Lab Tests Flashcards
What is the difference between a Comprehensive Medical Panel and a Basic Metabolic Panel?
The comprehensive medical panel has all the tests as the basic metabolic panel plus Albumin, Total Protein, and the liver tests of liver function
What eight values does a Basic Metabolic Panel test?
Glucose, Sodium, Potassium, Chloride, Carbon Dioxide, Calcium, Creatinine, and BUN
What are the tests for liver function?
ALP, ALT, AST, and Bilirubin
Volume of packed RBCs in 100 mL of blood
Hematocrit
In what diseases is hematocrit lowered?
Acute blood loss, anemia, cancers, cirrhosis, malnutrition, vitamin B and C deficiencies, leukemia, and renal failure
In what conditions is hematocrit increased?
Dehydration, hypovolemia, and polycythemia vera
Which drug can cause a low hematocrit?
Penicillin
What is the critical value of hematocrit?
<15%
What can a critically low hematocrit lead to?
Heart Failure
A protein substance in RBCs that is composed of an iron and globin?
Hemoglobin
What conditions can lead to decreased hemoglobin levels?
Anemia, cancers, kidney disease, and excess IV fluid
What conditions cause increased hemoglobin levels?
Dehydration, polycythemia, high altitudes, and COPD
Low hemoglobin levels put the patient at risk for what complications?
Angina, heart attack, and heart failure
Too high hemoglobin levels can lead to what complications?
Stroke and organ infaction
What are the critical values of hemoglobin?
20
What are signs and symptoms of anemia?
Fatigue, pallor, and tachycardia
What is the appropriate BUN range?
10-20 mg/dL
What is a BUN level a measure of?
Liver function, and indirectly, kidney function
What conditions result in abnormally low BUN levels?
Liver failure, over hydration, negative nitrogen balance, nephrotic syndrome and a low protein diet
What causes a negative nitrogen balance?
Malnutrition and malabsorption
What is the medical term for increased BUN levels?
Azotemia
What are the prerenal causes of azotemia?
Reduced blood volume, reduced renal blood flow, GI bleeding, excessive protein feeding, excess protein catabolism, and sepsis
What conditions might cause reduced blood flow to the kidneys?
CHF and MI
What are the renal causes of azotemia?
Renal disease, renal failure, and nephrotoxic drugs
What are the postrenal causes of azotemia?
Urethral obstruction and bladder obstruction
What is creatinine a byproduct of?
Muscle catabolism
What are the normal ranges of Creatinine in males and females?
0.6-1.2 in males, 0.5-1.1 in females
What do high creatinine levels indicate?
Acute and chronic renal failure, reduced renal blood flow, cancers, lupus, and rhabdomyolysis
What do decreased creatinine levels indicate?
Muscle atrophy and reduced muscle mass
What can cause a transient elevation in creatinine levels?
Diets high in meat
What is bilirubin made from?
The heme of old or damaged RBCs
At what serum level of bililrubin would the patient be jaundice?
2.5 mg/dL
What would cause a rise in indirect bilirubin levels?
Hemolysis and hepatocellular injury
What would cause a rise in direct bilirubin levels?
Obstruction and cancers
What would cause a rise in total bilirubin levels?
Biliary obstruction
What is the critical level of bilirubin in adults?
> 12 mg/dL
What is the critical level of bilirubin in newborns?
> 15 mg/dL
Newborn jaundice is generally caused by what type of bilirubin?
Indirect
How can the nurse prevent increased bilirubin levels?
Avoid hemolysis of blood products and lab specimen and protect samples from bright lights
What does an alkaline phosphate test monitor?
Diseases of the liver and bone
What would cause an increase in alkaline phosphates?
Biliary obstruction and cholestatic hepatitis
What does a serum aspartate aminotransferase test (AST) monitor?
Enzymes found in the heart and liver muscle
What does a serum alanine aminotransferase test (ALT) monitor?
Enzymes found in the liver
Of the liver enzyme function tests, which is the most specific measurement of the liver enzymes for hepatocellular disease?
Alanine Aminotransferase
When a hepatocellular injury occurs, what happens to the levels of Aspartate Aminotransferase and Alaninie Aminotransferase?
They rise
What tests are done to measure coagulation time?
PT, aPTT, PTT, INR
What is the normal Prothrombin Time?
11-12.5 seconds
What conditions does a decrease in prothrombin time indicate?
Thrombophlebitis and pulmonary embolus
What does an increased prothrombin time indicate?
Anticoagulation therapy, liver disease, coagulation defect, and malasorption
Which anticoagulation drugs cause a change in Prothrombin time?
Aspirin and Coumadin
What is the normal INR range?
0.7-1.8
What is a therapeutic INR range?
2.0-3.5
Why is INR and PT used?
To provide a better interpretation of the results
What can increase coagulation times and counteract coagulation therapy?
Vitamin K
What should the nurse assess on a patient with prolonged prothrombin times?
Bleeding tendencies like hematuria, bruising, petechiae, and back pain
What is the normal aPTT range?
21-40 seconds
What is the critical value of an aPTT?
70 seconds
When is an aPTT used?
When the patient is on heparin
What is the normal PTT range?
60-70 seconds
What is a critical PTT value?
100 seconds
What does PTT evaluate?
Intrinsic system of clotting
What does a PT evaluate?
Extrinsic clotting system
What would cause a decrease in an aPTT/PTT?
Ovarian, pancreatic, and colon cancer
What would cause an increase in an aPTT/PTT?
Cirrhosis, vitamin K deficiency, anticoagulants
When should the aPTT be completed?
30-60 minutes before the next scheduled heparin dose
How would a nurse assess a patient on anticoagulants for bleeding?
Look at the urine, skin, gums, and stool
How can heparin be reversed?
Protamine sulfate
What is the total protein value a combination of?
Prealbumin, albumin, and globulins
Protein test indicating nutritional status and liver function
Preablumin
Why is prealbumin a good indicator of nutritional status?
Because it has a short half-life
In which patients is a prealbumin level especially important in?
Those receiving TPN
Proteins formed in the liver that maintain colloidal osmotic pressure
Albumin
What does albumin transport?
Drugs, hormones, and enzymes
Building blocks of antibodies, glycoproteins, lipid proteins, and clotting factors
Globulins
What are the most common critical values called in to the nurse?
Potassium, Glucose, WBCs, Hemoglobin, Hematocrit, Platelets, Calcium, and Troponin
What is a normal fasting glucose range?
70-100 mg/dL
What is a normal WBC count?
5000-10000/mcL
What is a normal platelet count?
150,000-400,000/mcL
What is the normal range of Hemoglobin in males and females?
14-18 g/dL in males and 12-16 g/dL in females
What is the normal Hematocrit range in males and females?
42%-52% in males and 37%-47% in females
What does a hematocrit level of <24% indicate?
The need for a transfusion
