Week 7: Chp 28: Assessment of Cardiovascular Function Flashcards
Major Risk Factors for Cardiovascular Disease (CVD)
- family history of CVD
- diabetes mellitus
- chronic renal disease
- hypertension
- hyperlipidemia
Nonmodifiable risk factors for CVD
demographic data: age, sex, ethnic background
Modifiable risk factors for CVD
- weight
- dietary habits (consumption of fats and sodium)
- alcohol consumption
- smoking history
- sedentary lifestyle
Significant complaints pertinent to heart disease
- presence of chest pain
- difficulty breathing (dyspnea)
- cough
- palpitations
- edema
- fatigue
- syncope
Palpitations ae indicative of what?
abnormal heart rhythms or dysrhthmias
Syncope is indicative of what?
decreased cardiac output resulting from problems with either the mechanical or electrical properties of the heart
Blood Pressure Stages
Normal: SBP <120, DBP <80 Pre-hypertensive: SBP 120-129, DBP <80 Stage 1: SBP 130-139, DBP 80-89 Stage 2: SBP >140, DBP >90 (based on average of two or more readings found two or more times on examination)
Inspection
is done to assess color, capillary refill time, edema, presence of absence or jugular vein distension, and clubbing of fingers or toes
Inspection: Cyanosis
poor perfusion produces a pale gray or bluish color
- in dark-skinned people, cyanosis appears gray
- can be central or peripheral
- central cyanosis appears as blue coloring in the mucous membranes, lips, and tongue.; usually caused by impaired heart or lung function
- peripheral cyanosis, or blue discoloration of the extremities, can be caused by heart or lung failure but may also indicate peripheral vasoconstriction or obstruction
Inspection: Capillary refill time
a return to color within 3 seconds indicates adequate peripheral circulation
-sluggish return may indicate arterial spasm or insufficiency
Inspection: Edema
may be a sign of cardiac or liver issues
- Bilateral lower extremity edema, if not associated with a local injury, indicates venous insufficiency or heart failure
- Unilateral extremity edema, if not associated with a local injury, can indicate a venous or lymphatic obstruction
- identified as pitting or non-pitting; pitting is characterized by an indenting of the skin that remains after pressure has been applied then released
Inspection: Distension of jugular veins
may be present in a patient with a constrictive disease such as pericarditis or cardiac tamponade
- also seen in patients with right ventricular failure, valvular disease, or hypervolemia
- often associated with poor contractile function of the heart that is present in heart failure
Palpation
assessment of skin temperature and pulses
- adequate cardiac output produces warm skin temperatures
- cool or cold temperatures may indicate vasoconstriction, heart failure, or shock
- pulses usually palpated are radial and dorsalis pedis pulse
- strong, palpable pulses indicate adequate cardiac output and good flow through the peripheral vessels
Auscultation
assessment of heart and lung sounds
Heart Sounds
- “lub”, “dub”
- first heart sound, S1, “Lubb”, is the closing of the AV valves. signifies the beginning of ventricular systole
- second heart sound S2, “Dubb”, is the closing of the semilunar valves. signifies the beginning of diastole
Systolic Murmur
caused by valvular disease such as aortic stenosis
-turbulent flow heard
Diastolic Murmur
caused by valvular disease such as aortic or pulmonic regurgitation
-turbulent flow heard
Click
- caused by mitral valve stenosis
- high-pitched sound
Friction Rub
- caused by pericarditis
- harsh, scratching sound
Lung Sounds
- give an indication of both lung and cardiac health
- auscultation of rales, rhonchi, or rubs in the lung fields indicate the presence of fluid
Laboratory Markers as Predictors of Heart Disease: Lipid Panel
includes:
- total cholesterol
- low-density lipoproteins (LDLs)
- high-density lipoproteins (HDLs)
- triglycerides
Cholesterol
lipid necessary for the synthesis of hormones and cell walls
- available through ingestion of animal products (e.g. meat) and through synthesis in the liver
- not soluble in blood, so it combines with proteins to form lipoproteins, LDLs and HDLs, to facilitate transport through the vascular system
Low-Density Lipoproteins (LDLs)
primarily transport cholesterol into the cell but can also deposit it on the walls of the arterial vessels
- normal values: < 100 mg/dL
