Lab Exam (From review sheet) Flashcards
What is a hematology assay used for?
Assays are used to diagnose blood disorders such as anemias and other general diseases
CDCs: when and why
CBCs are performed when a patient feels symptoms such as weakness, fatigue, fever, bleeding, etc. The purpose is to see what specifically is wrong with the patient
CBC: components
a. RBC
b. WBC
c. Platelet
d. MCV
e. MCH
f. MCHC
g. PTT
h. aPTT
Reticulocyte units
Normally in %, but also in cells per liter for ARC
Sedimentation rate: what does it measure
Used to see if any disease affects the plasma proteins
Sedimentation rate: units
Millimeters
Sedimentation rate: factors that affect it
gender, habits like diet and drug use
Sedimentation rate: Prefered method
Westergren method
Sedimentation rate: Men Value
Male: 0-15mm
RBC Indices: MCV range
MCV: 80 to 100 femtoliter
Most important concern when performing a phlebotomy?
The main concern when taking a person’s blood sample is performing diplomacy and ethical behavior
Where do you place tourniquet
The tourniquet should be placed below IV site on the bicep and should be on for no longer than a minute
The order of the draw
Coagulation test (Light Blue top), Chemistry test (Red top), CBC test (Lavender top)
Tube types: what they’re for
Blue top: Coagulation
Red Top: Chemistry
Lavender: CBC
Tube types: what they’re for
Blue top: Coagulation
Red Top: Chemistry
Lavender: Hematology
Yellow: Microbiology
Common veins for phlebotomy
Median cubital vein
Where to draw/not draw blood sample
Draw blood on opposite arm above the IV site, don’t puncture at IV site
When to remove tourniquet
Remove the tourniquet one last tube starts filling
How to handle needle
Secure with 3 fingers angled at 15 degree angle entering 3/4s of the needle in the skin
Criteria for rejection of blood sample
a. Incorrect specimen collection container.
b. insufficient specimen quantity.
c. Transported incorrectly.
d. Inadequate fixative.
e. specimen too large for container.
f. Incorrect media.
g. Specimen stability compromised
Hematocrit
volume occupied by RBCs in a given in a volume of blood, expressed in percentage of the whole blood sample
Hemoglobin
the component of the RBC that transports O2 from lungs to tissues and CO2 from tissues to lungs
Hematocrit calculation
RBC * MVC / 10 = HCT
hematocrit value: infant
Newborn: 53-65 %
hematocrit value: Child
Infant: 30-43 %
hematocrit value: Women
37-47%
hematocrit value: Men
42-52%
What is the rule of 3?
Hematocrit = 3*hemoglobin
Hemoglobin= 3 * RBC
Hemoglobin types
Oxyhemoglobin: with O2
Carbaminohemoglobin: with CO2
Methemoglobin: with ferric Iron
Carboxyhemoglobin: with CO
Sulfhemoglobin: with S
Which types of hemoglobin doesn’t carry O2
Methemoglobin: with ferric Iron
Carboxyhemoglobin: with CO
Sulfhemoglobin: with S
Hemoglobin affinity
250x stronger for carbon monoxide than O2
Hemoglobin value: infant
13.5-19.5
Hemoglobin value: Child
11.5-15.5
Hemoglobin value: Women
12-15
Hemoglobin value: Men
13.5-18
MCV calculation
MCV: HCT/RBC *10
MCH calulation
MCH: Hgb/RBC * 10
MCHC calculation
MCHC: Hgb/HCT *100
What does stain for Reticulocytes
Stains the RNA and ribosomes that are still present in reticulocytes
Reticulocyte calculation
of reticulocytes counted/1000*100
Sedimentation rate: Women Value
Female: 0-24mm
Sedimentation rate: Child Value
Child: 0-24mm
RBC Indices: MCH range
MCH: 27 to 31 picograms/cell
RBC Indices: MCHC range
MCHC: 32 to 36 grams/deciliter
