Medical Lab Flashcards
What are the two types of pathology labs?
Clinical and Anatomic
Hematology, Chemistry, Immunohematology, and Microbiology are examples of what kind of lab?
Clinical Pathology
What are the three types of Anatomic Pathology labs?
Autopsy, Cytology, Histology
The Clinical Lab of Hematology looks at what?
Looks at cellular components of the blood
The Clinical Pathology lab of Chemistry looks at what?
Any chemical reaction or make up of blood. Electrolytes, liver functions, etc
The Clinical Pathology lab of Immunohematology is also called what?
Blood bank
The Clinical Pathology lab of Microbiology checks for what?
Bacteria
Anything used to test humans must be cleared by what two things?
CLIA and FDA
A hospital lab gets results in ___ hours?
Within 24
What is a Reference Laboratory and what is the wait time?
A warehouse lab where special tests are performed. Turn-around can be lengthy.
What is a STAT laboratory?
Tests that can be done in an urgent setting for very quick results
What is a Point of care Test (POCT)? What is “waived” about them?
Device used at patient that gives immediate result. EX glucometer, coumadin levels. “CLIA-waved”.
What type of testing is CLIA waved for?
Point of care Testing (POCT)
What is Quality Control?
Gives confidence that results are accurate and reliable
What are two types of controls in Quality Control?
Internal Control, External Control
What does Internal Control check?
Test is working as it should, enough sample added, sample is moving correctly, electronics of device are working
What does External Control check?
Entire testing process is performed correctly and control results are within expected range
What are three types of ranges?
Reference range, Desirable range, Therapeutic range
Define Reference Range
Ranges of values considered normal for that test. Made from healthy, unmedicated individuals in 95% of people.
What is a Desirable Range?
Establishes a range where people want to be in order to have a healthy outcome. EX: cholesterol below a certain number
Define Therapeutic Range
Range while treating someone, shows if PT is adaquetly medicated. ex INR while on coumadin
Define “Sensitivity”
If catching positives, including false positives. EX: HIV test is very sensitive and will catch everyone with HIV but also people who don’t have HIV (False Positive)
Define “Specificity”
If positive from sensitivity then certain that is it. Can exclude false positives. EX: Specific HIV testing rules out those who falsely tested positive via sensitivity
Define “Prevalence”
A lot of people having something means more people will test positive
What are the two types of Predictive Values?
Positive Predictive Value and Negative Predictive Value
Define Positive Predictive Value
Likelihood that positive test identifies someone with the disease
Define Negative Predictive Value
Likelihood that negative test result identifies someone without disease
Threshold is when what two things are minimized?
Minimize false negatives and false positives
Threshold is a compromise between what two things?
Sensitivity and Specificity
Define Accuracy
If you hit the target, aka “is it correct”?
Define Precision
How reproducable a test result is
A clinical lab is one of the few ways to get _____ data
Objective
What are the 5 indications to order a lab test?
Screening, establish a diagnosis, monitor disease, monitor therapy/management, testing related to specific events
What is screening?
An indication to order a lab test. When check population for disease ex >50y/o for colon cancer. No symptoms required. ex newborn screenings.
Are symptoms requires for ordering a lab test based on “screening”?
No symptoms requires. Are routine tests like cholesterol or new baby testing
What is the reason behind the lab test reason of “Establish Diagnosis”?
When you’re not completely sure what the diagnosis is and need test to help confirm suspicion
What is the reason behind using “Monitor Disease” to order a lab test?
To see how the disease is progressing over time. EX HbA1C which gives a 3 month glucose evaluation
What is the reason behind using “Monitor Therapy” to order a lab test?
EX: INR. Need to know if the treatment is having the desired result in order to avoid issues
What is the reason behind using “testing related to specific event” to order a lab test?
When there are specific signs or symptoms. ex car accident, sexual assault
What/where are the three types of blood?
Venous, arterial, capillary
What is a very common type of patient preparation before a lab test?
Fasting
What are the two most common types of urine tests?
Clean Catch, Random Urine
What is a “clean catch”?
Urine test that gets rid of external contaminants better than peeing and catching midstream
What is a Random Urine test?
Collecting urine sample without cleaning ahead of time
What will Formalin do to a culture?
Kills the culture and everything else
What does a tourniquet allow when doing a venipuncture?
Prevents venous return allowing swelling of vein and easier collection of veinous blood
What is special about vacutainer holder?
Has suction, negative pressure environment to draw out blood
Should you load the vacutainer onto the needle before insertion into a vein?
