Weekend 2 lecture 4 Flashcards
Clinical Labs
- Serum enzymes
- Blood Lipids
- Complete Blood Count
- Coagulation Profiles
- Electrolyte levels
- BUN/Creatinine levels
- Blood glucose
Serum Enzymes
Serum Enzymes
•Troponin
Troponin whatbisbit a good indicator of?
Troponin
•Highly specific for MI
•Can be detected in the blood within 3 hours of MI associated chest pain
•Two isoenzymes: Troponin T & Troponin I
•Peaks at about 24 hours
Creatine Kinase-Myocardial Bands what time does it peak and what time does it normalize
Whatbpercent is usually a good indicator of MI what level
- It is common to calculate the ratio of CK-MB/Total CK. It is generally >2.5% if an MI has occurred
- Serum CK starts to rise at 4-8 hours following an MI and peaks at about 24 hours
- CK-MB normalizes by 48-72 hours
Isoforms of CK-MB
•CK-MB1 & CK-MB2 can also be used as markers
–CK-MB2 is released from infarcted myocardial tissues and is enzymatically converted in the circulation to CK-MB1
–This occurs within just a few hours, an elevated ratio of CK-MB2/CK-MB1 can be a very sensitive marker for MI
Lactate Dehydrogenase what time would you look at this compared to the ck levels
- Serum levels of LDH peak at about 3-5days
- Important marker for those persons who present to hospital/MD with several days of symptoms. If MI occurred 3 days ago the CK-MB would have normalized; therefore, LDH would be the marker you need to examine
Blood Lipids
•AHA cholesterol recommendations
–Total Cholesterol < 200mg/dl
–LDL < 130 mg/dl if no known heart disease
–LDL < 100 mg/dl if there is known heart disease
–HDL > 35 mg/dl
Ratio of Total Cholesterol/HDL
Men 3.43 4.9 what’s the rest
Women is 3.27
4.44 what’s the rest can remember just general like 3-11 might be eaiser
•Men –3.43 = ½ average risk for CAD –4.97 = Average risk –9.55 = 2x average risk for CAD –23.39 = 3x average risk for CAD •Women –3.27 = ½ average risk for CAD –4.44 = Average risk for CAD –7.05 = 2x average risk for CAD –11.04 = 3x average risk for CAD
Elevated triglyceride levels
What’s a dangerous level to be above
- 150mg/dl is defined as elevated triglyceride levels
- Associated with increased CHO ingestion
- May be a precursor to DM
Complete Blood Count
What stuff do they look at and what levels of Hgb good for men and women
What about hematocrit ?
What about wBC
Platelets
•Hemoglobin –Men: 13-16g/dl –Women: 12-14g/dl •Hematocrit –Men: 40-54% –Women: 37-47% •White Blood Cells •RBCs •Platelets
•WBC: 5000-10,000 •Platelets: 1.5-4.5 x 100,000 •RBCs: –Men: 4.8-6.0 x 1O6 –Women: 4.1-5.1 x 106
Please note that all reference ranges given may differ slightly from institution to institution
Coagulation Profiles
What’s reference range think pro
When do you look for prothrombin if they are on what meds?
When do you look for partial thromboplastin
If they are on what meds?
