Hematology and Coagulation
Jennifer Jeffries, CLS, MLS (ASCP) (PM Shift Supervisor)
Routing Hematology Testing
- Complete Blood Count-No differential: Includes WBC, RBC, Hgb, HCT, MCV, MCH, MCHC, Plts and RDW.
- Complete Blood Count with Automated Differential: Includes all of the above plus a five-part differential. Cells identified are Granulocytes (includes Polys and Bands), Lymphocytes, Monocytes, Eosinophils, and Basophils.
- Manual Differential: Includes WBC differentiation, RBC morphology, and platelet estimation. This is not an orderable test. If the automated differential fails pre-set flagging criteria, a manual differential is then performed by the laboratory. It is charged at that time.
- Platelet Count: This test is a part of the blood count but may be ordered separately. On occasion, abnormalities of the sample may make it necessary to perform a manual, phase platelet count.
- Reticulocyte Count: Performed by flow cytometry method on the Coulter. If required STAT during off-hours, or when interferences exist in the sample, a manual count will be performed.
- Sedimentation Rate: Minimum volume for analysis is 1 mL EDTA blood.
- Microhematocrit: Minimum requirement for analysis is 2 heparinized microcapillary tubes for microcentrifugation.
- Body Fluid Analysis: Includes a manual red and white cell count and a differential based on a cytocentrifuge prepared smear. CSF specimens are performed STAT. Synovial fluid analysis may also includes Crystals.
NOTE: When specific cellular or marked abnormalities are noted on any of the above tests, review by a Pathologist is initiated and, when appropriate, an interpretive report is sent to the chart.
Special Hematology Testing
- Urine Eosinophil Count: Then performed by manual staining methods.
- Malaria Smears: Both thick and thin smears reviewed. Sent to Public Health for speciation.
- Kleihauer-Betke Stain: Screen for fetal bleed and numerate fetal cells if indicated.
- Hemoglobin Analysis (Electrophoresis): May include Electrophoresis by Isoelectric Focusing; Hemoglobin A2, Hemoglobin, Fetal, Quantitative, Fetal, Betke Kleihauer; Interpretation and blood count. Performed weekly, dayshift only.
Acceptable Specimens for Routine Hematology Testing
- EDTA Anticoagulated tuves must be at least half full.
- Peripheral blood specimens containing clots will be rejected.
- CSF specimens to be sent in sterile CSF tube.
- Synovial fluids and body fluids should be sent in sterile containers.
- All body fluid samples must be received in the Hematology Laboratory no later than 4 hours after collection.
- EDTA blood tubes are retained 24 hours after testing.
- Stained peripheral blood and fluid smears are retained for 4 weeks after testing.
Routine Coagulation Testing
- (PT) Prothrombin Time resulted as INR
- (aPTT) Activated Partial Thromboplastin Time
- Anti-Xa Unfractionated Heparin
- Anti-Xa Low Molecular Weight Heparin
- Fibrin Monomer
- FDP-Fibrin(ogen) Degradation Products
- Thrombin Time
- Inhibitor Screen (PT/PTT)
Special Coagulation Testing
Performed weekly unless noted. Available dayshift Monday-Friday only.
- Factor Assays: Performed daily, Monday through Friday, dayshift only. Available as STAT at other times with Pathologist's approval.
- Inhibitor Assay: Specify factor performed on Fridays
- Von Willebrand Activity: Performed on Wednesdays.
- Von Willebrand's Antigen: Performed on Wednesdays.
- Protein C Assay: Performed on Thursdays.
- Protein S Assay: Performed on Thursdays.
- Dilute Russel's Viper Venom Test (DRVVT): Performed Thursdays.
- Heparin Associated Antibody Test: Performed Monday through Friday day shift only
- Platelet Aggregation: Performed Tuesday by prearranged appointment only.
- ADAMTS13 testing; Performed on Wednesdays with Heme/Onc approval. STAT testing may be available but must be approved by Heme/Onc and Pathology.
Acceptable Specimens for Hemostasis Testing
One 5 mL blue-top tube with liquid (3.2% buffered acid citrate) is adequate for all of the above mentioned tests except:
Cryofibrinogen - 2.5 cc lavender (EDTA) top tube or red top maintained at 37?C And sent to the lab ASAP following collection.
Cryoglobulin - 7 cc red top maintained at 37?C.
Fibrin(ogen) Degradation Products - blue top tube with powder.
Call SARC at extension 4-0500 if any of the above tubes are needed.
Technique for Collection of Hemostasis Samples
Use a "two-syringe" technique whenever drawing any specimen for hemostasis testing, i.e., the first 3 mL from a venipuncture should be drawn into a separate tube or syringe and set aside; then, blood from the second tube or syringe can be used for the hemostasis sample. The sample should be put on ice immediately. Drawing a hemostasis sample from a heparin lock is not advised due to the risk of heparin contamination. The ratio of blood:anticoagulant is very critical. Patients with hematocrits less than 20% or greater than 60% require a special tube available from the laboratory. Please call 4-0500 to request these tubes. All tubes drawn for coagulation work must be full.
Incompletely filled tubes and specimens received more than four (4) hours after collection will be rejected.