point of care testing

Clin Lab Med 27 (2007) 893–908

Point of Care Testing

James H. Nichols, PhD, DABCC, FACBTufts University School of Medicine, Baystate Medical Center, Department of Pathology,

759 Chestnut Street, Springfield, MA 01199, USA

Point of care testing (POCT) is laboratory diagnostic testing performedat or near the site where clinical care is delivered. POCT provides the advan-tage of rapid test results with the potential for faster patient treatment. Withincreasing pressure on physicians to see more patients and spend less timewith each patient, POCT has become a popular means of meeting the de-mands for faster laboratory testing. POCT devices use small amounts of un-processed specimen, so less blood is required, allowing the use of fingersticksover the risk of phlebotomy. A wide menu of analytes is available, includingblood gas, electrolytes, pregnancy, cardiac, and infectious disease testing(Box 1). The convenience of POCT has led to broad adoption of POCTinto clinical practice over the past 20 years. Current estimates indicatethat POCT encompasses nearly one third of the in vitro diagnostic testingmarket and is growing at a rate of 9%, with annual sales of $7 billion world-wide [1,2].

Federal regulations have facilitated the use of simple POCT devices. Al-though the federal Clinical Laboratory Improvement Amendments of 1988(CLIA’88) set minimum standards for validation and quality control of lab-oratory tests, a separate category of simple testing called ‘‘waived’’ tests wasdeveloped. CLIA ‘‘waived’’ tests are examinations or procedures that ‘‘arecleared by the United States Food and Drug Administration (FDA) forhome use; employ methodologies that are so simple and accurate as to ren-der the likelihood of erroneous results negligible; or pose no reasonable riskof harm to the patient if the test is performed incorrectly’’ [3]. Although lab-oratories adopting nonwaived testing must perform initial and ongoing de-vice evaluation, document operator training and competency, subscribe toproficiency testing, and develop a quality assurance program, includingdaily performance of quality control, laboratories adopting waived testsonly need to enroll in the CLIA program, pay a biennial certification fee,

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and follow manufacturer’s test instructions. Because of these simple regula-tory requirements, the number of CLIA waived tests has grown from 8 inthe original CLIA ’88 regulations to more than 40 tests today. Additionally,the number of certificate of waiver (COW) laboratories has increased from

Box 1. Current clinical laboratory improvement amendmentswaived category tests available

Diabetes testingGlucoseKetoneHemoglobin A1c

HemoglobinReproductive testing

Human chorionic gonadotropin (pregnancy)Luteinizing hormone and Fern Test (ovulation)Follicle-stimulating hormone (menopause)

Renal functionUrine dipstickMicroalbumin

Infectious diseaseStreptococcusHIVHelicobacter pyloriInfluenza A and BMononucleosisRespiratory syncytial virusTrichomonaspH and amines (bacterial vaginosis)

Occult bloodDrugs of abuse testingTherapeutic drug monitoring (lithium)Lipids

CholesterolHigh-density lipoproteinLow-density lipoproteinTriglycerides

Brain natriuretic peptideLiver function

Aspartate aminotransferaseAlanine aminotransferase

Coagulation (prothrombin time/international normalized ratio)Tumor markers (bladder tumor-associated antigen)

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20% to 58% of the nearly 180,000 CLIA-certified laboratories [4]. Most ofthese are physician office practices.

This rapid increase in the use of POCT has led to concern about the qual-ity and risks of POCT. Home blood glucose testing devices represent thelargest number of complaints filed with the FDA for any medical device,with more than 3200 incidents, including 16 deaths [5,6]. Poorly maintainedurinometers and blood gas analyzers that are carried between patient roomscan act as infectious reservoirs for nosocomial and antibiotic-resistant or-ganisms [7,8], and blood glucose testing devices have been linked to trans-mission of hepatitis B infection among patients at nursing homes inCalifornia, Mississippi, and North Carolina [9]. A 2001 state survey ofCOW laboratories found that 21% of laboratories were not performingquality control as required, 12% failed to keep manufacturer’s package in-sert, 21% failed to check the package insert for changes, 18% failed to re-port results in units or as recommended in package insert, 6% were usingexpired reagents, and 3% were not storing the reagents as recommended [4].

