Mod 5 Flashcards
begins in the laboratory when a test is ordered and ends when testing begins
preanalytical (before analysis)
values which patient results are compared to
Reference range
resting metabolic state of the body early in the morning after fasting for approximately 12 hours
Basal state
ideal for establishing reference ranges on inpatients
Basal state
Basal state is influenced by a number of physiologic patient variables:
Age
Gender
Conditions of the body that cannot be eliminated
specimens that are not basal-state specimens and may have slightly different reference ranges or normal values.
Outpatient
Age increase
RBC WBC
Age decrease
Kidney functions (creatinine clearance
Altitude increase
RBC
hemoglobin
hematocrit
uric acid
C-reactive protein
Altitude decrease
urinary creatinine
plasma renin
take weeks to adapt to high elevations/altitude; however, they adapt to return to sea level within days.
Analytes
decrease in body fluid
Dehydration
blood components that cannot easily leave the bloodstream
hemoconcentration
Dehydration increase
o RBC
o Enzyme
o Iron
o Calcium
o Sodium
o Coagulation factors (clotting
factors)
Strictly no ingestion of food approximately
8-12 hours overnight
nothing by mouth
nil per os
fasting beyond 12 hours can cause serious health problems, such as
electrolyte imbalance and heart rhythm disturbances
Diet increases
Ammonia, urea, and uric acid
Cortisol and Adrenocorticotropic hormone (ACTH)
Glucose
Lipid
Triglycerides, certain liver enzymes,
and other liver function analytes
Diet decreases
hemoglobin
electrolyte imbalance
Long term starvation increases
Creatinine
Ketone
Uric acid
Long-term starvation decreases
Cholesterol
Triglycerides
Urea
Factors that play a role in DIURNAL VARIATIONS
- Posture
- Activity
- Eating
- Being awake or asleep
- Daylight and darkness
increase at night and decrease during daylight hours
Melatonin
peaks around 8 am
Cortisol
peaks at pre-dawn hours of the morning during sleep.
Renin and Thyroid-stimulating hormone
peaks in the morning
Aldosterone, Bilirubin, Cortisol, Hemoglobin, Insulin, Iron, Potassium, Testosterone, RBC
normally lowest in the morning
Blood levels of Eosinophils, Creatinine, Glucose, Growth hormone, Triglycerides, and Phosphates
Drugs can also interfere with the actual test procedure, causing
false increases or decreases in test results.
drug may compete with the test reagents causing
falsely low or false-negative result
drug may enhance reaction, causing
Falsely high or false-positive result.
Chemotherapy drugs decrease
WBC, platelets
Most drugs that are toxic to liver increases
AST, ALP, LDH
Most drugs that are toxic to liver increases
AST, ALP, LDH
Most drugs that are toxic to liver decrease
Vitamin B12
Steroids and diuretics increase
Amylase, lipase
Thiazide diuretics increase
Calcium, glucose
Thiazide diuretics decrease
Sodium & potassium
Drugs that interfere with BLOOD TESTS should be stopped or avoided
4 to 24 hours prior to obtaining blood samples for testing
Drugs that interfere with the URINE TESTS should be
avoided for 48 to 72 hours prior to the urine sample collection.
Exercise increases
- Glucose
- Creatinine
- Insulin
- Lactic acid
- Total protein
Potassium
- Creatine kinase (CK)
& Lactate dehydrogenase
Cholesterol
Excercise decreases
Arterial pH
* Carbon dioxide
Fever increases
Insulin
Glucagon
Cortisol
Higher level in males after sexual maturity
RBC, hemoglobin and hematocrit values
Intramascular injection increases
creatine kinase (CK)
skeletal muscle fraction of LDH
condition characterized by increased bilirubin (a product of the breakdown of RBC) in the blood
Jaundice (icterus)
relating to or marked by jaundice and is used to describe serum, plasma, or urine specimens that have an abnormal deep yellow to yellow-brown color due to high bilirubin levels.
icteric
lying down on the back to an upright sitting or standing position
supine
Supine position increases
- Aldosterone
- Calcium
- Iron
- Cholesterol
- HDL
Standing position increases
RBC
Potassium ion levels
Pregnancy increases
body fluids
Pregnancy decreases
diluting effect on RBC, RBC count
Patients who smoke prior to specimen collection may increase
- Cholesterol
- Cortisol
- Glucose
- Growth hormone
- Triglycerides
- WBC count
Chronic smoking increases
- RBC count
- Hemoglobin levels
Smoking decreases
immunoglobulins IgA, IgG, IgM
Smoking increases immunoglobulin
IgE
Stress increases
ACTH
Catecholamines
Cortisol
Stress decreases
Iron
Temperature and humidity increases
plasma volume and influencing its composition
areas are more susceptible to infection, and
contain dyes that can interfere with testing.
Tattooed areas
hardened
sclerosed
clotted
thrombosed
swelling caused by the abnormal accumulation of fluid in the tissues.
Edema
swelling or mass of blood (often clotted) that can be caused by blood leaking from a blood vessel during or following venipuncture.
hematoma
obstruction or stoppage of normal lymph flow
lymphostasis
Impaired lymph flow makes the arm susceptible to swelling, called
lymphedema
catheter that is placed in an artery
arterial line (A-line or Art-line)
arterial line (A-line or Art-line) is most commonly placed in
radial artery
used to collect blood gas and other blood specimens and for the administration of drugs such as dopamine.
