Patient Preparation & Specimen Collection PDF

Summary

This document provides guidelines for patient preparation and specimen collection procedures in a clinical laboratory setting. It covers considerations for safety, proper labeling, and handling of specimens, as well as different types of specimens and their preparation. It also details specific instructions for handling various types of specimens.

Full Transcript

LEARNING ACTIVITY 1 PATIENT PREPARATION, SPECIMEN COLLECTION, LABELLING, & PROCESSING Specific Learning Objectives: At the end of this activity, the learner will be able to: 1. provide proper information to patient; 2. collect biological...

LEARNING ACTIVITY 1 PATIENT PREPARATION, SPECIMEN COLLECTION, LABELLING, & PROCESSING Specific Learning Objectives: At the end of this activity, the learner will be able to: 1. provide proper information to patient; 2. collect biological specimens properly and safely; 3. handle bilogical specimens properly and safely; and 4. process biological specimens properly and safely Introduction to Specimen Collection Laboratory tests contribute vital information about a patient's health. Correct diagnostic and therapeutic decisions rely, in part, on the accuracy of test results. Adequate patient preparation, specimen collection, and specimen handling are essential prerequisites for accurate test results. The accuracy of test results is dependent on the integrity of specimens. Safety and Disposal Considerations in Specimen Collection In all settings in which specimens are collected and prepared for testing, laboratory and health care personnel should follow current recommended sterile techniques, including precautions regarding the use of needles and other sterile equipment. Treat all biological material as material that is potentially hazardous as well as contaminated specimen collection supplies. For all those who are involved in specimen collection and preparation, the responsibility to adhere to current recommendations designed to maintain the safety of both patients and health care workers does not end when the patient is dismissed. There are four steps involved in obtaining a good quality specimen for testing: (1) preparation of the patient, (2) collection of the specimen, (3) processing the specimen, and (4) storing and/or transporting the specimen. Since information related to any of these areas may change as clinical laboratory technology changes, please refer to the latest edition of the Labcorp Directory of Services and Interpretive Guide for current instructions. Preparation Prior to each collection, review the appropriate test description, including the specimen type indicated, the volume, the procedure, the collection materials, patient preparation, and storage and handling instructions. Preparing the Patient. Provide the patient, in advance, with appropriate collection instructions and information on fasting, diet, and medication restrictions when indicated for the specific test. Preparing the Specimen. Verify the patient's identification. Proper identification of specimens is extremely important. All primary specimen containers must be labeled with at least two identifiers at the time of collection. Submitted slides may be labeled with a single identifier, but two identifiers are preferred. Examples of acceptable identifiers include (but are not limited to): patient's name (patient's first and last name exactly as they appear on the test request form), date of birth, hospital number, test request form number, accession number, or unique random number. A location such as a hospital room number is not an appropriate patient identifier. If chain of custody documentation is necessary for the procedure, follow the appropriate protocol. All specimens should be labeled in the presence of the patient. Process and store the specimen(s) as required. Appropriate storage and handling are necessary to maintain the integrity of the specimen and, consequently, the test results. General Specimen Collection. Some of the common considerations affecting all types of specimens:  Please examine specimen collection and transportation supplies to be sure they do not include expired containers. · Label a specimen correctly and provide all pertinent information required on the test request form. Submit a quantity of specimen sufficient to perform the test and avoid a QNS (quantity not sufficient), as indicated in the test requirements. (See Quantity Not Sufficient.) · Use the container/tube indicated in the test requirements for appropriate specimen preservation. · Follow patient instructions prior to specimen collection Including the proper order of blood draw when multiple tubes are required. · Carefully tighten specimen container lids to avoid leakage and/or potential contamination of specimens. · Maintain and transport the specimen at the temperature indicated in the test requirements. · Mix specimen with additive immediately after collection by inverting 5-10 times. Serum Preparation. The most common serum preparation considerations:  Separate serum from red cells within two hours of venipuncture.  