Although POCT devices may seem simple, these devices are not innocu-ous. Consumers and operators of these devices need to be aware of the po-tential risks and take steps to ensure appropriate test quality. This articlereviews several strategies to enhance the quality and integration of POCTinto patient care.

Point of care testing organization

Despite the illusion of simplicity, in practice, POCT devices can be af-fected by several factors beyond the analytic process, including the environ-ment and the operator. POCT presents challenges in managing thepreanalytic, analytic, and postanalytic processes similar to centralized labo-ratory testing. Systematic reviews of the literature find that most laboratoryerrors occur in the preanalytic and postanalytic phases of the testing pro-cess, outside of the walls of the traditional laboratory [10]. This is the settingwhere POCT is conducted, and there is ample opportunity for error.

Unlike the traditional laboratory where the bulk of testing is conductedon a few analyzers by a core group of skilled and trained technicians, POCTis conducted by a variety of clinical staff on multiple devices in many loca-tions. An average hospital may have thousands of operators conducted test-ing with hundreds of devices at more than 30 to 50 locations (Box 2). Thisstaff is focused on patient care and not on the nuances of instrument calibra-tion and quality control. In fact, most clinical staff involved in POCT arenot trained in laboratory processes and do not know what quality controlis or even why controls are important. Getting all staff to perform POCTthe same way every time that the test is conducted presents a logistical chal-lenge. Managing the volume of paperwork from training, test results, bill-ing, quality control records, and other documentation can become

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overwhelming. Laboratory professionals provide an important role as a re-source of technical information and can assist in organizing a POCT pro-gram, establishing policies, standardizing training, and supporting theoverall quality management of POCT whether conducted in a single-physi-cian office or in a large health system.

The ‘‘laboratory director’’ on the CLIA certificate plays a key role inmanaging POCT. Under CLIA’88, every site with a separate mailing ad-dress must have a CLIA certificate if it is performing testing for patientcare. A laboratory director is responsible for all testing performed undera CLIA certificate. Although some activities, like the daily review of qualitycontrol, can be delegated to other qualified staff, the CLIA laboratory direc-tor is ultimately responsible for all testing and quality of test results pro-duced under his/her name. The consequences for noncompliance withfederal CLIA regulations can result in limitations of a site’s ability to per-form testing and can sanction the laboratory director on the CLIA certifi-cate, preventing that individual’s ability to bill Medicare for laboratoryservices for periods of up to 2 years or more.

The laboratory director must be a physician, pathologist, or doctoral-level laboratory scientist with laboratory experience and training; however,the experience and training are not required for sites with a COW. Thus,a doctor in a physician’s office practice can act as the laboratory directorfor that office if the site only performs simple waived testing. For more com-plex testing, the laboratory director must be a pathologist or a doctor withsome laboratory training and experience. The site can contract for externalconsulting with a qualified laboratory director, but federal and state regula-tions limit the number of CLIA certificates to three to five sites for any in-dividual laboratory director. This ensures that the laboratory director hastime to spend at each site and is actively participating in and aware of thetesting conducted under his/her name.

Box 2. Test operational features

Laboratory testingOne siteLimited instruments perform bulk of analysesLimited staff with focus on sample analysisStaff with laboratory training and experience

POCTMultiple sitesMultiple devicesMultiple staff with focus on patient careStaff with clinical training, not laboratory education


