Module 6: Processing Flashcards
steps required for tests to be accurate
- correct specimen collection
- preparation for transport
- handling
- quality control
turnaround time
time it takes for the entire process including ordering, specimen collection, transportation, processing, analysis, and reporting
reference laboratory
- lab outside of the patient care facility
- perform more types of testing than those available at the average hospital lab
point of care (POC) tests
at or near the patient or at the patient’s bedside
steps of handling and transporting
- mixing the sample
- creating aliquots
- adding diluents
- centrifuging
- packaging the labeled specimen in a biohazard bag
- following thermal and light sensitivity procedures
aliquot
divide specimen into smaller portions
how to mix additives into blood sample
- gently invert as soon as possible after collection
- do not shake: hemolysis
- not mixing enough: formation of clots
thermolabile specimens
- sensitive to high temperatures
- use heat source or heat blocks to regulate temperature
- use ice slurries, refrigerators, or freezers for chilling purposes
- do not use cold or ice packs
- avoid fluctuating temperatures
photosensitive specimens
- abnormal reaction to or change resulting from exposure to light
- protect from light
special handling of ammonia
let blood tube sit in an ice slurry immediately after collection
special handling for lactic acid
let blood tube sit in an ice slurry immediately after collection
ice slurry
thick mix of water and ice
special handling for cold agglutinins
sample remains at body temp (37 C or 98.6 F)
special handling for bilirubin
wrap the blood tube in foil
special handling for vitamin A
amber bag
special handling for folate
wrap the blood tube in foil
special handling for blood gas tests
- store at room temperature for 15 to 30 minutes or in an ice slurry for up to 1 hr
- speedy delivery to prevent loss of gases from the blood prior to analysis
special handling for coagulation tests (other than PT)
- analysis takes place within 1 hr of collection
special handling for prothrombin time (PT)
- coagulation tests should be analyzed within 1 hr of collection
- a delay of up to 24 hrs at room temp will not affect the results (22 C or 71.6 F)
what specimens require centrifuging
specimens requiring separating the serum or plasma from the cells
two types of centrifuge rotors and what tests they are best for
- flat gel barrier: immunoassay and chemistry tests
- angled gel barrier: problematic for some chemistry tests
steps of centrifuging
- pre-centrifugation: handling and processing of specimens after collection and before centrifugation
- centrifugation: processing of specimens by spinning at high speeds in a centrifuge
- post-centrifugation: handling and processing of specimens once centrifugation process is complete and removal of serum or plasma is necessary
delay in separating plasma from cells should not exceed
2 hrs
what should a specimen with no anticoagulant added do before centrifugation
clot
how long does clotting take at room temperature
30 to 60 minutes
does chilling a specimen make clotting go faster or slower
slower
how is a blood sample separated when centrifuging
- heavy components (blood cells) move to the bottom
- lighter components (serum, plasma) move to the top
how do you know the speed and time to centrifuge a specimen
check manufacturers guidelines
affects of inadequate centrifugation
- portions of blood cells can remain in the plasma and serum
- incomplete formation of the barrier gel
how to place tubes in the centrifuge
- with stoppers and caps on
- balanced to prevent breaking
when is it best to remove serum or plasma from a blood sample
- immediately after centrifugation
- no longer than 2 hrs later
generally, how long should plasma and serum remain at room temp before testing
- no longer than 8 hrs
- otherwise, it needs refrigeration
- testing after 48 hrs requires freezing
when should you aliquot a specimen
right after completing the centrifugation process
how to aliquot a sample
- hold the empty tube adjacent to the specimen tube
- use a disposable pipette to transfer the serum (without cells) from the specimen tube to the aliquot tube
- label the specimen
how to package specimens
- in original specimen tubes or plastic screw-cap transfer tubes
- absorbent materials
- watertight primary containers
- watertight secondary containers (resealable bags, plastic canisters, foam boxes)
- strong outer packaging (fiberboard boxes or mailing tubes, wooden boxes, rigid plastic containers)
- coolants (ice packs, dry ice) if necessary
what should you do before placing a specimen in a biohazard bag
label the specimen with the pts full name, date and time of collection, and the source and type of specimen
timed blood tests
- glucose tolerance test
- 2 hr postprandial blood glucose level
- peak and trough values, often for antibiotics
how long after refrigeration should you process a urine specimen
1 hour
how to transport a urine specimen to a reference lab
- use evacuated tubes containing preservatives
- use disposable pipette or pour into tube
how long to keep urine at room temp for urinalysis with chemical reagent strip testing
no longer than 72 hours
how long to keep tubes at room temp for culture and sensitive tests
- up to 72 hours
- refrigerate if there is any delay
what should be completed on the lab requisition form for transportation to other sites for analysis
- pt name
- date
- type of test
- order provider’s name
- ICD-10-CM code for diagnosis
- provider signature