Mix by inverting specimen with additive immediately after collection.  Allow specimens collected in a clot tube (eg, red-top or gel-barrier tube) to clot before centrifugation.  Avoid hemolysis: red blood cells broken down and components spilled into serum. Causes and prevention are discussed under the section on hemolysis.  Avoid lipemia: cloudy or milky serum sometimes due to the patient's diet (discussed under the section on lipemia). Plasma Preparation. The most common considerations in the preparation of plasma:  Collect specimen in additive indicated in the test requirements.  Mix specimen with additive immediately after collection by inverting 5-10 times.  Avoid hemolysis or red blood cell breakdown.  Fill the tube completely, thereby avoiding a dilution factor excessive for total specimen volume (QNS).  Separate plasma from cells within two hours of venipuncture or as indicated in the test requirements.  Label transport tubes as “plasma”  Indicate type of anticoagulant (eg, “EDTA,” “citrate,” etc) Collection Procedures Collection of Vacuum Tubes Containing Additives (eg, anticoagulants, preservatives, clot activators, gel-barrier). When using vacuum tubes containing an additive: 1. Tap the tube gently at a point just below the top to release any additive adhering to the tube or top. 2. Permit the tube to fill completely to ensure the proper ratio of blood to additive. There will be some dead space at the top of the tube. 3. To allow for adequate mixing of blood with the anticoagulant or preservative, use a slow rolling wrist motion to invert the tube gently four to eight times. Failure to invert tubes may lead to the formation of microscopic clots. 4. Rapid wrist motion or vigorous shaking may contribute to hemolysis. 5. Check to see that all the preservative or anticoagulant is dissolved. If any preservative powder is visible, continue inverting the tube slowly until the powder is dissolved. 6. If multiple samples are being drawn, invert each specimen as soon as it is drawn. Do not delay. Place the tube upright in a rack as quickly as possible after collection. 7. The gel-barrier tube is an additive tube and should be inverted five to six times after collection. Allow the tube to stand for 30 to 60 minutes for complete clotting to occur prior to centrifugation. Collection of Vacuum Tubes Without Anticoagulants. When using vacuum tubes containing no additives: 1. Permit the tube to fill completely. 2. Let the specimen stand for 30 to 60 minutes and (preferably) not longer than 60 minutes prior to centrifugation. 3. Centrifuge the specimen at the end of the waiting period in accordance with the manufacturer's instructions for speed. Hemolysis In general, grossly or even moderately hemolyzed blood specimens may not be acceptable for testing. Hemolysis occurs when the red cells rupture and hemoglobin and other intracellular components spill into the serum. Hemolyzed serum or plasma is pink or red, rather than the normal clear straw or pale yellow color. Most cases of hemolysis can be avoided by observing the steps listed. 1. For routine collections, use a 21- to 22-gauge needle. (On occasion, however, it may be necessary to use a 23-gauge needle for patients from elderly and pediatric populations with small or difficult veins.) 2. If there is air leakage around the needle or loss of vacuum in the tube, replace the vacuum tube. 3. If you are using your own collection equipment instead of the vacuum tube technique, use only clean, dry, sterile needles, syringes, and tubes. 4. Collect blood in room temperature containers unless the specimen requirement specifies otherwise. 5. When there is difficulty accessing a vein or when a vacuum tube fills too slowly due to a difficult venipuncture, damage to the red blood cells may result. Address this problem by collecting a fresh tube when blood flow is established or select another puncture site and, using sterile/unused equipment, collect a second specimen. Also, use of a blood pressure cuff, in lieu of a tourniquet, will reduce trauma to fragile red blood cells. 6. Do not remove the needle from the vein with the vacuum tube engaged. This applies to both the last tube collected during a routine venipuncture and to tubes collected during a difficult procedure. 7. Premature removal of the tube causes a rush of air to enter the tube, which may result in damage to the red cells. 8. Be as gentle as possible, drawing the blood evenly. Too much pressure in drawing blood into a syringe or forcefully ejecting blood into a collection tube from a syringe may damage red cells. 9. Allow collection site to dry after cleaning with the alcohol pad. Alcohol used to clean the puncture site may cause contamination in a tube. 10. Do not collect a specimen from or through a hematoma. 