Although the limited testing performed in a small physician office gener-ally can be managed between the laboratory director and one or two staffmembers, management of POCT in larger institutions and hospitals requiresa team of staff to coordinate the testing. With multiple staff, devices, and lo-cations, the volume of testing in hospitals requires a more formal POCTprogram organization (Fig. 1). One CLIA certificate can cover all POCTconducted within the hospital, with the laboratory director coordinatingthe testing through the assistance of a dedicated staff member (POCTcoordinator) or team (POCT team led by a POCT coordinator). ThePOCT coordinator or team handles the routine technical, training, andtroubleshooting tasks of ensuring that the POCT devices are functioningproperly and that the staff at each site is trained and competent to be per-forming the tests. This team also is responsible for ensuring site compliancewith institutional policies and overall institutional conformity with federaland state regulations. The laboratory director can delegate these tasks,but should ensure control over the entire program by setting and reviewingpolicies and procedures, as well as assisting in the clinical interpretation ofPOCT results and consulting with physicians on unusual cases when the testresult does not match the clinical symptoms. Together, the POCT team, ledby the laboratory director and supervised by the POCT coordinator, acts asan administrative group to orchestrate the POCT processes that will meetpatient and physician needs (see Fig. 1).

Standardization

POCT is not just a faster laboratory test. POCT devices are differentmethodologies from core laboratory methods, and the test limitations and

LaboratoryDirector

POCTCoordinator

POCTCommittee

Unit NursePOCT Contact

ClinicStaff Contact

PhysicianMember

NursingMember

PurchasingMember

AdministrationMember

Fig. 1. Organization chart for POCT management in a hospital.

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interferences can vary significantly. Glucose meters, for instance, can gener-ate widely disparate results compared with core laboratory methods in pa-tients who have ketoacidosis. This effect is noted in meters from manymanufacturers and is more than a matrix difference (ie, capillary versus ve-nous sample). Most importantly, the differences are noted in the same spec-imen and tend to resolve as the patient is hydrated and ketoacidosis declines.Transcutaneous icterus devices generate comparable estimates to total se-rum bilirubin, except when bilirubin is elevated (O12 mg/dL). These icterusdevices are contraindicated in premature infants, babies undergoing photo-therapy, and certain ethnic groups with dark skin. Conversely, bilirubin andglucose analysis using serum or plasma in a core laboratory do not havethese types of issues. Therefore, implementation of POCT devices must con-sider the test limitations, and the quality assurance program should ensurethat the test is not used in patient populations that are contraindicated orknown to generate misleading results.

These cases illustrate the need for evaluating a POCT device in the spe-cific patient populations in which the test is intended to be used. If limita-tions and differences between POCT and core laboratory methods areknown before use in patient care, steps can be taken to prevent the misinter-pretation of test results. For instance, prior knowledge of glucose meter is-sues in patients who have ketoacidosis would raise concern about the use ofa glucose meter to screen patients in the emergency room. During triage,routine screening of all patients could generate misleading results in patientswho have ketoacidosis. A physician should examine emergency patients forsymptoms of ketoacidosis before testing with a glucose meter. By examiningpatients before testing, staff can ensure that this problem is prevented. Analternative practice could screen patients for positive urine ketones beforethe use of a glucose meter. Thus, implementation of POCT requires theselection of devices that match patient care needs, as well as appropriatedeployment to ensure quality results and prevent known limitations.

Standardization of POCT technologies can help to improve quality inmultiple ways. Use of a single manufacturer or device may allow for sharingof one policy and procedure across multiple sites. Training is simplified, be-cause one common checklist can be used. Testing also is more consistent,because staff who float between sites will not have to remember the opera-tion of the same test from different manufacturers, each likely to have dif-ferent testing protocols. Most importantly, test interferences and resultdifferences are minimized by limiting the number of unique devices in use.In summary, standardizing to a single POCT technology (eg, a single glu-cose manufacturer or single pregnancy test) is the most important stepthat an organization can take to improve quality. By preventing sitesfrom randomly implementing POCT devices and narrowing each test toa single device/manufacturer, testing will be uniform, and patients will expe-rience the same test as they move from one site to another within an insti-tution or health system. This ‘‘continuity of care’’ is a key goal in health


care that is being stressed by the Joint Commission and the College ofAmerican Pathologists (CAP) in their hospital and laboratoryaccreditations.

