Phlebotomy Study Guide for the Medical Assistant test

Processing

For specimen processing, be familiar with how to operate equipment, such as a centrifuge. Know how to divide samples into aliquots, if needed. Appropriate storage is also needed and this may include refrigeration. In non-evacuated tubes, know the manufacturer’s recommendations for fill ratios.

Labeling

Lab specimens should be always labeled with patient identifiers such as name and birthdate. The type of specimen, date, time, and initials of collector should also be on the label. If specimens are received without this information, another sample will be needed. Be sure to always check with your facility to verify what additional label information might be required.

Additives

Additives for tubes include clot activators, anticoagulants, and thixotropic gels. The type of additive depends on the lab test ordered. Review which additive is appropriate for each lab tube and lab test.

Handling

When handling or transporting lab specimens, be aware of any special considerations, such as sensitivity to light or temperatures. When handling evacuated tubes with additives, tubes should be inverted after collection. Be sure that all equipment is in safe working condition and is not expired. If equipment is expired or not functioning properly, alert your manager, and be sure to appropriately label the equipment so it is not used by staff.

Testing

Review normal and abnormal lab values. Be familiar with each lab test, and how results are reported. Report any critical abnormal values.

Hematology Panel

A hematology panel includes hemoglobin, hematocrit, ESR, cell counts and INR.

Hematocrit

Hematocrit is a measurement of the volume of red blood cells to whole blood. A normal hematocrit ranges from 37-47% in adult females and 40-54% in adult males.

Hemoglobin

Hemoglobin is a measurement of the oxygen-carrying capacity of a red blood cell. Normal hemoglobin is 12-16 for a woman and 14-18 for a man.

Erythrocyte Sedimentation Rate

An ESR is a measurement of the time it takes for red blood cells to settle at the bottom of a test tube. Results are read one hour after sample collection.

Automated Cell Counts

An automated cell count includes red blood cell count, white blood cell count, and platelet count. Review normal values for these labs.

Coagulation Testing/INR

A PT/INR is a test used to monitor blood coagulation. It is frequently used to monitor patients on blood thinning medications.

Chemistry/Metabolic Testing

Chemistry testing includes glucose testing, BUN/creatinine (kidney function), liver function, cholesterol (lipid profile), and Hemoglobin A1C.

Glucose

Glucose testing can be done using capillary puncture. A lancet is used on the finger, and the blood sample is read using a reagent strip.

Kidney Function

Blood urea nitrogen (BUN) and creatinine are tests used to monitor kidney function. High levels of these indicate kidney dysfunction.

Liver Function

Liver function tests include ALT and AST. In the case of liver inflammation, these levels are elevated. A test called a GGT can also be used to monitor for elevated bilirubin.

Lipid Profile

HDL, LDL, and total cholesterol are included in a lipid profile.

Hemoglobin A1c

Hemoglobin A1C is another type of glucose testing that is an estimate of average blood sugar over a 3-month time frame.