
reduced flow due to:
high levels of LDL, toxins; atheromas
What is ischemia?
Oxygen supply is inadequate to meet metabolic needs
What are the 3 categories of anginas?
- stable
- unstable
- prinzmetal (variant)
What does ischemia do to the heart and body?
- causes injury to tissues
- it is REVERSIBLE
- causes chest pain
When may a scar be seen from ischemia?
It may not be seen until the third week so the patient will be sensitive to oxygen demands
Define angina
Recurrent chest pain associated with reversible damage to the myocardium
Describe an infarction
IRREVERSIBLE damage to the heart muscle causing necrosis. If extensive, the heart may fail.
What are the AHA recommendations for people experiencing chest pain?
- an individual with unknown chest pain should seek emergency care if chest pain is not relieved by 3 NTG tablets over a 10 min period
- In a person with previously unrecognized coronary disease, the persistence of suspicious chest pain for 2 min or longer may be an indication for emergency medical assistance
What is acute coronary syndrome?
When coronary blood flow is significantly reduced, but not fully occluded.
What can cause acute coronary syndrome?
- rupture or erosion of atherosclerotic plaque
- Coronary artery spasm
- Progressive vessel obstruction
- Inflammation of coronary artery
- Increase in myocardial oxygen demand and/or decrease in supply
What is AMI?
Acute myocardial infarction- blood flow to a portion of cardiac muscle is COMPLETELY blocked causing prolonged tissue ischemia and irreversible cell damage
How are acute myocardial infarctions usually described?
By location of the heart that was damaged.
EX: occlusion of the left anterior descending artery= anterior MI
Left circumflex artery= lateral MI
What drug toxicity can cause an acute MI?
cocaine
What are the nonmodifiable risk factors of an acute MI?
- age
- male gender
- family hx
What are the modifiable risk factors for an acute MI?
- hypertension
- DM
- Hyperlipidemia
- cigarette smoking
- obesity, diet
- physical inactivity
- stress
What are some emerging risk factors for acute MI?
- elevated levels of homocysteine
- inflammatory processes
- metabolic syndrome
What are the risk factors of an acute MI unique to women?
- premature menopause
- oral contraceptive use
- hormone replacement therapy
What are the manifestations of acute coronary syndrome?
- chest pain (substernal or epigastric)
- pain that radiates from the neck, left shoulder, left arm
- pain may occur at rest
- typically lasts longer than 10-20 min
- dyspnea, diaphoresis, pallor, cool skin
- tachycardia and hypotension
What are the manifestations of acute myocardial infarction?
- continuous chest pain, more severe than angina
- onset sudden, not associated with activity
- described as crushing, severe, pressure, heaviness, squeezing
- begins at the center of the chest, then radiates
- lasts more than 15-20 min
- women and older adults have atypical symptoms
- tachycardia, tachypnea, dyspnea
- nausea/vomiting
- anxiety, sweating, cool, mottled skin
- HTN, or hypotension
- Palpitations/dysrhythmias
- signs of left HF
- decreased LOC/orthopnea
- leukocyte count up to 15-20k due to cell damage
- increased sed rate/ increased temp
What are the manifestations of angina pain?
- chest pain typically preceded by an identifiable event
- tight, squeezing, heavy pressure, or constricting sensation
- begins beneath the sternum and radiates
- women often usually have atypical symptoms
What are some complications of acute myocardial infarction?
- dysrhythmias
- pump failure
- cardiogenic shock
- infarct extension
- structural defects
- pericarditis
What are the treatment goals for acute myocardial syndrome and infarction?
- relieve chest pain
- reduce the extent of myocardial damage
- maintain cardiovascular stability
- decrease cardiac workload
- prevent complications
What diagnostic tests may be used to monitor and diagnose acute myocardial syndrome or infarction?
- C-reactive protein
- Ankle-brachial blood pressure index
- exercise ECG testing
- electron beam computed tomography
- myocardial perfusion imaging
- cardiac markers
What diagnostic tests are cardiac markers?
- creatine kinase
- CK-MB
- Troponins
- myoglobin
- CBC
- ABGs
What is CPK and how long does it take to work?