A POCT committee consisting of multidisciplinary membership can helpto facilitate the standardization of POCT technologies in an institution byproviding a forum for review of new test requests, establishment of sys-tem-wide policies, and discussion of POCT issues (see Fig. 1). Committeescomposed of laboratory, physician, and nursing members provide balanceand viewpoints from different perspectives. The laboratory is knowledgeableabout test limitations and quality assurance/control processes. Nurses con-duct the testing and have operational concerns to bring to the table. Physi-cians use the POCT results in patient management and will have issuesregarding clinical interpretation of POCT. Additional members are useful,depending on the issues being debated, and could include purchasing, ad-ministration/budgeting, pharmacy, and hospital quality improvement. Forexample, the POCT committee is important to resolving conflicts involvingPOCT and depersonalizes the responsibility of decision-making from a singleindividual to an entire committee. Selection of a device for hospital use mayinvolve evaluation of the device and review of the data by the POCT com-mittee for approval/disapproval or limitation of use. The POCT committeecould review the data for a transcutaneous icterus device and limit its use tothe well baby nursery, because this device is known to not perform well inpremature infants (ie, preventing its use in the neonatal ICU). This wouldbe a committee decision to set a hospital policy of where and how the devicewould be used. Physicians who are not comfortable with this policy couldaddress the committee, rather than directing comments to any single indi-vidual. Therefore, the POCT committee assists in management by offeringa forum for discussion of issues and establishes consensus-driven decisionmaking.

Point of care testing and the environment

Unlike laboratory testing in the well-controlled and monitored environ-ment of a core laboratory, POCT takes place in a variety of settings andconditions. Many POCT kits contain reagents that are sensitive to heat,cold, light, and moisture. Consumers need to be aware that storage anduse conditions can affect the quality of results. In most cases, however, com-promised reagents still provide results, although perhaps not always accu-rate ones.

Care must be taken in shipping so that tests kits do not freeze or becomeoverheated. Pregnancy tests contain protein antibodies that can be dena-tured at high and low temperatures. Freezing during ground transportationin the winter months and cooking the reagents during summer months canaffect test performance. Blood gas cartridges contain liquid reagents that arecalibrated to known levels of gases. Extremes of environment, freezing and

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heating, can alter tonometered blood gas levels. On arrival in the clinic orhospital, test kits should be checked for appropriate function by analyzingspecimens with known values, such as quality control solutions or previ-ously analyzed patient samples.

Tests should be stored as recommended by the manufacturer under tem-perature- and humidity-controlled conditions. Urine dipsticks containchemicals that are degraded by light, heat, and humidity. These tests shouldbe stored in dry cabinets and not near sinks, patient restrooms, or othersources of moisture. Caps should be replaced and tightly covered after useto prevent humidity in the air from contacting the dipsticks. Occult bloodcards also are sensitive to light, heat, and humidity. These cards shouldbe stored in a dark, dry cabinet away from windows, radiators, and othersources of light and heat.

The environment also can affect POCT analysis, and staff should beaware of potential environmental factors that can impact test results. Fluo-rescent lighting, for instance, can affect color discrimination on urine dip-sticks, so development is recommended under bright incandescent lightingconditions. Visiting nurses who perform health care in patient homes oftenuse POCT devices. Care needs to be taken to protect the tests from the en-vironment. Tests or kits left in the trunk of a car or back of an ambulancecan freeze in the winter and cook in the summer months. Devices like glu-cose meters have internal checks within the device that prevent analysis ifthe temperature or humidity is too low or high. These checks, however,only monitor the electronics of the device and not the chemistry of thetest strips. Staff needs to be aware that the test strip and the device combineto form a result, and quality requires managing the exposure of the strip anddevice to environmental extremes. Blood gas devices are calibrated at sealevel. Performance of POCT at higher elevations, in helicopters, or in pres-surized airline cabins can affect the calibration and bias patient results. Themanufacturer should be consulted if blood gas analysis is going to be con-ducted in different locations or during mobile transport. Thus, a varietyof environmental factors that can affect POCT results should be managedto ensure quality test results.

