Variation in Lab tetsing Flashcards
Physiological state changes may result in…
abnormal lab tests
Meals stimulate the production of…
Gastric acid
What happens to HCl, pH, and plasma chloride concentration when you eat?
- Decrease HCl
- Increases pH
- Decrease plasma Cl
What does glucose absorption do?
- Stimluates the release of insulin
- Insulin causes the uptake of K into cells
- Decreasing plasma K levels (hypokalemia)
Non-fasting samples may result in _____ test results?
Abnormal
When are the most reproducible test results obtained?
When the patient is fasting for 8-12 hours
What effects does stress have on test results?
Stress increases your BV, and then increased your BP
-Increased BV causes a dilution of plasma proteins
As a clinician, what should you do if your patient is under stress?
Don’t order elective testing if your patient is under stress
Describe the effects of exercising
Patients who exercise regularly have increased levels of plasma enzymes
What are examples of plasma enzymes?
- Creatinine kinase
- Asparate aminotransferase
- Lactate dehydrogenase
Where are plasma enzymes found?
The liver
What are high levels of plasma enzymes often confused with?
Liver disease
Describe cyclic variation
Reproducible patterns of alteration in physiologic state that occur at specific days, months, or year
What is an example of cyclic variation?
Pituitary hormones
What type of variation do pituitary hormones demonstrate?
Ultradian variation
Define Ultradian variation
Variation occurring in less than a day
How are pituitary hormones released?
Episodic bursts (results in periods of peaks and valleys)
Example of cyclic variation
Cholesterol is 25% higher during the 2nd half of the menstrual cycle
What effect do diaretics have?
They pull of fluid, sodium, and potassium
What happens when a patient is in an upright position?
- Water and electrolytes are lost from the vascular space
- Proteins and protein bound substances become very concentrated
What happens when you go from a sitting to a supine position?
Water and electrolytes move back into the vascular space
-Reduces the concentration of proteins by 10-15%
What happens if you have high venous pressure?
- The return of water and electrolytes to venous blood is impaired
- This increases the concentration of proteins and protein bound substances
How much does concentration increase after 3-5 minutes of tourniquet time?
5%
How much does concentration increase after 10-15 minutes of tourniquet time?
15%
As venous pressure remains high, circulation of fresh blood ______
Decreases
What happens when the circulation of fresh blood decreases?
The cells continue metabolizing and the glucose decreases and lactate increases
What does increased lactate result in?
Acidosis
What does acidosis do to potassium?
Leads to leakage of K from cells, and elevates serum K levels
What happens when you clench your fists?
Accelerates the rate that metabolic changes occur
-Increases serum K by 1-1.5 mmol/L in 1 minute
If a patient has an IV, where do you take the blood sample from?
-Below where the IV is placed
What color is the tube for… CBC?
Lavender
What color is the tube for… metabolic panels
Red
What color is the tube for… lipid profiles
red
What color is the tube for…Thyroid function tests
red
What color is the tube for… coagulation studies
blue