ARTERIAL LINE
permanent surgical connection of an artery and vein by direct infusion (fistula), resulting in a bulging vein, or with a piece of vein or tubing (graft) that creates a loop under the skin
Arteriovenous shunt, fistula, graft
direct infusion
fistula
piece of vein or tubing
graft
catheter or cannula connected to a stopcock or a cap with a diaphragm (thin rubber-like cover) that provides access for administering medication or drawing blood
HEPARIN or SALINE LOCK
“of, pertaining to, or within a vein.”
INTRAVENOUS (IV) SITES
catheter inserted in a vein to administer fluids.
IV
If both arms have an IV line, it is preferred that the specimen be collected by
capillary puncture
Blood specimens should not be collected from a known previous IV site within
24 to 48 hours
central vascular access device (CVAD), also called an
indwelling line
consists of tubing inserted into a main vein or artery.
central vascular access device (CVAD)
Types of CVADs
Central venous Catheter (CVC)
Implanted port
Peripherally Inserted central catheter (PICC)
line inserted into a large vein
exit end is surgically tunneled under the ski to a site several inches away in the chest
short lengths of capped tubing protrude from the exit site, which is normally covered with a transparent dressing
Central venous Catheter (CVC)
small chamber attached to an indwelling line that is surgically implanted under the skin and most commonly located in the upper chest or arm.
Implanted port
inserting a special needle through the skin into the self-sealing septum (wall) of the chamber.
The site is not normally covered with a bandage when not in use.
Implanted port
line inserted into the peripheral venous system (veins of the extremities) and threaded into the central venous system.
Peripherally Inserted central catheter (PICC)
Adhesive Allergy.
What to do?
place a clean, folded gauze
Wrap the bandage (remove it in 15 minutes.)
hold pressure for 5 minutes in lieu of applying a bandage.
Antiseptic Allergy
What to do?
Use alternate antiseptic available in the lab
Latex Allergy
What to do?
Ask the patient if he or she has allergy when exposed to latex
Use non-latex materials
EXCESSIVE BLEEDING
What to do?
✓ Apply pressure onto puncture site until the bleeding stops
✓ Appropriate personnel should be notified
Contributing factors to fainting:
o Anemia
o Dehydration
o Emotionalproblems
o Fatigue
o Hypoglycemia
o Hyperventilation
o Medications
o Nausea
o Needle phobia
o Poor compromised breathing
SUDDEN FAINTNESS OR LOSS OF CONSCIOUSNESS DUE TO A NERVOUS SYSTEM RESPONSE TO ABRUPT PAIN, STRESS, OR TRAUMA
VASOVAGAL SYNCOPE
signs of fainting
o Paleness
o Perspiration
o Hyperventilation
oVertigo
o Dizziness
o Light-headedness
o Nausea
NAUSEA VOMITING
✓ Do not attempt to draw blood until the experience subsides.
✓ Discontinue the procedure if a blood draw is in progress.
excessive, deep, blind, or lateral redirection of the needle in the puncture site
PROBING
tiny, non-raised, red spots that appear on the patient’s skin when a tourniquet is applied
Petechia
most common complication of venipuncture.
HEMATOMA FORMATION
caused by blood leaking into the tissues during or following venipuncture and is identified by rapid swelling at or near the venipuncture site.
HEMATOMA FORMATION
is an adjective used to describe an adverse condition brought on by the effects of treatment
IATROGENIC
Blood loss to a point where life cannot be sustained
exsanguination
most often associated with deep or blind probing, especially in the area of the basilic vein, which is in close proximity to the brachial artery
INADVERTENT ARTERIAL PUNCTURE
Possible causes of a main nerve injury
• Poor site or improper vein selection
• inserting the needle too deeply or quickly
• movement by the patient as the needle is inserted
• excessive or lateral redirection of the needle, or blind probing while attempting
venipuncture
Signs of Possible Nerve Injury
• EXTREME PAIN
• BURNING OR ELECTRIC-SHOCK
SENSATION
• NUMBNESS OF THE ARM
• PAIN THAT RADIATES UP OR DOWN THE ARM
contents of the collection tube are in contact with the needle while the specimen is being drawn.
Reflux
trapping of blood in an extremity by compression of veins
venostasis
a decrease in the fluid content of the blood with a subsequent increase in nonfilterable large molecule or protein-based blood components.
hemoconcentration
increase in levels due to hemoconcentration:
- Red blood cells
- Albumin
- Ammonia
- Calcium
- Coagulation factors
- Enzymes
- Iron
- Potassium
- Cholesterol (increases up to 5% after 2 minutes of tourniquet application and up to 15% after 5 minutes)
- can increase potassium levels up to 20%
- reported to be responsible for a third of all elevated potassium and
may also increase lactate and phosphate levels
Vigorous hand pumping (making and releasing a fist)
RBCs are damaged or destroyed and the hemoglobin they contain escapes into the fluid portion of the specimen.
HEMOLYSIS
Hemolysis can erroneously elevate:
- Ammonia
- Catecholamines
- Phosphate
- Creatine kinase
- Iron
- Magnesium
- Potassium
Hemolysis can erroneously decrease:
- RBC count
should be filled until the normal amount of vacuum is exhausted.
Evacuated tube system tubes
Excess EDTA can
shrink RBCs
alter the staining characteristics
Excess heparin
interfere with the testing of some chemistry analytes.
Excess sodium fluoride
result in hemolysis of the specimen.
Underfilled coagulation tubes
produce erroneous results.