The point of care testing operator

Analytical technique can affect the quality of POCT results. Althoughmost core laboratory instrumentation is highly automated and nearly inde-pendent of operator technique, POCT uses predominantly simple devices ormanual, visually interpreted colorimetric tests that are reliant on consistenttechnique. Even when following manufacturer instructions, problems canarise. Samples can be collected in the wrong anticoagulant, and delays inanalysis can lead to clots. Bubbles can be injected into analyzers, and bloodgas specimens can be exposed to air. Too much or too little sample can beapplied. Tests can be overtimed or undertimed. Staff can program devices


with the wrong lot-specific calibration codes. Although some POCT deviceshave internal control mechanisms to detect bubbles, clots, sample flow orvolume, and other common operator variables, these issues are primarilyunintentional and not recognized by staff during the testing process. Thisis a prime opportunity for staff education and creates a continued needfor maintaining staff competency on a periodic, or at least annual, basis.The large number of staff involved in POCT creates an even greater chancefor variability.

Manual and labor-intensive methodologies do not prompt staff from onestep to the next step, allowing for procedural errors and the opportunity totake short-cuts. Although laboratory professionals consider POCT devicesto include glucose, pregnancy, rapid strep, and other ‘‘diagnostic’’ tests,physicians and clinical staff are more familiar with medical devices, suchas scales and thermometers, that they consider POCT devices. The majordifferences among scales, thermometers, and glucose meters are that staffhas fewer steps and decision making involved with medical devices. The pa-tient stands on a scale, and the physician assumes that the device gives thecorrect weight. Staff may need to zero the scale periodically, but the physi-cian does not need to check expiration dates, monitor refrigerator tempera-tures, check lot numbers and calibration codes, analyze quality controlspecimens, determine whether quality control is successful, and troubleshootif quality control is not successful before obtaining a patient result. Theseseveral actions may seem inconsequential to a laboratory-trained individual,but are not routine at all for a clinician. These activities actually remove theclinician from his/her primary responsibility of patient care.

Automation can reduce the potential for error. Devices that decrease thenumber of steps required to obtain a test result, prompt operators, or reducethe staff decision-making process can reduce the potential for mistakes.Newer POCT devices are computerized with electronic data capture thatis capable of storing and transmitting results automatically to laboratoryand hospital information systems. These devices can capture the date,time, operator identification, patient identification, meter serial number,and test lot number/expiration dates with every patient test result and storeit in relation to the quality control performed on that device. Computerizeddevices can store a list of trained operators and request operator identifica-tion before allowing patient testing. If the identified operator is not on theauthorized list, the device prevents untrained individuals from performingpatient testing. Computerized devices also can require the analysis of twolevels of quality control every 24 hours. The device compares quality controlresults against the expected target ranges and can interpret whether controlresults are successful or unsuccessful. These features assist with regulatorycompliance by ensuring result documentation, performance of testing bytrained operators, and daily quality control; however, these features alsohelp staff to perform testing by prompting staff with each step of the analysisand by interpreting quality control results and taking appropriate action

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(allowing patient testing if successful and lock-up preventing patient testingand requiring repeat control analysis if unsuccessful).

Automation of POCT devices also can help with data entry. Manual in-put of multiple numbers for operator and patient identification presents anopportunity for transcriptional errors. Computerized POCT devices havebarcode readers that allow automated reading of operator barcodes and pa-tient barcoded wristbands. Barcoded data significantly reduce manual dataentry errors in institutions implementing these systems [11]. Barcodes alsohave the potential to assist with positive patient identification if the devicecan provide a confirmation of the patient’s name after scanning the identi-fication number; however, few current POCT devices have the memory orwireless connectivity to offer this advanced positive patient identification,and this certainly is a feature to watch for in the next generation of devices.

Training with ongoing competency checks is fundamental to ensuringquality test results. Staff operators of POCT devices should receive trainingspecific to the device being used. Familiarization of test technologies in nurs-ing or medical school does not substitute for in-depth training on themethod intended to be used for patient care. A CAP Q-Probes survey ofhospital blood glucose programs that demonstrated the most significantlevels of continued improvement over time focused on operator training[12]. These programs used standardized training materials, such as video-tapes, as part of the training and repeated training and review of perfor-mance at scheduled intervals. These programs also compared resultsregularly between point of care devices and central clinical laboratory test-ing and used computerized data capture in POCT devices to manage controland patient data [12].

