balances and centrifuges must be callibrated once a year
balances usually have units in grams or milligrams
the most common type of balance used in the lab is the analytical balance, which usually goes out to milligrams
balances are used to calibrate pipettes
balances should be kept in low traffic areas since they are sensitive and should not be moved
centrifuges are used to separate particles from liquids in a suspension
a centrifuge must be balanced before starting
the matrix of a specimen refers to the qualities of specimen, including viscosity, color, clarity, and source
the viscosity is the thickness of the specimen
plasma is thicker or more viscous than water
specimen considerations include the matrix, condition of specimen, collection, and storage
the serum/plasma should be a pale yellow in color
the clarity of the specimen should be clear
the viscosity of the specimen should be similar to maple syrup
collection considerations include using the proper tube, prepping the patient properly (eg. lipid, glucose must be fbs), temperature requirements (eg. ammonia must be put on ice and spun ASAP); photosensitivy requirements
storage considerations - most common: refrigerate after spinning down and removing serum
protect from light using special aliquot
some specimens frozen with special aliquot
least common - keep specimen at RT
add to specimen (e.g. HCl to urine for calcium testing)
the QC must have the same matrix as the patient specimen, but clarity doesnt have to be the same
plasma after spinning down looks peach to red cherry; some analytes cannot be run as RBC contents have been released; specimen is said to be _______
hemolysis; hemolyzed
if patient had fatty meal, serum/plasma may look hazy/cloudy; some analytes cannot be run
lipemic
some patients with liver disorders have issues breaking down RBC; may have bilirubin in blood; looks greenish/brown; called ______; specimen is said to be ______
icterus; icteric
if the patient is very and on anticoagulant, the blood takes longer to clot in tube; if spun too early what occurs?
serum coagulates, or fibrin strands present
phlebotomy is the act of obtaining a blood specimen by puncturing vein with needle
the preferred site for phlebotomy is the antecubital fossa
the ante cubital fossa is anterior of the elbow
the tourniquet should be applied 4 inches above the site in order to stop venous blood, causing the vein to distend
direct pressure should be applied to the site until it stops bleeding
a gauze with tape should be applied for 20 minutes
We cannot draw blood from an IV site
Only nurses can draw blood through an IV site
veins move because as one ages, the collagen degrades
We cannot draw blood from the side of a mastectomy
What to do if patient has IV
draw from other arm
use the back of the hand
tourniquet and draw site must be distal to the IV or below
cannot draw proximal or above IV
If only the arm with an IV is available, you must as nurse to shut off IV, wait 20 minutes, and waste first tube of blood
The order of draw is blood cultures, light blue, red, marble, green or marble green, lavender, grey, pink/brown/dark blue
sodium citrate for coagulation studies
light blue
if light blue is first tube to be drawn, youmust waste a red tube first
no additive
red
SST
marble or mustard yellow plastic
sodium/lithium heparin
green
liquid used to dilute specimen; what's added to specimen
diluent
liquid used to reduce concentration of analyte we are looking to quantify