11. Allow specimen to clot completely (for 30 to 60 minutes) before centrifuging. 12. Do not centrifuge the specimen for more than 10 minutes unless otherwise specified by the collection instructions. Lipemic Serum or Plasma (Turbidity) Normal serum or plasma is a clear and light yellow to straw in color. Turbid serum or plasma appears cloudy or milky. Serum or plasma may be cloudy due to bacterial contamination or chronic or transient high lipid levels in the patient's blood. The primary dietary sources of lipids (fatty substances) are meats, butter, cream, and cheese. Patients who consume these foods within the 24-hour period immediately preceding collection of a blood specimen may have temporarily elevated lipid levels, which may be manifested by cloudy or lipemic serum. Lipemic serum or plasma may not be a true indicator of the patient's physiologic state. Regardless of diet and length of fast, some patients may produce cloudy specimens. To avoid dietary-induced high lipid levels prior to testing, many physicians require patients to exclude the high-fat foods from their diets or to fast for 12 to 14 hours prior to specimen collection. For morning specimen collection, the laboratory recommends that the patient be required to fast from 6 PM on the previous evening. Quantity Not Sufficient One of the most common problems in specimen collection is the submission of an insufficient volume of specimen for testing. The laboratory sends out a report marked QNS (quantity not sufficient), and the patient has to be called back for a repeat collection at an inconvenience to the patient and to the physician. To ensure an adequate specimen volume: 1. Always draw whole blood in an amount 2½ times the required volume of serum required for a particular test. 2. For example, if 2 mL serum are required, draw at least 5 mL whole blood. If there is difficulty in performing venipuncture, minimum volume may be submitted if it is indicated in the test description. For most profile testing, draw at least two 8.5-mL gel-barrier tubes. 3. If pediatric tubes are used, be sure to collect an adequate volume of specimen to perform the test. 4. Provide patients with adequate containers and instructions for 24-hour urine and stool collections. 5. It is critical, especially for any specimen collection tube containing an additive, to allow the tube to fill to the "fill line" marked on the tube. This requirement is important in order to achieve the proper blood-to-additive ratio; otherwise, the specimen may be found to be QNS. Specimen Storage and Shipping Temperatures The definition of specimen temperatures for storage and shipping is as listed below: Room Temperature: 10.1 – 40.0 oC Refrigerated: 1.0 to 10.0 oC Frozen: -1.0 to -80.0 oC Preparing the Patient Patient Instructions It is important to gain the patient's understanding and cooperation in obtaining an acceptable specimen. Patient States Basal State. In general, specimens for determining the concentration of body constituents should be collected when the patient is in a basal state (ie, in the early morning after awakening and about 12 to 14 hours after the last ingestion of food). Reference intervals are most frequently based on specimens from this collection period. The composition of blood is altered after meals by nutrients being absorbed into the bloodstream. Consequently, postprandial blood (blood drawn after a meal) is not suitable for some chemistry tests. An overnight fast is preferable (from 6 PM of the evening previous to collection) to ensure that the patient is in the basal state. This minimizes the effects of ingested substances on the test results. Before you collecthe specimen, ask the patient when he/she last ate or drank anything. If the patient has eaten recently and the physician wants the test to be performed anyway, you should indicate “nonfasting” on the test request form. In the clinical information/comments section of the test request form, indicate the time the patient ate. Fasting does not include abstaining from coffee, tea, or sugar-free liquids. Fasting or diet restrictions, such as low-fat diets, should be explained in detail, particularly to aged or overanxious patients or their caregivers. Inform patients that fasting does not include abstaining from water. Dehydration resulting from water abstinence can alter test results. When specimens are not collected in the basal state, the following additional effects should be considered when interpreting test results.  Exercise. Moderate exercise can cause an increase in blood glucose, lactic acid, serum proteins, and creatine kinase (CK).  Emotional or Physical Stress. The clinical status of the patient can cause variations in test results.  