Laboratory Techniques and Procedures Flashcards

Which of the following is a transfusion science test?

Answer: DAT

The Direct Antiglobulin Test (DAT) is a crucial test in transfusion science, used to detect antibodies or complement components bound to red blood cells in vivo. It is vital for diagnosing conditions such as hemolytic disease of the newborn, autoimmune hemolytic anemia, and transfusion reactions. The other options listed are typically associated with chemistry or hematology, not directly transfusion science.

Which of the following items is NOT found in cryoprecipitate?

Answer: Factor V

Cryoprecipitate is a concentrated plasma derivative rich in specific clotting factors that precipitate out when fresh frozen plasma is thawed at cold temperatures. It primarily contains Factor I (fibrinogen), Factor VIII, Factor XIII, and von Willebrand factor. Factor V, however, remains in the cryoprecipitate-poor plasma and is therefore not found in significant amounts in cryoprecipitate.

A fecal sample for culture and sensitivity is collected:

Answer: by aseptic technique.

A fecal sample for culture and sensitivity must be collected using aseptic technique. This involves employing procedures to prevent contamination of the sample from external sources, ensuring that only the microorganisms present in the stool are cultured. While stool is not sterile, aseptic collection minimizes the introduction of environmental contaminants that could interfere with accurate diagnostic results.

What is the function of the gel separator in an evacuated blood collection tube?

Answer: RBCS and WBCS from plasma and serum

The gel separator in an evacuated blood collection tube forms a stable physical barrier between the cellular components (red blood cells and white blood cells) and the liquid portion (plasma or serum) after centrifugation. This separation prevents metabolic activity of the cells from altering analyte concentrations in the plasma or serum. It ensures sample integrity and allows for accurate testing of various analytes.

The laboratory rejects a specimen for INR testing because the specimen is in an evacuated tube with a light blue top and the specimen is:

Answer: delayed in transit for 6 hours.

A specimen for INR testing, collected in a light blue top tube with sodium citrate, is typically rejected if there's a significant delay in transit, such as 6 hours. Coagulation factors are labile and can degrade over time, leading to inaccurate results if not processed or tested within recommended timeframes. Prolonged delays compromise the integrity of the coagulation factors, making the test unreliable.

A physician in the ER performs a lumbar puncture on a patient. Which of the following tests are likely to be ordered?

Answer: Glucose, protein, Gram's stain, cell count

When a physician performs a lumbar puncture to collect cerebrospinal fluid (CSF), the primary tests ordered are typically for diagnosing infections, inflammation, or other neurological conditions. Therefore, a cell count (to check for increased white blood cells), glucose and protein levels (to assess for infection or inflammation), and a Gram's stain (to identify bacterial pathogens) are standard and crucial analyses performed on CSF.

An electrocardiogram is accurately described as a test that:

Answer: Records the activity of the heart

An electrocardiogram (ECG or EKG) is a non-invasive diagnostic test that measures and records the electrical activity of the heart over a period of time. It detects the electrical impulses generated by the heart muscle as it depolarizes and repolarizes during each heartbeat. This recording helps diagnose various heart conditions, including arrhythmias, myocardial ischemia, and infarction.