Card Set Information
Platelet Retic ACT Fibrinogen
What can abnormal results for fibrinogen test indicate?
Low- clotting disorders
How is the ACT test done?
Collect 2mL of blood into the vacutanier tube containing diatomaceous earth
Start timer, mix gently
Place in 37 degrees incubator or water bath
Observe at 60 secs
5 second intervals (performed 10 secs in lab)
Normal values for ACT test
What is the purpose of diatomaceous earth in the ACT test?
Causes activation of coagulation pathways
Why is ACT a better method than other tests?
It is more sensitive, more narrow window of results
What are other methods to determine coagulation time?
Buccal mucosa bleeding time
Capillary tube method
Lee- White method
What is the indication for an ACT test?
platelet abnormalities such as a low platelet estimate on the differential
Indication for fibrinogen test
General inflammatory response, verify inflammation
How is a fibrinogen test done?
Collect a pair of blood samples in EDTA
Make 2 crit tubes
determine TSP on tube 1
place tube 2 in a water bath 56-58 for 3 mins
determine TSP of tube 2
Subtract TSP of tube 2 from Tube 1.
Fibrinogen is measured in mg/dL, how do you convert from g/dL?
Multiply g/DL by 1000.
How do you calculate absolute retic count?
%retics X total RBC count
Corrected retic count, importance?
observed retics % X observed PCV/normal PCV. Should be interpreted according to the degree of anemia.
corrected retic %/maturation time for observed PCV
How is a reticulocyte count done?
A few drops of EDTA blood in small test tube
Add an equal volume of NMB. Let sit for 20 mins.
Make a thin blood film
count 1000 RBC's and record the # of retics seen
How is a platelet count done?
Use unopette to dilute 20 ul of blood.
Let stand 10 mins before charging hemocytometer
Charge hemocytometer, let sit in moist petri dish for 10 mins.
Observe under 40X, low light. Look in center primary square and count platelets.
Must do platelet count within _______ of collection.