Time of Day of Collection. Diurnal variations and variations in circadian rhythm can also affect test results. For example, growth hormone peaks in the morning before waking and decreases throughout the day. Serum iron levels may change as much as 30% to 50%, depending on individual variation, from morning until evening. Note: For chemistry profiles, 12- to 14-hour fasting specimens are recommended. Timed Specimens There are two types of timed blood specimens: One is for a single blood specimen ordered to be drawn at a specific time. The other is for a test that may require multiple blood specimens to be collected at several specific times. Single Specimens. Here are some instances in which timed single specimens may be required.  Fasting plasma glucose alone or in conjunction with a random glucose determination, as recommended by the American Diabetes Association, to diagnose diabetes. Fasting here is defined as no caloric intake for at least eight hours.  Postprandial glucose may be performed two hours after a meal for a timed test that is helpful in diabetes detection.  Blood glucose determinations may be ordered at a specific time to check the effect of insulin treatment.  Blood cultures may be ordered for a specific time if a bloodstream bacterial infection is suspected.  Therapeutic monitoring of patients on medication. Multiple Specimens. Here are some instances in which timed multiple specimen tests may be ordered  The most common timed procedure is a glucose tolerance test. First, a blood specimen is drawn from a fasting patient. Then, the patient is given glucose orally and blood specimens are drawn at fixed intervals. (See following illustration.) Note: The American Diabetes Association and the World Health Organization (WHO) have specific recommendations for glucose tolerance testing.  The tolbutamide (Orinase®) test is similar to a glucose tolerance test, but the collection intervals vary.  To test the effect of a certain medication, a physician may order the same test to be obtained on consecutive days, before, during, and after the patient has received a medication. Sequential Sampling Diagnosis of many endocrine diseases requires sequential sampling of blood and/or urine. 1. All sequential specimens are from the same patient and are sent to the laboratory at the same time. 2. The specimens are clearly labeled with their chronological sequence (1 of 6, 2 of 6, time of drawn or Fasting, ½ hr, 1hr, etc) and with the patient's name, other unique identifier, and date of collection. 3. Only one test request form accompanies the serial samples, and it is completed with all patient information, including any medications administered and the number of samples sent. 4. The test request form and all specimens are sent in one container (box or plastic specimen transport bag). Serial Monitoring Monitoring a patient over time for a specific condition is a variation of sequential sampling. Many tumor markers (tests used to follow the patient's response to treatment for cancer) may be monitored over the course of several years. Specific instructions for serial monitoring are found in the test description for the applicable test being monitored. Interference of Medications and Other Substances Many common prescription and nonprescription (over-the-counter) medications can interfere with chemical determinations or alter levels of substances measured. Drug interference is complicated and often method-dependent such that only general recommendations can be stated here. Precautions to be observed must be determined by the physician, and the patient must then be told to avoid specified medications for the necessary periods of time prior to specimen collection. If the patient cannot be taken off the medication in question, its presence should be noted on the test request form. Summary: Interference of Medications and Other Substances 1. Drugs or their metabolites are frequently concentrated in the urine in sufficient amounts to interfere significantly with urine assays. (See appendices or individual tests for specific information.) 2. Drug interference of notable clinical significance has been well- documented in the following instances. 1. Thiazide diuretic therapy. The pharmacologic or toxic effect is hyperuricemia and hyperglycemia. 2. Catecholamine assay. If a “24-hour drug abstinence period” for a patient is not possible, order VMA or metanephrines. 3. Oral contraceptives cause a decrease in serum vitamin B12 levels that is often indistinguishable from vitamin B12 deficiency of any cause. They also cause an increase in total serum thyroxine- binding globulin. This results in increase in both total serum thyroxine and unsaturated thyroxine-binding globulin, but with no significant change in unbound (free) thyroxine. 3. Many medications have been shown to have long-term residual effects that interfere with testing. (Biotin is one example of this that is often administered in high dosages.) Blood Collection / Transport Containers Anticoagulants and Preservatives. To ensure accurate test results, 1. All tubes containing an anticoagulant or preservative must be allowed to fill completely. 