Module 5: Special Collections Flashcards
blood smear
- thin film of blood spread into a microscopic glass slide
- used to microscopically examine blood
- venous blood or capillary blood
when must peripheral blood smear be prepared when collected in an EDTA tube
within 1 hr of collection
wedge method of preparing blood smears
- touching two slides at an angle of 30 to 35 degrees
- place edge of spreader slide in front of the drop of blood
- pull back the slide until it touches the blood
- let blood spread almost to the edges of the spreader slide
- push spreader slide toward clear end of the slide in one smooth motion
ways to collect blood for blood smear
- dermal puncture
- venipuncture using tube of uncoagulated blood, usually containing EDTA
how to get blood on slide if collecting with dermal puncture
- perform finger stick
- wipe away first drop of blood
- apply pressure to finger to obtain a free-flowing drop of blood
- allow blood to fall onto glass slide toward one end
how to get blood on slide if collecting with venipuncture
- use a safety device to access the blood or carefully uncap the tube behind a safety shield
- use disposable pipette or plastic dropper to remove the blood
- use applicator sticks or a capillary tube to place the drop on the slide
where should you place the drop of blood on a microscope slide
- 1/2 to 1 inch from the end of the slide
- do not place directly on the frosted end
should the frosted side of the microscope slide be facing up or down when using slides that have a frosted end
- up
- it is used to write pt information or to affix aliquot label
how should blood be distributed on a slide
- thicker at the drop point
- thinner on the opposite end
- tail with a feathered end that is slightly rounded
- should not touch the edges of the microscopic glass slide
- smooth without irregularities or holes
how to dry blood smear
- let it air dry before staining
- do not blow on it
blood cultures
- lab tests used to check for microbes in a blood sample
- assist in diagnosing conditions in a pt who has a fever of unknown origin (FUO)
how do you know how much blood to collect for blood cultures
- review the medical requisition form
- mark the bottle with the level of blood required
how to uncap and clean the blood culture bottle
- remove the protective cap, not the entire cap
- cleanse the top of the bottles with an antiseptic (alcohol)
how to cleanse the skin prior to venipuncture for a blood culture
- clean for 60 seconds using alcohol or chlorhexidine gluconate
- light friction using outward spiral technique
- clean around site to a diameter of 2 to 2.5 inches
- allow area to dry
- clean the area again using the same technique but with povidone-iodine for 30 to 60 seconds
- allow area to dry
which blood culture bottle should you collect first when using a butterfly needle
- aerobic
- anaerobic for other collection methods
when should the pt clench and unclench their fist
- clench: after the tourniquet is applied, before needle insertion
- unclench: as blood enters the tube or bottle
how long should you observe the venipuncture site for bleeding after releasing pressure
10 seconds
inborn errors of metabolism
- newborns screened for various metabolic and genetic disorders by analyzing blood on special filter paper
- assist in early detection
when is blood testing for newborn screenings performed
- before newborn is 72 hours old
- if it is obtained before the newborn is 24 hr old, a second specimen should be screened by 2 weeks of age
what conditions does newborn screening help detect
- cystic fibrosis
- hypothyroidism
- phenylketonuria (PKU)
- galactosemia
- other genetic disorders (biotinidase deficiency, sickle cell disease)
- infectious diseases (HIV, toxoplasmosis)
cystic fibrosis
mucous secretions that accumulate in various organs
hypothyroidism
decreased thyroid function
phenylketonuria (PKU)
- metabolic genetic disorder
- deficiency in hepatic enzyme phenylalanine hydroxylase
- causes permanent intellectual disability, seizures, delayed development, behavioral/psychiatric problems, mousy body odor, lightening of hair/skin, eczema
galactosemia
- lack of enzyme that breaks down galactose (a milk sugar)
- infant can slowly starve if left untreated
biotinidase deficiency
deficiency of enzyme that breaks down biotin
sickle cell disease
abnormal hemoglobin structure
what should you check newborn screening forms for
- expiration dates: substances within absorbent areas of filter paper can expire
- guardians phone number: in case any tests yield positive results
how do you collect blood for newborn screenings
- capillary puncture on infants heel
- allow large blood droplet to form
- touch the filter paper to the drop of blood to soak through completely in each circle
- circles must be totally saturated
how long should filter paper dry for newborn screenings
- air dry
- 3 hr
- room temperature
- away from direct sunlight and heat
how not to get blood on filter paper for newborn screenings
- avoid touching the skin with the card
- avid blotting or attempting to color in the circle with several blood drops: causes serum rings
- do not use capillary tubes: make filter paper rough and cause overabsorption
why might specimens for newborn screenings be rejected
- a circle is oversaturated
- all circles are not completely filled
- expired form is used
- form not received within 14 days of collection
- specimen is contaminated with foreign substance
- specimen not allowed to dry thoroughly
- circles have serum rings
autologous transfusion
pt donates their own blood for use for a transfusion or upcoming surgery
blood banks
- handle blood used in blood donations
- responsible for collection, processing, storing
