Term | Definition |
what is venous reflux & how can it occur | when the blood is able to re-enter the vein - can occur if the tubing of a butterfly is moved or poor positioning of pt's arm |
where is the tourniquet placed | 3-4" above the antecubital space |
Invert | gently mixing blood w/an additive in a figure 8 motion |
what is the purpose of inverting | to mix the blood and additive appropriately and avoid microclots |
why should you fill tubes with additives completely | so the blood & additive ratio is correct - otherwise the sample will be compromised |
what are some reasons for a failed venipuncture | missed vein, poor needle placement, tube vacuum insufficient or expired, tourniquet is too tight or not tight enough |
what is lipemia | abnormal amount of fat in the blood - will appear milky or cloudy |
what is hemolysis and how can it occur | destruction of RBCs - releases hemoglobin into the liquid portion of the specimen. caused by shaking or dropping the tube |
how to choose appropriate gauge needle | by vessel and placement of vein and how much blood is needed |
what additive is in a lavender tube | EDTA |
what does a lavender top tube test for | hemotology - RBCs, WBCs, WBC differential, platelets, hematocrit, hemoglobin |
another term for butterfly needle | winged infusion kit |
CLSI | Clinical Lab Standard Institute - formerly NCCLS - sets phlebotomy standards |
what is the purpose of an additive | to preserve the integrity of the specimen and allow for accurate results |
what is a hematoma | swelling or bruising resulting from an accumulation of blood (at the puncture site) - broken blood vessels under the skin |
what is hemoconcentration | the plasma (H2O)seeps into the interstitial space so you have a higher concentration of formed elements |
why does hemoconcentration occur | can occur if you leave the tourniquet on too long |
why do you wipe away the first drop of blood in a capillary puncture | b/c it contains tissue fluid |
another term for capillary puncture | skin or dermal puncture |
what additive is in a light blue capped tube and what does it test | sodium citrate - coagulaton studies (fibrinogen and prothrombin) |
what may occur if a vacuum tube is under filled | the blood to additive ratio will be off which can cause inaccurate results |
gauge size for routine venipuncture | 21g |
gauge size for adults with smaller veins or children | 22g |
gauge size for children and difficult veins in adults | 23g = butterfly |
gauge size for infants and premies | 25g |
gauge size used with syringe | 20g |
what is PST - what color tube | plasma separator tube - light/mint green or black and green marble |
what tube is most commonly used for routine blood chemistry | SST - gold or red and black marble - contains thixotropic gel |
what additive is a gray tube - what does it test for | potassium oxalate, & sodium floride - glucose |
what additive is in mint/light green | lithium heparin with thixotropic gel |
what additive is in dark green | sodium heparin |
what tube is used for STAT chemistry tests | PST - mint/light green or green and black marble - contains thixotropic gel and lithium heparin |
what is the difference between plasma and serum | plasma has clotting factors, serum doesn't |
what is the purpose of the order of draw | to avoid cross contamination of additives |
how should you position your pt for venipuncture | sitting upright with back support, feet flat on the ground, arm straight and down resting on something |
blood chemistry | everything in the blood from birth i.e. hormones, lipids, glucose, proteins, enzymes, electrolytes, urea, lead, iron, prothrombin, fibrinogen, albumin,BUN, creatine, etc. |
serology | typically what is in the blood not from birth i.e. vaccinations, antibodies, toxicology, illness |
what tube would you use for a blood culture | sterile - need both anaerobic and aerobic broth |
veins within antecubital space | median cubital, cephalic (thumb side), basilic (pinky side) |
amber colored tube | used with photosensitive specimen |
vacuum tube method | used for routine blood specimen due to quick draw and multiple tube collection |
aliquot | portion of a specimen that is used for testing |
anticoagulant | additive used to prevent clotting |
found in PST and SST | thixotropic gel |
EDTA | ethylenediaminetetraacetic acid |
CBC | complete blood count |
volumes most commonly used for blood collection | 2-10ml |
capillary order of draw | EDTA, other additives such as heparin, SST, no additive tubes |
transportation of tubes | upright position |
capillary puncture | skin puncture method used to obtain small amounts of blood for testing; usually performed on fingertips |
amount of time a tourniquet kept on | 60 seconds |
plasma | liquid portion of whole blood that comes from a sample that contains an anticoagulant |
venipuncture | puncture of a vein to collect blood |
primary container | original container in which the specimen is collected |
tourniquet | used to distend veins to assist with venipuncture |
serum | liquid portion of blood that remains after blood has clotted |
guage | diameter of the lumen of a needle |
lancet | sterile disposable sharp-pointed blade used to puncture the skin to collect blood |
evacuated tube | collection tube which contains a vacuum that facilitates collection of blood |
constrict | narrowing of a blood vessel |
NCCLS | National Committee of Clinical Laboratory Standards |
microclot | small clots due to insufficient inverting |
fainting | syncope |
QNS | quantity not sufficient |
optimal results | using the most appropriate tubes for the best possible results |