POCT and Urine drug sample collection PDF

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POCT and Urine drug sample collection notes...

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POCT and Urine drug sample collection  Definition of POCT  It stands for Point-of-Care-Testing  It is also known as Near Patient Testing, Bed-side testing, physicians office testing, extra-laboratory testing, decentralized testing, ancillary testing, and Alternate site testing  It is a laboratory testing at or near the patient bedside often by non-laboratory personnel  Locations where POCT can be performed:  Specialized areas of the hospital (ER, OR, ICU, Wards, Private Rooms)  Home health care  Physicians offices  Health Fairs (symposiums, medical drives)  Out-Patient clinics  Advantages of POCT  Decreased TAT  Decreased sample volume  Elimination of sample transport  Ease of use  Mobility  Increased interpersonal interaction between patient and healthcare personnel  Reduced medical cost  Improves clinical outcomes by decreasing patient’s discomfort and dissatisfaction  Disadvantages of POCT  Large numbers of operators causing diluted competency  Capturing documentation of QC and patient results  Charging and billing mechanisms in hospitals and other health institutions

 Samples used in POCT  Whole blood  Anticoagulated samples  Direct swabs from infected areas  Saliva  Urine  Non-invasive transcutaneous transdermal methods

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 Common POCT associated with lab dept

 Regulation of POCT  CLIA ’88:  POCT applies to anyone who performs testing on human specimens for the diagnosis, prevention or treatment of disease or health problems.  Everyone from the physician performing the most basic tests (e.g., dipstick urinalysis) to the technicians working in POL’s (Physician’s Office Laboratory)  Accrediting bodies for POCT: Commission of Laboratory Assessments (COLA), Joint Commission International (JCI), College of American Pathologists (CAP)  Implementing bodies: CDC (USA), DOH and FDA (PH)  Exemptions to CLIA ’88:  Facilities that perform testing for forensic purposes

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Research laboratories that do not report patient results These bodies are not regulated by the regulation bodies

 Complexity categories of lab tests by the FDA  Waived complexity  Simple procedures that are cleared for home use  Employ methodologies that are easy to perform, and the likelihood of erroneous results are negligible  Poses no reasonable harm to the patient if the test if performed incorrectly  Simple to perform and interpret  Require no special training or educational background  Requires only minimum QC  Examples of Waived complexity:  Blood glucose reagent strips  Tablet reagent urinalysis  Erythrocyte sedimentation rate (non-automated)  Fecal occult blood Hemoglobin  Ovulation tests  Spun hematocrit  Urine pregnancy tests  Non-waived complexity: Moderate complexity and high complexity  Moderate complexity  Are more difficult to perform  Require documentation of training in testing principles, instrument calibration, and QC  Personnel must have a minimum of a high school diploma or equivalent  Facilities performing moderate complexity tests are subject to proficiency testing and on-site inspections by accrediting bodies

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Persons performing POCT are required to demonstrate competency on a periodic basis  High complexity  Tests that require sophisticated instrumentation and a degree of interpretation by the testing personnel  Personnel performing high complexity tests must have formal education with a degree in laboratory science  Most tests performed in microbiology, immunology, immunohematology, and cytology are in this category  Provider-performed microscopy procedures (PPM)  Procedures that can be performed in conjunction with any waived test  Includes clinical microscopy procedures only  Can be performed only by physician’s assistant, nurse practitioner, midwives, physicians, and dentists during patient’s examination  Laboratories performing these test must meet the moderate complexity requirements for proficiency testing, patient test management, QC, and QA as required by the accrediting agency  Examples of PPM:  Fecal leukocyte examination  Fern test  Potassium hydroxide (KOH) preparation  Nasal smear for eosinophils  Pinworm examinations  Qualitative examinations of vaginal or cervical mucous  Qualitative semen analysis

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Urine sediment examination Wet mounts (vaginal, cervical, skin, or prostatic secretions)