- usually part of the lab
- work closely with regional blood centers that provide blood and blood products to hospitals
therapeutic phlebotomy
- intentional removal of blood to lower RBC or iron levels
- polycythemia vera: high RBC count
- hemochromatosis: high iron count
- performed by blood banks
how to hang bags during blood donation collection
- lower than pts arm
- gravity helps fill the bag
what to do and what not to do if blood donation bag only fills partially
- do: restart blood collection
- don’t: combine two bags
apheresis
- removal of blood plasma from pts body without withdrawing the blood itself
- separates blood into plasma and cells
- returns cells to pt body
- aka power red
plasmapheresis
removal of blood plasma from whole blood
requirements for blood donation
- at least 17 y/o (16 with parent permission in some states)
- weigh at least 110 pounds
- pulse: 50-100 bpm
- diastolic pressure: less than 100 mmHg
- temperature: less than 99.5 F
- hematocrit: over 38%
- donations at least 56 days apart (8 wks)
apheresis requirements for males
- age 17+ y/o
- weight 130+ lbs
- height 61+ in
apheresis requirements for females
- age 17+ y/o
- weight 150+ lbs
- height 65+ in
what is done before someone can donate blood
- get complete medical history
- mini-physical exam: temp, pulse, BP
- hemoglobin or hematocrit levels measured
- blood tested for HIV, AIDS, and hepatitis
what is done before someone can donate blood
- get complete medical history
- mini-physical exam: temp, pulse, BP
- hemoglobin or hematocrit levels measured
- blood tested for HIV, AIDS, and hepatitis
what questions are included in the medical history for pts wishing to donate blood
- sexual activity
- recent out-of-country travel
- use of medications
what must a pts hemoglobin be before they can do an autologous blood donation
at least 11 g/dL
when must a pts surgical procedure be scheduled for a pt to do an autologous blood donation
more than 72 hrs after the donation
iatrogenic anemia
- blood loss due to repeated venipunctures in a short period of time
- older pts, pediatric pts, pts who are underweight
why are older pts at risk of iatrogenic anemia
- medications may suppress bone marrow production
- decreases in nutritional intake
- significant amount of blood collected from different doctors
max amount of blood that can be taken from infants
- 1-5% of blood volume within 24 hrs
- 10% of blood volume over 8 wk period
max amount of blood that can be taken from adults
- 100 mL
- over that can cause decreased hemoglobin or hematocrit
how to calculate infant blood volume
- convert weight in lbs to kg: divide by 2.2
- convert kg to mL: multiply by 100
- convert mL to L: divide by 1000
what can iatrogenic anemia lead to
- shortness of breath
- fatigue
- need for blood transfusions
random urine collection
- most commonly performed urine test
- no preparations or time restrictions
- use a sterile specimen container
glucose tolerance test
- confirm pt is fasting, usually for 12 hr
- blood and urine tests should be performed at the same time
- collections every 1 to 2 hrs after finishing glucose solution
- drink glucose solution within five minutes
- document time specimen was collected
- if not collected on time, document reason and actual time it was collected
postprandial test
- void and then eat a meal
- specimen collection 2 hr after pt eats prescribed amount of carbs or glucose
- monitors effects of insulin dosage for those with diabetes
- screening tool
24-hour urine collection
- container that holds 3-4 L
- discard first-morning specimen and collection and specimens after that for 24 hrs
urine drug testing
- accuracy and privacy
- chain of custody form: everyone who handles the specimen must sign and date the form
clean-catch midstream urine collection
- use antiseptic that won’t damage genitals
- void small amount into toilet
- begin collection
- stop collection before urine flow stops completely
- finish voiding into the toilet
- used for culture and sensitivity testing
reagent strip for urine
- chemical analysis
- strip dipped into urine and analyzed
- use analysis chart to determine level of substance in the urine
- dispose of used strip in biohazard bag
saliva specimens
test for hormone, alcohol, and drug levels
sputum specimens
- collected from lungs, trachea, and bronchi
- pt takes deep breath and expectorates by coughing deeply into specimen container
- best to collect before or several hours after eating to prevent vomiting
- larger volume is available in the morning
fecal specimens
- determines bacterial infections, parasites, and occult blood
- dietary restrictions may be required
- keep sample at 98.6 F
semen specimens
- sperm count to assess fertility, DNA to prove identity in rape cases
- pt may need to refrain from ejaculation prior to specimen collection
- collect in sterile container, condoms contain spermicides
- keep specimen warm, protect from light
- return in 2 hr, 1 hr preferred
throat swab
- culture specimen, tests for strep throat
- wipe both tonsils, the throat, and all areas that look inflamed or infected
- wear a mask to protect yourself from airborne contanimation
buccal swab
- collected from inside of the cheek in the mouth
- collects pt DNA
- gently rub swab against inside of pts cheek
what should you verify on the requisition form when receiving a forensic specimen
- type of specimen
- case number
- name, age, and sex of person it was taken from
what color tube is used to test testosterone levels
red
where to collect two sets of blood cultures from
- if both must be taken from the same site: wait 1 hr
- draw from two separate sites to get most accurate results: two sites on pt left arm
