Flashcards in Labs & Markers Deck (45)
Which lab tests should be performed on a patient to rule out secondary causes of dyslipidemia?
fasting blood glucose (DM), TSH (hypothyroidism), serum creatinine (renal function), UA for proteinuria (kidneys), alkaline phosphatase (liver)
Patients with clinical and angiographic evidence of coronary artery disease tend to have higher plasma levels of ...?
It is indicated to check homocysteine levels in which kind of patients?
high-risk patients with family hx of premature atherosclerosis or arterial occlusive disease
High levels of high-sensitivy C reactive protein have been show to show what?
strong independent predictor of cardiovascular and peripheral vascular disease risk and of recurrent cardiac events in patients with history of CAD or Acute coronary syndrome (ACS)
What are the hsCRP values that we should know?
>3mg/L → marker of high risk for death and MI
1-3 mg/L → intermediate risk
<1.0 mg/L → low risk
What components are included in a basic metabolic panel (BMP)?
Sodium, Potassium, Calcium, Chloride, Carbon Dioxide, Glucose, BUN, Creatinine
A complete metabolic panel has all components of a BMP and what else?
Alkaline Phosphatase, Total Bilirubin, AST/ALT, Total Protein, Albumin
If looking to evaluate liver and kidney function, which metabolic panel would be best?
If albumin levels are low, what other lab level will also be low?
calcium, half of calcium is bound to Albumin - need to calculate corrected calcium level
What are indications for ordering a metabolic panel?
aid in determining diagnosis, follow course of condition or treatment plan, monitor electrolytes, screen for occult disease
In what heart condition would you see decreased Na levels in a metabolic panel?
What electrolyte level is critical to monitor if a patient is on diuretic and/or other heart meds?
What can high K levels cause?
Which particular lab value serves as an index of both kidney and liver function?
What is better than BUN in indicating renal disease?
How do albumin and AST/ALT evaluate the liver?
Albumin tests liver function, where as AST/ALT tell you the integrity of the hepatocytes themselves (inflammation, breakdown). Both will tell you if you have liver disease, and how bad it is.
True/False it is uncommon to have a isolated abnormality on a metabolic panel?
True. You are usually confronted with a group of abnormal values. Exception: glucose
What is considered the old gold standard for myocardial injury?
creatine kinase (CK) has excellent sensitivity but poor specificity
CK levels will rise sharply after the onset of chest pain associated with an acute MI. But, other causes for increased CK include:
any musculoskeletal injury, IM injection, certain medications
What is the isoenzyme of CK that is most specific for myocardial tissues?
What is the biochemical marker of choice in the evaluation of patients with ACS?
cardiac-specific Troponins! (more specific than CK-MB)
Troponins are most beneficial in identifying AMI how many hours or more after symptoms onset?
Typically 6 (3-12 hr range), and will persist for 7-10 days
If a patient's troponins are normal at presentation, but the clinical index of suspicion is very high, when should the troponin levels be assessed in again?
In 6-12 hours
Which cardiac marker is preferred for early detection of an AMI?
How soon are elevated myoglobin levels detected and when do they return to normal?
Show 1-4 hours after onset of symptoms and peak 6-7 hours after. Will return to normal 24 hours post-MI
If you suspect a patient has Venous thromboembolism (VTE) which lab test should you order?
d-Dimer (used to diagnose thrombotic disorders)
Is d-Dimer specific for VTE?
No. A negative result can help rule out VTE/PE/DVT/DIC. But it is not specific enough to diagnosis VTE.
What other things can cause a positive d-Dimer test besides VTE?
malignancy, DIC, infection, inflammation, pregnancy
True/False. If myoglobin in normal in the first 6 hours, an MI is very unlikely.