In summary, POCT is dependent upon operator technique. Training andongoing verification of competency are important. Current CAP and JointCommission regulations require ongoing competency by observation oftechnique, written examination, analysis of quality control or specimenswith known values, demonstration of maintenance, recording of test results,and evaluation of problem-solving skills. These skills should be checkedinitially, at 6 months, and annually after training. Use of devices withautomated data management features can assist staff in appropriate testperformance and help with regulatory compliance.

Integration and communication

POCT is not an isolated process and should be integrated with patientcare pathways. The laboratory is blamed often for delays in patient manage-ment, particularly in the emergency room, preoperative and proceduralareas of the hospital, and outpatient settings that are remote from a corelaboratory. POCT is seen as one means of obtaining faster test results andreducing patient bottlenecks in the system. Unfortunately, just providing


a faster test result does not guarantee improved patient outcomes. Manage-ment pathways also must change to better use the faster result. Considerpoint of care glucose testing where the physician has created a standing or-der for testing every hour but then leaves the nursing unit to attend to otherpatients. The advantages of obtaining a faster result are lost if the staff mustlook for a physician to take clinical action. If staff had a management pro-tocol available, they could take action immediately upon receipt of the testresult by altering insulin dosage or administering food or intravenousglucose.

The link of POCT with patient outcome was examined in a study con-ducted in the cardiovascular/radiology setting [13]. Patients were requestedto arrive 2 hours before procedure for preparation; however, despite arriv-ing early, procedures frequently were delayed because laboratory resultswere unavailable. These delays resulted in open operating rooms, changesin physician scheduling, and stress and dissatisfaction for staff and patients,with the laboratory being blamed. Before a procedure, patients required cre-atinine and electrolytes to allow dosing of radiologic dyes, and coagulationtesting was required to assess for postprocedure bleeding tendency after re-moval of indwelling catheters after the procedure.

POCT was seen as the optimal solution; however, implementation ofPOCT did not result in the expected improvement in outcome (ie, meetingscheduled procedure time). Improvement was noted only after changeswere made in the overall procedure scheduling and management. Intercomsystems that communicated between staff in the procedure rooms and staffpreparing patients allowed for better timing and preparation of patientswith rooms that were becoming available. POCT was only one of manysteps that needed to be accomplished before a procedure could be started.A delay in any step could lead to delays in the final outcome, meeting thescheduled procedure time. Once the patient preparation management path-way was streamlined, significant improvements in meeting scheduled proce-dure times were accomplished [13].

Therefore, implementation of POCT must be linked to changes in patientmanagement to improve outcomes. The cardiovascular/radiology exampleillustrates that laboratory testing is only one component of a complex path-way of care that ultimately leads to the patient outcome. Improvement inone step of the pathway does not guarantee improved outcome without con-sidering all of the other aspects of care, and, in this case, other sources fordelays.

Communication is fundamental to achieving the desired improvements.All staff needs to understand the total pathway to relate their individualrole within that pathway of care. Unfortunately, physicians and laborator-ians have different understandings of the role of POCT in the patient carepathway. Physicians view POCT as the same test as core laboratorymethods, only faster, whereas laboratorians understand that POCT is a dif-ferent methodology, with inherent precision and accuracy biases and unique

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limitations. Both perspectives are required in the development of patientcare pathways and optimizing the delivery of patient outcomes.

