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In 2002, the Massachusetts General Hospital Clinical Pathology Division established a satellite laboratory staffed by laboratory-based medical technologists in our emergency department (ED "Kiosk") to perform a limited menu of rapid point-of-care tests. The initial menu included whole-blood cardiac markers, urine dipstick testing, urine pregnancy testing, and whole-blood glucose offered on the day shift only 5 d/wk. Implementation of these rapid tests resulted in an 87% decrease in turnaround time and was associated with a decrease in ED length of stay of 41 minutes for each patient tested. Since 2002, the menu and operations of the ED Kiosk have continued to evolve including the addition of new tests to the menu (rapid influenza, rapid RSV, rapid Strep A, urine drugs-of-abuse, and whole-blood d-dimer) and expansion of the hours of operation to 7 days, 24 h/d. Some of the new tests were shown to decrease ED length of stay (urine drugs-of-abuse testing, rapid d-dimer), whereas others were implemented to permit rapid diagnosis and triage of patients presenting to the ED. In this article, we describe our experiences with the operation of the ED Kiosk during an 8-year period.

The authors report an evaluation of the Roche Cardiac Reader point-of-care troponin T assay (Roche Diagnostics, Indianapolis, IN) in an emergency department STAT laboratory. Overall, the Cardiac Reader showed excellent agreement with the Elecsys troponin T assay (Roche Diagnostics, Indianapolis, IN) (Y 1.09X 0.05, r 0.96) over the range of values from 0.1 ng/ml to 2 ng/ml. The Cardiac Reader agreed with the laboratory-based assay in terms of the diagnostic classification of the patient in 96.2 of cases. Only one of the discordant results (< 1) could be considered clinically relevant, albeit the discordance would most likely not have occurred on serial testing, as is commonly performed. These data demonstrate that the Roche Cardiac Reader troponin T assay can be performed successfully outside the laboratory in a point-of-care emergency department setting. In contrast to other point-of-care devices for testing of troponin, the Roche Cardiac Reader gives equivalent numeric values to the manufacturers clinical laboratory method. Systems available for troponin I testing at the point of care, and in the central laboratory, typically yield results that correlate, but produce different numeric and cutoff values. This may create issues when comparing emergency department point-of-care test results with serial follow-up laboratory values after patients are admitted to hospital units. Likewise, cutoff values may be different, and this requires careful consideration of the format for reporting the point-of-care test during implementation. In contrast, the Cardiac Reader troponin T system eliminates this problem and, therefore, may be easier to standardize with the clinical laboratory.

Influenza is an ongoing public health threat. The accurate diagnosis of influenza is a significant challenge to health care providers, clinical laboratories, and public health officials because the diagnosis of influenza is not easily made on the basis of the clinical presentation alone. Identification of influenza infection as soon as possible after onset of symptoms improves patient management and infection control. Traditional rapid influenza diagnostic tests (RIDTs), such as lateral flow immunoassays, are simple to use and provide results in less than 30 minutes at the point of care. These RIDTs are less accurate than more complex, but more definitive, tests performed in centralized laboratories. A new era of influenza diagnostics is emerging in which more accurate and objective next-generation RIDTs, based on fluorescent immunoassay technology, are available. We review recent studies on the performance of this technology and enumerate its advantages compared with traditional RIDTs. This technology offers an opportunity for significant improvement in how influenza is managed.

The National Academy of Clinical Biochemistry (NACB) has developed clinical practice guidelines for occult blood testing. Annual or biennial guaiac-based fecal occult blood testing (FOBT) should be performed in average-risk asymptomatic patients older than 50 years to reduce mortality from colorectal cancer (CRC). Although the current literature is insufficient to favor central laboratory FOBT over point-of-care testing, experts do not recommend performing testing that screens for CRC at the point of care. Home collection of specimens with analysis either in the physician's office or laboratory is recommended. Either guaiac-based or immunologic methods can be used, but more evidence is necessary to recommend the preferred methodology. Occult blood testing is frequently used in the hospital setting for purposes other than CRC screening. According to the literature, other applications of occult blood testing are controversial. The utility of FOBT to detect gastrointestinal bleeding and assess bleeding risk in patients on anticoagulation is questionable. Intensive care unit patients may benefit from gastroccult testing to detect gastric bleeding, but no large studies have been performed to demonstrate improved outcomes.