 Quality assessment and control in POCT  Includes patient test management assessment  Includes methods of patient preparation, proper sample collection, sample identification, sample preservation, and accurate result reporting  The testing must have and follow written procedures for these methods so that specimen integrity and identification are maintained from the pretesting through the post testing process  QC assessment  QC must include records of the date, results, testing personnel, lot numbers, and expiration dates for reagents and controls  These must be retained for 2 years. It is recommended that records be reviewed daily, as well as monthly, in order to detect trends, shifts, unstable test systems, or operator difficulties  Proficiency training assessment  Moderate or high complexity testing must enrol in any approved proficiency testing program that involves three events per year, with five challenges per analyte in the survey material  All survey specimens are tested in the same manner as patient specimens  No communication with other laboratories is permitted

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In the PH: NEQAS (National External Quality Assessment) It is administered by the DOH on a yearly basis

 Personnel assessment  Includes education and training, continuing education, competency assessment, and performance appraisals  Each new employee must have documentation of training during orientation to the laboratory  This a checklist of procedure and must include date and initials of the person doing the training and of the employee being trained  Personnel file must include a certificate of the education level of each employee performing laboratory testing  Competency assessment  All POCT personnel who perform moderate and high complexity testing at 6 months and 1 year after initial training  After the first year, competency must be assessed and validated annually  Methods for assessing competency include direct observation, review of QC records and review of proficiency testing records, blind testing of specimens with known value, and written assessments  The standards may include evaluation of organizational and communication skills and attitude

 Quality assessment records  Patient records must be maintained for 2 years, 5 years for blood banking, and 10 years for pathology, cytology  Other records that must be kept include QC, reagent logs, proficiency testing, competency assessment, education and training, equipment maintenance, service calls, documentation of problems, complaints, and communications, inspection files, and certification records  Quality Control  To provide overall quality patient care  Performed to ensure that acceptable standards for accuracy and precision are being met during the process of specimen testing to provide reliable results  To verify that instrumentation is functioning properly and has been accurately calibrated, that reagents are stable and are reacting appropriately, and that testing is being performed correctly  Types of quality control:  External controls  Tested in the same manner as patient specimen  Used to verify test systems that use urine or blood samples  That external commercial controls are manufactured specimens with known values, and they are available in several strengths, such as anormal low, normal, and abnormal high ranges, or positive and

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negative depending on the test being performed The concentration of controls should be at medically significant levels and should be as much like the human specimen as possible At least two levels of assayed controls are used to evaluate daily performance of instruments Often required each time a new test kit is opened, or with each new lot number, and each new shipment of testing supplies

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Internal controls  Contained within the test system and are sometimes referred to as procedural controls  Commonly used in test kit systems, which verify that the test kit and any added reagents perform as expected  Many waived tests have internal procedural controls that indicate the test was performed correctly and that it was completed  Usually performed more frequently and are often performed with each test

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Electronic controls  Uses a mechanical or electronic specimen in place of a liquid QC specimen  Can be internal to the POCT device or an external

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component inserted into the POCT device Verify the functional ability of the POCT system Usually performed on a timed schedule, which can be daily, or every few hours, depending on the laboratory regulations. Many test systems use a combination of external and internal controls to verify the entire system is working properly

 Errors in POCT  Common errors in POCT that affect QA and QC

 Prevention of Common POCT errors  Correct patient identification  Proper sample collection  Proper storage of testing supplies  Always perform and document QC as required and confirm that QC results are within the expected range before any patient testing is performed  Sample application and test performance  Refer to the test procedure for correct interpretation of test results, confirmatory testing that may be required, and guidance for identification and communication of critical results  Results must be recorded in the permanent medical record, legible, and easily retrieved.  3 phases of lab testing using POCT  Pre-examination Phase:  Encompasses the test ordering process  Patient identification and patient preparation  Sample collection and handling, reagent storage  Preparing materials, equipment, and the test area  Examination Phase:  When the actual test is performed, and includes QC testing  Includes result interpretation  Post-examination phase  Involves recording and reporting results  Addressing critical values when indicated  Following through for confirmatory testing, and disposing of biohazard waste