•PT (Prothrombin time)
–Reference range: 11.8-15.0 sec
–Look at this number if patient is being anticoagulated on coumadin or warfarin
–1.5-2x reference range is generally therapeutic for DVT/PE
•PTT (Partial thromboplastin time)
–Reference range: 21.7-34.0 sec
–Look at this number if patient is being anticoagulated on heparin. Generally you would like to see the number 1.5-2x the reference range to see that the patient is therapeutically anticoagulated
•International Normalized Ratio (INR)
What is this the purpose of this
•International Normalized Ratio (INR)
–Utilized so that anticoagulation levels can be compared across institutions. Uses a standardized solution, and thereby gives you the normality of the solution measured
•Eg: INR of 1 = a 1 normal solution
Electrolyte Levels what two are the high ones
- Sodium: 135-145
- Potassium: 3.5-5.0
- Chloride: 96-108
- Magnesium: 1.5-2.5
- Phosphorus: 2.4-4.7
- Calcium: 8.5-11
BUN/Creatinine what is this used to measure
whats the normal range for creainine
whats the range for blood urea
Measure of Kidney function. Elevated levels may also indicate worsening heart failure Blood urea nitrogen (BUN) Normal range: 10-30 Creatinine Women: .6-1.4 Men: .6-1.6 Ratio of BUN/Cr >15.5 is considered abnormal
Blood Glucose
what happens if the person is above 300
what is the normal range
what happens if they are above 400
Normal reference range
60-120
Blood glucose level > 300 should contraindicate exercise
Blood glucose level > 400 the patient is at risk for ketoacidosis
Cardiac Radiography (CXR) what is the x - ray inversely proptional to ?
Recall that penetration of x-rays through the body is inversely proportional to the tissue density
For a boundary to show between two tissues they must differ in density
Views
PA
Laterals
P-A xray view which view gives you better angulation of the clavicles P-A or A-P ???
Xrays are transmitted from behind the patient to a film placed against the chest on the anterior side
PA view there is a greater angulation of the clavicles
AP less of an angulation of the clavicles
Cardiac Silhouette How much of the chest space should the heart occupy??? How about a kid and when do you get misreads cause of what conditions???
The heart shadow should occupy 50% or less of the maximal width of the thorax as measured between inner margins of the ribs
In children normal cardiac shadow may occupy 60% of the maximal width of the thorax
Situations in which the cardiac shadow inaccurately reflects heart size: elevated diaphragm, narrow PA diameter of chest
Echocardiography what is this
Use of ultrasonic waves generated by a piezoelectric transducer which travel through the body tissues and are reflected and displayed through the sonography equipment
Non invasive procedure
Three Types of Echocardiographic Studies
M mode
One narrow ultrasonic beam
2-D mode
Multiple ultrasonic beams through a wide arc
Doppler ultrasonography
Evaluates blood flow direction, turbulence, and velocity, and allows for estimates of pressure gradients
Three Types of Echocardiographic Studies
M mode
One narrow ultrasonic beam
2-D mode
Multiple ultrasonic beams through a wide arc
Doppler ultrasonography
Evaluates blood flow direction, turbulence, and velocity, and allows for estimates of pressure gradients
TTE M Mode this is a type of “M mode” what is it used for????
Used for measurement of wall thickness & chamber diameters
TTE M Mode this is a type of “M mode” what is it used for????
Used for measurement of wall thickness & chamber diameters
TEE 2-D Mode this the “2-D mode” what is its purpose
Delineates part of a given cardiac structure, optimal evaluation of the entire heart is performed by combining multiple views. Views Parasternal long axis Parasternal short axis Apical views: 4chamber & 2 chamber
TEE 2-D Mode this the “2-D mode” what is its purpose
Delineates part of a given cardiac structure, optimal evaluation of the entire heart is performed by combining multiple views. Views Parasternal long axis Parasternal short axis Apical views: 4chamber & 2 chamber
TEE Doppler mode what is the “doppler mode” good for???
Color flow mapping converts the doppler signal to a scale of colors that represent direction, velocity, and turbulence
The colors are superimposed on the 2-D echo images
TEE Doppler mode what is the “doppler mode” good for???
