SPECIMEN COLLECTION 1

Transcription

1 SPECIMEN COLLECTION 1

2 BLOOD 2

3 BLOOD SPECIMEN COLLECTION, PREPARATION AND HANDLING I. SPECIMEN COLLECTION A. Introduction As members of the health care team, phlebotomist must recognize that their primary responsibility is to the patient's health and well being. It is important for the phlebotomist to maintain a professional attitude and neat appearance. Good interpersonal skills help establish patient trust and alleviate apprehension. Specimen collection by venipuncture or skin puncture involves a series of steps that must receive careful consideration to ensure the best possible specimen for laboratory analysis. It is the responsibility of the phlebotomist to have a thorough understanding of and to abide by these guidelines to avoid the many potential sources of error. B. Preparation Prior to each collection, review the laboratory's specimen requirement. Note the proper specimen to be collected, the amount, the procedure, the collection materials, and the storage and handling requirements. Provide the patient in advance with appropriate collection instructions and information on fasting, diet, and medication restrictions when necessary. Confirm identification in the presence of the patient. Process and store the specimen as required. During specimen collection, preparation, and submission, there is a much greater possibility of critical error than during actual testing or examination of the specimen. Errors in storage and handling compromise the integrity of the specimen and, thus, the test results. Test results are only as good as the specimen collected. C. Patient Instructions and Preparation Procedures with needles induce stress and anxiety in many patients, and emotional stress can affect certain laboratory test values. The phlebotomist therefore should do his or her best to relieve such apprehension. Communicate with the patient in a calm, professional, and reassuring manner. Gain the patient's confidence by soliciting his or her cooperation. Reassure the patient that although the puncture itself maybe slightly painful, it will be over quickly. Never deceive the patient by saying the procedure will not hurt. 3

4 The patient should be comfortable with his or her arm easily accessible and fully extended. Patients in bed should be instructed to lie on their backs, if possible. The phlebotomist should seek assistance if patient movement is anticipated. If additional support is needed, a pillow may be placed under the elbow of the arm from which the specimen is to be drawn. Ambulatory patients should be seated comfortable in a chair, preferably one with an interlocking armrest for firm support. The phlebotomist should position himself or herself in front of the chair to protect the patient from falling forward if fainting occurs. The arm should be extended downward below shoulder level, and the opposite fist should be placed under the elbow for support. Please refer to the test directory section to note any specific dietary requirements or special restrictions for the ordered test. D. Blood Specimen Containers The accuracy of any specimen depends upon the quality of the specimen. Materials for proper specimen collection and transport are supplied by the Altoona Regional Health System Laboratory. Specimen Identification According to the National Committee for Clinical Laboratory Standards (NCCLS) H3-A4, Vol. ll. No.10, proper identification of specimens is extremely important. "All tubes should be labeled immediately after the blood specimen has been drawn. The completed label must be attached to each tube before leaving the side of the patient, and the identity of the person who drew the blood must be on the label". This procedure eliminates the possibility of mixing up the blood specimens. Unidentified samples will not be tested; therefore, clearly label each specimen with the patient's full name, date and time collected, test name and phlebotomist initials. Information on preprinted computer labels must be verified. Anticoagulants and Preservatives: To ensure accurate test results, all tubes containing an anticoagulant or preservative must be allowed to fill completely. Attempts to force more blood into the tube by exerting pressure will result in damage to the red cells (hemolysis). If the vacuum tube is not filling properly, and you are certain that you have entered the vein properly, substitute another tube. It is important to be certain that a tube is filled in order to avoid spurious results due to an inappropriate anticoagulant to specimen ratio. A partially filled collection tube may be acceptable. If a completely filled tube cannot be obtained, contact the lab to determine specimen acceptability before releasing the patient. 4