NO!
What are the three most common veins to draw blood from?
Cephalic Vein, Median Cubital Vein, Basilic Vein
What does the gauge number represent with regards to a needle diameter?
The small the number the larger the diameter.
What are the most common gauge sizes for veinpuncture?
21, 22, 23
What can small needles do to blood during a venipuncture?
Lyse the RBCs making the test no good
Which way should the lumen be pointed during a venipuncture?
UP!
What is in a “light blue top” and what test is it for?
Citrate for coag studies.
What is in a red top and what is it for?
No additives. The blood clots and is serum. For chemistry studies, some blood bank, drug monitoring
What is in and what does a red/black stripe top do?
SST. Stimulates blood to clot, serum/cell separator.
What is in and what does a Green Top do?
Heparin for anticoag. Checks coagulation and sometimes for cardiac enzymes.
What is in and what does a Lavender/Purple top do?
EDTA anticoagulant. For CBC, hematology studies.
Why do some samples need light protection?
UV can break down some things like bilirubin
What should be on a label for a specimen?
PT name, dob, initials of specimen takee, date time taken, what specimen is, and where taken on body
How can hemolysis screw up a sample?
Red blood cells open up then screws up serum levels as the cells spill their intracellular contents into the serum and screw up test results
What does centrifuging to do a blood sample?
Separates serum from cellular components
Define lipemic
Very high triglyceride levels
What does Serum lack that Plasma has?
Serum lacks clotting factors
Plasma has ____ while serum doesn’t.
Plasma has clotting factors
In centrifuge where do the non-cellular components end up?
Rise to the top
Which tops for serum?
SST and Red Top
Which tops for Plasma?
Blue, purple, or green.
What does Serum look like vs Plasma?
Serum is clear, Plasma is slightly cloudy
If test results don’t make sense what should you do?
Redraw and retest
At what phase of blood testing do most errors occur?
Most errors in pre-analytical. During PT preparation until specimen gets to lab.
Hemolysis can mess up what type of electrolyte count?
Potassium spilling from inside RBC due to hemolysis
Icteric is another name for what?
Jaundice
Jaundice aka
Icteric
Describe jaundice/icteric specimines
jaundice. icteric=high bilirubin and brownish color change. tests done through spectometry and if specimen is discolored then can’t get accurate result
What is the first steps before taking a blood sample?
Identifying PT with two forms of ID (name and birthdate) and checking for any pre-draw instructions (fasting)
What time do you remove the tourniquet?
1 minute
Arteries are more ____ to the touch and have thicker or thinner feeling walls?
More elastic to the touch; thicker feeling walls
What is the motion for the alcohol prep pad? How do you dry it?
Fluid, circular motion from center to periphery. Let air dry to prevent contamination.
Where do you place your thumb when doing a venipuncture?
2 inches below the intended puncture side and pull skin taught to keep vein anchored in place
What is the angle when inserting a needle into a vein?
30 degrees
Once blood starts flowing into the vacutube what do you do with the tourniquet and PT’s hand?
Remove tourniquet and relax hand
How many times do you mix by inversion after drawing blood into tube?
Gently 8 times to ensure additives are mixed into the sample
Apply pressure at needle puncture site immediately after withdrawing needle enables what to happen and prevents what?
Prevents a hematoma, allows hemostasis
Serious complications most happen at which vein? How?
Basilic vein due to close proximity to nerves and brachial artery which can be niched
What gauge is a Butterfly Needle?
23-25 gauge
What can happen do the RBCs when using a Butterly Need or similar sized bore?
RBCs can lyse due to too small bore which screws up results
What is a hematoma?
Bleeding from vein into surrounding space under skin. Bruised in appearance and painful to touch.
When can a hematoma form?
When you don’t put immediate pressure on a venipuncture side
To prevent release of shut off valve on tube what do you do?
Keep a constant and slight forward pressure on end of tube
As soon as blood begins to flow into the tube what do you do?
Tell PT to relax hand and remove turniquet
What is the color order for filling tubes?
Light blue, red, gold, green, lavender, grey
Normal number of RBCs?
3.5-5.5 million
Normal number of WBCs?
4.5-11 thousand
Normal number of thrombocytes (platelets)?
150-400 thousand
Where is the problem in Pancytopenia?
