Flashcards in Exam 1: Lecture 1 Deck (30)
purple top blood tube
green top blood tube
yellow top tube (with and without separator)
what 3 interfering substances within a sample cause analytical error?
hemolysis - red/pink: caused by free hemoglobin in the blood, seen when animal is dying
lipemia - pink: gives you false readings on all your electrolytes
increased bilirubin - yellow: extra pigment will cause artificial inflation of test values
hemolysis and main intercellular ion of RBCs
the main intercellular ion in RBCs is K. when many RBCs are lysed in solution you will have a lot of K.
when RBCs stack like coins caused by excess fibrinogen and protein
when RBCs clump together due to excess immunoglobulins and complement - never cool. this happens when body is attacking its own RBCs.
occurs in a blood sample when animal has not been fasted. it can dilute out your electrolytes (Na, K, Cl). This is bad bc if your K reaches a certain level, it will cause cardiac distress.
whats in the buffy coat of an HCT tube?
leukocytes and platelets
what is fibrinogen?
an acute phase protein; which means during inflammatory response it goes up.
- its present in plasma, not serum (bc its used up during the clotting processes)
- this is especially important in large animals bc they dont have as dramatic of a nucleophilic response and therefore depend on fibrinogen more than small animal
little spots of hemmorhage on inner ear, ventrum, etc. tells you there is a little hemorrhage going on
spots of hemorrhage that can be up to a cm in diameter (a little bigger than petichae)
bigger areas of hemmorhage
liquid portion of the blood after its spun. its mostly water.
- you will give patients transfusions to give the patient clotting factors and to inhibit the activation of the co ag cascade, usually done in an emergency
what two coag factors come together to form a clot?
2 = thrombin 1 = fibrin
packed cell volume: a measure of the spun RBCs
SAME AS HCT!!
Roughly between 30 - 50%
plasma color: dogs and cats should be colorless, horses and bovines: colorless or pale yellow
mean cell volume - describes the average SIZE of RBCs
dogs have the largest RBC
goats have tiny RBC
RDW - red cell distribution width
describes how much variation there is in RBC size
a high RDW means you have a ton of little tiny and really big RBC
mean cell hemoglobin concentration = ratio of the hemoglobin to the number of RBCs
(Hgb / PCV) x 100
decreased MCHC (hypochromic) can be caused by: regenerative anemia and Fe deficiency
increased MCHC (hyperchromic) can be caused by: ALWAYS an artifact caused by hemolysis or interference with Hgb measurement due to: lipemia, heinz bodies and very extreme WBC elevation
things that will mess up MCHC (cause an increased MCHC)
indicative of hemolysis caused by:
2. heinz bodies
3. ver high WBCs
things that can cause errors in blood cell measurements:
3. heinz bodies
4. nucleated erythrocytes (will increase your WBC count)
5. Pb toxicity
how do you calculate a corrected leukocyte count?
corrected WBC count = (measured WBC count x 100) /100 + nRBC
where nRBC = number of nRBC /100 WBCs
ex: dog has 50 nRBC /100 WBC and measured WBC count of 9000/ml
corrected WBC count = (9000 x 100) /150 = 6000/ml
difference between a nRBC and a lymphocyte
an nRBC is nucleated but will have a complete rim of cytoplasm and the cytoplasm is more eosinophilic. a lymphocyte is little cytoplasm at all.
when you can trust a machine with cat platelets?
exam Q: a cat has no platelets, what should you do?
make a BLOOD SMEAR to check, bc you can NEVER trust an automated analyzer.
bc cat platelets are huge and like to clump
when do you use a new methylene blue stain?
chronic inflammatory disease or Fe deficiency anemia and prussian blue stains
anytime you have inflammation, the body will hide iron in the liver, spleen or bone marrow bc the body thinks you have a bacterial infection. however this will prevent you from being able to utilize iron to make hemoglobin
tap water is refractile meaning that as you focus up and down on teh cell, the artifact "flashes" in one plane of focus, it may appear dar, while in another plane it appears light.