5 Vacuum Tubes Containing Anticoagulants: When using vacuum tubes containing anticoagulants and preservatives: 1. Tap the tube gently at a point just below the stopper to release any additive adhering to the tube or stopper 2. Permit the tube to fill completely to ensure the proper ratio of blood additive 3. To ensure adequate mixing of blood with anticoagulant or preservative, use a slow rolling wrist motion to invert the tube gently EIGHT times. Rapid wrist motion or vigorous shaking contributes either to small clot formation or hemolysis and fails to initiate proper mixing action 4. Check to see that all preservative or anticoagulant is dissolved. If any preservative is visible, continue inverting the tube slowly until the powder is dissolved. Vacuum Tubes Without Anticoagulants: When using vacuum tubes containing no anticoagulants or preservative: 1. Permit the tube to fill completely 2. Let the specimen stand for a minimum of 30 minutes and not longer than 45 minutes prior to centrifugation. This allows time for the clot to form. If the specimen is allowed to stand for longer than 45 minutes, chemical activity and degeneration of the cells within the tube will take place, and test results will be altered as a consequence. 3. Centrifuge the specimen at the end of the 30 to 45 minute period in strict accordance with the manufacturer's instructions for speed and duration of centrifugation. Note: Some tubes have clot activators and the clotting time may be less. Please check the package insert. 4. The Gold top tube (Hemogard closure) with clot activator is to be inverted (mixed) FIVE Times. THE ORDER OF DRAW According to the National Committee for Clinical Laboratory Standards (NCCLS) document H3-A4, "Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture," the order in which tubes should by filled is as follows: 1. Blood culture tube (yellow top or blood culture bottles) 2. Plain tube, non-additive (red top) without clot activator, must check tube 3. Coagulation tube (blue top) 4. Gel separator (speckled or tiger top) without clot activator, must check tube 5. Heparin tube (green top) 6. EDTA tube (lavender top) 7. Plain tube (gold top) gel separator with clot activator Because of the safety risks that accompany glass specimen tubes, infection control and epidemiology experts recommend the use of plastic tubes. 5

6 However, since plastic does not activate clotting, like glass does, red-top tubes must contain a clot activator if they are to be used for serum testing. As a result the order in which tubes are collected must take into consideration that plastic red tops, which contain clot activators, are tubes with an additive and should not occupy the same place in the order of draw as glass red tops without clot activators. The risk of drawing plastic red tops first in the order is that, during the tube exchange, the clot activator can carry over into the next tube. If the next tube is sodium citrate (blue top) for coagulation testing, the clot activator can alter the results. Therefore if using plastic tubes, the red top should be drawn after the blue top. If no blue top is drawn, the plastic red top can precede a heparin (green) or EDTA (lavender) tube without concern for carryover. The current thinking is that any carryover of the clot activator into tubes other than blue tops is irrelevant. It is thought that the minute amount of clot activator will be consumed by the excess heparin or EDTA and will not compromise their ability to anticoagulate the specimen. By contrast, carryover of a clot activator into sodium citrate (blue top) can consume clotting factors and result in prolonged clotting times even though the specimen will still be anticoagulated As a reminder, the NCCLS no longer recommends that a discard tube be drawn prior to a blue top if the blue top is being used for routine coagulation testing, i.e., protime or PTT. However, if factor assays are to be tested, a discard tube is recommended. Therefore, if a physician orders routine chemistries, coagulation studies, and a CBC, the order of draw if using a plastic red top is as follows: 1. Blue top 2. Red top 3. Lavender top If a glass red top is used, the order is: 1. Red top 2. Blue top 3. Lavender top Finally, heparinized tubes (green tops) should never be filled after an EDTA tube (lavender top) if the heparin tube will be tested for potassium. Because EDTA contains potassium salts, any carryover of EDTA into a heparin tube can result in falsely elevated levels of potassium. NCCLS bases the order of draw on well-researched evidence. Yet it remains phlebotomy's best-kept secret. By reinforcing the principles of sound blood collection practices through repetition and education, however, phlebotomists and their supervisors can minimize this frequently committed preanalytical error and maintain the specimen integrity that is essential to accurate results and quality care. 6