- elevated levels, greater than 100 mg/dL, are associated with an increased risk of heart disease
High-Density Lipoproteins (HDLs)
protective lipoproteins
- transport cholesterol away from the cells to the liver for excretion
- normal: > 40-60 mg/ dL
- decreased levels, less than 40-60 mg/dL, are a risk factor for heart disease
Total Cholesterol
- includes both LDLs and HDLs
- normal levels: 200 mg/dL or less
- increased levels at risk for atherosclerotic vessel disease
Triglycerides
- lipid
- store unused ingested calories in fat cells, which may be later released as an energy source between meals
- normal: less than 150 mg/dL
- elevated levels, greater than 150 mg/dL, are another risk factor for heart disease
Non-specific predictor markers
- glucose
- homocysteine
- c-reactive protein
- coagulation studies
Non-specific marker: Glucose
- diabetes and hyperglycemia are major risk factors for CVD
- normal: 65-99 mg/dL
Non-specific markers: homocysteine
an amino acid
- increased homocysteine is a risk factor for heart disease
- can damage the lining of arterial walls, causing clot formation
- decreased dietary intake of folic acid and B vitamins is associated with increased levels of homocysteine
Non-specific markers: homocysteine
an amino acid
- increased homocysteine is a risk factor for heart disease
- can damage the lining of arterial walls, causing clot formation
- decreased dietary intake of folic acid and B vitamins is associated with increased levels of homocysteine
- normal: 4.4-10.8 mm/L
Non-specific Markers: C-reactive Protein
- not specific for cardiac disease but used in conjunction with other laboratory tests
- elevated levels reflect increased production of C-reactive protein in the liver secondary to systemic inflammation; inflammation is implicated in the development of atherosclerosis
- normal levels: 0 (only present when inflammation is present)
Non-Specific Markers: Coagulation studies
obtained for screening purposes
- increased platelet and fibrinogen levels are correlated with an increased risk of atherosclerotic heart disease
- prothrombin time, partial thromboplastin time, and international normalized ratio are measured in patients with increased clot formation, such as patients with atrial fibrillation
Nursing Implications: Lipid Panel Lab Test
-lipid panel requires the patient to fast for approximately 8 to 12 hours prior
Coagulation Studies
- Platelets: 150,000-400,000 mc/L
- Fibrinogen Levels: 200-400 mg/dL
- Partial Thromboplastin Time (PTT): 25-35 seconds
- Prothrombin Time: 10-13 seconds
- International Normalized Ratio (INR): <2.0
Laboratory Markers of Acute Cardiac Damage or Injury
include enzymes or proteins that are elevated in response to cellular injury
- Creatinine Kinase myocardial bands (CK-MB)
- Troponin
- Myoglobin
- Brain natriuretic peptide (BNP)
Creatinine Kinase (CK)
general marker of cellular injury
-released from cells in the brain, skeletal muscle, and cardiac tissue after muscle damage has occurred
Creatinine Kinase myocardial bands (CK-MB)
isoenzyme of CK
- marker specific to cardiac tissue
- when myocardial damage occurs, CK-MB is released from the cells
- increased levels can be seen at 3 hours after myocardial damage and can remain elevated for up to 36 hours before returning to normal
- normal: 0-3 ng/mL
Troponin
specific marker of cardiac muscle damage and is the preferred method for diagnosing cardiac injury
- protein released from damaged tissue and can elevate within 4 hours of injury
- stay elevated for up to 10 days
- because it stays elevated longer than CK-MB, it is a valuable marker when attempting to diagnosis injury in the recent past
- normal: less than 0.4 ng/mL
Myoglobin
- protein released and elevated in muscle damage but is not specific for cardiac tissue
- be used in conjunction with other values
- normal: 0-85 ng/mL
Brain Natriuretic Peptide (BNP)
released from overstretched ventricular tissue
- physiological responses to increased BNP include venous dilation which decreases preload, arterial dilation, which decreased afterload, and diuresis
- elevations are indicative of heart failure
- normal: less than 100 pg/mL
Nursing Implications for Laboratory Tests
- obtaining CK, CK-MB, and troponin is primarily associated with the timing of the blood draws
- when a patient is evaluated for acute injury, laboratory tests are obtained at baseline and then at regular intervals (typically 3 to 4 hours) for approximately 12 hours