Bone marrow problem
Define Pancytopenia
Decrease of all cell lines (RBCs, WBCs, platelets)
Define Anemia
Reduced number of RBCs
Define Polycythemia
Increased number of RBCs
Define Thrombocytopenia
Decreased platelets
Define Thrombocytosis
Increased platelets
Define Leukocytosis
Increased WBCs
Define Leukopenia
Decreased WBCs
Define Neutopenia
Decreased neutophils
What sort of precaution does neutropenia require?
Reversed precautions. Protecting PT against the world.
Define Leukemoid Reaction
Benign and temporary WBC increase (leukocytosis) in response to normal illness
Define Hematopoiesis
Production of blood cells
Define Erythropoiesis
production of RBCs
Define Thrombopoiesis
Production of platelets
Define Leukopoiesis
Production of WBCs
Define Lymphopoiesis
Production of lymphocytes
Define Medullary Myeloid Hematopoiesis
Production of myeloid blood cells in bone marrow
Define Extramedullary Hematopoiesis
Production of blood cells outside bone marrow (in liver or spleen). Usually indicates a malignancy.
What is the only blood cell that is not from the myeloid line?
Lymphocytes
What is “Peripheral Flow”
Blood flow outside of bone marrow and out in the system
Where do T-cells mature?
T cells mature in thymus.
Where to B-cells mature?
B cells mature in bone marrow.
Where do NK cells mature?
Bone marrow
B cells are involved in what type of immunity?
Humoral immunity involved in production of antibodies.
What are B cells involved in production of?
Antibodies
T cells are involved in what type of immunity?
T cells involved in cellular immunity.
What is the average life of a RBC?
120 days
What triggers Erythropoiesis?
Decreased oxygen levels
What is the most abundant blood cell in the body?
Erythrocyte
What is the shape of a RBC?
Biconcave disc
What does the shape of an RBC enable?
Biconcave disc increases surface area to enable oxygen carrying capacity.
What percent of RBCs are destroyed in a day?
1%
What are the two main components of an RBC?
4 Hemes and 4 Globins
Where is Iron (Fe) absorbed?
Absorbed in intestines
What does Bilirubin do?
Breaks down heme portion of RBC
What is the least abundant blood cell type?
Leukocytes
How many types of Leukocytes are there?
5
What is the purpose of Leukocytes?
Fight infection and remove debris
Which three WBCs are the “Granulocytes”? What do the granules do?
Neutrophils, Eosinophils, Basophils. Granules contain enzymes which helps break things down
An atypical lymphocyte usually means what type of infection?
Infectious mononucleosis EBV
What to Neurophils fight against?
Bacterial infection.
A “left shift” or an increase in “bands” is associated with what WBC?
Neurophils
What is the job of Monocytes?
Clean blood.
What do Eosinphils fight against?
Parasitic infections, allergic response
Which WBC has orange granules?
Eosinophils
What do Lymphocytes fight against?
Viral illness, mononucleosis, involved in immunity. Can live up to 20 years.
Basophils are often seen in with what?
Malignancy. Basos are bad.
What are the three types of Lymphocytes?
B, T, NK
Thrombocytes are made from…?
Megakaryocytes. “Pinched off pieces of cytoplasm.”
What is the purpose of Thrombocytes?
Coagulation
What does CBC stand for?
Complete Blood Count
What type of blood is drawn for a CBC?
Venous blood
What “top” tube is used for CBC? What does this tube contain?
Lavender. Contains EDTA to prevent coagulation.
How much more Hematocrit is there than Hemaglobin?
3x more Hematocrit
What is “Hct”
Hematocrit. AKA Packed Red Blood Cell volume
Define MCV and what it represents
Mean Corpuscular Volume. Represents size of cell.
Define MCH and what it represents
Mean Corpuscular Hemoglobin. Represents amount of hemoglobin per RBC.
Define MCHC and what is represents
Mean Corpuscular Hemoglobin Concentration. Mean content of total Hbg
Define MPV and what it represents
Mean Platelet Volume. Average volume (size) of platelets.
What is normal Hemoglobin (Hgb) value?
12-15 g/dL
What is normal Hematocrit (Hct) value?
36-45
What is normal WBC value?
5000-10,000
What is normal platelet value?
150,000-400,000
What are the values for mild neutropenia?
more than 1000 and less than 1500
What are the values for moderate neutropenia?
more than 500 and less than 1000
What are the values for severe neutropenia?
ANC less than 500
What is a CBC Peripheral Smear?
Looking at sample on a slide
MCV relates to what about the RBC?
MCV relates to size!! 80-100
MCH and MCHC relate to what?