7 VACUTAINER INFORMATION Always purchase single use safety devices when performing phlebotomy procedures. YELLOW STOPPER Sterile collection of anticoagulated specimen used for microbiology studies (blood cultures) SPS(sodium polyanetholesulfonate) in 2.5 ml of sodium chloride for difficult venipunctures, pediatric or nursery patients. Use two for one set of blood cultures. Send whole blood in original tube BAC T/ALERT 40 ML STANDARD AEROBIC/F BLUE CAP This is a blood culture bottle. Draw the blue cap aerobic culture 1 st BAC T/ALERT 40 ML STANDARD ANAEROBIC/F PURPLE CAP This is a blood culture bottle. Draw the purple cap anaerobic culture 2 nd (1 SET EQUALS 1 BLUE CAP (AEROBIC) AND 1 PURPLE CAP (ANAEROBIC) RED STOPPER This is a tube that contains no anticoagulant or preservative. The clotted specimen will yield a serum sample. For Blood Bank tests, please submit in original tubes. All other tests, serum must be separated from cells within 45 minutes of venipuncture. Send serum in a plastic transfer tube. GOLD STOPPER TUBE OR MARBLED RED/GRAY Contains clot activator and gel for separating serum from cells, but no anticoagulant. The clotted specimen will yield a serum sample. Maybe used for assays requiring serum unless otherwise stated. Centrifuge tube to separate serum from cells within 45 minutes of venipuncture. Serum can be sent in original tube. BLUE STOPPER (LIGHT) Contains sodium citrate. Sodium citrate yields a plasma sample. Send plasma from a centrifuged sample in a plastic transfer tube labeled "Plasma, Sodium Citrate." If submitted immediately send whole blood in the original blue-stopper tube. GREEN STOPPER (MINT GREEN) Contains lithium heparin and a PST gel separator. Lithium heparin will yield a plasma sample. Plasma must be separated from the cells within 45 minutes of venipuncture. Centrifuge tube to separate the cells from the plasma and send in the original tube. 7

8 LAVENDER STOPPER (PURPLE TOP) Contains liquid K 3 EDTA. This anticoagulant yields plasma or whole blood. Send whole blood in the original lavender stopper tube and plasma in a plastic transfer tube labeled "Plasma, EDTA" GRAY STOPPER Contains Sodium Fluoride and Potassium Oxalate. These anticoagulants yield plasma or whole blood. Send plasma in a plastic transfer tube labeled "Plasma Sodium Fluoride". Send whole blood in the original gray stopper tube. ROYAL BLUE STOPPER TUBE May contain sodium heparin, Na 2 EDTA or no anticoagulant. Used for trace elements, toxicology and nutrient determinations. Send whole blood in the original royal blue stopper tube. BROWN STOPPER TUBES Contains EDTA (Na2). Send whole blood in the original brown stopper tube. 8

9 SELECTING APPROPRIATE COLLECTION TUBES Stopper Color Gold/Marbled Gray Gel Separator (SST) Light Green Gel Separator (PST) Tube Code GLD/ MR LGR Additive No anticoagulant Contains a clot activator and gel for separating serum from cells. Tube is to be gently inverted (mixed) 5 times immediately after collection Lithium heparin anticoagulant and gel for plasma separation. Tube is to be gently inverted (mixed) 8 times immediately after collection. Note: Sodium Heparin should not be used for Electrolyte determination. Red R No Additive No inversions (mixing) necessary. Clot activator Laboratory Use SERUM SST Brand Tube for serum determinations in chemistry. Tube inversions to ensure mixing of clot activator within 45 minutes of collection. Refrigerate Specimens-send in original tube Frozen Specimens-transfer serum to plastic container marked "Serum" NEVER FREEZE A SST TUBE HEPARINZED PLASMA PST Brand Tube for plasma determinations. Tube inversion to prevent clotting. Centrifuge within 45 minutes of collection. Refrigerate specimens - send in the original tube. Frozen Specimens - transfer plasma to a plastic transfer tube marked "Plasma Lithium Heparin". NEVER FREEZE A PST TUBE SERUM OR CLOTTED WHOLE BLOOD All other tests (serology/chemistry) centrifuge within 45 minutes of collection. Transfer serum to a plastic transfer tube marked "Serum". 9

