Flashcards in 53 & 54 Hematology & Blood Draw Deck (99):
Plasma could be retrieved from
Thixotropic gel can be found in some tubes, including Becton-Dickinson’s SST tube with the red-gray marbled top and PST tube with the green-gray marbled top. The density of this synthetic gel is between that of red cells and plasma or serum, and it settles between the two during centrifugation, forming a barrier. This barrier facilitates retrieval of the liquid portion without cellular contamination.
The needle size most commonly used in infants and older adults is _____ gauge
The smallest gauge needles (23-gauge) are used to collect blood from small or fragile veins, such as those of older or very young patients.
The color of the tube top for the collection of a coagulation test is
Light blue tops contain sodium citrate, which prevents blood from clotting.
Leaving a tourniquet tied on a patient’s arm for longer than the recommended time results in
Hemoconcentration can occur, which is an increased concentration of blood cells in proportion to plasma.
No anticoagulants are found in which of the following tubes?
Red-topped tubes have no additives and are used for serology and chemistry studies.
Which is the most correct method for performing a capillary puncture?
Squeezing the finger causes an increase in tissue fluids, the lateral surface of the finger should be used, alcohol should be allowed to dry before the sample is collected, and the first drop of blood is wiped away because it contains tissue fluid.
The needle size most commonly used for adult venipuncture is ___ gauge.
Routine adult venipuncture requires a 20- to 21-gauge needle.
Which vein(s) can be used for routine venipuncture?
The medial veins generally run parallel or at a slight angle to the fold in the antecubital area, whereas the cephalic veins run lateral or to the outside of the antecubital area. These veins are the veins of choice.
The slant at the open end of a needle used for venipuncture is called the:
The bevel is the slanted edge at the tip of the needle.
During a routine venipuncture, when should the phlebotomist request that the patient make a fist?
After the tourniquet is in place, the patient should be asked to make a fist; the medical assistant then palpates for an acceptable vein with the ungloved index finger.
The device used for dermal puncture is a(n):
A lancet is used to perform a dermal puncture; it delivers a quick puncture to a predetermined depth.
A needlestick is more likely to occur if:
The medical assistant should never attempt to recap a contaminated needle.
Which type of tube should be used to collect blood specimens during a glucose tolerance test?
The fluoride in gray-topped tubes prevents glycolysis.
The clear part of whole blood that contains clotting agents is
Plasma is the liquid part of whole blood that provides the medium for blood cells and dissolved particles to be carried through the bloodstream.
A hematoma can be caused by
The most common causes of hematoma formation during blood draws are excessive probing with the needle to locate a vein, failure to insert the needle far enough into the vein, and penetration of the needle through the vein. *All of the above
You are performing a capillary puncture on a patient and are having difficulty collecting an adequate sample. Which of the following is an accepted method to encourage blood flow from the site
Gentle massage of the finger encourages blood flow without risking the quality of the sample.
The most common phlebotomy site in adults is (are) the
The medial and cephalic veins in the antecubital space are the veins of choice for phlebotomy in an adult patient.
_________ is an anticoagulant that prevents platelets from clumping and preserves the appearance of blood cells for microscopic preparation
Ethylenediamine tetraacetic acid (EDTA), which is present in the lavender-topped tube, prevents platelet clumping and preserves the appearance of blood cells for microscopic examination
Which is the proper technique for performing a venipuncture?
The needle bevel should always be face up so that the sharpest part of the needle is inserted first; the needle is inserted at a small angle so that it does not pass through the vein.
When is the correct time to remove the tourniquet during a routine venipuncture?
As the end of the draw nears and the last tube to be collected fills, the tourniquet should be carefully released.
A tourniquet should remain tied on a patient’s arm no longer than:
1 minute. Leaving a tourniquet on for longer than 1 minute greatly increases the possibility of hemoconcentration and altered test results.
Without a clot activator, whole blood typically clots in ________ minutes.
30 to 60. Clot activators promote clotting of blood. Without a clot activator, blood clots in 30 to 60 minutes, after which it must be centrifuged.
You are required to collect a venous sample for a typical hematology test, the complete blood count. You collect:
The EDTA in the lavender-topped tube prevents platelet clumping and preserves the appearance of blood cells for microscopic examination.
Why should a tourniquet not be tied too tightly?
The tourniquet should not be tied so tightly as to impede arterial blood flow; this restricts venous blood return, resulting in poor venous distention.
*All of the above
In a routine venipuncture, the angle at which the needle enters the arm should be _______ degrees.
