LABORATORY WORKFLOW AND LABORATORY SAFETY Flashcards
THREE PHASES OF TESTING PROCESS
Pre analysis
Analysis
Post analysis
Pre analysis
Activities that take place before testing
Test ordering and sample collection
Analysis
Activities that produce a result
Running a sample on an automated analyzer
Post-analysis
Patient reporting and result interpretation
PRE-ANALYSIS
_______of all testing errors occur in this phase
32-75%
Why is pre analysis the most critical phase?
Errors in this phase create rework or additional investigations that may cause unnecesary procedures and costs to the patients and to the healthcare system
FACTORS OF PRE-ANALYSIS
Pre-collection variables
Specimen collection
Specimen transport
Specimen processing
PRE-COLLECTION VARIABLES
Posture
Age
Gender
Exercise
Diet
Time variations
Stress
One of the most frequent errors:
selecting the wrong lab test
Test order
May be _____ or _____
_______may be made during emergency situations and should be documented given that…
electronic or in writing
Verbal requests; Official lab requests must be placed after the blood is drawn
what are add-ons
Additional tests requested on a specimen previously collected
Problems of “add-ons”
specimen is not the proper type, residual volume is insufficient, storage conditions result in analyte deterioration
There should be lab policies on the following
• If a patient refuses to have blood drawn
• If the patient was unable to be drawn
• If the patient is unavailable
• If the patient is combative
• If the patient becomes ill or faint
SPECIMEN COLLECTION
Time of Collection
Difference of ASAP and STAT collection
ASAP: do it whenever you are already free “ yes, this is important, but don’t drop EVERYTHING to do it now”
STAT: stop whatever you are doing now and collect the sample
Time of Collection
Timed specimens: OD, TID, BID, Qn (e.g. Q12, Q8, Q6, Q4, Q1)
OD:
TID:
BID:
Qn-
Once a day
Ter in die - thrice a day every
Bis in die - twice a day
Hour interval
Trough specimens:
Definition and what time of collection
reflect the lowest level in the blood; drawn 30 minutes before the drug is administered
Troughs of medication concentration occur after the drug has been broken down and metabolized by the body.
Peak vs Trough specimen
A peak is the highest level of a medication in the blood, while a trough level indicates the lowest concentration.
When are Peak specimens drawn?
shortly after medication is given
Low trough levels indicate…
fast drug clearance
Peak specimens…
reflect the highest level of drugs in the blood
Peak specimen
• Intravenous:
• Intramuscular:
• Oral:
15-30 minutes after injection/infusion
30 minutes- 1 hour after injection
1 hour after drug is ingested
• Excessively high peak levels could lead to…
toxicity and/or side effects
REASONS FOR SPECIMEN REJECTION
• Hemolysis/lipemia
• Clots present in an anticoagulated specimen
• Non-fasting specimen when test requires fasting
• Improper blood collection tube
• Short draws, wrong volume
• Improper transport conditions (e.g., no ice for blood gases)
• Discrepancies between requisition and specimen label
• Unlabeled or mislabeled specimen
• Contaminated specimen/leaking container