  Procedure manual and package inserts  Contain information like sample collection and handling  Safety precautions regarding biological, chemical, electrical, and mechanical hazards  Instrument maintenance and calibration  Reagent storage requirements  Acceptable control ranges  Specimen requirements  Procedural steps  Interpretation of results and normal values and sources of errors  Troubleshooting assistance  Examples of POCT  POCT for glucose (glucometer)  To monitor persons with diabetes mellitus  To determine whether their diet and insulin dosage are maintaining an acceptable level of glucose  Normal values for blood glucose vary slightly among testing procedures and are higher when serum or plasma, instead of whole blood, is tested in the clinical laboratory  POCT must be performed on whole blood; however, most of the newer bedside glucometers report a plasma equivalent result  POCT glucose normal values are approximately 60-115 mg/dL in a fasting sample. Levels below 60 mg/dL are termed hypoglycemic, and increased levels are termed hyperglycemic  Principles:  Photometric  Electrochemical  Reflectance

Employ dry reagent technology using a special reagent strip

 POCT for transcutaneous bilirubin (bilirubinometer)  To detect and monitor increased levels of bilirubin (hyperbilirubinemia)  Screening for hemolytic disease of newborn (HDN) and premature birth, a variety of other risk factors for hyperbilirubinemia exist  Place it on the skin of the new born and it will measure the bilirubin levels  Principles:  Directs white light into the skin of the newborn and measures the intensity of the specific wavelength that is returned  TcB testing is approved for use on newborns of 27 to 42 weeks gestational age, 0 to 20 days postnatal age, and 950 to 4,995 g infant weight  The test is not affected by skin pigment and is appropriate for use on all races  Testing is not indicated for newborns who have received exchange transfusion  It is recommended that a dermal puncture be performed for closer monitoring of the bilirubin levels  POCT for hemoglobin  Determination of hemoglobin in the blood to monitor anemia  Principles:  Hgb measurement is determined photometrically using dry reagent system

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The reagents in the microcuvette lyse the RBC’s to release hemoglobin, which is converted to azide methemoglobin by sodium nitrite and sodium azide to produce color reaction A dual-wavelength photometer reads the absorbance of the reaction and corrects the hemoglobin value for lipemia and leukocyte

 POCT for urine  Principle: firm plastic strips to which are affixed several separate reagent areas for chemical, colorimetric, and reflectance tests.  Glucose – this test is based on a double sequential enzyme reaction  Bilirubin – this test is based on the coupling of bilirubin with diazotized dichloroaniline in a strongly acid medium. The color ranges through various shades of tan  Ketone – this test is based on the development of colors ranging from buff pink, for a negative reading, to purple when acetoacetic acid reacts with nitroprusside  Specific gravity – this test is based on the apparent pKa change of certain pretreated polyelectrolytes in relation to ionic concentration  Blood – this test is based on the peroxidase like activity of hemoglobin, which catalyzes the reaction of diisopropylbenzene dihydroperoxide and 3,3,’5,’5 – tetramethylbenzidine  pH – this test is based on the double indicator principle that gives a broad range of colors covering the entire urinary pH range. Colors

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range from orange through yellow and green to blue protein – this test is based on the protein-error-of-indicators principles urobilinogen – this test is based on a modified Ehrlich reaction, in which pdiethylaminobenzaldehayde in conjunction with a color enhancer reacts with urobilinogen in a strongly acid medium to produce a pink red color nitrite – this test depends upon the conversion of nitrate of nitrate to nitrite by the action of Gramnegative bacteria in the urine Leukocytes – granulocytic leukocytes contain esterases that catalyze the hydrolysis of the derivatized pyrrole amino acid ester to liberate 3-hydroxy-5-phenyl pyrrole. This pyrrole then reacts with a diazonium salt to produce a purple product