15 Degrees. The needle should enter the arm at a 15-degree angle, parallel to the vein, to puncture the vein without passing through it.
Thixotropic gel, found in the SST red-gray marbled-topped Vacutainer tube is:
less dense than red blood cells but more dense than serum. Thixotropic gel can be found in some tubes, including Becton-Dickinson’s SST tube with the red-gray marbled top and PST tube with the green-gray marbled top. The density of this synthetic gel is between that of red cells and plasma or serum, and it settles between the two during centrifugation, forming a barrier.
Before a routine venipuncture or capillary puncture, the site typically is cleaned with:
The most commonly used antiseptic is 70% isopropyl alcohol.
During a routine venipuncture, when should the phlebotomist request that the patient release the fist?
When blood enters the first tube or barrel, the patient should be asked to unclench her or his fist.
A syringe is preferred over a Vacutainer collection device when:
Syringes are used when there is concern that the strong vacuum in a stoppered tube may collapse the vein.
The ____________ is the part of the venipuncture needle that fits into the syringe or Vacutainer adapter.
The hub attaches the needle to the adapter or syringe.
A winged infusion set is also known as a:
Butterfly needles are designed for use on small veins, such as those in the hand or in pediatric patients.
Blood obtained via capillary puncture can be collected:
in Microtainer tubes.
in capillary tubes.
in microhematocrit tubes.
onto filter paper.
by *all of the above.
Capillary blood samples may be collected at all of the following sites except the:
The antecubital space is used to collect venous samples.
The needle size most commonly used by the blood bank for donations is ___ gauge.
16; Blood bank donation requires a larger gauge needle; using a 16-gauge needle to collect blood reduces the chance of hemolysis.
A tourniquet is used during the phlebotomy procedure to:
A tourniquet prevents venous flow out of the site, causing the veins to bulge.
*Both B and C
The proper procedure for collecting a serum specimen is to:
A serum specimen must clot, and red-topped and marble-topped tubes aid this process.
*Both B and D
The laboratory requisition indicates that you are to collect a venous blood specimen for hematology testing, serum chemistry testing, and coagulation studies. What is the proper order of collection for these tubes?
The order of tube filling is light blue, red, and lavender to secure the blood samples.
Which of the following Vacutainer tubes is routinely used for hematology testing?
Lavender-topped tubes contain EDTA to prevent clotting; therefore, samples for hematology testing are collected in these tubes.
Which of the following tests is used to determine renal function?
Creatinine levels increase if the kidneys are damaged and cannot excrete waste adequately.
Which component of the complete blood count is not necessary to calculate the red cell indices?
The differential analyzes the numbers of WBCs in the blood sample.
Thrombocytes are not true cells but rather cytoplasmic fragments of a large cell in the bone marrow, the megakaryocyte. The coagulation of the blood is initiated by blood platelets. Thrombocytopenia is a decrease in normal platelets.
*none of the presented answers
Which of the following is not detected in a liver panel test?
CBC. A liver panel is ordered to detect possible damage in hepatocytes. If damaged, these cells release certain enzymes, including gamma-glutamyltransferase (GGT), ALT, and alkaline phosphatase (ALP). A CBC count provides information about all blood cells but not about blood enzymes.
act as phagocytes. The granular leukocytes, called polymorphonuclear leukocytes, include the neutrophils, eosinophils, and basophils. They are characterized by their heavily granulated cytoplasm and segmented nuclei. Granular leukocytes are phagocytic and engulf invading bacteria and viruses. Unlike erythrocytes, leukocytes function in the tissues.
Which department of the laboratory performs H&H tests?
The hematology section deals with the counting of RBCs, WBCs, and platelets, differentiating WBCs on stained blood smears, measuring the percentage of RBCs in blood (hematocrit), and determining the oxygen-carrying capacity of the blood (hemoglobin).
Hormones detected in a thyroid panel include:
All three hormone levels are assessed in a thyroid panel. The pituitary gland produces TSH to stimulate the thyroid to produce T3 and T4.
*All of the above
When performing a microhematocrit:
Capillary tubes should be filled two-thirds to three-quarters full and sealed with clay before they are placed in the centrifuge.
The ESR test results:
vary greatly between genders and as people age.
The ESR test result is not specific for a particular disease, but is used as a general indicator of inflammation. Normal values vary slightly with age and gender. Various tests can be done, and some are CLIA-waived. The results are reported in millimeters per hour (mm/hr).
When is the administration of Rho(D) immune globulin absolutely necessary?
