L1: Pe-analytical Considerations Flashcards
resting metabolic state of the body early morning after appx. 12 hrs fasting
basal state
what are the physiological variables that influence lab test results
age
altitude
dehydration
diet
diurnal variation
drug therapy
exercise
gender
jaundce
intramuscular injection
position
pregnancy
smoking
stress
temperature & humidity
what values are higher in newborn
RBC , WBC
This function decreases with age
kidney function
this are elevated at higher altitude
RBC
Hemoconcentration in dehydration elevates?
RBC, enzymes, Calcium, Sodium, Iron
in terms of diet:
- lipids increase with ingestion of ____
- ______ increase due to excessive drinking of water
- glucose increase with the ingestion of _______
- ammonia, urea increases in patients on _____
- fatty meals
- electrolytes
- carbohydrates
- high-protein diets
Tests that require Fasting
FBS
GLucose Tolerance Test
Triglyceride and Lipid Panel
Gastrin
Insulin
Aldosterone & Renin
Electrolytes
melatonin levels are affected by ____. when doe sit increase and decrease?
affected by light
increase - night
decrease - day
Renin & Thyroid-Stimulating Hormone (TSH)
-> peak levels in the ____ hours of the morning during ____
predawn; sleep
cortisol has peak levels later in the _____, around what time?
morning; 8am
exhibit diurnal variation with highest levels in the _____
morning
________ drugs can cause a decrease in blood cells, especially _____ and ____
Chemotherapy; WBC; platelets
drug therapy increase levels of liver enzymes. what are these liver enzymes?
- Aspartate Aminotransaminase (AST)
- Alkaline Phosphatase (ALP)
- Lactide Dehydrogenase (LDH)
When exercising, what increases and decreases?
Arterial pH, PCO2 levels - decrease
increase:
- glucose
- Potassium
- Skeletl muscle enzymes: creatine kinase and Lactide Dehydrogenase
what increases in fever?
- hormones: glucagon, insulin
- cortisol
these values are higher for males than for females
RBC, Hemoglobin, Hematocrit
intramuscular injection increases levels of ___ and the skeletal muscle fraction of ____
creatine kinase; Lactide Dehydrogenase
it refers to the presence of Jaundice
icteric
this physiological variable interferes with chemistry tests based on color reactions
Jaundice
supine to upright position: what increases and decreases?
decrease: plasma volume
increase: protein, potassium
pregnancy lowers ____
RBC
Chronic smoking decreases and increases what values?
- decrease: pulmonary function, concentration of immunoglobulins
- increase: RBC, hemoglobin levels
stress increases and decreases what values?
- increase: cortisol, WBC, adrenocorticotropic hormone (ACTH), catecholamine
- decrease: serum iron levels
common preanalytical errors before collection
- misidentification of patient
- wrong lab test ordered
3, Inadequate patient preparation
Common Preanalytical Errors During collection
- wrong container/ additive
- short draw/ wrong anticoagulant/ blood ratio
- hemolysis due to uncorrect technique
- prolonged tourniquet time
Common Preanalytical Errors after collection
- Inadequare mixing/ clots
- Mislabeling of specimen
- Improper Transport: exposure to light, extreme temp, delayed delivery
- Processing Errors: incomplete centrifugation, incorrect log-in, improper storage, improper aliquoting
problems encountered in burns, scars, tattoos
healed burns, extreme scarring: impaired circulation
newly burned areas: painful and susceptible to infection
tattoos: impaired circulation, susceptible to infection, dye may interfere with testing
hard and cord-like; occulated or obstructed veins
Damaged veins
thrombosed vs sclerosed
thrombosed - clotted vein
sclerosed - hardened vein
in damaged veins, ____ is caused by numerous venipunctures
scarring
what to do in damaged veins?
- choose another site if possible
- draw below (distal to) damaged veins
_____ may yield incorrect test results due to contamination with tissue fluid
edema
in edema;
- veins are ______ to locate
- tissue is often ___ and easily injured by ______ and ____ application
- _____ may be prolonged
harder
fragile; tourniquet, antiseptic
healing
it is the swelling/ mass of blood that can be caused by blood leaking from a _______ during/ following venipunc
hematoma; blood vessel
surgical breast removal
mastectomy
lymph node removal causes _____
lymphostasis
it is the obstruction/ stoppage of normal lymph flow
lymphostasis
mastectomy is susceptible to ___
what happens when you apply tourniquet to the arm of a patient that had mastectomy?
infection
can cause injury
difficulties encountered in patients with obesity?
What to do?
what veins are allowed for venipuncture?
- deep veins and difficult to find
- proper tourniquet selection and application
- median cubital vein, cephalic vein
to locate the cephalic vein of an obese patient, rotate the patient’s arm so that the hand is ___
prone
it is a tube inserted into a vein or artery
Vascular Access Device
TRUE OR FALSE: Never apply torniquet or perform venipunctureon an arm w/ VAD
TRUE
It is also known as A-line or Art line
Arterial Line
it is a thin catheter that is placed in an artery.
function?
arterial line
- for continuous bp monitoring, and blood gas analysis
arterial line is most commonly placed in a ____
radial artery
a surgical procedure that fuses artery and vein
arteriovenous shunt/ AV fistula
purpose of AV fistula?
- hemodialysis treatment
- erosion of arterial treatment
function of Heparin or Saline lock. where is it often placed?