Color flow mapping converts the doppler signal to a scale of colors that represent direction, velocity, and turbulence
The colors are superimposed on the 2-D echo images
What is the pressure of the following
RA,RV, PA, PV, LA, LV, Aorta
Pressure measurements RA pressure: 0-8 RV pressure: 15-30/0-8 PA pressure: 15-30/4-12 Lungs: PCW 1-10 LA pressure: 1-10 LV pressure: 100-140/3-12 Aorta pressure: 100-140/60-90
Measurement of Blood Flow (Fick equation)
Fick method is based on the fact that oxygen consumption is equal to the arterial-venous oxygen difference multiplied by the flow. In other words:
VO2 = a-vO2 diff x CO, thus Cardiac output can be determined by:
VO2/a-vO2diff = CO
Example of Equation:
Arterial blood contains 240ml O2/L
Venous blood contains 180ml O2/L
Measured oxygen consumption =260ml/min
CO = 260ml O2/min / 240 –180 ml O2/L
The CO = 4.33 L/min
Pulmonary Vascular Resistance equation think Left artrium and mean pulmonary artery pressure
CO = caridac output
PVR = (MPAP –LAP/CO) x 80 MPAP = mean pulmonary artery pressure LAP = mean left atrial pressure CO = cardiac output
How to determine systemic vascular resistance
SVR = (MAP – RAP/ CO) x 80
SVR = systemic vascular resistance MAP = mean arterial pressure RAP = mean right atrial pressure CO = cardiac output
Contrast Angiography whats this used for????
Uses radiopaque contrast material to visualize regions of the cardiovascular system.
Left ventriculograms
Coronary artery angiograms
Nuclear imaging this is the one with a tracer and a camera on it where contrast is more used with a dye to see the organs with an xray or MRI
Heart Function can be evaluated using injected radioactive tracers and gamma camera detectors
Used to assess
Myocardial perfusion
Image blood passing through the heart and great vessels
Localize and quantify myocardial ischemia
Assess myocardial metabolism
Radioisotopes used:
Thallium-201
Sestamibi
Blood Pool Imaging
Used to analyze right and left ventricular contractile function
Provides information on ejection fraction
Exercise Tolerance Testing what types are there???
What is this used
Many protocols for exercise progression
Bruce, modified Bruce, McNaughton, Story
Measure HR, BP, EKG tracings are continuous, and symptoms
May choose from multiple exercise modalities
May be pharmacologically induced
May be used in conjunction with echo or nuclear imaging
Computed Tomography
Uses x-rays to produce a planar image of the heart.
Particularly useful for assessing pericardial disease and aortic disease
May use serial images for management of aortic dissection and aortic aneurysm
MRI what is this good for???
useful when soft tissues need examining
Holter Monitoring what is this and what is it used for???
A 24 hour electrocardiogram monitoring of the patient.
Used when patient is experiencing symptoms which could potentially be caused by arrythmias
Exercise Tolerance Testing what types are there???
Many protocols for exercise progression
Bruce, modified Bruce, McNaughton, Story
Measure HR, BP, EKG tracings are continuous, and symptoms
May choose from multiple exercise modalities
May be pharmacologically induced
May be used in conjunction with echo or nuclear imaging
Blood Coagulation Tests
Prothrombin Time (PT)
International Normalized Ratio (INR)
Activated Partial Thromoplastin Time (APTT, PTT)
Activated Partial Thromboplastin Time (APPT, PTT) what is this about???
Used to screen for bleeding disorders ad measure effectiveness of Heparin therapy
Reference range: 21.7-34.0 sec
Therapeutic Range: 1.5-2x the reference range
APTT > 100 seconds corresponds with spontaneous bleeding. MD should be notified prior to therapy
What can high and low levels of Potassium and Sodium cause????
Sodium (Na+)
Low levels: Brain cell swelling
High levels: Increased risk for intracranial hemorrhage
Both high and low levels can cause a decrease in mental status
Potassium (K+)
Levels 5.0 are contraindications for exercise due to risk for life threatening cardiac dysrhythmias
What can high leveles of CO2, BUN, and Creatinine be an indication of???
Carbon Dioxide (CO2)
Low levels may alter mental status
Blood Urea Nitrogen (BUN)
Patients with renal failure (high BUN) may be anemic limiting exercise tolerance
Creatinine (Cr)
Patients with renal failure (high Cr) may be anemic limiting exercise tolerance