Emergency department (ED) overcrowding and prolonged patient length of stay (LOS) is an increasing problem in most American hospitals. Some reports in the literature have suggested that point-of-care (POC) testing may help alleviate ED overcrowding by providing rapid test results to aid in triage decisions and administration of appropriate therapy. In our hospital, a limited menu of POC tests was shown to decrease ED LOS and reduce the number of hours the ED was on divert status. In recent years, the menu of tests available in POC formats has continued to expand raising the possibility that more patients could receive rapid POC results and potentially have a greater impact on ED operations. We analyzed ED laboratory test ordering patterns to determine what impact an expansion of the ED POC menu might achieve using a selected group of instruments. The ED at Massachusetts General Hospital evaluated approximately 76,000 patients in 2005, of which 25% are admitted. Of these, approximately 76% received laboratory testing. The average number of tests per patient for those that received testing was 7.7 assuming scoring of standard medicare panels as one test for the panel, and 75% of patients had 5 or more tests/panels ordered. Of tests performed in our ED, 9% are now performed at the POC in our satellite laboratory (blood glucose, cardiac markers, dipstick urinalysis, urine pregnancy testing, and rapid Strep A and influenza testing) and 66% of patients that receive testing have some test performed at the POC. Overall, the most common laboratory tests requested are the basic metabolic panel (15.0% of tests), complete blood count (13.2%), calcium/phosphate/magnesium (9.7%), hepatic panel (6.7%), urinalysis (6.2%), cardiac markers (5.2%), prothrombin time (5.1%), amylase/lipase (4.8%), urine pregnancy (4.1%), toxicology (2.9%), and partial thromboplastin time (2.8%), respectively. Of patients that received testing, 88% had a complete blood count; 86%, a basic metabolic panel; 68%, a calcium/phosphate/magnesium; 58%, a hepatic panel; 47%, a urinalysis; 39%, a prothrombin time; 36%, an amylase/lipase; 32%, a urine pregnancy; 28%, cardiac markers; and 2.1%, a toxicology analysis. Of all tests, 71.6% were chemistries, 23.4% were hematology tests, and 5% were microbiology tests. Using a hypothetical combination of a rapid chemistry analyzer, a conventional hematology cell counter, and other true POC testing devices, 75.6% of the tests requested by our ED could be performed in our satellite laboratory. With this menu, all requested testing could be performed on 62% of patients that receive testing. The remaining 38% would require some other additional test(s) to complete the laboratory evaluation.

The Biosite Triage D-dimer is a new, rapid assay utilizing EDTA whole blood or plasma that can be used at the point-of-care or in a central laboratory. Most coagulation assays, including many D-dimer assays, require citrated plasma, but the Triage D-dimer has not been previously studied using citrated plasma specimens. Seventy-four citrated plasma specimens on which D-dimer testing was requested for clinical testing were assayed on both the VIDAS and the Triage D-dimer systems. A subset of 29 of these specimens also had an EDTA specimen collected simultaneously and were assayed using the Triage D-dimer system. Diagnostic agreement between Triage citrate and VIDAS citrate, Triage EDTA and VIDAS citrate, and Triage citrate and Triage EDTA was ≥93%. Correlation coefficients (R2) were 0.86 for Triage citrate versus VIDAS, 0.93 for Triage EDTA versus VIDAS, and 0.96 for Triage citrate versus Triage EDTA. Diagnostic agreement was not changed after adjusting for the dilutional effects of citrate. Bland-Altman bias plots showed no bias between Triage citrate and Triage EDTA results if citrate results were adjusted for the dilutional effects of citrate. Triage results, whether EDTA, citrate, or adjusted citrate, tended to underestimate the VIDAS result at the low end and overestimate at the high end. In conclusion, the results suggest that citrate is a suitable alternative to EDTA for the Triage system. These data suggest that the Triage D-dimer compares favorably with the VIDAS, albeit the cutoff values are different. Further studies are warranted to confirm the possibility that Triage D-dimer is a suitable alternative to VIDAS.

Previous reports concerning the utility of pointofcare testing POCT in the emergency department ED setting have produced mixed results. Testing for cardiac markers at the point of care has attracted considerable interest in the literature but few hospitals have reported results of experience in clinical practice. The availability of new therapies for acute coronary syndromes and the development of chest pain pathways in many institutions has made POCT for cardiac markers a potentially important topic in laboratory medicine. The authors present a prospective study on the implementation of POCT for cardiac markers in an ED of an urban academic medical center. Data concerning operations, physician satisfaction, and practical experiences from implementation were reviewed over a 1year time frame. Implementation of cardiac markers in a multitest satellite laboratory as part of an interdepartmental process improvement effort was associated with improved physician satisfaction with laboratory services from a score of 2.06 to 4.00 scale 1 to 5, a 48minute decrease in ED length of stay for patients that received cardiac marker testing, and a decrease in ED divert hours of 25. Significant implementation issues were encountered concerning test menu, cutoff values, the use of quantitative versus qualitative testing, and issues concerning laboratory operations. Each of these challenges required careful planning of the ED satellite laboratory operations to facilitate successful implementation. Cardiac marker testing at the point of care can be implemented successfully in an ED setting using trained laboratory staff in a satellite laboratory facility. When performed as part of an overall organizational effort in the ED, POCT may contribute to a decrease in ED lengthofstay, a decrease in ED divert hours, and an increase in physician satisfaction. Pointofcare testing POCT for cardiac markers using currently available technologies requires careful consideration of technical issues including menu, cutoff values, the use of qualitative versus quantitative technologies, and methods to reconcile test results with those obtained on different technologies in the central laboratory.