Creatinine phosphokinase
4-6 hour onset; 12-24 hour peak; 3-4 day duration
What is LDH and how long does it take for it to work?
Lactic dehydrogenase
8-12 hour onset; 24-48 peak; 10-14 day duration
LDH1 (primary heart)> LDH2 is significant for MI
note the time drawn, compared to the onset of chest pain and values
What are some significant EKG changes that you would see in an MI?
- elevated ST segment (shows ischemia) w/in the first few hours
- Inverted T wave (seen 8-24 hours post-MI)
- both return to normal w/in 2-3 months
- pronounced U wave always
What are the best ways to prevent acute coronary syndrome or infarction in the future?
- stop smoking
- good diet (reduce saturated fat/cholesterol, Lower LDL level, increase intake soluble fiber, moderate alcohol intake)
- weight reduction if needed
- exercise each week ( at least 30 min moderate-intensity 5-6 days/week; 60-90 min of moderate-intensity daily is recommended)
- maintain BP <140/90
- diabetes: weight loss, reduce fat intake, blood glucose management
What medications are used to lower cholesterol?
- Statins
- Nicotinic acid
- bile acid sequestrants
- fibrates
What are some other medications for acute coronary syndrome?
- cholesterol meds
- aspirin
- ACE inhibitors
- angiotensin receptor blockers
What meds are used for angina?
- nitrates
- beta-blocker
- calcium-channel blockers
- aspirin
what conditions are contraindicated with beta-blockers?
asthma and severe COPD
What conditions should you be cautious with when giving calcium-channel blockers?
Dysrhythmias/heart failure
What meds are used to treat MI?
- aspirin
- analgesics
- Fibrinolytics
- antidysrhythmics
Give some examples of analgesics used to treat MI
- sublingual nitroglycerin
- morphine sulfate
- IV nitroglycerin
What is the acronym for emergency treatment with MI?
MONA Morphine Oxygen Nitroglycerin Aspirin
What does nitroglycerin do to the body and why can it be used for MI?
- relaxes vascular smooth muscle
- Dilates large coronary arteries, antagonizes vasospasm, increases coronary collateral blood flow to the ischemia heart muscle
- Reduces left ventricular filling pressures
What are the side effects of nitroglycerin?
frequently causes headaches and a reduction in blood pressure
What route is nitroglycerin given?
sublingual, intravenous
What do beta-blockers do to the body and why is it sometimes used for an MI?
- decreases HR, BP, and myocardial contractility thus O2 consumption
- it is used for emergency use for v-tach, recurrent v-fib, and SVTs
What should a nurse beware of with Beta-blockers?
they may precipitate CHF, Bronchospasms, and hypotension
What do calcium channel blockers do to the body and what are they most helpful with?
- dilate smooth muscle walls of coronary arterioles and decrease O2 demand
- helps with angina
What do most CCBs end in?
-dipine
What IV drugs can be used for cardiac decompensation?
dopamine and dobutamine
Why is dopamine used for cardiac decompensation and what are its side effects?
1. increases urine (due to renal vasodilation) Side effects: 1. increased HR 2. ectopy and pulse pressure 3. extravasation= necrotic tissue
Why is dobutamine used for cardiac decompensation?
- increases urine (due to increased cardiac output)
- no renal vasodilation
- no ectopy
What puts people at risk for toxicity with Digitalis?
- age
- renal impairment
- high serum Ca++
- Low serum K+
- liver impairment
- acute hypoxia
- recent MI
What can cause digitalis toxicity?
- bradycardia, nausea
2. arrhythmias: atrial, junctional, and ventricular
What are the treatments for digitalis toxicity?
- hod dig, call Dr.
- PVC’s- use antidysrhythmic meds
- V-tach- use cardioversion
Why is digitalis (digoxin) used for MI?
Increases contractility and decreases the workload
What thrombolytic agents are used for MI, angina, or coronary syndrome?
- streptokinase
- TPA (activase) Tissue-type plasminogen activator
- Reteplase
What nursing considerations should be remembered when giving thrombolytic agents?