- administering medication, drawing blood
- vein in th lower arm above the wrist
it is a thin plastic tube / catheter inserted in a vein to administer fluids
intravenous (IV) sites
Heparin or Saline lock can be left in place for up to _____
purpose of heparin/ saline?
what should be drawn first?
drawing what specimens is not recommended
48 hours
to prevent clotting
5mL discard tube
coagulation specimens
What to do when there is an IV site:
- draw blood ____ the IV site
- IV is in one arm
- IVs in both arms/ other arm is unavailable
- below
- do it on the other arm
- do capillary puncture
blood should not be collected from a previous known IV site ___ to ___ hours of the time the IV was discontinued
28-48
it is a needleless closed blood sampling device and is sometimes connected to an ______ or ______ catheter
blood sampling device; arterial or central venous catheter
this device reduces the chance of infection, prevent needlesticks, and minimize waste associated with line draws
blood sampling device
indwelling line, consists of tubing inserted into a main vein or artery
central vascular access device (CVAD)
Line inserted into a large vein such as subclavian and advanced into the superior vena cava
central venous catheter (CVC)
surgically implanted disk-shaped: chamber attached to the indwelling line
where is it placed?
implanted port
placed on the upper chest just below the collarbone
what to do: Latex allergy
- use non latex gloves, bandage, tourniquet
Line inserted into a vein in an extremity and threadded into a main vein leading to the heart
Peripherally Inserted Central Catheter (PICC)
what to do: adhesive allergy
- place folded gauze square over the site; remove it after 15 minutes
- instruct patient to hold pressure for 5 minutes in lieu of applying a bandage
what to dod: antiseptic allergy
alternative antiseptic should be readily available
what to do: excessive bleeding
maintain pressure over the site til it stops
if the bleeding continues after 5 minutes, notify appropriate personnel
TRUE OR FALSE: patient can be dismiss immediately after venipuncture
FALSE. do not dismiss a patient until bleeding has stopped
it is the temporary loss of consciousness due to insufficiency of blood flow to brain
fainting/ syncope
sudden faintness/ loss of consciousness due to a nervous system response to abrupt trauma, stress, pain
vasovagal syncope
2nd most common complication in venipuncture
vasovagal syncope
signs of syncope
pallor (paleness)
hyperventilation
formation of beads of sweat on the forehead
indication from the patients that he/she is experiencing vertigo (a sensation of spinning), dizziness, lightheadedness or nausea
what to apply to a patient who experienced syncope during venipuncture
apply cold compress or wet washcloth to the forehead and back of the neck
patient is nauseous or show signs similar to fainting?
- blood draw should not be attempted/ discontined until feeling subsides
- Ask the patient to breathe slowly and deeply
- Apply a cold, damp washcloth or other cold compress to the patient’s forehead
what to do: pain
- remove needle immediately
signs of nerve involvement?
Marked or extreme pain, numbness of the arm, a burning or electric-shocksensation, or pain that radiates up or down the arm
Pain persists after needle removal?
apply ice pack to the site
- tiny, non-raised red (or purple) spots that appearon the patient’s skin when a tourniquet is applied.
- minute drops of blood that escape the ____
- result of?
Petechiae
capillaries
platelet abnormalities, capillary wall defects
what to do: seizures and convulsions
- Discontinue the draw immediately
- Hold pressure over the site
- Do not attempt to put anything into the patient’s mouth
- Notify the appropriate first-aid personnel
it is the most common complication in venipuncture
hematoma formation
swelling or mass of blood that can be caused by blood leaking from a blood vesselduring or following venipuncture
what to do?
hematoma formation
- first 24 hrs: apply ice (20-30 mins), after 24 hrs: apply warm compress
causes of hematoma
Excessive or blind probing
Inadvertent arterial puncture
Fragile vein ( too small for the needle size)
Needle penetrates through the vein
Needle is partially inserted
Needle is removed while the tourniquet is still on
Pressure is not adequately applied after venipuncture
blood loss due to blood draw
Iatrogenic Anemia
In Iatrogenic Anemia, the patient’s life is threatened if?
if more than 10% of a patient’s blood volume is removed at one time
Deep or blind probing, in the area of the basilic vein (close proximity to the brachial artery)
INADVERTENT ARTERIAL PUNCTURE
signs of inadvertent arterial puncture
what to do?
- rapidy forming hematoma
- blood filling the tube very quickly
- terminate venipuncture immediately
- apply direct forceful pressure to the site for atleast 5mins until it stops
improper vein selection can cause what injury?
nerve injury
Reflux (flow back) into the patient’s vein from the collection tube during thevenipuncture procedure
what to do?
refluc of additive
patient’s arm must be kept in a downward position
- Numerous venipunctures in the same area over an extended period of time
- Blind probing and improper technique when redirecting the needle
vein damage
Decrease in fluid content or plasma volume
it is caused by?
hemoconcentration
stagnation of the normal venous blood flow because oftorniquet application
RBCs are damaged or destroyed and the hemoglobin escapes into thefluid portion of the specimen
hemolysis
in hemolysis, what does this indicates:
- serum or plasma appears pink?
- dark pink to light red?
- dark red?
- slight hemolysis
- moderate hemolysis
- gross hemolysis
●Drawing blood through a hematoma or from a vein with a hematoma
● Failure to wipe away the first drop of capillary blood (alcohol residue)
● Forceful aspiration of blood during a syringe draw
● Forcing the blood from a syringe into an evacuated tube
● Frothing of blood caused by improper fit of the needle on a syringe
● Horizontal transport of tubes● Mixing additive tubes vigorously
causes of hemolysis
Dripping perspiration into capillary specimens can cause what?
specimen contamination
using wrong antispetic and not following proper antispetic procedure may cause?
specimen contamination
in a wrong/ expired collection tube, there may be formation of?
microclots
blood filling the tube very slowl can indicate that bevel is?
Bevel Partially into the Vein
vein disappears as soon as the tube is engaged or when the tourniquet is removed
collapsed vein
