Week 7: Chp 28: Diagnostic Imaging Studies for Cardiovascular Function Flashcards
Electrocardiography (ECG)
basic diagnostic assessment that is completed routinely on patients to assess the electrical conduction system of the heart
- identify the presence of dysrhythmias, new or old heart muscle damage, electrolyte abnormalities, and/ or cardiac hypertrophy
- done by placing 10 electrodes on specific parts of the body
ECG Placement
V1: 4th intercostal space, just to the right of the sternum
V2: 4th intercostal space, just to the left of the sternum
V4: on the midclavicular line and 5th intercostal space
V6: on the midaxillary line, horizontal with V4
V5: between V6 and V4 on the anterior axillary line
V3: between V4 and V2
ECG: Nursing Implications
- patient can be resting or ambulatory
- resting is done supine and quiet
- skin must be clean, dry, and as free from hair as possible
- ambulatory (holter monitoring); can be done continuously over several days while the patient maintains normal activities; in this way symptoms such as chest pain, SOB, or syncope may e correlated with rhythm changes
Radiology: Chest x-ray (CXR)
general screening tool that provides information about size, shape, and position of the heart
- CXR can not diagnose heart disease by itself but can highlight complications such as cardiac enlargement or pulmonary congestion
- pneumonia, pneumothorax, and other primary lung disorders are diagnosed via CXR
- also used o confirm placement of central venous catheters, endotracheal tubes, and chest tubes
Chest x-ray: Nursing Implications
- hospital gown replaces any clothing worn on the upper body, especially a bra
- patient is instructed to hold their breath for several seconds while the film is obtained, minimizing movement, and improving the quality and sharpness of x-ray
Echocardiography
uses ultrasound to provide information on the size and pumping function of the heart, blood-volume status, and valve function and integrity
-two types: transthoracic echocardiogram (TTE) and the transesophageal echocardiogram (TEE)
Two Types of Echocardiogram
- transthoracic echo (TTE)
2. transesophageal echo (TEE)
Transesophageal Echo (TEE)
obtained by placing the ultrasound transducer in the patients esophagus
- provides information from the posterior of the heart
- used when complications such as obesity or lung disease may obscure the standard TTE by interfering with the transmission of the ultrasound waves anteriorly
- provides info about the posterior aspect of the heart such as the left atrium
TEE: Nursing Implication
- instructed not to eat or drink for at least 8 hours prior to the procedure
- small sips of water with medications are the exemption
- patients are given sedation for the test, so they should be instructed to have someone with them who can drive them home
Cardiac Stress Testing
done to evaluate heart functioning during times of increased workload
- way to evaluate the functional ability of the heart
- screening tool for cardiovascular disease that may become apparent only when the heart is stressed; symptoms such as chest pain, dizziness, dysrhythmias, or SOB may occur
Regular Stress Testing
- done on a treadmill or stationary bike
- patient is attached to a monitor system
- heart rate, rhythm, and BP are monitored at regular intervals during the exercise
Chemical Stress Testing
done if the patient is unable to exercise because of physical limitations
-cardiac stress is induced with IV administration of a medication such as dobutamine, a medication that stimulates the heart similar to exercise
Isotope or Nuclear Stress Testing
combination of a regular stress test and a chemical stress test
- the chemical is an intravenously injected nuclear isotope tracer such a thallium
- purpose of this test is to visualize areas of poor perfusion in the heart due to blocked arteries
- the isotope is more readily supplied to and picked up by tissues that have adequate perfusion, creating “hot spots” when imaged
- areas of poor perfusion get a lesser supply of the isotope, creating “cold spots”
- imaging is done after exercise and at rest
Another form of isotope used in nuclear stress testing
technetium
- radioisotope becomes bound to damaged tissues, creating hot spots
- imaging is done several hours after injection, allowing renal clearance of medication not accumulated in the damaged cardiac tissue
Cardiac Stress Testing: Nursing Interventions
Patients are instructed to
- not eat or drink for 4 hours prior to the procedure to avoid any nausea that might be associated with heavy exercise
- avoid smoking prior to test
- avoid caffeine prior to the test
- nurse must be prepared for patient decompensation
Cardiac Catheterization
invasive x-ray procedure during which a radiopaque catheter is advanced through an artery or vein to the heart under fluoroscopy in order to evaluate cardiac filling pressures, cardiac output (CO), and valvular function
- right heart catheterization can be done through a suitable vein (femoral, brachial, subclavian); the catheter is advanced to the heart via the inferior or superior vena cava
- left heart catheterization is done through a suitable artery (femoral, brachial, radial); catheter is advanced up through the aorta and into the left heart
Coronary Angiography
primary reason cardiac catheterization is performed
- left-sided cardiac catheterization with the purpose of inspecting the coronary arteries for blockage and determining the necessity of revascularization procedures such as percutaneous coronary intervention or coronary bypass surgery
- done through a technique called cineangiography
- once the catheter is in place, contrast dye is injected that allows visualization of the vessels; multiple consecutive images are obtained, allowing visualization of the dye flowing through the specific arteries being studied, noting any areas of stenosis or blockage
Coronary Angiography is the primary reason for what to be performed?
