The results of patient laboratory testing are the cornerstone of medical diagnoses and treatment plans. Laboratory results are trusted pieces of information that medical professionals count on to determine the appropriate course of treatment for their patients, and therefore the validity of such results is of critical importance. Because of perceived efficiency in both turnaround time and proximity to the patient, the demand for point-of-care testing (POCT) has increased, and its use has become more widespread. Therefore, it is necessary to analyze the POCT process to identify possible sources of error, improve the quality and reliability of test results, and ultimately improve patient care.
In response to this need, the Clinical and Laboratory Standards Institute (CLSI) published a guideline, Quality Management: Approaches to Reducing Errors at the Point of Care; Approved Guideline (POCT07-A), which outlines a standardized error tracking system to manage risks and improve quality of POCT. This guideline proposes a set of indicators for each analytical process for incorporation into a point-of-care quality program. It also presents the user with predefined common causes of error and respective error prevention mechanisms for a more standardized reporting method.1
Lou Ann Wyer, MS, MT(ASCP), Clinical Specialist, POCT/QM at Sentara Healthcare in Norfolk, Virginia, is the chairholder of the CLSI subcommittee that authored the document. She believes POCT07-A fills an important need in the clinical laboratory community, and has many practical applications. She says, “As POCT continues to grow, there are some mature programs and there are some programs that are just getting started or are struggling. POCT07-A addresses this broad spectrum of POCT programs with a goal to improve the performance of POCT using different indicators. Many of them are listed in the tables of the document and are applicable to all aspects of testing.”
Valerie Ng, PhD, MD, Director, Clinical Laboratory at Alameda County Medical Center/Highland General Hospital in Oakland, California, and an advisor to the CLSI subcommittee that produced POCT07-A, believes this guideline will help to dispel the myth of infallibility of laboratory results. She adds, “Although many point-of-care tests have been developed to be virtually foolproof, there are still points at which human error can cause an incorrect test result. Medical decisions are made quickly once the point-of-care test result is available, so it is critical the results are accurate. This guideline provides a framework and a logical process for identifying possible weak points in POCT. Correction of these weak points helps to ensure accurate test results, which leads to optimal patient care and safety.”
Benefits and Challenges of POCT
As noted in POCT07-A, there are benefits and challenges involved in both POCT and testing done in a centralized laboratory. Although the costs to perform POCT may initially be higher, there are other advantages that make the decision about where certain tests should be performed more complex. Benefits of POCT include the following:
Access to test results in shorter time frames leads to earlier implementation of treatment decisions, which may result in better patient care.
Specimen transport time is eliminated or minimized, leading to faster testing after acquisition and fewer concerns related to sample stability, which can be critical for some tests (eg, blood gases, lactate).
The risk of preexamination errors that may accompany traditional laboratory testing, such as the handling, transport, and labeling of samples, is reduced.
Sampling-related blood loss is decreased, an important feature in settings such as the operating room or intensive care unit (ICU), where blood conservation is key, or in pediatric testing. Some analyzers used in central laboratories have test menus that require a minimum sample size, whereas most POCT devices use smaller samples.
Challenges related to POCT include:
Standardization of testing among the various testing locations and the central laboratory
Information management; ability to link all POCT data from different testing locations to each other and to the central laboratory within a medical institution
Documentation of tests performed at remote locations
Logistics of training and competency verification of numerous testing personnel with diverse educational backgrounds
Logistics of inventory management for numerous testing locations
Preanalytical techniques, such as proper specimen collection and handling1
Wadid Sadek, PhD, retired professor of clinical chemistry and a member of the CLSI subcommittee that produced POCT07-A, believes that in the context of those challenges, institutions performing POCT can use POCT0-7-A to perform risk assessments and establish effective quality control.
Dr. Sadek also recommends the document as a tool to help establish effective quality control in POCT because it discusses important considerations of laboratory testing, such as regulatory requirements, manufacturer-provided information, laboratory environment, and the medical application of the tests performed.
Practical Resources for Reducing Errors
POCT07-A was designed as a functional, practical resource with many useful tables and tools for the user. It includes tables that correspond to the preexamination, examination, and postexamination phases of testing. The tables are organized by potential sources of error, the analytes that may be affected, and suggestions to mitigate the potential error. The guideline also includes specific tools that POCT personnel can use to help document and track errors.1
Ms. Wyer highlights a case study in the document that is helpful in explaining the process of risk assessment. It guides the reader through the process of identifying an error, documenting it, and taking corrective action. She notes that if a POCT coordinator is just starting out, this guideline provides forms that can be modified, and examples of data presentations that are visually appealing and easily interpreted.
Dr. Ng notes that the aim of the POCT07-A guideline is to raise awareness of all the steps in the testing process where things can go wrong. She says, “It is hoped that the users of this document will assess the practice, identify areas of weakness, and put into place corrective systems. In doing so, they will ensure that test results will truly be accurate, and patients will be treated correctly.”
Lou Ann Wyer, MS, MT(ASCP), Clinical Specialist, POCT/QM, Sentara Healthcare, Norfolk, Virginia, USA
Wadid Sadek, PhD, Stuarts Draft, Virginia, USA
Valerie L. Ng, PhD, MD, Director, Clinical Laboratory, Alameda County Medical Center/Highland General Hospital, Oakland, California, USA
CLSI is a volunteer-driven, membership-supported, nonprofit organization dedicated to developing standards and guidelines for the health care and medical testing community through a consensus process balancing the perspectives of industry, government, and the health care professions. For additional information on CLSI, visit the CLSI website atwww.clsi.orgor call 610.688.0100.