2. Attempts to force more blood into the tube by exerting pressure, as in collection with a syringe, will result in damage to the red cells (hemolysis). 3. If the vacuum tube is not filling properly, and you are certain that you have entered the vein properly, substitute another tube. 4. Occasionally, vacuum tubes lose their vacuum. If the specimen cannot be properly collected, select another site and using new, sterile collection equipment, collect the specimen. 5. (Special note for light blue [sodium citrate] tubes used for coagulation studies: Always fully seat and hold the tube securely on the Vacutainer® hub while filling.) Note: Use plastic transport tubes for all frozen specimens. Specimen Containers.Red-top tube: Contains no anticoagulant or preservative. Use: Serum or clotted whole blood. Serum must be separated from cells within 45 minutes to two hours depending on the test(s). Mottled red/gray-top, gold-top, or cherry red-top (gel-barrier) tube: Contains clot activator and gel for separating serum from cells, but not anticoagulant. Do not use gel-barrier tubes to submit specimens for therapeutic drug monitoring. Always check the test description to determine whether a gel-barrier tube is acceptable. Use: Serum, may be used for assays requiring serum unless otherwise stated. Separate serum from cells within 45 minutes to two hours depending on the test(s). Serum may be sent in the centrifuge tube with an intact barrier (correct separation upon centrifugation) between cells and serum or in a plastic transport tube. If specimen is centrifuged before clotting is complete, a fibrin clot will form on top of the cell. This finding is frequent in hemolyzed specimens. Also, the gel barrier may not be intact and could cause improper separation of serum and cells, possibly affecting test results. Lavender-top tube: Contains K2 EDTA. Use: EDTA whole blood or plasma. Send plasma in a plastic transport tube labeled “Plasma, EDTA.” Send whole blood in a lavender-top tube. Gray-top tube: Contains sodium fluoride (a preservative) and potassium oxalate (an anticoagulant). Use: Sodium fluoride whole blood or plasma. Send plasma in a plastic transport tube labeled “Plasma, Sodium Fluoride.” Send whole blood in a gray-top tube. Blue-top tube (also light blue-top tube): Contains sodium citrate. Be sure to use only tubes with a 3.2% sodium citrate concentration. These are easily identified by the yellow diagonal stripes on the label. Use: Sodium citrate plasma. Send plasma in a plastic transport tube labeled “Plasma, Sodium Citrate.” Send whole blood in a blue-top tube. Green-top tube: Contains sodium heparin or lithium heparin. Use: Heparinized whole blood or plasma. Send plasma in a plastic transport tube labeled “Plasma, Sodium Heparin” or “Plasma, Lithium Heparin.” Send whole blood in a green-top tube. Yellow-top tube: Contains acid citrate dextrose (ACD) solution. Use: ACD whole blood. Send whole blood in a yellow-top tube. Royal blue-top tube: Contains sodium EDTA for trace metal studies. Some royal blue-top tubes do not contain EDTA. Use: EDTA whole blood or plasma. Send whole blood in a royal blue-top tube. Send plasma in a plastic transport tube labeled “Plasma, EDTA from royal blue.” Tan-top tube: Contains sodium EDTA for blood lead analysis. Use: EDTA whole blood. Send whole blood in a tan-top tube. Plasma Preparation Tube (PPT™): Contains EDTA. Use: EDTA plasma for molecular diagnostic tests (eg, polymerase chain reaction (PCR) and/or branched DNA amplification (bDNA) techniques). Upon centrifugation, a gel barrier is formed between the plasma and the cellular components of the blood. The tube can be sent directly to the lab without transferring to a secondary tube. Plastic tubes can be frozen at -80°C without risk of breakage. Assembling Supplies. Assemble the following supplies: lab coat, gloves, labels, safety needle, needle holder, tourniquet, appropriate tubes, gauze, alcohol sponge, adhesive strip, and sharps container. Put on the lab coat and gloves. The aseptic method of collecting and transporting a blood specimen works on the principle of a vacuum tube for drawing blood. A double-pointed needle or multiple sample needle (both disposable) may be used for venipuncture. Ordinarily, a 21- or 22-gauge needle is used. A small bore, sharp needle causes minimum patient discomfort; 22- or 23-gauge is the smallest bore (or lumen) size recommended to avoid hemolysis. A needle length of 1 to 1½ inches permits an angle of entry that will not pierce both vein walls and enter tissue. When more than one blood specimen is required, multiple sample needles and vacuum tubes make blood collection simpler and more efficient. A tiny rubber sleeve automatically closes when the vacuum tube is removed from the holder, preventing leakage and loss of blood when the tubes are being changed. Place the sharps container within reach. Open the single or multiple sample needle package in front of the patient; do not tear the paper seal for the needle's cap, and do not remove the needle's cap (sterile shield) at this point. Preparation of the needle and syringe 1. Prepare the needle holder in order to attach the safety needle in the appropriate manner. 