 POCT for fecal occult blood  This has the same principle as the urine reagent strip for blood, and it relies on the peroxidase activity of hemoglobin  It comes with its own collection materials and a test kit  POCT for pregnancy  This makes use of the principle of immunochromatography, and can be done without the supervision of a health care professional

   Urine sample collection for drug testing  Legal aspect of drug testing  R.A. 9165  Comprehensive dangerous drugs act of 2002  Safeguards the state and its citizens from dangerous drugs  Enhance the efficiency of the law against dangerous drugs  Re-integrate drug users back into society  Drug analyst: Licensed Physician, Dentist, Chemist, Medical Technologist, Nurse, Midwife, Veterinarian, or Pharmacist  R.A. 10586  Anti-drunk and drugged driving act of 2013 

These 2 republic acts are used together and are used to enforce drug testing in the Philippines

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Mandatory drug testing:  Applicant for Driver’s license (new)  Application for firearm license  Officers and members of the military, police and other law enforcement agencies  All persons who by nature of their profession carry firearms (e.g. security guards)  Any person arrested for violation of RA 9165  All candidates for public office whether appointed or elected

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Drug test results:

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Valid for 1 year from the date of issue May be used for other purposes other than the aforementioned (e.g., employment) Shall be signed by the analyst and head of laboratory (usually a pathologist) Confidential Positive screening results must be confirmed for it to be valid in court

Drug testing kit validation:  Responsibility of DOH  Registered through the FDA  Validated by NRL (National Reference Laboratory): East Avenue Medical Center

 Components of Drug testing laboratory  People:  Head of the Laboratory (HOL) usually a pathologist  Analyst  Authorized specimen collector (ASC)  Others: clerks, secretary, Lab aide, other admin personnel  Specimen collection  Collection site  Place where the specimen is collected  Can be a permanent or remote site (laboratory or the analyst can go to another area for a remote collection)  Must have clean surfaces for handling specimen and completing paperwork  Secured temporary storage capability to maintain a specimen until tests

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Able to provide patient privacy appropriate to the specimen being collected Controlled and secured are for supplies and records Posters or information bulletin with detailed descriptions of the proper specimen collection process should be available Source of water for handwashing must be external to the toilet facility and coloring agent must be used

Collection supplies  Specimen containers  Tamper evident seals  Labels, water proof pens  Gloves  Leak – resistant plastic bags (ziplock)  Coloring/ bluing agent  Thermometer/temperature strip  Documents (CCF, MFR logbook)  Shipping containers

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Type of specimen and reason for test

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Type of specimen and collection device

 Type of specimen  Urine  Least expensive, most popular  Easy to do  Standardized procedure  Detects drug use within the week  Abstaining can produce negative reactions  Establish specimen validity tests  Saliva:  Uncommon method  Easy to administer  Short detection time  No reference standards  No confirmatory testing available  Blood:  Most expensive method  Most accurate  Least common method  Short detection time  Procedure not established and not standardized  Sweat:  Requires wearing the patch for 1 to 2 weeks  Uncommon method  No reference standards developed yet  Surface contamination can cause false positive results  Can detect for extended period of time  Hair:  Expensive and tedious  Twice more sensitive than urine test  Do not detect recent use  Detects chronic substance abuse  Requires 1.5x1.5 cm hair clump or 80 to 120 hair strands

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Not affected by drug abstinence Can determine temporal pattern Longest detection and retention time (1 year)

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 Quantity of Specimen

 Urine collection  Observed collection: done presence of the ASC  Unobserved collection:  In the absence of an ASC  Submitted samples  Subject to validity testing

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 Conditions for unobserved samples  Donor is physically unable to the laboratory or designated collection site  Involved in a crime scene  Involved in post-accident situation  Critically ill  Types of specimen collection  Single specimen collection – specimen is entirely placed in a single 60mL bottle  Split specimen collection – specimen is collected at the same time, but placed in 2 separate containers at least 30 mL each

 Ways of tampering urine specimen  Dilution  Adulteration – chemicals or substances are added to the sample in the hope of gaining a negative result  Substitution – when the donor has a negative urine specimen already on ...