Hematology Laboratory Safety Quiz

Hematology Laboratory - Patient Safety

• The National Patient Safety Goals include using patient identifiers, proper collection tubes, proper disinfection of lab countertops, and proper donning of gloves.
• The primary purpose of the laboratory safety manual is to protect patients and laboratory personnel, comply with local health and state regulations, and comply with OSHA regulations.
• If a blood specimen is spilled, the first step in cleanup is to wear gloves and a lab coat, absorb the blood with disposable towels, then clean with a 1% chlorine solution, and finally wash with water.
• The likelihood of infection after exposure to infected blood or body fluids depends least on the presence of nonintact skin, the concentration of the virus, or the duration of contact. The greatest risk factor is the source (anatomical site) of the blood or fluid.

Standard Precautions

• Standard precautions have been instituted in clinical laboratories to prevent healthcare workers from exposures to bloodborne pathogens such as HIV and HBV.
• Exposure to blood, sputum, urine, and semen constitutes the major source of HIV and HBV infection in healthcare personnel

Dilution of Bleach

• Diluted bleach should be freshly prepared by mixing a 1:10 dilution of household bleach with water (10 mL bleach in 100 mL H₂O).

Verbal Reports

• Verbal reports are permissible in situations when a patient is going directly to the physician's office and would like the report, or if the report cannot be found at the nurse's station

Quality Assessment

• The most frequent type of laboratory specimen error is preanalytical, analytical, or postanalytical.
• The delta check is used to detect whether the correct anticoagulant was used, the time of specimen storage, discrepancies between current and past results, and the correct collection time.
• Instrument calibration must be performed, at least, annually according to CLIA.

Accuracy and Precision

• Accuracy refers to closeness to the true value, while precision refers to how close test results are when repeated.
• Calibration is the process of monitoring accuracy and reproducibility of known control results.

Quality Control

• A control specimen is a known value in a specimen similar to a patient specimen, closeness to the true value, or the process of monitoring accuracy.

Additional Information

• Minimum number of samples for control reference range validation is 30.
• Acceptable limits for a control value must fall within ±2 standard deviations of the mean.
• A trend change in QC is a progressive change in one direction away from the mean for at least 3 days.
• A standard deviation is the difference between upper and lower measurements in a series of results, expressed as the average degree to which test data vary about the average.
• Variance is a measurement of how much the test data varies about its average.

Blood Samples and Collection Methods

• Different anticoagulants are used for different types of tests.
• The correct color-coded stopper for EDTA anticoagulant is lavender, heparin is blue, and sodium citrate is green.
• The appropriate veins for venipuncture are the cephalic, basilic, and median cubital veins.
• The bevel of the needle should be held upward during venipuncture.
• Acceptable skin puncture areas for capillary blood collection from infants include the medial or lateral plantar surface, posterior curve of the heel, or arch.
• The proper collection of capillary blood includes wiping away the first drop, occasionally wiping the site, and avoiding the introduction of air bubbles into the column.

Blood Smear Preparation

• The properly prepared peripheral blood smear begins with a delay in preparation after collection, with a normal drop size and angle during preparation.
• For peripheral blood smears if too long, decreasing the angle or using a larger drop of blood will help.

Bone Marrow Examination

• Bone marrow examination helps in diagnosing bleeding disorders, erythrocyte disorders, leukocyte disorders, and acute leukemias.
• Appropriate bone marrow aspiration sites are the anterior and posterior iliac crests, and the sternum.

Stains

• Basic staining effects imparts a color to specific cells. Different stains are used to color blood cells differently.
• Differentiating acidic stains and neutrophil stains are based on the color of the stain used.

Additional Hematology Information

• General characteristics for maturation and development of erythrocytes include nuclear chromatin condensation in reticulocytes, a bluish tinge in Wright-stained reticulocytes, and megaloblastic maturation or the presence of abnormal ribosomal elements.
• The typical characteristics for mature monocytic cells are a large, round nucleus, light gray cytoplasm, and a kidney-bean-shaped nucleus. A mature monocytes is larger than a mature lymphocyte, characterized by a kidney-bean-shaped nucleus, and a light-gray cytoplasm.
• Typical characteristics of mature neutrophils include a segmented nucleus, light sky-blue cytoplasm, and an elongated/curved (or irregular) shaped nucleus.
• A mature eosinophil is typically characterized by large orange granules, an elongated/curved (or irregular) shaped nucleus and light-gray cytoplasm. A mature lymphocyte is larger than a mature neutrophil, has a kidney-shaped nucleus and light-gray cytoplasm.
• Methods to identify variations in erythrocyte size variations include macrocytosis, microcytosis, or anisocytosis, or variations in shape (e.g. spherocytosis.
• Disorders associated with anemia include iron-deficiency anemia or pernicious anemia, or other abnormalities associated with defective erythropoietin.
• The functions of platelets include maintaining vascular integrity, promoting fibrinolysis, or the formation of a platelet plug or promotion of fibrinolysis.
• Causes of abnormal platelet counts can be due to inherited disorders.

Other Notes

• Common types of anemia include iron deficiency, pernicious, megaloblastic, or hemolytic.
• Methods to assess reticulocytes, cell counts, or hemoglobin levels are available for laboratory testing.
• Abnormal conditions in the bone marrow can result from extramedullary hematopoiesis. -Anemia, or deficient erythropoiesis or hematocrit, results in the body's cells not getting enough oxygen.
• Important laboratory parameters for testing blood include MCV, MCH, MCHC, RDW, total WBC count, or reticulocyte count.
• Important blood disorders to monitor include anemia, leukocytosis, polycythemia, or thrombocytopenia.
• A normal range for reticulocytes in adults is 0.5–1.0% .
• A normal range for PCV is 36–45%.
• A normal range for total WBC count is 4.0–10.0 x 10⁶/L (or 4.5-11.0 × 10^9/L).
• A normal range for lymphocytes in adults is approximately 20% to 45%.
• If a patient has a high or low count of neutrophils or lymphocytes, this may be indicative of an infection, or other medical conditions.