Quality in point-of-care testing: taking POC to the next level

  • Published on

  • View

  • Download

Embed Size (px)


<ul><li><p>Accred Qual Assur (2006) 11: 273277DOI 10.1007/s00769-006-0130-z GENERAL PAPER</p><p>Quality in point-of-care testing: taking POCto the next level</p><p>James H. Nichols</p><p>Received: 28 November 2005Accepted: 27 February 2006Published online: 8 April 2006C Springer-Verlag 2006</p><p>Presented at the 10th Conference Quality inthe Spotlight, March 2005, Antwerp,Belgium.</p><p>J. H. Nichols ()Tufts University, School of Medicine,Director, Clinical Chemistry BaystateHealth System,759 Chestnut Street, Springfield,MA, 01199, USAe-mail: james.nichols@bhs.orgTel.: +1-413-794-1206Fax: +1-413-794-5893</p><p>Abstract Point-of-care testing(POCT) is a complex system withmany opportunities for error.Delivering quality POCT requiresmultidisciplinary coordination and anunderstanding of the preanalytic,analytic, and postanalytic processesthat are necessary to deliver a testresult and take clinical action. Mosterrors in laboratory testing occur inthe pre and postanalytical phases andmany mistakes that are referred to aslab error are actually due to poorcommunication, actions by othersinvolved in the testing process, orpoorly designed processes outside thelaboratorys control. POCT requiressignificant operator interaction withanalysis and documentation ofcalibration and quality control, unlikeother medical devices. Clinicians</p><p>often interpret POCT as equivalent tocore laboratory testing, only faster,and mistakenly utilize the resultsinterchangeably despite thedifferences in test methodologies.Taking quality of POCT to the nextlevel involves looking beyond theanalytical phase and integration ofPOCT into the entire pathway ofpatient care to understand how POCTrelates to medical decision-making atspecific points during the patientscare. A systematic review of theliterature by the National Academy ofClinical Biochemistry is currentlybeing conducted to draft guidelinesfor best practice that link the use ofPOCT to improved patient outcomes.</p><p>Keywords Point of care testing .Quality . Medical errors</p><p>Introduction</p><p>Quality is defined as a peculiar and essential character (na-ture), an inherent feature (property), or a degree of excel-lence (grade) [1]. Point-of-care testing (POCT) is testingperformed at or near the site where clinical care is deliv-ered. Quality in POCT refers to testing that (1) is safe andreliable, (2) uses appropriate technology to meet clinicalneeds, (3) can be trusted for medical management, and (4)is defensible legal documentation in the patients record.Most importantly, the reputation of the laboratory dependson the quality of the test results.</p><p>There has been a number of quality issues with POCTraised in the literature. Nursing home patients in three stateshave been diagnosed with hepatitis B infections transmittedin association with blood glucose monitoring from nursingstaff who failed to change gloves or clean contaminateddevices between patients [2]. State inspectors of POCT in</p><p>Ohio and Colorado found significant quality problems inover 50% of the physician office practices inspected [3]. Onfollow-up inspection of 2.5% of physician offices in eightstates, inspectors found: 32% did not perform quality control as required 20% cut occult blood cards and urine dipsticks in half to</p><p>save money 19% had personnel who were neither trained nor evalu-</p><p>ated 16% failed to follow manufacturers instructions 9% did not follow manufacturers storage and handling</p><p>instructions 7% did not perform calibration as required by manufac-</p><p>turer instructions 6% were using expired reagents and test kits [3, 4]</p><p>The need for staff education and implementation of goodlaboratory practices was reinforced by this data [4].</p></li><li><p>274</p><p>POCT devices may seem simple, but POCT is a com-plex system. In the central laboratory there is one site withlimited instrumentation and staff to perform the bulk oftesting. The staff is trained in laboratory skills and focusedon operating the same equipment every day. In contrast,POCT has dozens of sites with hundreds of devices andthousands of operators. The staff is clinically focused onpatient care and not on maintaining equipment and the staffalso does not have laboratory training and are not attunedto detecting preanalytic and analytic sources of error.</p><p>With so many operators and devices to supervise, it isnot surprising that medical errors from POCT are a majorconcern. In the U.S., medical errors have become a primaryhealth care issue. A 2002 Commonwealth fund report esti-mated that 22.8 million people have experienced a medicalerror either personally or through at least one family mem-ber [5]. This data reinforces the 1999 Institute of Medicinereport titled, To Err is Human [6]. It is estimated thatmedical errors cost the United States $1729 billion dol-lars annually [7]. The US agency for Healthcare Researchand Quality (AHRQ) estimate that medical errors are theeighth leading cause of death in U.S. today. Medical errorfatalities are higher than annual death rates due to mo-tor vehicle accidents (43,458), cancer (42,297), and AIDS(16,516) [7].</p><p>Laboratory errors are typically thought to be patient, tube,or aliquot mixups. However, other more insidious errorsshould be considered. Overutilization of testing or fishingis when clinicians order every test available in the hopes offinding something abnormal. Other errors can occur fromthe inappropriate use of testing, for instance the use of ascreening test for diagnosis, or picking the wrong method ortest for the patient symptoms. There are misunderstandingerrors as well, where point-of-care testing is assumed to beequivalent to the laboratory test. Errors can also occur fromdelays in ordering a test, receipt of the results, or in clinicalaction.</p><p>A minireview of the literature found the majority oferrors in laboratory testing occur in the pre and postanalyt-ical phases [8]. Many mistakes are referred to as lab error,but actually are due to poor communication, actions byothers involved in the testing process, or poorly designedprocesses that are outside of the laboratorys control.Medical errors can occur in prevention, diagnosis, and drugtreatment. Among the errors in diagnosis that are related tothe laboratory, 50% were failure to use the indicated tests,32% were failure to act on the results of tests, and 55%involved avoidable delays in diagnosis [9]. There is a needfor quality laboratory testing given that laboratory testinginfluences &gt;70% of all medical decisions and more than7 billion lab tests are conducted in the U.S. annually [10].</p><p>POCT devices differ from other medical devices, likethermometers, scales, sphygmomanometers (blood pres-sure devices), or pulse oximeters. POCT devices appear tobe simple, but often require significant operator interactionincluding calibration and performance of quality control.Clinicians place a thermometer in a persons mouth, get anumber and trust that the number is correct without havingto calibrate or perform quality control or other tests on the</p><p>thermometer. Clinicians tend to interpret POCT as equiv-alent and interchangeable with core laboratory tests, onlyfaster, without consideration for the method limitations.Additionally, more than 50% of POCT is manual, visuallyinterpreted colorimetric tests that require additional oper-ator considerations. It is not surprising that errors occurin such a complex system with so many steps and activethought processes that are required to attain a result. Whenerrors do occur, it is often easier to blame a person fornot following policy rather than looking to the system as acause for that error.</p><p>Achieving quality</p><p>Quality assumes an understanding of all of the processesthat lead to the final product, the test result, and how thetest will be used to manage patient care. But how are weto guarantee consistency of process and quality of resultswith so many sites, devices, and people to manage, andwhen performing a test requires so many steps that inter-rupt patient care responsibilities? We need to take qualitybeyond the laboratory perspective and the results of liq-uid quality control solutions. Why was the test ordered inthe first place? How does the staff interact with the deviceand how will the result be used in the continuing care ofthe patient? Quality requires the integration of POCT intopatient care and a fundamental understanding and controlover preanalytic, analytic, and postanalytic variables.</p><p>Automation can simplify the complexity of the steps re-quired to perform testing with POCT devices. Automationcan also assist with regulatory compliance, performanceimprovement, and enhanced communication. Data man-agement features on newer POCT devices prompt the op-erator for the information required for compliance, likeoperator and patient identification, and also prompt theoperator to perform the test in the appropriate sequenceof steps, reducing analytic variability and the possibility oferror. Data management features ensure quality by locking-out operators who are not trained on operating the deviceby requiring a valid operator identification number to beentered before testing can be started. Data managementlock-outs also require quality control to be performed pe-riodically and prevent patient testing if quality control hasnot been done or the controls fall outside of an acceptabletarget range. POCT data management thus reduces the riskof wrong results from common operational errors.