10 SELECTION APROPRIATE BLOOD COLLECTION TUBE (CONTINUED) Stopper Color Tube Code Additive Lavender LV Liquid K 3 EDTA or Freeze-dried NA 2 EDTA Anticoagulant Tube is to be gently inverted (mixed) 8 times immediately after collection Light Blue LBL Sodium Citrate Anticoagulant Tube is to be gently inverted (mixed) 8 times immediately after collection. Yellow SPS SPS Sodium polyanetholesulfonate (STS) Anticoagulant Tube is to be gently inverted (mixed) 8 times immediately after collection Laboratory Use EDTA WHOLE BLOOD OR PLASMA For whole blood hematology determinations. Tube inversion prevents clotting. Send whole blood in original tube. For plasma specimen, centrifuge within 45 minutes of collection. Transfer plasma to a plastic tube marked "Plasma, EDTA" CITRATED PLASMA For coagulation determinations. Tube inversions prevent clotting. Send Whole blood in the original tube. For plasma specimen, centrifuge within 45 minutes of collection. Transfer plasma to plastic tube marked "Plasma, sodium citrate" NOTE: This tube must be completely filled to yield accurate results. Tubes not completely filled will be rejected. SPS WHOLE BLOOD OR BODY FLUID For blood culture specimen collections in microbiology. Tube inversions prevent clotting. Specimen should be submitted in original tube. Refer to microbiology specimen collection section for special collection guidelines. 10

11 SELECTING APPROPRIATE COLLECTION TUBES CONTINUED Stopper Color BAC T/ALERT Blue Cap Tube Additive Code BACT BAC T/ALERT Standard Aerobic 40 ml blood culture bottle. Laboratory Use AEROBIC BLOOD CULTURE BOTTLE WHOLE BLOOD Sterile collection required for Microbiology blood culture. Specimen should be submitted in original bottle. Refer to microbiology specimen collection section for special collection guidelines. 1 BLOOD CULTURE SET EQUALS 1 BLUE CAP (AEROBIC) AND 1 PURPLE CAP (ANAEROBIC ) BOTTLE. BAC T/ALERT Purple Cap BACT BAC T/ALERT Standard Anaerobic 40 ml blood culture bottle. Gray GRA Sodium Fluoride or Potassium Oxalate Tube is to be gently inverted (mixed) 8 times immediately after collection ANAEROBIC BLOOD CULTURE BOTTLE WHOLE BLOOD Sterile anaerobic collection required for Microbiology Blood Culture. Specimen should be submitted in original bottle. Refer to microbiology specimen collection section for special collection guidelines. 1 BLOOD CULTURE SET EQUALS 1 BLUE CAP (AEROBIC) AND 1 PURPLE CAP (ANAEROBIC) BOTTLE SODIUM FLUORIDE WHOLE BLOOD OR PLASMA Tube inversion to prevent clotting. Centrifuge within 45 minutes of collection. Send whole blood in original tube. 11

12 SELECTING APPROPRIATE COLLECTION TUBES CONTINUED Stopper Color Tube Code Additive Dark Green DGR Sodium Heparin, Lithium Heparin or Ammonium Heparin Anticoagulant. Tube is to be gently inverted (mixed) 8 times immediately after collection. Note: Sodium Heparin should not be used for Electrolyte determinations Laboratory Use HEPARINZED PLASMA For plasma determinations in chemistry. Tube inversions prevent clotting. Send whole blood in original tube. For plasma specimen, centrifuge within 45 minutes of collection, transfer plasma to a plastic tube marked "Plasma Sodium Heparin." Royal Blue RBL Red stripe- no additive Lavender stripe- Sodium-EDTA Anticoagulant Tube is to be gently inverted (mixed) 8 times immediately after collection Large yellow HEPARINIZED WHOLE BLOOD For trace element, toxicology and nutrient determinations. Special stopper formulation offers the lowest verified levels of trace elements available. Send in the original tube Tissue Typing - Not to be used for Blood Cultures ACD A or ACD B E. Blood Specimen Collection from a line Please refer to the Altoona Regional Health System s procedures regarding collection of blood culture samples from a line. F. Collection Errors Careful attention to routine procedures can eliminate most of the errors outlined in this section. The complete blood collection system and other collection materials provided by the laboratory can maintain the integrity of the specimen only when they are used in strict accordance with the instructions provided. 12