what tests can have altered results due to delays between collection and processing
- phosphorus
- glucose
- aldosterone
- calcitonin
- enzymes
hand delivery
- directly to reference lab
- use necessary carrying devices (trays, carts, tube racks, leakproof containers)
pneumatic tube systems
- usually in an inpatient setting
- efficient
- used to send and receive specimens, pt records, medications, and bills in a hospital
what tests are particularly affected by hemolysis
- potassium
- plasma hemoglobin
- lactate dehydrogenase
- acid phosphatase
- coagulation
automated carrier delivery
transport vehicle within facility
chain of custody
process that maintains control of and accountability for each specimen from the time of collection to the time of disposal
things required on the chain of custody form
- name of pt, body, subject, or object the specimen came from
- name of person who obtained and processed the specimen
- date, location, and signature of the person attesting that the specimen is the correct one and matches the documentation
- signature and date from every person who has possesion of the specimen for any amount of time
situations requiring the chain of custody process
- forensic analysis
- drug testing
- blood alcohol content testing
- occasionally: DNA analysis, rape test kits, parentage testing
forensic specimens
- rape, crime scenes, autopsies
- toxicology testing of substances after poisoning or substance abuse
- can be in any condition
Federal Drug Testing Custody and Control Form (CCF)
- for drug testing
- documents handling and storage information for specimens from the time they are obtained to their final disposal
what can urine drug tests usually detect
- marijuana use within the past week
- use of cocaine, heroin, an other illegal drugs within the past 2 days
- do not measure degree of impairment or frequency of use
types of drug testing
- workplace
- sports-related
- neonatal
workplace drug testing
- ensures compliance with federal regulations and company policy
- improves health an safety of employees
sports-related drug testing
- detects use of stimulants that enhance athletic performance
- analyzes blood and urine to detect blood doping (injections of blood cells to increase endurance) or use of erythropoietin (med for chemo pts, boost RBC production)
neonatal drug testing
- detects cocaine, opiates, amphetamines, methamphetamines, and phencyclidine which cause prenatal drug exposure and neonatal abstinence syndrome (withdrawal)
- specimen within 24 hours after birth to detect recent drug use
- specimen 24-72 hours after birth to confirm maternal drug use
most accurate method to identify alcohol level
blood specimen
what is lab information systems software used for
- transmitting test requisitions
- creating specimen labels, collection lists, and schedules
- monitoring and updating specimen records
- storing, reporting, and sending results
- submitting charges on pt account
- maintaining records of procedures, policies, and inventory
manual systems
require human interaction during pre-examination, examination, and post-examination steps in the testing process
semi-automated systems
parts of the testing process require little to no human input
automated systems
require human intervention only when errors occur
advantages of automated computer systems
- fewer clinical or documentation errors
- timely and accurate reports
- overall higher quality of patient care
information to input in semi-automated and automated methods of lab processing
- pt identification data (name, sex, date of birth)
- order provider’s info
- tests ordered
- date, time, and source of specimen collection
- special notes, other clinical data
- insurance or billing info
examples of informatics used in practice
- bar codes
- quick response (QR) codes
- radio frequency identification (RFID)
critical value
- test result that is significantly above or below the expected reference range
- could indicate a life-threatening situation
- requires an immediate response to the ordering provider
POC and CLIA waived tests that can be inserted into automated clinical analyzers for fast and accurate results
- electrolytes (sodium, potassium, chloride, calcium, magnesium)
- hematology (WBCs, RBCs, Hct, Hgb)
- glucose, hemoglobin A1c
- cholesterol (HDL, LDL, total cholesterol, triglycerides)
- blood coagulation (PT, INR)
rapid antigen detection test
identifies streptococcal pharyngitis
when to complete quality controls on a glucometer
- opening new package of test strips
- several tests have been significantly out of range
- changing batteries
what should you look at on a glucometer before testing every pt
compare the code on the glucometer with the code on the strips
how to provide results to clinical staff for POC testing
directly or by logging the data in the EHR
what information should you document when sharing verbal results
- pt name
- pt ID number
- name of the person receiving the report
- date and time
- detailed result information
- orgination of the report or results
most common and secure means for transmitting lab test results to providers
electronic reports
temperature for cryoglobulin specimen
37 C or 98.6 F
what info should be used to access a pts medical records
pt identification number
what symptom can low blood glucose cause
rapid heartbeat
example of information in the laboratory information system
previous lab results
does stat or asap have a higher priority
stat
what to do if you receive an unlabeled specimen
- recollect the specimen
- treated as a rejected specimen
tests required for reproductive testing on a female pt
FSH and LH