</p><p>At Baystate Health System, we utilize both blood gas andglucose devices with data management features. However,we have noted a large number of data entry errors where theoperator entered the incorrect patient identification numberduring testing. As data is transferred from the POCT de-vices, incorrect patient identification numbers cause testresults to be held in our laboratory computer system be-cause the results cannot be matched to an active patient, oreven worse, an incorrect identification number has the pos-sibility of transferring test results to a wrong patient withthe potential for inappropriate medical action. Our initialgoal of reducing identification errors was less than 5%. This</p></li><li><p>275</p><p>was lowered 3 years ago to less than 2%. However, at ourlast accreditation inspection, the inspector recommendedzero-tolerance. With more than 400,000 glucose tests andover 100,000 blood gas tests annually, a tolerance of 2%could lead to 10,000 laboratory errors where any one ofthese has the potential of leading to inappropriate medi-cal action. Our immediate response to the inspection waspunitive action on the operators. We implemented a three-strike rule where operators were automatically locked outof testing after the third identification error. This loweredour error rates, but was still unable to achieve the goal ofzero errors [11].</p><p>In order to determine the source of our POCT identifica-tion errors, our intensive care unit conducted a failure modeand error analysis (FMEA). The FMEA analysis tracks thePOCT process to determine all potential sources for theidentification error and seeks methods to control the rootcause of the error and the effects of errors in all stages,preanalytic, analytic, and postanalytic, of the testing pro-cess. We found that identification errors are due to multipleissues. Our patients have a long identification number (ninedigits) and it is easy to transpose numbers when manuallyentering nine digits. Some of our point-of-care devices can-not accept leading zeros, so the staff is forced to place thezero somewhere else in the identification, which changedthe identification number. Patient wristbands were not leg-ible because the card plates identifying patients wore outover time and the numbers could not be transferred to thewristband. Finally, our three-strike rule was causing oper-ators to be locked out from testing across an entire unit,which led to operators sharing identification numbers toaccess the POCT devices.</p><p>Bar-coding was seen as an optimum solution [11]. In the-ory, bar-coding should have been very easy to implement.In practice, bar-coding was one of the more challengingprojects that we have implemented in our institution. Wefound that POCT devices only read specific barcode lan-guages, and many devices do not share the same language.Bar-coded wristbands vary in durability depending on howthey are printed. The ink is not permanent and can be read-ily washed off the wristbands. Thermal printing is moredurable, but the printers are very expensive. POCT devicesdo not force operators to utilize bar codes and operatorscan continue to utilize manual entry of patient identifica-tion numbers. We tried to engineer around manual entry byadding special characters or digits to the bar-coded identi-fication. However, these features lengthen the barcode andincrease the failure rates of scanning the barcode on thefirst attempt. We noted additional difficulties in areas likethe operating room, where wristbands were not utilized oron neonates, where the wristbands did not fit.</p><p>During implementation of patient bar-coding, many op-erators continued to manually enter patient identificationsdue to the scanners failing to read the patient wristbands.Operators complained that our blood-gas analyzers failedmore frequently than our glucose meters. We conducted atrial of barcode scanning where we varied the distance, theangle, the age, and the lighting of the barcode during scan-ning. We found the optimal depth of field for scanning</p><p>with the glucose meter differed from the blood-gas analyz-ers. While 6 and positioning the scanner perpendicular tothe barcode was optimal for both devices, the rate of suc-cessful scanning fell as the distance away from 6 or anglefrom perpendicular increased and the pattern was uniquefor each device [12]. Operators had to be trained in properscanning with each device, and we could not assume thatthe skill could be naturally picked up. Once operators weretrained in proper scanning, we began to achieve zero errorrates on our monthly reports [12].</p><p>Resolving our patient identification problem required theimplementation of automation and a complete understand-ing of the system, preanalytic, analytic, and postanalytic.Blaming a person for the error was not as successful aschanging the overall system. Once we changed the systemfrom manual entry to bar-coded data entry, we uncoveredother reasons for identification errors that have become newtopics for our quality improvement efforts. Errors continueto occur when patients are bar-coded with the wrong iden-tification number, or the staff fails to remove expired iden-tification numbers when patients are readmitted [11]. Fromthe American Association for Clinical Chemistry POCTlistserv (www.aacc.org), institutions trialling bar codingvary in success from </p></li><li><p>276</p><p>the patients pathway of care. The development of practiceguidelines and clinical protocols can assist clinicians withthese decisions, and standardize the utilization of testing bylinking the need for a test to the optimal type of test and themedical management required from the test result in theongoing care of a particular di...</p></li></ul>