Diagnostic tests Flashcards
First Pass Effect
Liver breaks down medication with enzymes based on drugs bioavailability
Aspartate Aminotransferase (AST)
NR: 10-40 units/L
Heart & Liver
High levels = heart/liver damage
Alanine Aminotransferase (ALT)
NR: 8-40 units/L
Specific to liver
If found in bloodstream, liver is damaged
Blood Urea Nitrogen (BUN)
NR: 10-20 mg/dl
>50 = poor kidney function
Creatinine
NR: 0.5-1.2 mg/dl
Low = low protein intake, severe liver disease
High = impaired kidney fxn, CHF, dehydrated
Potassium
NR: 3.5-5.0 mEq/L
Low = N/V, loss of KCL, cramps, diuretics
High = renal failure, cardiac arrest, NSAIDS, use of KCL
Half Life of medications
How long it takes for half of the dose to be eliminated from bloodstream
Examples of medications with long half-life
Anti-psychotics; medications taken once or twice daily
“Longer 1/2 life = greater compliance”
Examples of medications with short half-life
IV meds, morphine; sleep meds, anesthesia
Factors affecting drug action
Developmental considerations, weight, gender, genetic and cultural factors, psychological factors, pathology, environment, timing of administration
What is Heparin? What do you monitor?
Blood thinner
monitor Partial thromboplastin time (PTT)
NR: 25-35s (time for clotting)
If receiving IV Heparin, how does PTT differ?
PTT increases to 46-70 (increases time to clot; thins blood)
If clot time is low/normal, INCREASE Heparin
Trying to PREVENT formation of clots
Protamine to thicken blood
If receiving SQ Heparin, what do you monitor?
Monitor platelet count
What is Lovenox? What do you monitor?
Blood thinner; monitor platelets (control bleeding)
NR: 150,000-450,000 per microliter
Hold, if platelets <200,000 per microliter
What are the normal ranges of platelets for men? Women?
Men: 237,000 per microliter
Women 266,000 per microliter
Thrombocytopenia
Excessive bleeding, bruising (blood too thin)
<150,000 per microliter
Thrombocytosis
> 450,000 per microliter; blood too thick
What is prothrombin (PT)?
Indicates therapeutic level of Coumadin
NR: 9.5-13.5 s
*if still low/normal, increase Coumadin
higher the dose = thinner the blood
What is Coumadin? How do you monitor?
Oral blood thinner; monitor International normalized ratio (INR)
What are therapeutic ranges of Coumadin?
Standard therapeutic range = 2.0-3.0
Sub-therapeutic range = 1.2-2.0 (blood too thick)
3.0-4.5 in pts with valve replacements
What is the NR when not on Coumadin?
0.8-1.2s
What increases INR? How does it affect blood?
Coumadin, alcohol and aspirin
It thins out the blood (bleeding risk, slower clotting time)
What decreases INR? How does it affect the blood?
Vitamin K veggies (avocado, kale, spinach), CoQ10, green tea
Blood becomes thick (stroke risk, faster clotting time)
What are the normal Hemoglobin (Hb) ranges for men? Women?
Men = 14-18 Women = 12-16
