Pre-Analytical
An unconscious patient in the ER has no ID band. How do you label the specimen?
Use emergency temporary ID protocols (e.g., Trauma number/name) matching the ER tracking sheet and nurse validation before leaving.
You need to dilute concentrated hydrochloric acid with water. What is the golden rule?
Always add acid to water (never water to acid) to prevent exothermic splattering.
The ESR (Erythrocyte Sedimentation Rate) tube is left slanted on the rack instead of strictly vertical. Impact?
Falsely accelerated/elevated sedimentation reading.
A serum sample for a basic metabolic panel sits unspun on the bench for 4 hours at room temperature. Effect on glucose?
Falsely decreased glucose levels due to ongoing cellular glycolysis.
Gram-positive cocci appear under the microscope as purple clusters after staining. Suspected organism?
Staphylococcus species.
You finish a difficult draw and realize you used a light blue tube before a light green tube. Is this an order of draw error?
Yes. Sodium citrate (blue) must never follow a tube with additives;
Personal protective equipment (PPE) must be removed in what order to prevent self-contamination?
Gloves first, then face shield/goggles, lab coat/gown, and mask last (followed by thorough hand hygiene).
A patient with severe hemolytic anemia shows polychromasia on the blood smear. What are these cells?
Young, anucleated red blood cells (reticulocytes released prematurely).
A green-top (PST) tube is received for a baseline lithium level. Can you run it?
No,avoid lithium heparin if testing for baseline lithium levels.
A urine sample is positive for nitrites and leukocyte esterase. Indicates?
Urinary tract infection (UTI).
A newborn heel stick sample for bilirubin is exposed to direct bright fluorescent room light. What is the impact?
Falsely decreased bilirubin due to photo-oxidation; the tube must be wrapped in foil/amber shield immediately.
An electrical analyzer sparks and smokes. First action before touching it?
Turn off the main electrical power supply / pull the plug if safe to do so.
What is the primary function of EDTA in a hematology tube?
Chelates calcium ions to prevent blood clotting while preserving cellular morphology
What chemistry enzyme is most specific to acute myocardial infarction damage compared to skeletal muscle?
Cardiac Troponin (cTnI or cTnT); historically CK-MB was used.
A Stool specimen for ova and parasites (O&P) is refrigerated immediately upon arrival. Acceptable?
Stool for O&P should not be refrigerated as it harms motility/morphology; fixatives must be used at room temp.
Blood flow stops abruptly halfway into filling a second lavender tube. You adjust the needle slightly, but nothing happens. Cause?
Collapsed vein or the bevel is resting against the vein wall; gently reposition or release the tube and let a vacuum re-establish.
An autoclave cycle finishes, but the indicator tape stripes did not change color. Status of load?
Unsterilized/Invalid; the load must be re-autoclaved
A peripheral smear shows marked Rouleaux formation (red blood cells looking like a stack of coins). Associated condition?
Elevated immunoglobulins/plasma proteins, often associated with multiple myeloma or acute inflammation
An ammonia test must be handled in what specific manner after collection?
Drawn on ice, spun immediately in a refrigerated centrifuge, and analyzed instantly or frozen.
A blood bank specimen lacks the mandatory second signature/witness verification of patient identification. Action?
Reject immediately; transfusion safety guidelines require strict dual-person positive identification validation
You receive a gray-top tube for a lactic acid test that was left at room temperature for 2 hours. Acceptable?
No. Lactic acid must be placed on ice immediately and analyzed quickly to prevent cellular glycolysis inflation.
You find a blood culture bottle with an unknown barcode on the counter with no paperwork. Action?
Discard safely as unidentifiable hazardous waste; untraceable clinical samples cannot be processed.
An automated analyzer flags a "Lymphocytosis" with atypical variants. What is the mandatory next step?
Make a manual blood smear, stain with Wright-Giemsa, and perform a manual differential count.
Troponin I levels are requested on a chest pain patient in the ER. What is the designated specimen type?
Heparin plasma or serum
A urine specimen contains WBC casts. Suggests?
Upper urinary tract infection