Although physicians simply may want to use their same treatment cutoffsand guidelines between core laboratory and POCT technologies, laborator-ians understand that these treatment protocols may need to be modifiedbased on the technical performance of the POCT method selected and itsagreement with the core laboratory. As an example, POCT creatinine was im-plemented in a hematology/oncology clinic to allowmore rapid dosing of che-motherapy and reduce patient wait times [14]; however, despite the POCTand core laboratory using the same creatinase (enzymatic method), thePOCT method categorized more patients as having abnormal renal functioncompared with the core laboratory. This would have resulted in significantlydifferent dosages of chemotherapy in the same patient depending on whetherPOCT or core laboratory results were used. Ultimately, the pharmacy had tochange the management cutoffs based on the test method to ensure compara-ble dosing between the core laboratory and POCT methods [14].

These test differences indicate the need to clearly communicate and dis-tinguish the methodology of the test with the result. It is not sufficient towrite a ‘‘creatinine’’ result in the patient’s chart without distinguishingwhether the result was ‘‘POCT creatinine’’ or ‘‘core laboratory creatinine.’’The adoption of electronic medical records emphasizes even more the needto consider unique test methodologies when fields are established in themedical record. Electronic records have the ability to be distributed and ac-cessed widely in a health system, with staff adding test results from the corelaboratorydas well as physician office practices, inpatient POCT, and homenursingdto the same record. Test results can be separated by name (eg,POCT glucose, laboratory glucose, blood gas glucose); however, CLIA reg-ulations also require the location and laboratory director of the test to belinked to the final test result. Because locations with different addressescan have unique CLIA certificates, a patient’s medical record in a large in-stitution easily could have dozens of different test names (eg, inpatientPOCT glucose, laboratory glucose, Dr. Smith’s glucose, Dr. Jones’ glucose,Dr. Miller’s glucose).

Because this could be confusing to the physician interpreting the test,some institutions have simplified the complexity of this problem by separat-ing testing into two test fields: POCT and core laboratory methods. Corelaboratory methods generally are resulted through an instrument interfacefrom a laboratory information system and automatically tagged with thelaboratory director and appropriate CLIA certificate. POCT results, how-ever, can be entered electronically or manually. Electronic entry can be han-dled the same as laboratory test results by automatically linking theappropriate CLIA-required information. Manual data entry necessitatesthe staff to remember to enter the appropriate information with every testresult. This task can be simplified by just requiring staff to select their loca-tion from a dropdown screen before a test can be resulted (Fig. 2). This


dropdown screen is linked electronically to the required information, cur-rent CLIA certificate, and director and ensures that every test capturesthe necessary information to interpret the test result and meet regulatorycompliance. By setting up the system to require the location with every re-sult, staff is automatically prompted and cannot complete the task withoutthe necessary location information.

Clinical pathways and management protocols are a good means of assist-ing physician interpretation and bridging the laboratory–clinical communi-cation gap. Resources are available to assist the development of clinicalpractices and pathways of care. The National Academy of Clinical Bio-chemistry (NACB) has conducted a systematic review of the scientific liter-ature linking POCT to patient outcome and published Laboratory MedicinePractice Guidelines titled ‘‘Evidence-based practice for POCT’’ [15] (avail-able at www.nacb.org). These peer-reviewed guidelines represent a consensusof best practices from the literature.

Use of these guidelines helped to revise a chest pain pathway for the man-agement of patients in the emergency department (Table 1). Before revision,

Fig. 2. Sample POCT result form for pH test reporting to a patient electronic medical record.

POCT result form contains fields for selecting positive or negative results from amniotic fluid

pH (with appropriate reference intervals) or free text fields for reporting numerical results

and comments. This POCT form requires selection of the site location linked to the site’s

CLIA certificate (Organization/CLIA#) before results can be verified and reported to the pa-

tient medical record. Staff enter the test result with any comments in the appropriate field,

and select the testing location from the dropdown menu to attach the appropriate CLIA certif-

icate to the POCT result. The patient’s electronic record will display only the test result; by

right-clicking the mouse, staff can view associated comments and test location/CLIA certificate

information required for regulatory compliance.