13 General Specimen Collection Errors: Some of the common errors affecting all types of specimens include: Errors in venipuncture preparation: 1. Failure to label a specimen correctly and to provide pertinent information. All specimens must be properly labeled in the presence of the patient. 2. Failure to check patient adherence to dietary restrictions before drawing. 3. Failure to calm patient prior to blood collection. 4. Use of improper equipment and supplies, i.e. incorrect container for appropriate specimen preservation. Errors in Venipuncture procedure: 1. Failure to dry site completely after cleansing. 2. Inserting needle bevel side down. 3. Use of a needle that has too small of a bore, causing hemolysis. 4. Prolonged tourniquet application. 5. Wrong order of tube draw. 6. Failure to mix blood collected in additive containing tubes immediately. 7. Pulling on a syringe plunger too forcefully. 8. Failure to release tourniquet prior to needle withdrawal. 9. Venipuncture in an unacceptable area: Avoid areas with hematomas, burns, scars, or swelling. Avoid the side on which a mastectomy was performed. If there is an IV infusion, whenever possible, blood should be collected from the opposite arm or from a site below the IV. Please refer to the Altoona Regional Health System s procedures regarding collection of specimens in the presence of an IV. Errors after venipuncture completion: 1. Failure to apply pressure to venipuncture site. 2. Vigorous shaking of anticoagulated specimens 3. Forcing blood through a syringe needle into tube. 4. Mislabeling of tubes. 5. Failure to use the correct container for appropriate specimen preservation. 6. Failure to tighten specimen container lids, resulting in leakage and/or contamination of specimens. 7. Insufficient quantity of specimen to run test or QNS (quantity not sufficient). 13

14 II. SPECIMEN PREPARATION A. Preparing Serum Serum Preparation from Red Stopper Tube: Follow the steps below when Preparing a serum specimen for submission. 1. Draw whole blood in an amount 2 and 1/2 times the required volume of serum so that the expected amount of serum can be obtained. EXAMPLE: A 10 ml red stopper rube will yield approximately 4 ml of serum after clotting and centrifuging. 2. Place the collection tube in the upright position in a test tube rack, and allow the blood to clot at room temperature for no longer than minutes. 3. As soon as possible after a clot has formed, insert the tube in the centrifuge, stopper end up. Operate the centrifuge for minutes at the speed recommended by the manufacturer. Do not allow prolonged centrifugation as this may cause hemolysis. When using a bench top centrifuge, employ a balance tube of the same type containing an equivalent volume of water. The tube stopper should remain. 4. Turn the centrifuge off and allow it to come to a complete stop. Do not stop it by hand or brake. Remove the tube carefully without disturbing the contents. 5. Remove the stopper and carefully aspirate most of the serum from the cells using a separate disposable Pasteur pipette for each tube. Place the tip of the pipette against the side of the tube, approximately 1/4 inch above the cell layer. Do not disturb the cell layer or carry any cells over into the pipette. If cells do enter the pipette, re-centrifuge the entire specimen. 6. Transfer the serum from the pipette into the plastic transfer tube. Inspect the serum for signs of hemolysis and turbidity by holding it up to the light. Be sure to provide the laboratory with the amount of serum specified. 7. Label the tube carefully and clearly with all pertinent information (refer to the specimen identification section). NEVER LEAVE THE PATIENTS BEDSIDE BEFORE PROPERLY LABELING THE SPECIMEN. Unless otherwise indicated, serum samples should be refrigerated until they are sent to the laboratory. When multiple tests requiring frozen serum are ordered, a plastic transfer tube should be prepared for EACH test. 8. When frozen serum is required, place the plastic transfer tube(s) immediately in the freezer. A separate frozen sample must be submitted for each test requiring a frozen specimen. Serum Preparation from Serum-Separator (SST) Tubes: Serum separator (Gold or Marble red/gray stopper) tubes contain clot activator and gel for separating serum From cells but include no anticoagulant. Adhere to the following steps when Using a serum-separator tube. 1. Draw whole blood in an amount 2 and 1/2 times the required volume of serum so that a sufficient amount of serum can be obtained. EXAMPLE: A 10 ml 14

15 Marble top tube will yield approximately 4 ml of serum after clotting and centrifuging. 2. Gently invert the serum-separator tube five times to mix the clot activator and blood. 3. Place the collection tube in the upright position in a test tube rack and allow the blood to clot a room temperature for no longer than minutes. Clots will usually form in minutes. 4. As soon as possible after a clot has formed, insert the tube in the centrifuge, stopper end up. Operate the centrifuge for minutes at the speed recommended by the manufacturer. Do not allow prolonged centrifugation as this may cause hemolysis. When using a bench top centrifuge, employ a balance tube of the same type containing an equivalent volume of water. The tube stopper should remain on the tube. 5. Turn the centrifuge off and allow it to come to a complete stop. Do not stop it by hand or use a brake. Remove the tube carefully without disturbing the contents. Inspect the barrier gel to ensure that it has sealed the serum from the packed cells. Also examine the serum for signs of hemolysis and turbidity by holding it up to the light. Be sure to provide the laboratory with the volume of serum specified. 6. Label the tube carefully and clearly with all pertinent information (refer to the specimen identification section). NEVER LEAVE THE PATIENTS BEDSIDE BEFORE PROPERLY LABELING THE SPECIMEN. 7. If a frozen specimen is not required, it is not necessary to transfer serum to a plastic transport tube. 8. When frozen serum is required, always transfer the serum (using a disposal pipette) into a separate, clearly labeled plastic transfer tube. Place the plastic transfer tube(s) immediately in the freezer. Never freeze a glass serumseparator tube. A separate frozen sample must be submitted for each test requiring a frozen specimen. B. Preparing Plasma Plasma Preparation from a Plasma Separator (PST) Tube: When plasma is Collected in a PST tube the following steps should be followed: 1. Always use the proper tube for tests requiring a special anticoagulant (i.e. EDTA, heparin, sodium citrate, etc.) 2. Tap the tube gently to release additive adhering to the tube or stopper diaphragm. 3. Permit the tube to fill completely. Failure to fill the tube will cause an improper blood-to-anticoagulant ratio and yield questionable tests results. 15