If an Rh-negative mother gives birth to an Rh-positive stillborn. Rho(D) immune globulin is a protein solution containing large amounts of Rh(D) antibodies. It is given to the Rh-negative mother by injection after a miscarriage or abortion or after the delivery of an Rh-positive baby. In most cases, it now is also given during pregnancy. The immune globulin prevents the infant’s Rh-positive cells from stimulating the mother’s immune system.
Hemoglobin A1c is measured to monitor:
Diabetes. The hemoglobin A1c (HbA1c) test provides information about the average blood sugar level during the previous 2 or 3 months. In the blood, glucose binds irreversibly to hemoglobin molecules in RBCs. The amount of glucose bound to hemoglobin is directly tied to the concentration of glucose in the blood.
Which of the following is a normal adult WBC count?
10,000 cells/mm3 The normal WBC count varies with age. It is higher in newborns and declines throughout life. The average adult range is 4,000 to 11,000 cells/mm3.
The copper sulfate method of determining the hemoglobin level is:
The copper sulfate method is a CLIA-waived, manual method of determining the hemoglobin level. It is often used to screen blood donors. The test is based on the principle of specific gravity. When a drop of blood from a patient with a normal hemoglobin value is dropped into a copper sulfate solution, it falls rapidly to the bottom. If the drop falls slowly or not at all, the hemoglobin level is below reference range.
*All of the above
A properly prepared wedge smear:
A good wedge smear should cover one half to three fourths of the slide. It should show a gradual transition from a thick to a thin end, with a feathered edge. It should have a smooth appearance with no ridges, holes, lines, streaks, or clumps. The cells should be distributed evenly on microscopic examination.
While Mr. Chakrabarti’s hematocrit sample is spinning in the centrifuge, you perform an automated hemoglobin test on a sample of his blood and record the value as 15 g/dL. You do a quick mental calculation and expect that the hematocrit value will be approximately:
45%. Hemoglobin and hematocrit are often performed together and are referred to as an “H&H.” A quick mental calculation should always be done before reporting out H&H results; the hemoglobin value, ´3 ±3, should equal the hematocrit value.
Which statement is true about HDL?
It transports cholesterol. HDL cholesterol is known as the good cholesterol because a high level of HDL cholesterol seems to protect against heart attacks. Medical experts think that HDL carries cholesterol away from the arteries and back to the liver, where it is passed from the body.
The protime is:
The protime, or prothrombin time (PT), test uses whole blood collected in a tube that prevents the blood from clotting. This test, which measures how well the blood clots, is used to monitor patients taking warfarin.
*All of the above
A hematocrit reading of 37 indicates what?
RBCs account for 37% of the total blood volume. The hematocrit is a measurement of the percentage of packed RBCs in a blood sample.
A decreased hematocrit value could be the result of:
A low microhematocrit value can indicate anemia or the presence of bleeding; a high value may be caused by dehydration or a condition such as polycythemia vera.
*both B and C
Dr. Lim orders a creatine phosphokinase (CPK) draw on Mr. Roberts. What do elevated CPK levels indicate?
Possible myocardial infarction (MI). CPK levels are elevated if tissue damage has occurred; myocardial damage causes an increase in CPK.
The buffy coat:
Is white. After centrifugation, RBCs are at the bottom of the tube, the white buffy coat, which includes WBCs and platelets, is in the center, and the plasma is on top.
Which statement is true about leukocytes?
Leukocytes are the largest circulating blood cells.
Granulocytes have segmented nuclei.
Neutrophils are the most numerous WBCs in circulation.
Bacterial infections stimulate increased production of neutrophils.
*All of the above.
Leukocytes are the largest of the normal circulating blood cells. Each of the five types has a characteristic appearance. The granulocytes include neutrophils, eosinophils, and basophils. Granulocytes contain distinctive granules in their cytoplasm and may have segmented nuclei. The agranulocytes include lymphocytes and monocytes. They have few, if any, granules and nonsegmented nuclei. The nuclei of the leukocytes should appear purple, and their cytoplasm may vary from pink to blue or blue-gray. Neutrophils are known by a variety of names, including polymorphonuclear neutrophils and segmented neutrophils (“polys” and “segs”). They are the most numerous WBCs in circulation in adults. They are produced in bone marrow, released into the circulation, and eventually enter tissues to fight off invading microorganisms by phagocytosis. Many types of bacterial infections stimulate increased production of neutrophils.