cardiac catheterization
Coronary Angiography is done through what technique?
cineangiography
-once the catheter is in place, contrast dye is injected that allows visualization of the vessels; multiple consecutive images are obtained, allowing visualization of the dye flowing through the specific arteries being studied, noting any areas of stenosis or blockage
Cardiac Catheterization Risks
- threat of dysrhythmia is always present when inserting a catheter into the heart
- touching the myocardium with the catheter tip frequently causes an extrasystole, or irregular beat
- risk for bleeding, especially when cannulating an artery for the procedure
- risk for infection with any invasive procedure
- myocardial infarction (MI), perforation of the heart or great vessels, and stroke
Cardiac Catheterization and Coronary Angiography: Nursing Interventions Patient Teaching
- fasting 6 to 8 hours prior the procedure
- expected duration and activities to expect (IV insertion, sedation) during procedure
- information regarding potential sensations that may be experienced during the procedure, such as a “hot flash” as the dye is injected or palpitations if dysrhythmias occur
- maintain adequate fluid intake after the procedure
- avoiding strenuous activity until your provider gives the OK to resume normal activities
- monitoring cannula insertion site for bleeding
Cardiac Catheterization Nursing Interventions Pre-Procedure Care
- establish baseline vital signs
- review blood work focusing on renal studies
- complete pre-procedure checklist that includes obtaining height and weight and ensuring patient has been NPO
- administer pre-procedure hydration
- check glucose levels while NPO
- anticipate holding diabetic medications
Cardiac Catheterization Nursing Interventions Intraprocedure
- psychological support for the patient during the procedure to help ease fears
- vigilant cardiac monitoring during the procedure to observe for dysrythmias
- readiness and ability to respond with advanced cardiac life-support interventions should be a lethal dysrhythmia occur
Post-Procedure nursing interventions for cardiac catheterization
- maintain patient on flat bedrest for 2 to 6 hours to prevent stress on the insertion site, which may cause bleeding
- observation of the catheter insertion site for bleeding or hematoma formation
- cardiac monitoring and frequent vital signs
- monitoring the patient for chest pain
- assessing for signs of stroke, such as confusion, weakness, or slurred speech
- monitoring peripheral pulses, color, and temperature in the affected extremity
- monitoring urine output secondary to the osmotic diuresis caused by the contrast dye
- maintaining sufficient oral and/or IV fluid intake to ensure renal clearance of the dye and to maintain adequate hydration status
- obtain blood work to assess renal function, hemoglobin/ hematocrit, and coagulation studies
Age-related changes
physical deconditioning can result in:
- atrophy of the left ventricle
- decreased elasticity of the aorta
- rigidity of the valves
- stenosis of the heart valves, stiffening of the arterial walls, and increased fibrosis of the heart chambers, leading to hypertension
- formation of atherosclerotic plaques and narrowing of the arterial walls, leading to increased risk of thrombosis and stroke