2. Pull the safety shield on the needle back over the holder before removing the needle shield. Thread the needle into the holder and tighten it firmly. 3. With some needle assemblies, you may slide the collection tube into the holder, carefully pushing the tubes forward until the needle touches the stopper. 4. Gently tap tubes containing additives to dislodge any material that may be adhering to the stopper. 4. Carefully push the tube forward until the top edge of the stopper meets the guideline on the holder. Let go. The tube will retract below the guideline. Leave it in that position. This step embeds the full point of the needle in the stopper without puncturing it, preventing blood leakage on venipuncture and the premature loss of vacuum. During venipuncture, do not have the patient clench and unclench the fist repeatedly (“pumping”). This will cause a shift in fluid between the vein and the surrounding tissue. This can lead to changes in concentration of certain analytes. To facilitate making the vein more prominent, the patient may be asked to hold firmly to a rubber ball, a thick wad of gauze, etc. Also, never leave a tourniquet on the arm for more than one minute without releasing it. This can cause discomfort to the patient and may also cause hemolysis. Preparing the Puncture Site. After securing the tourniquet and reaffirming your selection of the best vein, both by sight and palpation, proceed as follows. Note: If a patient has intravenous (IV) solutions going into one or both arms, it is acceptable to puncture the vein 3 to 4 inches below the site of the IV. 1. Except when a blood alcohol is ordered, swab the site with a sterile alcohol sponge (70% alcohol) in a circular motion, inside to outside, to push contaminants away from the puncture site. Do not routinely use an iodine preparation. Iodine may contaminate specimens for certain chemistry tests. 2. Allow the puncture site to air dry after swabbing, or dry the site with gauze. If alcohol is not allowed to dry, it may cause specimen hemolysis. If the arm is dry, you will avoid stinging the patient at venipuncture. 3. Break the paper seal on the needle cap in the presence of that patient, and remove the needle cap. Visually inspect the point of the needle for burrs and possible discoloration along the shaft of the needle before using the needle. If it has burrs or discoloration, do not use that needle; use another sterile needle. 4. Anchor the vein. Enter the vein with the needle at an angle of approximately 15 to 30 degrees. Considerations for Single and Multiple Sample Collection. If only a single collection tube is required, when the vacuum is exhausted and the tube completely filled, release the tourniquet, and remove the tube from the needle assembly. Place a piece of dry gauze over the needle and withdraw the needle carefully. When multiple specimens are required, remove the first collection tube from the holder as soon as blood flow ceases, invert the first tube to prevent clotting, and gently insert the second tube into the holder. Puncture the diaphragm of the stopper by pushing the tube forward and initiating vacuum suction. Remove and invert each successive tube after it is filled. When all samples have been drawn, remove the entire assembly from the arm. Firmly lock the safety shield on the needle; confirm that it has locked both visually and audibly. Dispose of the used needle and holder in a sharps container according to the provisions in your exposure control plan. Do not recap, cut, or bend any needles; dispose of them in a sharps container. Do not reuse needles. 1. Apply direct pressure to the puncture site. After drawing blood, observe proper venipuncture techniques to prevent continued bleeding and/or hematoma. Excessive bleeding (longer than five minutes) should be brought to the attention of the physician. Also, a clot tube (eg, red-top tube or gel-barrier) that does not clot should be brought to the attention of the physician. Note: When multiple specimens are drawn from a single venipuncture, the following order is recommended: (1) sterile blood culture tubes, (2) nonadditive clotting tubes (red), (3) coagulation tubes and tubes containing citrate (blue), (4) gel-barrier tubes and tubes with additives (red), (5) tubes containing heparin (green), (6) tubes containing EDTA (lavender, royal blue), (7) tubes containing acid citrate dextrose (yellow), and (8) tubes containing sodium fluoride and potassium oxalate (gray). Note: If the blood has to be mixed with an additive (gently invert the tube 4 to 10 times depending on the specimen tube being used), this must be done immediately after collection. You can do this quickly while the patient's arm is elevated. Mix blood with anticoagulant thoroughly, using a rolling wrist motion and by inverting the tube gently 4 or 10 times. As soon as possible after collection, set the blood upright in a test tube rack. 1. Label tubes in front of the patient immediately after collection, confirming all necessary information with the patient. 