final lecture Flashcards
serum
the liquid portion of blood after clotting has occured
plasma
the liquid portion of blood without the cells when blood is spun down in a tube with anticoagulant
what is the primary function of the anticoagulant sodium fluoride?
antiglycolytic agent
inhibits glycolysis
choice of anticoagulant for hematology
EDTA
choice of anticoagulant for coagulation
sodium citrate
choice of anticoagulant for chemistry
heparin
why is freezing whole blood not normally recommended to preserve a specimen
the red cells will lyse causing hemolysis
what are the two primary reasons patients are placed in isolation rooms?
to protect healthcare staff and visitors from infections
to protect an immunocompromised patient
how does EDTA prevent clotting?
by binding/chelating calcium in the form of potassium or sodium salt
how does heparin prevent clotting?
inhibits conversion of prothrombin to thrombin
what are the capillary puncture sites on an adult?
the index, middle, or ring finger.
where would you not want to perform capillary puncture on adult?
the middle of the finger
what is the preferred area on a finger for puncture?
perpendicular to the fingerprints on the outside of the finger
what is a hematoma and what causes it?
- collection of blood under the skin - indicative of poor technique
- going through a vein
- partially inserting needle into vein
- grazing side of the vein
state the consequences of pushing a tube onto the needle before entering the patient’s vein.
loss of vaccum = no suction in tube
could contaminate tube
explain the purpose of removing the tube from the needle prior to withdrawing from the patient’s vein.
to release the vaccum in the tube
what are clot activators and some examples
substance that inhibits or enhances coagulation
ex. glass/silica/siliceous earth/ thrombin
explain the order of draw
the order of draw is the list of when to draw specific tubes in a specific order
why does the order of draw exist?
this exists to prevent the cross contamination of additives between tubes
what does a sclerosed vein feel like when palpated?
hard/cord like
should a sclerosed vein ever be used for veinipuncture?
no
what is edema?
swelling
what is fistula?
abnormal connection between artery and vein
why are fistulas important to consider when deciding on site selection for venipuncture?
they are used for dialysis patients, so cannot be used
explain what a bevel is & what abnormalities to look for
bevel is the slanted tip on hollow venipuncture needle
ex. bent/curved/shaved/burns/spurs
why are therapeutic drug monitoring tests often timed collection tests?
to measure the peak and trough levels because people metabolize drugs at different rates and to monitor the amount of drugs at certain times to maximize effectiveness and prevent toxicity
what is the name of the heel bone?
calcaneus
what does skin puncture blood most closely resemble?
arterial blood
explain why routine or strict isolation is used.
patient is isolated to prevent the spread of a communicable disease
what is the PPE used in routine and strict isolation?
gown, masks, gloves
explain protective or reverse isolation.
patient is isolated to protect from infection (severely immunocompromised patients)
what PPE is used in protective or reverse isolation?
gown, masks, gloves, hair net, booties
what does an abnormal retraction of a blood vessel wall during venipuncture cause?
vein collapse
what is the most important thing you should do before performing any type of specimen collection on a patient
wash hands and ID patient
what should you do if a patient refuses to let you collect a specimen on them?
let the doctor know
why should you allow the alcohol on the skin to dry properly before inserting the needle?
painful to patients and will lyse red cells
specimens should always be labeled where and when?
immediately after draw while still with patient
in regards to placement of the needle’s bevel in the vein, where would it fall that it would NOT allow collection of a blood specimen?
anywhere except facing up
needle penetrates through entire vein
went alongside vein
what are some possible techniques for transferring blood from a syringe into the proper collection tubes?
transfer device
describe the proper puncture site on an infants’ heel for skin puncture
medial or lateral on plantar surface
once a red stopper tube is spun down, what type of specimen does it yield
serum and clotted red cells
how much a collection site be prepared for collecting blood cultures?
cleaned with beta-dyne in non-overlapping circular motion
why is it important to take the extra steps for blood cultures?
to ensure sterility
in regards to therapeutic drug monitoring, the highest concentration of the drug during a dosing interval is called the ____
peak
explain the procedure for collecting specimens for a glucose tolerance test
- specimen drawn after pt. has fasted overnight
- pt. drinks glucose solution - mark time
- specimens drawn at 1 hr. intervals until complete (up to 5 hours)
does the order of draw change depending on the collection equipment you use ?
no
why should the site be warmed before performing skin puncture?
increases blood flow
why is controlling the depth of your lancet important during skin puncture?
if depth is not controlled could puncture bone or cause excessive bleeding
what step must you take, when doing a skin puncture, to eliminate tissue fluid contamination?
wipe away first drop of blood
what is a possible consequence of mixing a tube to vigorously?
hemolysis
when drawing a blood on a child, what are some extra steps you should take prior to venipuncture because of the age of your patient?
- gain child’s confidence
- -acknowledge child and parent
- ask for help to restrain child
what should you not do when performing specimen collection on a child?
- rush in
- do not ignore the child
- do not try to draw without a restrain on hand
why should a patient not pump their fist prior to venipuncture?
hemoconcentration
what is the most critical error a phlebotomist can make?
ID error
what indicator lets you know you are in the vein when performing a syringe draw?
flash of blood
what is the longest amount of time a tourniquet should be tied on a patient’s arm prior to venipuncture?
less then one minute
the alcohol prep pad used for cleaning a puncture site is what concentration?
70% isopropyl alcohol
give a couple examples of coagulation test
PT
PTT
fibrinogen
D-Dimer
what color tube is coagulation tests collected in?
blue
what is the anticoagulant used in the blue tubes?
sodium citrate
what should you do if your patient does not have an ID band on but is not conscious or able to ID themselves?
have a nurse put an ID band on
how should you handle questions from a patient about what tests you’re drawing and what they mean?
be as brief as possible and refer them to their doctor
do you ever draw a specimen from above an IV? why?
no because of the dilution that will occur in the sample
what should you do if you cannot draw on a patient’s arms because of multiple IV’s?
ask nurse to stop the IV wait 10 minutes then draw
why is it so important to mix anticoagulant tubes thoroughly after filling them?
mix equally with additives because micro-clots may occur
what is the smallest bore on a needle?
25
what is the largest bore on a needle?
18
small veins on a patient may collapse when what occurs?
blood drawn to quickly
what indication might alert you to the possibility that you have entered an artery during venipuncture?
bright red blood pulsing into the tube
what is the number one cause of hemoconcentration during venipuncture/
long tourniquet application
is water considered an acceptable thing to drink before a fasting sample is drawn?
yes
is coffee acceptable to drink before drawing of fasting sample?
no
is smoking acceptable before fasting sample?
no
normal serum appearance
clear straw color
normal plasma appearance
slightly opaque straw color
hemolyzed serum appearance
clear red
icteric serum appearance
brownish-yellow
lipemic serum appearance
milky-white
color tube of heparin
green
color tube of no additive
red
color tube of EDTA
lavender
color tube of sodium citrate
blue
color of tube of silicon serum separation material
red/gray/gold
color of tube sodium fluoride
gray
color of tube SPS
yellow