MCH and MCHC relate to color (hemaglobin) “normochromic”
Define Normocytic
Normal RBC cell size, 6 to 9 micrometer µm
Define Anisocytosis
Variation in RBC cell size
Define Microcytic
Small RBC cell size, less than 5µm
Define Macrocytic
Larger RBC cell size larger than 10 µm
Define Normochromic
Normal hemoglobin color
Define Anisochromia
Variation in hemoglobin color
Define Hypochromic
Decrease in hemoglobin color
Define Hyperchromic
Increased hemoglobin color
Who are Target Cells found in?
Mainly in alcoholics
What does a Target Cell represent a change in?
Change in Hemoglobin
What are Schistocytes?
Fragments of RBCs
What can cause Schistocytes?
Artificial valve shearing RBCs
Does an RBC have a nucleus when in peripheral circulation?
No
When does an RBC have a nucleus?
Nucleus in RBC should only be in bone marrow. Loses nucleus before gets into peripheral circulation.
When would you order a CBC with manual diff?
Malaria. When you need to be very careful in counting.
Elevated Lymphocytes indicates what sort of infection?
Viral infection
Increased Eosinophils means what two possible issues?
Parasitic infection or Allergic reaction
What might be seen in PT who is dehydrated?
Decrease plasma, falsely elevated RBC and H&H.
After you treat a dehydrated PT with IV fluids what would their plasma, RBCs, and H&H look like?
Normalize. Drop in RBC back to normal and H&H back to normal.
Does does “H & H” stand for?
Hemoglobin and Hematocrit
Is a Bone Marrow sample necessary in most cases of anemia?
No
What is Flow Cytometry able to prevent in some cases?
Able to prevent some Bone Marrow biopsies
What is a major indication for Bone Marrow examination?
Pancytopenia; reduction in RBCs, WBCs, and Platelets
What are some absolute contraindications against Bone Marrow aspiration?
Hemphilia, Severe Disseminated Intravascular Coagulopathy, other severe bleeding disorders
At what platelet count must you be VERY careful when doing a bone marrow aspiration?
Anything 20,000 or less. They can bleed super easily.
When is Bone Marrow examination NOT contraindicated?
Thrombocytopenia (decrease in platelets/thrombocytes) in blood, therapeutic anticoagulation
What is the most common site for bone marrow aspiration?
Posterior Superior Iliac Crest
What is a bone marrow “Dry Tap”?
When no sample can be obtained by aspiration
What is a Buffy Coat?
buffy coat=white blood cells on the top of the test tube
What is found in a Reticulocyte that shouldn’t normally be found?
Nucleus still present. Still some leftover RNA in cell.
What is the normal Reticulocyte Index (RPI) range?
2.0-3.0
What is the Reticulocyte Index? What does it give a good measure of and what can it compensate for?
Can compensate for anemia. Gives a better measure of what’s happening in the bone marrow.
What does ESR stand for?
Erythrocyte Sedimentation Rate
What does ESR test for?
Hemetological test that measures inflammation but is nonspecific and can be lots of different things causing it (infectious, noninfectious, autoimmune….anything that causes inflammation). For monitoring conditions but not for diagnosis.
What is the limitation of ESR?
Only shows a non-specific measure of inflammation but not why or what. Used for monitoring conditions but not diagnosing them.
If someone has IBS and you want to measure their level of inflammation what test would you order?
ESR
What color top for ESR? How is the rate measured?
Purple Top or another special tube. Sits there for 1 hour and amount of RBCs that settle in 1 hour is the “rate”.
What is a Hemoglobin Electrophoresis test?
Electric current that has proteins travel and settle into bands. Can check globin chains. Good for sickle cell disease and similar. Very important study in hematology.
What is Flow Cytometry?
Laser-based technology that can physically sort particles based on their properties.
What does Flow Cytometry look at?
Looks at specific cell markers (biomarkers or “CD”) proteins on cell surface that are measured. Ex antibody on RBC cell surface can be found and correlated to different diseases based on antibodies present.
What are the cell called that Flow Cytometry looks at?
Biomarkers or “CD”
What are the “shifts” in anemia?
Right shift=oxygen gets off sooner; Left shift=oxygen stays longer.
Should get off at capillary
What does a Right Shift mean in anemia?
Oxygen gets off sooner. Lower affinity to oxygen.
What does a Left Shift mean in anemia?
Oxygen stays longer. Higher affinity to oxygen.
What does DPG control?
DPG controls oxygen movement from RBC to tissue. Changes oxygen affinity.
What three lettered chemical changes oxygen affinity?