2. If blood is drawn for routine hematology, prepare the blood films (blood smears) immediately after collection. 3. Complete the test request form to indicate time and date of collection along with collector's identification. Syringe Transfer Technique in Venipuncture A syringe is usually used with patients who are difficult to collect by routine venipuncture procedure, including techniques using a safety-winged blood collection set (butterfly). With the syringe technique, venipuncture is accomplished without direct connection to the collection tube. Follow these steps: 1. Use disposable plastic syringes and safety straight needles or a safety- winged blood collection set. For most laboratory specimens, using 20 mL plastic syringes will allow the withdrawal of adequate specimen. Generally, the needle should not be smaller than 21-gauge. 2. If glass syringes are used, it is essential that the barrel and plunger be absolutely dry. Small amounts of moisture can cause hemolysis. If the glass syringe has been autoclaved, it should be oven dried before use. Air drying techniques are usually not satisfactory. 3. After the blood is collected by syringe, activate the safety feature of the safety straight needle or safety winged blood collection set. Dispose of the used needle in a sharps container according to the provisions of your exposure control plan, and fill the vacuum tubes according to the provisions of your exposure control plan. Use blood transfer device to fill tubes from syringe. 4. Do not force blood into the tube by pushing the plunger; this can cause hemolysis and may disrupt the ratio of specimen to anticoagulant. Blood Specimen Preparation Procedures There are two important guidelines to follow when submitting blood specimens. For some tests, such as chemistry procedures, fasting samples are often the specimen of choice. Also, because hemolysis interferes with many procedures, please submit samples that are as free from hemolysis as possible. References 1. Bishop, M., Clinical Chemistry 9th ed.,2023 2. Rodriguez, Ma. Theresa T., Review Handbook in Clinical Chemistry, 2023 3. Harr, Robert R., Medical Laboratory Science Review, F.A. Davis, 2020 4. Mcpherson Richard A. and Matthew R. Pincus. Henry’s Clinical Diagnosis and Management by Laboratory Methods 23rdt ed. Philadelphia: Elsevier Inc., 2017 5. Turgeon, Mary Louise, Linne & Ringsrud’s Clinical Laboratory Science: Concepts, Procedures, and Clinical Applications, Elsevier Mosby, 2020 6. https://www.labcorp.com/resource/blood-specimens-chemistry-and- hematology Students’ Activity : Return Demonstration RUBRICS FOR RETURN DEMONSTRATION RETURN DEMONSTRATION (total = 20pts) CRITERI LEVELS OF ACHIEVEMENT A EXCELLENT (4) GOOD (3) NEEDS UNACCEP- SCORE IMPROVEMENT TABLE (1) (2) PREPAR The studentwas The studentwas The student had The student is ED- NESS able tofollow able to compose done the every not prepared, theprocedure oneself step of the there is guidelines given whiledoing procedure inaccuracy, withgreat theevery step of guidelines but incompleteness, the procedure showing a little no consistency, accuracy,complete guidelines with unpreparedness and exceed at ness,confidence,an accuracy,complet while doing the the time allotted dconsistency within eness, steps. to finish the the time allotted to confidence, and whole course. finish the whole consistency within procedure the time allotted to finish the whole procedure COMPLE The studentwas The student was The student was The student was TENESS able to performed able toperform able to perform the able to perform entirety the totally the procedure the procedure procedure procedure guidelines with lot guidelines with guidelines correctly guidelines with a of shortcomings lot of from 1s tstep up to little inaccuracy in and inadequacy in incompleteness the last step. 1s tstep up to the doing the 1st step and absence of last step. up to the last step some steps. CONSIST The student is very The student is The student is The student is ENCY sophisticated,the competent; the partly competent; not yet student is student is less the student is not competent, the observant, observant,accurat so observant, student entertain accurate,focus and e, focus and accurate, focusand more more harmonize harmonizes while harmonizes while distractions and while doing the doing the different doing the different showed different steps of the steps of the immaturity and procedure procedural less focus. https://www.coursehero.com/file/130832458/RUBRICS-FOR-RETURN-DEMONSTRATION-VIDEO- PRESENTATION-1docx/

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