A blood test that analyzes the ability of the kidneys to perform their function is the:
BUN. The blood urea nitrogen (BUN) test evaluates the kidneys’ ability to filter out and excrete wastes.
Which of the following is a normal H&H for a woman?
36% and 14 g/dL. The normal range for the hematocrit in women is 36% to 45%; the normal range for the hemoglobin is 12 to 16 g/dL.
Thyroid-stimulating hormone (TSH) levels are assessed to determine the function of which organ(s)?
The pituitary gland produces TSH to stimulate the thyroid to produce triiodothyronine (T3) and thyroxine (T4).
Which of the following is an abnormal value for a differential?
50% to 70% basophils Basophils are associated with an immediate immune response to external antigens, such as occurs with asthma, hay fever, and anaphylaxis.
A person with type O blood has:
anti-A and anti-B antibodies in circulation. Type O negative blood is referred to as the universal donor because it has no circulating antibodies to the ABO antigen, nor does it have Rh antigens that might sensitize an Rh-negative recipient.
Erythrocytes have a typical ________ shape because of _________.
convex; adequate hemoglobin concentration
The immature form of the RBC has a nucleus that disintegrates as the cell matures. Loss of the nucleus results in the familiar shape of the RBC, the biconcave disk that is thicker at the rim than in the middle.
Increases in the RBC count are found in which of the following disorders?
Dehydration. The RBC count often is decreased in anemia. Increases are found in individuals with dehydration, polycythemia vera, or severe burns and in people who live at high altitudes as an adaptation to the lower oxygen content of the air.
You need to collect a venous blood specimen from a patient to run an FBS. Which of the following would be an inappropriate statement to make to the patient during this procedure?
“This procedure will not hurt.”
Which of the following antecubital veins is considered the best vein to use for a venipuncture?
Median cubital vein
Which of the following represents an ERROR in technique when obtaining a capillary blood specimen?
Using the first drop of blood for the test
If you suspect a vein selected for venipuncture might collapse, you should:
Use the butterfly method to perform the venipuncture
Which of the following is a disadvantage of using the syringe method of venipuncture?
The amount of blood specimen that can be collected is limited by the size of the syringe
Which of the following gauge needles should be used to perform a venipuncture?
An evacuated glass tube with a red stopper contains:
What may occur if an outdated evacuated tube is used to collect the blood specimen?
The tube may no longer have a vacuum Correct
During the venipuncture procedure, a sudden swelling occurs in the area around the puncture site. You should:
Immediately remove the tourniquet and then the needle
When performing a capillary puncture, the finger should NOT be squeezed to avoid:
Diluting the blood sample with tissue fluid Correct
Which of the following sites can be used to make a skin puncture on an adult?
Lateral part of the third fingertip
Which of the following should NOT be used as a venipuncture site?
An area that is painful to the patient
*All of the above
The primary function of a neutrophil is to:
Engulf pathogens through phagocytosis Correct
Which is the largest of the white blood cells?
Leukocytes do their work in the:
An increase in eosinophils often occurs:
During an allergic reaction Correct
Mrs. Nelson has a white blood cell count of 14,500. This is considered:
Above normal range Correct
Which type of the following white blood cells has granules in the cytoplasm that stain a bright reddish orange?
Mr. Johnson has a hematocrit reading of 60. This is considered:
The nucleus of a neutrophil generally contains:
Three to five lobes
Mr. Peterson has a hemoglobin reading of 16. This is considered:
Within normal range Correct
Pus consists of all of the following EXCEPT:
Hemolysis of a blood specimen results in:
Inaccurate test results Correct
On standing, a blood specimen to which an anticoagulant has been added separates into:
Plasma, buffy coat, and blood cells Correct
When performing a venipuncture, which of the following techniques represents a violation of the OSHA standard?
Placing the contaminated needle in a biohazard bag
Which of the following represents an ERROR in technique when selecting a vein for venipuncture?
Using the thumb to palpate the vein
Which of the following indicates the correct order of draw for the vacuum tube method of venipuncture?
Red, green, lavender, gray
You are performing a venipuncture, and the patient becomes dizzy and is about to faint. Your first priority in this situation should be to:
Protect the patient from injury
Which of the following may result in hemolysis of the blood specimen?
Using a needle with a small lumen to collect the specimen
Why should the veins of the hands be used as a venipuncture site only as a last resort?
They have a tendency to roll
They are more difficult to stick
The procedure is more uncomfortable for the patient
The hand veins are more susceptible to collapsing
*All of the above
An evacuated glass tube with a lavender stopper contains: