PMLS 2 Lesson 6 Pre-Analytical Considerations in Phlebotomy PDF

PMLS 2  Heparin or Saline Lock – commonly called “hep- lock,” is an intravenous (IV) catheter attached to a LESSON 6 – PRE-ANALYTICAL CONSIDERATIONS IN...

PMLS 2  Heparin or Saline Lock – commonly called “hep- lock,” is an intravenous (IV) catheter attached to a LESSON 6 – PRE-ANALYTICAL CONSIDERATIONS IN stopcock or cap with diaphragm. PHLEBOTOMY  Intravenous (IV) Sites – IV line is a thin plastic tube or catheter inserted into a vein in the forearm ASSESSING HEALTH to inject a volume of fluids into the bloodstream. Pre- Analytical – testing phase includes procedures such as  Central Vascular Access Devices (CVADs) – laboratory handling and identification. also known as “indwelling lines,” are of the tubings inserted to the main vein or artery used for blood  Phlebotomist must not only be able to draw blood collection, monitoring the patient’s pressure, and from the patient, but must also be able to identify administering medications and fluids. factors that affect the process and address them needed. Three types of CVADs:  Physicians compare the results to a reference  Central Venous Catheter – also known as a range or reference interval. This range shows the central line inserted into the large vein HIGH and LOW limits of result values as (subclavian) and advanced into the superior compared to healthy individuals. vena cava.  Basal state is ideal in establishing reference range  Implanted Port – surgically implanted disk- since it represents the condition of the metabolism shaped chamber attached to the indwelling of the body early in the morning or approximately line. 12 hours of fasting.  Peripherally Inserted Central Catheter Problem Areas to Avoid Troubleshooting in the Site (PICC) – flexible tube inserted into the veins Selection of extremities and the central veins. Burns, Scars, and Tattoos – it is not advisable to choose a Handling Patient Complications Associated with Blood site that is in burns, scars, or tattoos because veins in the Collection area may be difficult to examine and blood circulation may be impaired.  Allergies to Equipment and Supplies – when the patient has adhesive allergy, a gauze should Damaged Veins – aside from being difficult to perform, be placed over the site and should be remove after puncturing damaged veins may also produce inaccurate 15 minutes. result.  Excessive Bleeding – when a patient is on aspirin or anticoagulant, the bleeding may take a Edema - also known as Oedema, is an abnormal swelling longer time. cause by the accumulation of fluid in the tissues.  Fainting – a temporary loss of consciousness which is caused by the insufficient flow of blood to Hematoma – solid swelling or a mass of blood in the tissues the brain. caused by the leakage of blood from the vessels during  Nausea and Vomiting – when the patient feels venipuncture. nauseous and has the tendency to vomit, the phlebotomist has to discontinue the procedure Mastectomy – procedure, often done to breast cancer until the patient feels better or until the feeling patients, refers to the removal of the breast through surgery. subsides. Obesity – condition in which the individual is grossly  Pain – the patient should be warned before the overweight. Patient who are obese have veins that are deep needle insertion, and the phlebotomist should and difficult to locate. avoid redirection of the needle.  Petechiae – the condition involves the Vascular Access Sites and Devices appearance of small red or purple spots that look like rashes, which appear on the arm when Vascular Access Devices (VADs) – needed for blood tourniquet is applied. sampling, infusing medication, central venous pressure  Seizures or Convulsions – when this occur, the readings, and blood transfusion of a patient. blood draw should be discontinued quickly. There must be pressure held over the site but it must be  Arterial Line – obtain samples for arterial blood made certain that movement is not restricted. gas and laboratory studies, critically ill patients require arterial lines where a thin catheter is Avoiding and Handling Procedural Error Risks and inserted into an artery. Failure to Draw Blood  Arteriovenous Shunt or Fistula – passageway created through surgery, and is usually in the arms Hematoma Formation- The phlebotomist should hold with the intention of connecting the artery and vein pressure over the site immediately after discontinuing directly. the draw. A cold compress or ice pack may be offered  Blood-sampling Device – used to avoid the use to help address the swelling. The following are of needle - sticks, prevent infections, and reduce conditions that trigger hematoma: wastage from line draws.  There is excessive or blind probing.   There is inadvertent arterial puncture. films and specimens; using the wrong  The size of the vein is too small. antiseptic; or simply not following the proper  The needle penetration has gone all through antiseptic procedure could interfere with the the vein. results.  Needle is not completely inserted. 5. Wrong or expired collection tube should not  Tourniquet is still on when the needle was be used because the manufacturer could not removed. warrant the quality of the seal and pressure  The pressure is not adequate. after the expiration date indicated in the tube. latrogenic Anemia- This results from blood loss due to Troubleshooting Failed Venipuncture blood draw. It is important to ensure that only the phlebotomist should ensure that the following do not happen: required specimen volume is collected because if 10% of the blood volume is removed at once from the body,  Needle not inserted far enough the patient could face a threat.  Bevel partially out of skin Inadvertent Arterial Puncture- This happens when  Bevel partially into vein blood is filling up the tube rapidly and there is a rapid  Bevel partially through vein formation of hematoma on the site.  Bevel completely through vein  Bevel against vein wal Infection - can be avoided by making sure that tapes or  Needle beside vein bandages are not opened ahead of time; needles are  Undetermined Position not preloaded into the tube holders; insertion site of the needle is not touched after sterilization; cap is removed Collapsed Veins – usually occur when conditions are less just before venipuncture; and patients are advised to than ideal, which leads to the veins being blocked, resulting keep the bandage on the site for 15 minutes. in insufficient blood flow. Nerve Injury - happen when there is improper site Tube Vacuum – to avoid failure due to loss of vacuum, the selection, rapid needle insertion, excessive redirection phlebotomist should make sure that the bevel is not partially of the needle, and blind probing. If the initial attempt is out of skin and the tube itself is not damaged. unsuccessful, the phlebotomist should try to redirect the needle by using a slightly forward or backward LESSON 7 – CAPILLARY PUNCTURE EQUIPMENT AND movement. The next step is to remove the needle and PROCEDURE look for an alternative site. Type of Equipment for Capillary Specimen Collection Reflux of Anticoagulant- Blood that has already been Capillary puncture – skin puncture is a method that uses a drawn flowing back into the vein from the collection lancet to make a small incision into the capillary bed of the tube may cause adverse reaction because of the skin to obtain a small volume of blood specimen. presence of tube additives. To avoid this, make sure that the arm of the patient is in a downward position Following are the pieces of equipment used for capillary and the tube is just below the venipuncture site. collection: Vein Damage- Damaging the vein could be avoided by  Lancet/Incision Devices – sterile, sharp following the proper technique and avoiding blind instruments that are intended for one-time use probing. only. Designed for used in making cuts in the skin for finger or hill puncture. Specimen Quality  Laser Lancet – type of lancet that produces a 1. Hemoconcentration is a decrease in the fluid small hole in the skin by vaporizing water in the content or plasma volume which is usually skin. caused by tourniquet that stagnates the  Microcollection container- also known as normal flow of blood leading to the increase microtube, this container is a small plastic tube in concentration of red blood cells and other used to hold blood specimen collected in the non-filterable large molecules. capillary puncture. 2. Hemolysis, which is also called haemolysis,  Microhemotocrit tubes and sealants – narrow refers to the rupture of the red blood cells. bore tubes that are made of either plastic or glass. The hemoglobin is then released into the Typically used for hematocrit determinations. surrounding fluid.  Microscope slides – these are used for blood 3. Partially filled tube or short draw, happens films for hematology determinations. when the phlebotomist pulls a tube before  Waring devices – these are used to increase the reaching the required volume. This may lead blood flow seven-fold by warming the puncture site. to the incorrect blood-to-additive ratio.  Capillary Blood Gas (CBG) equipment – special 4. Specimen contamination means that the equipment used for collection of capillary blood specimen is compromised due to incorrect gas (CBG) specimen, which contains CBG handling, which involves allowing alcohol, collection tubes, stirrers, magnet, and plastic cups. powder or other materials into the sample. Getting glove powder or perspiration into Composition of Capillary Blood Specimen and the Test draw should be capillary blood gas specimens (CBs), EDTA and Capillary Reference Value specimens, other additive specimens, and serum specimens. Capillary blood specimen - is a mixture of different blood and fluid which include the following: arterial blood, venous blood, capillary blood, interstitial fluid, and intracellular fluid.  Arterial blood – bright red blood found in the pulmonary vein, left chamber of the heart, and the arteries. Oxygenated blood of the circular system.  Venous blood – the blood that travels from the peripheral veins passing through the venous system then through the right chamber of the heart. Dark red in color because it is deoxygenated.  Capillary Blood – the preferred specimen for infants, young children, elderly patients, and patients with severe burns. Extracted from venules and arterioles found in the capillary bed.  Interstitial Fluid – fills the spaces around the cells, Procedure for Selecting the Puncture Site and Collecting filtered from the blood capillaries, and drained Capillary Specimens from Adults, Infants, and Children away as lymph.  Intracellular Fluid – found inside the cells. Capillary Puncture Steps Facilitates the movement of the fluid in the membrane and block the entrance of unwanted (1) Review and check accession test request materials. (2) Approach, identify, and prepare the patient (3) Verify diet restrictions and latex sensitivity Indications of Performing Capillary Puncture on Adults, (4) Sanitize hands and put on gloves Children, and Infants (5) Position the patient (6) Select the puncture or incision site Capillary specimen could be a good alternative to (7) Warm the site if necessary venipuncture for adults and older children under the following (8) Clean and air-dry the site circumstances: (9) Prepare the equipment (10) Puncture the site and discard the lancet  veins are fragile and not accessible because of (11) The first blood drop should be wipe away because scars and burns; it may be contaminated with excess tissue fluid  (2) veins are reserved for another procedure such (12) Fill and mix tubes or containers in the order of as chemotherapy; draw  (3) clotting tendencies; (13) Place gauze and apply pressure. Keep the incision  (4) extreme fear of needles; and site elevated  (5) veins will be used for glucose monitoring or (14) Label specimen and observe special handling oral glucose tolerance test (OGTT). instructions (15) Check the site and apply bandage This is also the preferred method for infants and young (16) Dispose of used and contaminated materials children because of the following reasons: (17) Thank patient, remove gloves, and sanitize hands (18) Transport specimen to the lab  (1) health risks such as anemia and cardiac arrest;  (2) requires only a small volume of blood; Reasons for Making Routine Thin Blood Film and Thick  (3) venipuncture could damage veins and tissues Blood Smear Preparation surrounding the site;  (4) puncturing could result in hemorrhage,  Routine blood film/smear preparation is a blood thrombosis, gangrene, and infection; test that is used to check abnormalities in the  (5) risk of injury because of the restraint needed in blood cells. A small drop of blood is placed near venipuncture; and the frosted end of the glass side. Another slide is  (6) capillary blood is the preferred specimen. used to spread the blood in a thin film over the slide. It is then air-dried and stained. Capillary puncture should not be used for erythrocyte  Thick blood smear preparation is used to sedimentation rate methods, blood cultures, and studies that determine if the patient has malaria, which is need plasma specimen or have large volume specimen diagnosed by its presence in the peripheral blood requirement. smear. The procedure starts by placing a large drop of blood in the center of the slide. The blood Order of Draw for Collecting Capillary Specimen drop is spread until it is about the size of a dime, using a cover slip or another slide. This should be Order of draw refers to the specific sequence with which air-dried for at least 2 hours before staining. blood must be drawn and collected in tubes to avoid cross- contamination of additives between the tubes. The order of Collection of Specimen for Capillary Blood Gas, Neonatal Bilirubin, and Newborn Screening Tests and Its Clinical Significance  Capillary blood gas specimen by heel puncture is recommended for infants and small children. The blood samples are collected on the same site as routine capillary puncture specimens.  Neonatal bilirubin collection is used to help determine any liver disorder in infants. This is collected with a heel stick. Specimen Required: Supplies: Amber-frosted tube, 5 mL (T192) Collection Container/Tube: Preferred: 2 Serum gel microtainers Acceptable: 2 Red-top microtainers Submission Container/Tube: Amber vial (T192) Specimen Volume: 0.5 mL Collection Instructions: (1) Serum gel microtainers should be centrifuged within 2 hours of collection. (2) Red-top microtainers should be centrifuged and aliquoted within 2 hours of collection.  Newborn/neonatal screening is done as part of the routine check for infants to determine inborn disorders such as phenylketonuria, hypothyroidism and galactosemia, and cystic fibrosis.  Newborn screening blood spot collection is done 24 to 48 hours after the baby is born, in which a few drops of blood are collected through heel stick to determine disorders that are not apparent at birth and could lead to disability or even death. LESSON 8 - SPECIAL COLLECTIONS AND POINT OF CARE TESTING Name of test Purpose Special requirement (if Blood collection top Section of any) color used laboratory it covers Blood bank: Determines the blood type none Lavender (EDTA) / Red Immunohematology blood type and and Rh factor (serum, no additive) screen Blood bank: Check the capability between Patients serum of plasma Lavender (EDTA) / Red Immunohematology cross match the donors and the recipients and donors RBCs (serum, no additive) test blood Blood culture Determines the presence of Blood volume should be 20 Yellow (SPS) or Blood Microbiology infection, identifies the type of to 30mL per culture with a Culture Bottles organism involved, and minimum of 10mL per draw meassures the extent of for patients weighing more infection than 80 pounds. For infants, t should be only 1% to 4% of the total blood volume Coagulation Evaluates the blood clotting Microclots are avoided by Light Blue (Sodium Hematology test function gently inverting Citrate) anticoagulants tubes three or four times after collection 2 - hour Screens for diabetes and Must be obtained 2 hours Gray (Sodium Clinical chemistry postprandial other metabolic disorders after meal Fluoride/Potassium glucose Oxalate) Glucose Diagnoses problems in 1 hour for gestational Gray (Sodium Clinical chemistry tolerance test carbohydrate metabolism and diabetes and 3 hours for Fluoride/Potassium (GTT) and Oral checks the ability to other glucose metabolism Oxalate) glucose metabolize glucose through evaluation tolerance test the tolerance level (OGTT) Lactose Determine the lack of mucosal Same procedure as 2-hour Gray (Sodium Clinical chemistry Tolerance test lactase which is responsible GTT but an equal amount of Fluoride/Potassium for conversation of lactose lactose is substituted for Oxalate) into glucose glucose Paternity/parent Verifies the probability that the Follows the chain-of-custody Yellow (ACD - Acid Genetics / Molecular age testing patient fathered a particular protocol and specific Citrate Dextrose) or Diagnostics child identification procedures Lavender (EDTA, depending on test requirements) Therapeutic Tests the drug levels at Collection timing should Red (Serum, no additive) Toxicology drug monitoring specific intervals to establish include the peak and trough or sometimes Green proper drug dosage and avoid levels (Heparin, depending on toxicity drug tested) Therapeutic Treats polycythemia and Involves withdrawal of Red (Serum) or a Phlebotomy/special phlebotomy hemochromatosis approximately 500mL as part Standard Blood procedures of the treatment Collection Bag Toxicology test Checks the presence of toxins Toxins usually exist in the Red (Serum, no additive) Toxicology in the blood, hair, urine, and very small amounts or sometimes Gray other substances (Sodium Fluoride for alcohol testing) Trace elements Checks the presence of Measured in small amounts Royal Blue (EDTA, Toxicology aluminum, arsenic, copper, Heparin, or No Additive, lead, iron, and zinc depending on the test) Blood Bank Specimens  RBCs, plasma, platelets – Must be traceable to the donor.  Look-Back Program – Blood recipients must be Importance of Blood Bank Specimens notified if the donor is later diagnosed with a disease.  Determines safe blood for transfusion.  Collected in lavender-top (EDTA), pink-top (EDTA), Autologous Donation: or red-top (non-additive serum tube).  Patients donate their own blood for future use (e.g., Proper Identification & Labeling elective surgeries).  Reduces transfusion risks.  Must be collected at least 72 hours before surgery. Required Information: Cell Salvaging (Intraoperative Blood Recovery): 1. Full name (including middle initial) 2. Hospital ID number  Blood lost during surgery is collected, washed, and 3. Social Security number (for outpatients) re-infused. 4. Date of birth  Residual free hemoglobin levels must be tested 5. Date & time of collection before reinfusion. 6. Initials of the phlebotomist  High hemoglobin levels can cause renal dysfunction, making reinfusion unsafe. Optional: Room number & bed number Sterile Technique in Blood Culture Identification Methods: Purpose of Blood Culture  ID bracelet  Detects bacteremia (bacteria in the blood) and septicemia (bacteria & toxins in the blood).  Self-carbon adhesive specimen label  ID band (barcoded)  Ordered when patients have fever of unknown  Patient identification check-blood administration origin (FUO) to check for bloodstream microorganism invasion. Blood Bank Tests  Helps determine the causative organism and appropriate antibiotic treatment.  Blood Typing (ABO & Rh factor) – Ensures Blood Culture Collection compatibility for transfusion.  Screening for infectious diseases – Prevents  Ideal Collection Requirements/Optimum reslults: disease transmission. 2 to 4 sets of blood cultures should be  Crossmatch Test – Ensures donor and recipient collected. blood compatibility by mixing plasma/serum with donor RBCs. Special bottles used: Blood Donation & Phlebotomy  Aerobic (with air)  Anaerobic (without air) Purpose: Mainly for transfusion. Performed by trained phlebotomists with excellent Samples should be drawn 30 to 60 minutes venipuncture skills. apart for accurate detection. Sterile Technique in Blood Culture Collection Blood Donor Requirements: Age: 17 - 66 years old  Skin antisepsis - crucial in the blood collection Weight: Minimum 110 lbs procedure Physical exam & medical history must be completed Brief donor exam before collection  Importance: Prevents contamination by microbial skin Written permission required Blood components must be traceable for safety flora that may affect results.  Sterile Site Preparation: Blood Components & Special Donations Common antiseptics used: Blood Unit Separation:  Betadine swab sticks  Chloroprep   PVP ampule 14. Dispose of used materials properly to maintain hygiene.  Friction Frepp/Sepp II 15. Thank the patient, remove gloves, and sanitize hands.  Benzalkonium chloride 16. Transport the specimen promptly to the laboratory for Proper Antiseptic Application: analysis.  Friction rub of collection site for 30 - 60 Media Inoculation Methods seconds. Three Ways to Inoculate Blood Culture Medium  Use tincture of iodine, chlorhexidine gluconate, or povidone-iodine/70% ethyl  Direct Inoculation (During Collection) alcohol combination. Uses butterfly needle with a specially designed Reporting & Interpretation holder.  If a microorganism is detected, the laboratory must Connected to the Luer connector of the butterfly set. report it. Aerobic vial is filled first, followed by anaerobic.  The physician evaluates if the microorganism is clinically Needle is removed, and the safety device is significant or a contaminant. activated. Blood Culture Collection Procedure  Syringe Method (After Collection) Importance of Proper Blood Culture Collection Blood is drawn first into a syringe.  Blood culture must be the first priority in the order of A safety transfer device is used to transfer blood into draw to prevent contamination. culture bottles.  Following proper aseptic techniques ensures accurate Blood is drawn into the bottle via vacuum by pushing results. the syringe. Step-by-Step Blood Culture Collection Bottle must be placed on a solid surface to prevent contamination. ✅ Before Collection:  Intermediate Collection Tube (Laboratory Transfer) 1. Identify the patient properly and explain the procedure. Blood is first collected into an SPS tube (yellow-top) 2. Apply the tourniquet and release it within 60 seconds. before being transferred to culture bottles in the lab. 3. Assemble equipment and maintain proper aseptic technique. Not recommended due to: ✅ Skin & Bottle Preparation:  Increased SPS concentration affecting results. 4. Perform friction rub for about 60 seconds to disinfect the site.  Higher risk of contamination. 5. Allow the site to dry for 30 seconds before proceeding. Only used if necessary. 6. Remove flip-off cap from the culture bottle (check for defects). ✅ Best Practice Recommendation: Direct inoculation or syringe method is preferred over intermediate collection tubes 7. Disinfect bottle stopper while waiting for the site to dry. to minimize contamination risks. 8. Check fill lines on the bottle for proper blood volume. Coagulation Specimens ✅ Blood Collection & Inoculation:  Used to assess blood clotting functions, especially in 9. Reapply the tourniquet and perform venipuncture (avoid cases of unexplained bleeding. touching the cleaned site).  Common tests: 10. Inoculate the medium by transferring blood into the bottle. Prothrombin Time (PT) – Evaluates the extrinsic 11. Mix blood with medium by inverting the bottle a few times. pathway of coagulation. ✅ Post-Collection Procedures: Activated Partial Thromboplastin Time (aPTT) – Assesses the intrinsic pathway. 12. If iodine was used, clean the patient's skin after collection. Thrombin Time (TT) – Measures fibrin formation 13. Label the specimen properly, including collection site and the final step of clotting. details.  Requires proper handling to prevent inaccurate results.  Gestational diabetes test: 50-75g glucose. Coagulation Specimen Collection Procedure 5. Patient must ingest glucose within 5 minutes. 1. If collecting only a coagulation specimen, first draw a 6. Record the exact time the drink was finished. discard tube (1-2 mL in a clear tube). Use a light blue-top tube (3.2% sodium citrate) with a 9:1 blood-to- 7. Start timing for blood collections at 30 minutes, 1 hour, 2 anticoagulant ratio. hours, etc. 2. Invert the tube gently 3-4 times immediately after 8. Label samples properly with the collection time and intervals. collection for proper mixing. 9. Transport specimens immediately to the lab (within 2 hours) 3. When using an evacuated tube system, collect for accurate results. coagulation samples secondarily. Lactose Tolerance Test (LTT) 4. For indwelling catheters:  The LTT evaluates the body's ability to process lactose.  Draw and discard 5 mL of blood before collecting the specimen.  It determines if the patient lacks mucosal lactase, an enzyme that converts lactose into glucose or galactose.  If heparin is used, flush with 5 mL of saline before collecting blood.  Lactose intolerance leads to gastrointestinal distress (diarrhea, bloating) after consuming dairy products. 5. Adjust sodium citrate concentration if the patient has hematocrit >55%. Principles of LTT: 6. Transport the specimen immediately to the laboratory. 1. Recommended 2-hour GTT test be administered at least a day before the lactose tolerance test.  If delayed beyond 4 hours, centrifuge and freeze the plasma. 2. Equal amount of lactose substituted to glucose but the test will performed following the manner of GTT. Glucose Tolerance Test (GTT) 3. Glucose specimen drawn at the same time as the previous  Evaluates how well the body metabolizes glucose by GTT procedure. measuring insulin response. 4. GTT curve and glucose curve will be similar if patient has  Used to diagnose carbohydrate metabolism disorders mucosal lactase (e.g., diabetes mellitus). 5.. If patient is lactose intolerant, result will yield a “flat” curve  Also called as Oral Glucose Tolerance Test (OGTT) where glucose levels just slightly rise over fasting level.  Standard GTT duration: 6. Patient with slow gastric emptying, Crohn’s disease and cystic fibrosis can show false-positive results. 1 hour for gestational diabetes. Paternity/ Parentage Testing 3 hours for other evaluations.  performed to exclude the possibility of paternity of Sample collection method must be consistent (venipuncture or particular child. skin puncture).  Before advent of DNA parenting testing, testing for GTT Procedure parentage involves ABO and Rh typing and basic red cell antigen testing. 1. Pre-test preparation:  If result thus not exclude alleged parent, further test  The patient must eat a balanced diet with 150g of involves; carbohydrates for 3 days. Extended red blood cell antigen  Fast for 12-16 hours before the test (only water allowed). Red cell enzymes 2. Collect fasting blood sample and check glucose level (must be ≤200 mg/dL for test to proceed). Serum protein testing 3. If required, collect fasting urine sample before administering White cell enzymes glucose. White cell antigen 4. Administer glucose beverage: Human leukocyte antigen (HLA)  Adults: 75g glucose.  DNA paternity testing - uses genetic fingerprinting/DNA  Children: 1g glucose per kg of body weight (50-75g max). profiling to established parentage providing genetic proof.  Polymerase chain reaction (PCR) and Restriction  Polycythemia - overproduction of red blood cells that is fragment length polymorphism (RFLP) - two methods harmful to the patient. used today Removal of blood is done with Hemotocrit is used Principles of DNA paternity testing to check the RBC level 1. All involved parties need to submit a government issued it is done with the goal of returning the levels to photo identification along with completed chain-of-custody form. normal range. All photos of all tested are taken.  Hemochomatosis - excess iron deposits in the tissues 2. Buccal samples are collected using swab that was rubbed which could be due to problems with iron metabolism inside the cheek where loose cheek skin cells can be gathered. cause by multiple blood transfusion or excessive intake of iron. 3. Sealed and tamper-evident packaged used to hold specimen during transport to the laboratory. Procedure is done through periodic removal of single units of blood which gradually deplete the 4. Test result are ready after 48 hours and are usually sent via excess iron in body. mail. Toxicology Specimens Therapeutic Drug Monitoring  Clinical toxicology - detection of toxins and treatment  Therapeutic Drug Monitoring (TDM) is the measurement of drug levels at specific time intervals.  Forensic toxicology - legal consequences of toxin exposure  Ensures that the drug concentration stays within the therapeutic range (effective but not toxic). Toxicology test:  Used for drugs with a narrow therapeutic index, where Collection of blood small variations in dose can cause toxicity or ineffectiveness. Collection of Hair Process of TDM Collection of Urine  Initial Dosage Prescription Other substance from the body purpose of determining presence of toxins Based on the patient's clinical condition. Forensic Specimens The drug level in the bloodstream rises to a peak (maximum level) and gradually falls to a trough  Toxicology specimens are ordered by the law - (minimum level). enforcement agencies for legal or forensic purposes.  Peak and Trough Levels  Most common specimens are Breath and Blood for alcohol. Peak Level: Maximum drug concentration, helps assess drug toxicity.  Other request specimens: Trough Level: Minimum drug concentration, Urine for drug screening ensures sufficient drug levels before the next dose. Blood for drugs and DNA analysis  Timing of Collection  Chain of Custody - special protocol that used by Important for aminoglycoside drugs (e.g., amikacin, releasing forensic specimen that is need to track the gentamicin, tobramycin) due to their short half-lives. specimen from the time of collection until the time of results are released Less critical for drugs like phenobarbital and digoxin. Important information about collection of specimen is recorded in the chain of custody, includes:  Clinical Considerations/Clinical outcomes  Type of specimen Drug dosage and history of administration.  Phlebotomist who made the collection Patient's response to the medication.  Technician who processed the specimen Desired therapeutic outcome.  Details of collection (time, date, and place) Therapeutic Phlebotomy  Signature of the specimen owner  performed by drawing a large volume of blood about 500mL from patient as part of treatment procedure for Packaging is done in presence or a witness who is polycythemia and hemochromatosis. law enforcer.  The person responsible for legal reasons is 5. The specimen must be protected from tampering. After summoned to appear before the court witness collection it should be sealed in a lock container and sent to the laboratory immediately. Documentation should be handled Blood Alcohol (Ethanol) Specimens carefully.  Blood Alcohol (ethanol [ETOH]) tests - usually Trace elements ordered for purposes related to treatment, also for industrial or job-related reasons such as insurance  Trace element/mineral testing detects the presence of claims or programs and employee screening. aluminum, arsenic, copper, lead, iron, and zinc in specimens.  Law enforcement department orders Blood Alcohol Custody (BAC) for individuals in traffic-related accidents.  Specimen Collection: BAC test for industrial and legal samples should Specimens are collected in small amounts. follow the chain of custody protocol Use element-free tubes (royal blue cap) to prevent  ETOH test treatment purposes does not require Chain of contamination from tube materials. Custody to accomplished but test result can evidence in court.  Tube Additives & Their Color Codes:  ETOH specimen collection uses; Red (no additive) aqueous povidone-iodine Lavender (EDTA - anticoagulant) aqueous benzalkonium chloride (BZK). Green (Heparin - anticoagulant)  Avoid using isopropyl alcohol and tincture of iodine as  Precautions to Avoid Contamination: antiseptics, these might affect the results. Just use Plain soap and water if abovementioned antiseptics or their Change the transfer device before filling the tube. alternative are not available. Point-of-Care Testing (POCT)  Uses Gray-top sodium flouride glass tubes for  POCT refers to any analytical test conducted outside a specimen collection. This can be with the anticoagulant centralized laboratory, near the patient’s treatment site. but depends of the needs of required specimen for specific test.  Other Names: Drug Screening Alternate Site Testing (AST)  Companies, healthcare organizations, and sports Bedside Testing association subject their potential employees to drug screening as part of their pre - employment requirement. Near-Patient Testing  Can be run random screening without prior notice. Remote Testing  Specimen used is Urine instead of blood. Satellite Testing  Chain of custody protocol is strictly implemented since Rapid Diagnostics legal implications are involved.  Types of POCT Simple Procedures: Patient preparation requirements Dipstick tests 1. The purpose and procedure should be explained to the patient Handheld glucose meters 2. The patient should be advised about his legal rights  Advanced Procedures Automated molecular tests using portable analyzers and imaging systems. 3. There should be a witness present when the form is signed Convenience: Can be performed at the patient’s Specimen collection requirements location. 1. Special area should be designated for the purpose of urine Faster Results: Reduces Turnaround Time (TAT), collection leading to quicker decision-making in patient care. 2. During the collection, a proctor is present to ensure that the Quality and Safety in POCT specimen came from correct person Quality Control (QC) in POCT 3. Split sample may be used for parallel testing  QC and maintenance procedures ensure accurate 4. Proper labeling should be followed to establish a chain of results. custody  POCT results should be as reliable as those from a Steps in Bleeding Time Test centralized laboratory. 1. Identify the patient properly. Follow proper hand hygiene  Waived tests are increasing but require less stringent quality control than non-waived tests. 2. Ask the patient if they have taken aspirin or salicylate- containing drugs in the past two weeks, as this can affect the Electronic Quality Controls (EQCs): result. Inform the patient about possible scarring.  Detect specimen-related problems. 3. Place the patient’s arm on a steady surface for support.  Internal checks assess instrument functionality. 4. Choose a site 5 cm distal to the antecubital area on the volar lateral forearm. Shave if necessary and ensure no scars,  Ease regulatory requirements for POCT. bruises, or edema. Quality Checks: 5. Place a blood pressure cuff around the arm. Instrumented tests: Use EQCs for accuracy. 6. Use alcohol to clean the site and let it air dry. Non-instrumented tests: Use daily external liquid QC checks 7. Wear gloves and prepare the equipment while waiting for to ensure proper techniques and reliable results. the site to dry. Infection Control in POCT instruments: 8. Open the puncture device and keep the blade sterile.  Handheld analyzers may transmit infections. 9. Inflate the blood pressure cuff to 40 mmHg.  Disinfection with 10% bleach is recommended to reduce 10. Remove the safety clip and position the puncture device. contamination. 11. Depress the trigger and start the timer immediately. Coagulation Monitoring by POCT Remove the blade and discard it properly.  Warfarin and heparin therapy can be evaluated using a 12. Use a filter paper every 30 seconds to blot blood flow coagulation POCT analyzer. without touching the wound.  Common coagulation tests checked: 13. Stop the timer when bleeding stops and no longer stains the filter paper. If bleeding persists beyond 15 minutes, stop Prothrombin time (PT) and international the test. normalized ratio (INR) 14. Remove the blood pressure cuff, clean the arm, and Activated partial thromboplastin time (APTT or PTT) bandage the wound. Advise the patient to keep the site and bandage intact for the next 24 hours. Activated clotting time (ACT) 15. Record the bleeding time and round to the nearest 30 Platelet function seconds. Normal results: 2 to 8 minutes.  Available POCT Instruments 16. Dispose of used and contaminated materials properly. Cascade POC – ACT, APTT, PT/INR Thank the patient before leaving. CoaguChek XS Plus – PT/INR Arterial Blood Gases and Electrolytes GEM Premier 4000 – ACT, APTT, PT/INR  Many healthcare institutions support the use of POCT for arterial blood gases (ABGs) and electrolytes in selected i-STAT – ACT, PT/INR settings such as: Verify Now – Platelet function Emergency department Bleeding Time Pulmonary unit  Bleeding time (BT) test is a non-instrumented test Neonatal intensive care unit ordered by the physician to evaluate capillary function and platelet plug formation.  These tests are more expensive than traditional pre- analytic and analytic laboratory tests.  It is used for pre-surgical screening and to detect problems involving hemostasis.  However, they greatly reduce turnaround time, allowing for faster medical diagnosis and prescription.  Although the coagulation test (BT assay) is now preferred, BT is still used in certain cases. Arterial Blood Gases (ABG)  Proper technique is essential for accurate results.  Measures the level of: Oxygen  Carbon dioxide Functions of Electrolytes Acid-base (pH) in the blood Sodium (Na⁺ ) - Maintains fluid balance and helps in nerve impulse transmission.  Provides insight into the function of the lungs, heart, and kidneys.  Hypernatremia – Elevated sodium levels.  ABGs measured by POCT methods include:  Hyponatremia – Reduced sodium levels. pH Potassium (K⁺ ) - Essential for nerve conduction and muscle function. Partial pressure of carbon dioxide (PCO₂)  Regulates acid-base balance and osmotic pressure. Partial pressure of oxygen (PO₂)  Hyperkalemia – Increased potassium levels. Oxygen saturation (SO₂)  Hypokalemia – Decreased potassium levels.  Key Parameters Chloride (Cl⁻ ) - Maintains cell integrity by balancing osmotic pH - Refers to the concentration of hydrogen ions pressure. in a solution.  Regulates acid-base and water balance.  The arterial pH test checks the acid-base balance. Bicarbonate Ion (HCO₃⁻ ) - Helps transport carbon dioxide (CO₂) to the lungs.  Normal range: 7.35 to 7.45.  Regulates blood pH.  Indicates metabolic and respiratory status.  CO₂ removal → Reduction in H⁺ ions → Increased PCO₂ (Partial Pressure of Carbon Dioxide) - blood pH. Measures gas exchange between blood and lungs.  Hypoventilation → Higher CO₂ → More H⁺ ions →  Indicates pressure exerted by dissolved CO₂ Acidosis. in the blood.  Hyperventilation → Lower CO₂ → Alkalosis.  Hypoventilation → Increased PCO₂ level. Ionized Calcium (iCa²⁺ ) - Comprises 45% of blood calcium.  Hyperventilation → Decreased PCO₂ level.  Essential for: PO₂ (Partial Pressure of Oxygen) - Represents the pressure exerted by dissolved O₂ in the blood Muscular function plasma. Cardiac function  Determines the effectiveness of oxygen therapy. Blood clotting SO₂ (Oxygen Saturation) - Indicates oxygenation Nerve transmission status of the patient. Multiple-Test Panel Monitoring by POCT  Measures the percentage of hemoglobin  Composed of small, portable testing devices. binding with oxygen.  Measures analytes such as:  Normal oxygen saturation: 98%. Sodium, potassium, chloride, bicarbonate ion Electrolytes Electrolytes help in moving nutrients and removing Blood gas values (potential hydrogen, PCO₂, PO₂)  wastes in the body's cells. BUN, glucose, hemoglobin, hematocrit, ACT, lactate, POCT electrolyte panels determine blood levels of: troponin   Short turnaround time makes it useful in emergency Sodium (Na⁺ ) conditions. Potassium (K⁺ ) Chloride (Cl⁻ ) Bicarbonate ion (HCO₃⁻ ) Ionized calcium (iCa²⁺ ) Instruments and Available Tests Pregnancy Test - Detects hCG. Instrument Analytes/ blood gas values tested Skin Test - Identifies allergic reactions & antibodies (e.g., TB, Aspergillus, coccidioidomycosis, histoplasmosis). GEM Premier Lactate, potassium, BUN, and creatinine Strep Testing - Detects group A streptococci. i - Stat BUN, glucose, Hbg and Hct, and ACT Urinalysis - Involves physical, chemical, microscopic urine values analysis. Avoximeter tHb, SO₂, O₂Ct, COHb, LESSON 9 - HANDLING AND PROCESSING OF BLOOD MetHb, %O₂Hb SPECIMENS FOR LABORATORY TESTING ABL80 Flex pH, PCO₂, PO₂, cNa, cCa2+, cCl−, Steps Involved in Processing and Handling Different cK+, Hct, cGlu Types of Specimens  Laboratory errors occur mostly in the pre-analytical phase (about 46%-68% of errors). Other Tests Performed by POCT  Proper collection, storage, processing, and transporting Pregnancy Testing - Detects pregnancy as early as 10 days protocols must be followed. from conception.  Phlebotomists are responsible for ensuring all steps are  Checks for β-subunit of human chorionic gonadotropin performed correctly. (hCG) in urine or serum. Routine Handling - Phlebotomists should have the necessary  No special preparation needed. knowledge and skills in venipuncture. Steps in Pregnancy Testing:  Care should be taken in mixing tubes and preparing specimens for transport. 1. Implement proper patient identification.  Time limits for delivery must be followed unless 2. Write patient ID on the specimen cup. exceptions apply (e.g., emergency cases). 3. Explain the collection procedure to the patient. Mixing Tubes by Inversion - Some tests require gentle inversion of the specimen tube to distribute 4. Place the test device on a flat surface. the additive. 5. Use the dropper to place 3 drops in the sample well.  