DPG controls oxygen movement from RBC to tissue. Changes oxygen affinity.
What kind of heart problem can anemia lead to?
Demand Ischemia, damage to heart d/t not enough oxygen delivered to heart.
What are some common symptoms of anemia?
Fatigue, dizziness, weakness, syncope, pallor, jaundice, dyspnea, palpitations, chest pain/MI, no symptoms
What are the two causes of anemia?
Increased RBC destruction/loss or decreased production of RBCs
What are some common signs of anemia?
Koilonychia (“spooning” of nails), “bossy” prominent forehead d/t bone marrow in frontal bone working overtime, jaundice (increase in bilirubin and yellowish color due to increased breakdown)
What does jaundice represent in anemia?
jaundice=increase in bilirubin and yellowish color due to increased breakdown of RBCs
Jaundice is an increase in what?
Increase in bilirubin and yellowish color due to increased breakdown of RBCs.
What is the first test to run for diagnosing a CBC? What is the second test?
First test for anemia is CBC. Also run reticulocyte count to determine if bone marrow making enough cells.
What are the three “cytic” classifications for anemia?
Microcytic (MCV less than 80), Normocytic (MCV 80-100), Macrocytic (MCV more than 100)
What is the three lettered test on a CBC that measured anemia?
MCV
Amenia’s low value is….?
MCV less than 80
Amenia’s normal value is?
MCV 80-100
Amenia’s high value is?
MCV more than 100
What is a “true clot”?
Both platlets and fibrin. Both systems active.
What three things make up Hemostasis?
Vessel constriction, Platelets, Coagulation cascade
What are the three steps of coagulation?
step 1 plaetlet adhesion (reversible); step 2 platelet activation (reversible); step 3 platelet aggregation (not reversible)
Of the three steps of the coagulation cascade which are reversible and irreversible?
step 1 plaetlet adhesion (reversible); step 2 platelet activation (reversible); step 3 platelet aggregation (not reversible)
What do Platelet Function Studies check?
Platelet count, bleeding time, platelet aggregation, platelet antibody studies
What is a Platelet Aggregation study?
done in test tube with platelet rich blood sample (blue top), spin down, take off platelet rich plasma on top, add a platelet activator to cause to aggregate, and use spectometry to measure platelet function
What is the Bleeding Time study?
Lancet is done in two places and time how long until clot. 2 minutes is normal but can be very varibale. Not done often.
What is a Quantitative Platelet Disorder?
Disorder of numbers of platelets (thrombocytopenic).
What is a Qualitative Platelet Disorder?
Disorder of function of platelets. May have right or high number but not working correctly.
Coagulation medications work on what component of blood?
Platelets
Use anti-coagulants when worried about what?
Thrombosis
COX1 inhibitors work on platelet _____?
Platelet Activation
Example of COX1 inhibitor?
Aspirin
Aspirin has what effect on platelets?
Prevents platelet activation
What class is aspirin?
COX1 inhibitor
P2Y12 medications prevent Platelet _____
Platelet Activation
Example of P2Y12 platelet meds?
Plavix, Effient, Brilinta
What are the two classes of Platelet Activation inhibitors?
COX1 Inhibitors, P2Y12 Inhibitors
Glycoprotein IIb/IIIa Inhibitors prevent Platelet _____
Platelet Aggregation
PDE5 Inhibitors prevent Platelet _____
Platelet Aggregation
What are the two classes of Platelet Aggregation inhibitors?
Glycoprotein IIb/IIIa Inhibitors, PDE5 Inhibitors
Anti-coagulants inhibit what?
Inhibit clotting (platelets)
Which vitamin does Coumadin inhibit?
Vitamin K
How does Coumadin work?
Inhibits vitamin k dependent factors 2, 7, 9, 10.
What does Heparin work on?
Anti-thrombin 3a
What are two very common anti-coagulation meds?
Coumadin, Heparin
Which Factor does Coumadin drop the quickest?
Drops Factor 7 the quickest
If you need to drop Factor 7 very quickly what do you use?
Coumadin
What does the coagulation test “aPTT” stand for?
aPTT=Activated Partial Thromboplastin Time
The aPTT test is Instrinsic or Extrinsic?
Intrinsic
What does the aPTT blood test measure?
Measures the effect of Heparin on clotting. Heparin prolongs aPTT.
What does the coagulation test PT stand for?
Prothrombin
Does the PT test check the Instrinsic or Extrinsic Pathway?
Extrinsic Pathway 7
Which medication effects the PT test?