- before giving: start as many functional large-bore IV sites as feasible/obtain lab draws
- Watch for reperfusion arrhythmias: Incidents have occurred where an individual received t-PA and then left via ambulance to a major hospital just to die in transport secondary to arrhythmias
- Once you give the meds you MAY NOT puncture the patient again! (they run the risk of death from hemorrhage)
What does absolute mean in regards to thrombolytic agents?
ABSOLUTELY do not give thrombolytics with these diseases or problems
What disease and problems are absolute in thrombolytic therapy?
- malignant intracranial neoplasm
- prior intracranial bleeding
- active internal bleeding
- aneurysm
- Arteriovenous malformation
- ischemic stroke within 3 months
What does relative mean in regards to thrombolytic agents?
Means to weigh the risks vs the benefits before giving thrombolytics
What diseases and problems are relative in thrombolytic therapy?
- traumatic or prolonged CPR or major surgery
- allergic reactions to agents
- pregnancy
- active peptic ulcer
- Current use of anticoagulants
- higher the INR, the higher the risk of bleeding
What clinical therapies are used for MI?
- intensive coronary care unite first 24-48 hours
- bed rest first 12 hours with bedside commode
- Oxygen 2-5 L/min nasal cannula
- liquid diet, progress to low fat/cholesterol/sodium
- limit caffeine, hot foods, cold foods
- revascularization procedures
- invasive procedures
What are some revascularization procedures that are often used for MI?
- percutaneous coronary revascularization
- coronary artery bypass grafting
- minimally invasive coronary artery surgery
- transmyocardial laser revascularization
What invasive procedures are often used for an MI?
- intra-aortic balloon pump
2. ventricular assist devices
What are the goals for treating an MI?
- reduce myocardial oxygen demand
- improve oxygen supply
- usually managed in community settings
What are the assessments needed for Acute coronary syndrome, Angina, and AMI?
- health Hx: current manifestations, current lifestyle factors, hx of heart disease
- physical examination: current weight/BMI, blood pressure, peripheral pulses
How would a nurse promote balanced nutrition with acute coronary syndrome, angina, and AMI?
- assess intake and food intake
- discuss dietary recommendations
- refer to dietitian
- encourage the use of fad diets
- Encourage weight loss goals
How would a nurse promote effective health maintenance for acute coronary syndrome, angina, and AMI?
- discuss risk factors
- discuss benefits of smoking cessation
- Help identify sources of support: physical, psychosocial
- Discuss benefits of regular exercise
- teach about meds
How would a nurse help to manage acute pain for acute coronary syndrome, angina, and AMI?
- assess for pain
- administer O2
- promote physical, psychological rest
- use IV nitroglycerin
- administer morphine sulfate
How would a nurse monitor tissue perfusion for acute coronary syndrome, angina, and AMI?
- assess VS
- Assess LOC
- auscultate heart and lung sounds
- Monitor ECG
- Monitor oxygen saturation levels
- Administer meds
- Obtain lab values
- plan for hemodynamic monitoring
How would a nurse promote effective coping for acute coronary syndrome, angina, and AMI?
- establish an environment of caring/trust
- accept denial as coping mechanisms
- note aggressive behaviors
- Help identify coping skills
- promote decision making
- provide privacy for client/family
How would a nurse help to manage fear for acute coronary syndrome, angina, and AMI?
- note verbal and nonverbal signs of fear
- acknowledge the client’s perception of the situation
- encourage questions
- encourage self-care
- give antianxiety meds
- teach nonpharmacologic methods of stress reduction
How would a nurse promote effective cardiac perfusion for acute coronary syndrome, angina, and AMI?
- keep nitroglycerin at the bedside
- start oxygen
- allow rest between activities
- teach about meds
- Instruct regarding prophylactic SL nitroglycerin
- Encourage exercise
- Refer for smoking cessation
How would a nurse promote effective therapeutic regimen management for acute coronary syndrome, angina, and AMI?
- assess/instruct regarding disease process
- provide written/verbal med instructions
- Stress importance of recognizing chest pain
- Refer for cardiac rehabilitation
What are some complications of MI?
- left ventricular failure
- ventricular dysrhythmias
- pulmonary edema
- cardiogenic shock (the result of LV failure)
- sudden death