16 4. To avoid clotting, mix the blood with the anticoagulant or preservative immediately after drawing each sample. To ensure adequate mixing, slowly invert the tube five to six times using a gentle wrist rotation motion. 5. Immediately centrifuge the specimen for 5-10 minutes. Do not remove the stopper. 6. Turn the centrifuge off and allow it to come to a complete stop. Do not stop by hand or use a brake. Remove the tube carefully without disturbing the contents. 7. Make sure the tube is clearly labeled with all pertinent information (refer to the specimen identification section) NEVER LEAVE THE PATIENTS BEDSIDE BEFORE PROPERLY LABELING THE SPECIMEN. 8. If a frozen specimen is not required, it is not necessary to transfer plasma to a plastic transport tube. 9. When frozen plasma is required, always transfer the plasma (using a disposable pipette) into a separate properly labeled plastic transfer tube. Be certain to mark the tube as to the contents (Example: "Plasma, lithium heparin"). Place the plastic transfer tube(s) in the freezer. Never freeze a glass or plastic plasma separator tube. A separate frozen sample must be submitted for each test requiring a frozen specimen. Plasma Preparation from Non-SST Tubes: Follow the steps below the prepare plasma from all anticoagulated tubes that do not contain SST gel. 1. Always use the proper tube for tests requiring a special anticoagulant (i.e. EDTA, heparin, sodium citrate, etc.) or preservative. 2. Tap the tube gently to release additive adhering to the tube or stopper diaphragm. 3. Permit the tube to fill completely. Failure to fill the tube will cause an improper blood-to-anticoagulant ratio and yield questionable test results. 4. To avoid clotting, mix the blood with the anticoagulant or preservative immediately after drawing each sample. To ensure adequate mixing, slowly invert the tube five to six times using a gentle wrist rotation motion. 5. Immediately centrifuge the specimen for 5-10 minutes. Do not remove the stopper. 6. Turn the centrifuge off and allow it to come to a complete stop. Do not stop it by hand or brake. Remove the tube carefully without disturbing the contents. 7. Remove the stopper and carefully aspirate plasma using a separate disposable Pasteur pipette for each tube. Place the tip of the pipette against the side of the tube, approximately 1/4 inch above the cell layer. Do not disturb the cell layer or carry any cells over into the pipette. If the cell layer is disturbed, the specimen must be recentrifuged. Do not pour off; use the transfer pipette. 8. Transfer the plasma from the pipette into the transfer tube. Be sure to provide the laboratory with the amount of plasma specified. 16

17 9. Label all transfer tubes clearly and carefully with all required information. All tubes should also be marked as to their content (Example: "Plasma, sodium citrate"). 10. When frozen plasma is required, place plastic transfer tube(s) immediately into the freezer. A separate frozen sample must be submitted for each test requiring a frozen specimen. C. Preparation Errors Serum Preparation Errors: 1. Failure to separate serum from red cells within minutes of collection. 2. Hemolysis: Red blood cells broken down and components spilled into serum (see below). 3. Lipemia: Cloudy or milky serum sometimes due to the patient's diet. 4. Failure to allow complete clotting of the specimen prior to centrifugation. Plasma Preparation Errors: 1. Failure to mix tube immediately - full or partial clotting of specimen may occur. 2. Hemolysis - red blood cells broken down and components spilled into serum (see below). 3. Incomplete filling of the tube, thereby creating a dilution factor excessive for total specimen volume. 4. Failure to separate plasma from cells within minutes of collection. D. Hemolysis 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 is pink or red, rather than the normal clear straw color. Generally, hemolysis is the product of a poor venipuncture. A redraw will often yield an acceptable, non-hemolyzed specimen. III. CRITERIA FOR BLOOD SPECIMEN REJECTION 1. Improperly identified or unidentified specimens. 2. Specimen too old for accurate testing (refer to specific test for such time requirements). 3. Anticoagulated specimen that is partially or completely clotted. 4. Improper tube type used for specimen collection (i.e. wrong anticoagulant, serum rather than plasma, etc.). 17

18 5. Patient did not follow specific instructions associated with certain test procedures. Special instructions may be obtained by calling Altoona Hospital Department of Laboratory Services at (814) Quantity not sufficient for testing. One of the most common and expensive errors in specimen collection is the submission of an insufficient sample for testing. Although Altoona Regional Health System Laboratory will make every effort to complete testing on the specimen submitted, we may have to send out a report marked QNS (quantity not sufficient) and the patient will have to be called back for repeat collection at additional expense and inconvenience to the patient and to the physician. To ensure an adequate quantity of specimen: a. Always check the test section of this manual prior to venipuncture to determine the specimen type and quantity needed. b. Always draw whole blood in an amount 2 1/2 times volume of serum required for a particular test. Example: If 4 ml. of serum is required, draw at least 10 ml. of blood. NOTE: If you are not certain that the quantity of specimen collected is adequate for a particular test, call Altoona Hospital Department of Laboratory Services at (814) before releasing the patient. 18