Coumadin
Which medication effects the aPTT test?
Measures the effect of Heparin on clotting. Heparin prolongs aPTT.
What does the TT test stand for?
Thrombin Time
What does the TT test check the conversion of?
Thrombin to Fibrinogen
What is Anti-Factor Xa Activity test used for?
Measures the degree of anticoagulation. Can measure for heparin. Being used in place of PTT.
What is Anti-Factor Xa Activity being in place of?
PTT
Define Thrombosis
Creation of clots
Define Thrombolysis
Breakdown of clots
Thrombosis is when a person is unable to do what to clots?
Unable to breakdown clots.
What is a “Mixing Study”?
Take plasma and mix with pooled plasma and if normalize then likely a factor deficiency. If still not normal then likely an inhibitor problem.
Can mix with specific factors to be specific about which is missing
What does a D-Dimer test look for?
Test of fibrin degredation products. Means there has been a clot and the body has broken it down (fibronolysis).
The D-Dimer looks for what products?
Fibrin degredation products. means there has been a clot and the body has broken it down (fibronolysis).
If a D-Dimer test is positive what does it mean?
There has been a clot and the body has broken it down (fibronolysis).
What is the sensitivity and specificity of the D-Dimer test?
SENSITIVE BUT NOT SPECIFIC!
Is D-Dimer used to rule in or out clots?
Used to rule OUT and not in. If D-Dimer is normal then there hasn’t been a clot but if D-Dimer is positive it means there was a clot.
What is one place a D-Dimer test is useless?
Surgery. D-Dimer is useless as they are forming lots of clots from having been cut open.
What two things does D-Dimer indicate?
Indicates there was a thrombosis (clot) along with thrombolysis (clot breakdown). D-Dimer tests for clot breakdown products.
Anti-coagulants inhibit what?
Inhibit clotting (platelets)
Which vitamin does Coumadin inhibit?
Vitamin K
How does Coumadin work?
Inhibits vitamin k dependent factors 2, 7, 9, 10.
What does Heparin work on?
Anti-thrombin 3a
What are two very common anti-coagulation meds?
Coumadin, Heparin
Which Factor does Coumadin drop the quickest?
Drops Factor 7 the quickest
If you need to drop Factor 7 very quickly what do you use?
Coumadin
What does the coagulation test “aPTT” stand for?
aPTT=Activated Partial Thromboplastin Time
The aPTT test is Instrinsic or Extrinsic?
Intrinsic
What does the aPTT blood test measure?
Measures the effect of Heparin on clotting. Heparin prolongs aPTT.
What does the coagulation test PT stand for?
Prothrombin
Does the PT test check the Instrinsic or Extrinsic Pathway?
Extrinsic Pathway 7
Which medication effects the PT test?
Coumadin
Which medication effects the aPTT test?
Measures the effect of Heparin on clotting. Heparin prolongs aPTT.
What does the TT test stand for?
Thrombin Time
What does the TT test check the conversion of?
Thrombin to Fibrinogen
What is Anti-Factor Xa Activity test used for?
Measures the degree of anticoagulation. Can measure for heparin. Being used in place of PTT.
What is Anti-Factor Xa Activity being in place of?
PTT
Define Thrombosis
Creation of clots
Define Thrombolysis
Breakdown of clots
Thrombosis is when a person is unable to do what to clots?
Unable to breakdown clots.
What is a “Mixing Study”?
Take plasma and mix with pooled plasma and if normalize then likely a factor deficiency. If still not normal then likely an inhibitor problem.
Can mix with specific factors to be specific about which is missing
What does a D-Dimer test look for?
Test of fibrin degredation products. Means there has been a clot and the body has broken it down (fibronolysis).
The D-Dimer looks for what products?
Fibrin degredation products. means there has been a clot and the body has broken it down (fibronolysis).
If a D-Dimer test is positive what does it mean?
There has been a clot and the body has broken it down (fibronolysis).
What is the sensitivity and specificity of the D-Dimer test?
SENSITIVE BUT NOT SPECIFIC!
Is D-Dimer used to rule in or out clots?
Used to rule OUT and not in. If D-Dimer is normal then there hasn’t been a clot but if D-Dimer is positive it means there was a clot.
What is one place a D-Dimer test is useless?
Surgery. D-Dimer is useless as they are forming lots of clots from having been cut open.
What two things does D-Dimer indicate?
Indicates there was a thrombosis (clot) along with thrombolysis (clot breakdown). D-Dimer tests for clot breakdown products.