The usual number of inversions is 3 to 10, depending on the type of additive 6. Wait for the reaction time (about 3 minutes) or as directed by the manufacturer. Transporting Specimens 7. Read the result from the cassette’s window.  Proper handling is necessary to avoid: Troponin T (TnT) and Troponin I (TnI) - Measures  Hemolysis of specimens effectiveness of thrombolytic therapy for heart attack patients.  Activation of platelets Lipid Testing - Measures alanine transferase (ALT) in patients on lipid-lowering therapy.  Coagulation issues B-Type Natriuretic Peptide (BNP) - Differentiates between  Breakage of glass tubes COPD and CHF.  Specimen tubes should be transported with C-Reactive Protein (CRP) - Detects infection, tissue injury, the stopper to: inflammation.  Avoid contact between the contents and Glucose - Monitors glucose levels in diabetic patients. the stopper. Glycosylated Hemoglobin - Diagnostic tool for diabetes  Minimize agitation of the specimen. therapy monitoring.  Aid clot formation for serum tubes. Hematocrit - Measures volume of red blood cells.  Tubes must be placed in liquid-tight plastic Hemoglobin - Assesses anemia management. bags with: Lactate - Evaluates lactic acid disorder severity & stress  A visible biohazard logo response.  A slip pocket for paperwork/documentation Occult Blood (Guaiac) - Detects GIT bleeding. Special Handling - Special care is needed when handling 2. Inadequate volume to complete the test. blood specimens to protect their condition and quality. 3. Hemolysis is present.  Body Temperature - Specimens may precipitate or agglutinate if allowed to cool below body temperature. 4. Wrong tube for collection is used. Must be transported at 37°C (near body 5. Tube used is outdated. temperature). 6. Improper handling (e.g., incorrect mixing). Tubes should be pre-warmed and transported with portable heat blocks (holding temperature for 15 7. Specimen is contaminated. minutes). 8. Insufficient specimen or "quality not sufficient" (QNS). Heel warmers can be used for specimens needing a 9. Incorrect collection time. slightly higher temperature. 10. Exposure to light.  Examples: Cold agglutinin, cryofibrinogen, and cryoglobulins. 11. Procedure did not follow testing time limits.  Chilled Specimen - Chilling slows metabolic processes, 12. Delay or error in processing. preventing result alterations. Delivery Time Limits and Exceptions for Delivery and Specimen tubes should be submerged in crushed Processing Specimens ice and water slurry during transport. Delivery Time Limits - Specimens should be transported Should be immediately tested or refrigerated if immediately after collection. necessary.  Routine blood specimens should reach the laboratory  Examples: within 45 minutes. Adrenocorticotropic hormone (ACTH), acetone, angiotensin-converting enzyme  Centrifugation (if needed) should be done within 1 hour. (ACE), ammonia, catecholamines, free fatty acids, gastrin, glucagon, homocysteine,  Hematology specimens with EDTA (lavender or purple lactic acid, parathyroid hormone (PTH), stopper) should not be centrifuged. pH/blood gas (if indicated), pyruvate, and renin. Time Limit Exceptions - STAT or emergency specimens take priority over all others.  Light-Sensitive Specimen - Exposure to light can affect certain test results (e.g., bilirubin).  Other exceptions to time limits include: Tubes should be wrapped in aluminum foil or stored Blood smear from EDTA specimen – prepared 1 in a light-blocking, amber-colored container. hour from collection.  Examples: EDTA specimen for CBC – analyzed within 6 hours, Bilirubin, carotene, red cell folate, serum stable for 24 hours at room temperature. folate, Vitamin B₂, Vitamin B₆ , Vitamin B₁₂, EDTA specimen for ESR (Erythrocyte Vitamin C, urine porphyrins, and urine Sedimentation Rate) determination – tested 4 porphobilinogen. hours (room temp.), 12 hours (refrigerated). Blood Specimen Processing and Reasons for Specimen EDTA specimen for reticulocyte counts – stable Rejection for 6 hours (room temp.), 72 hours (refrigerated). Collected specimens go through the central processing or Glucose test in sodium fluoride tubes – stable for triage for: 24 hours (room temp.), 48 hours (refrigerated at  Identification 2°C to 8°C).  Logging (accessioning) Prothrombin time (PT) – stable for 24 hours.  Sorting (by department and type of processing) Partial thromboplastin time (PTT) – analyzed within 4 hours.  Evaluation (for specimen suitability to ensure accurate results) Centrifugation - A centrifuge is used to separate cells, plasma, or serum by spinning blood tubes at high speed. Reasons for Specimen Rejection; A specimen may be rejected due to the following reasons:  Stoppers must remain on before and during centrifugation to avoid: 1. Specimen is not identified properly. Contamination  Evaporation Aerosol formation pH changes  Tubes should be balanced in the centrifuge, placing tubes of the same size and volume opposite one another.  Centrifugation should not be repeated.  Plasma specimens (with anticoagulants) – centrifuge immediately.  Serum specimens – must be completely clotted (30-60 minutes at room temp) before centrifugation.  Stopper removal: Use face shield or splash shield for safety. Gauze/tissue to catch blood drops and prevent aerosol release. Pull stopper straight up and off to remove. Aliquot Preparation - Aliquot: A portion of a sample specimen taken for chemical analysis or testing.  Used when multiple tests are ordered on a single specimen.  Process: Transfer the specimen into one or more tubes using a disposable transfer pipette. Tubes must be labeled with the same information as the original specimen. Different anticoagulants should not be mixed in the same aliquot tube. The tube must be covered as soon as it is filled. OSHA Act (RA 11058) – Required Protective Equipment  Health workers are exposed to blood and infectious materials when processing specimens.  Healthcare institutions must provide protective equipment as per the Occupational Safety and Health Standards Act (RA 11058).  Protective equipment includes: Gloves Laboratory gowns/coats Masks