http://www.nacb.org

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patients with chest pain would receive ECG, physical, and laboratory testingon presentation to the emergency department for glucose, electrolytes, cellcounts, urea nitrogen, and creatinine. Cardiac marker testing included initialtotal creatinine kinase (CK) and cardiac-specific muscle/brain isoenzyme(MB) fraction if total was elevated plus troponin. Extra tubes of bloodwere collected and held in case additional testing was required. The totalCK/CK-MB was repeated every 3 to 6 hours, with troponin added every9 hours until the patient was admitted or discharged. After review of theNACB practice guidelines for cardiac markers published in 2002 in conjunc-tion with the American College of Cardiology [16], the chest pain pathwaywas streamlined so that the cardiac marker test consisted of just an initialqualitative POCT troponin followed at 6 hours with a quantitative troponintest. The revised protocol defined admission if any of the diagnostic testswere positive (ECG or laboratory) and an end point for discharge at 6 hoursfor two negative ECGs, two negative troponins, and a negative stress test.The qualitative POCT provided a fast, initial result that the clinicians coulduse to manage the patient rapidly on presentation to the emergency room,followed by a more definitive laboratory troponin at 6 hours to decide ondischarge. Less blood was collected from patients, and fewer tests were con-ducted (eliminated reliance on multiple timepoints of CK/CK-MB). Thispathway also assisted physicians in ordering the right test (POCT versus

Table 1

Laboratory testing performed as part of an emergency department chest pain care pathway.

Testing has been streamlined and relies on the cardiac-specific troponin marker over creatinine

kinase. Revision of this pathway defines a 6-hour end point for patient disposition and de-

creases the number of phlebotomies and amount of blood

2001 2004

At presentation (hour 0)

� Stat troponin

� CK (reflex CK-MB)

� Automated complete blood cell count

� Chemistry panel

Electrolytes

Serum urea nitrogen

Glucose

� Serum hold tube

At presentation (hour 0)

� Stat troponin

� Automated complete blood cell count

� Chemistry panel

Electrolytes

Serum urea nitrogen

Glucose

Hour 3

� CK (reflex CK-MB)

Hour 6

� Stat troponin qualitative (POCT)

� Lipid panel (or fasting preferred)

Hour 9

� Troponin

� CK (reflex CKMB)

� Repeat every 3–6 hours until discharge

Discharge or admission

� Lipid panel (or fasting preferred)


laboratory testing) at the right time in the patient’s care (admission versus 6hours postadmission) and standardized clinical management, thereby reduc-ing practice variation. By embedding this pathway into an electronic order-ing system, test ordering can be standardized for patients with the samediagnosis. This pathway improves consistency of care and enhances commu-nication between the clinician and the laboratory, because the physicianknows when to order the right test for the patient and the laboratory nowknows why a test is being ordered and can relate the test back to the pointin a pathway of care for that patient. Recent revisions of the NACB cardiacguidelines relating to POCT are included in the recent ‘‘Evidence-basedpractice for POCT’’ guidelines, and all of the published NACB practiceguidelines are available through links from the National Guideline Clearing-house at Agency for Healthcare Research and Quality (AHRQ) (www.guideline.gov).

Summary

POCT offers the potential for fast test results and more rapid patienttreatment; however, concerns over the quality of test results and difficultiesin managing the documentation from multiple sites, operators, and deviceshave created challenges to the widespread adoption of POCT. Practicalmanagement of POCT requires an organizational structure with definedstaff roles in the supervision of testing and day-to-day operation. Thereare multiple sources of potential error in POCT, including environmentaland operator factors. Development of an overall quality assurance programfor POCT should consider the entire preanalytic, analytic, and postanalyticphases and use computerized device features to automate manual steps, sim-plify the testing process, and reduce necessary decision making. POCT isa different methodology from core laboratory testing, and the laboratoryneeds to establish effective channels of communication with the physicianto distinguish test results, highlight test limitations, and assist with result in-terpretation. Pathways of care and management protocols help with com-munication and standardize practice. Resources are available through theNACB Laboratory Medicine Practice Guidelines and National GuidelineClearinghouse to help use POCT in the most effective manner for improvingpatient outcome.

References

[1] Stephens EJ. Developing open standards for connectivity. In Vitro Diagnostics Technology

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