POCT : Point of Care testing - Introduction, Utility and Management

Point-of-care testing (POCT) is an emerging concept in laboratory medicine and has attracted considerable interest in the medical literature. Recent experience has revealed a variety of applications for these new technologies in
hospitals, outpatient clinics, and home-care settings. Diagnostics manufacturers continue to invest significant resources in developing point-of-care (POC) technologies creating new opportunities to redesign the delivery of laboratory services. 

Fig. POCT Process

Point-of-care testing (also called bedside or near-patient testing) has been defined by Price and Hicks as “all testing not undertaken in a central laboratory… that is undertaken close to the patient, with the result leading to a possible change in the care of that patient”. According to the Joint Commission on Accreditation of Healthcare Organizations, POCT is differentiated from central-laboratory testing in that it does not require a physical laboratory; that is, the laboratory exists at each point-of-care. The specimen is obtained, the test performed, and the result reviewed where care is provided. Despite various attempts, a rigorous definition of POCT is somewhat elusive, if not artificial. However, differentiating POCT from central laboratory testing is a useful concept from the management perspective because it involves testing by non-laboratory personnel using specialized technologies adapted for near-patient bedside applications.

POCT had its beginnings many decades ago when physicians performed testing in hospital laboratories with or without the aid of a technologist. An archaic example of POCT was the practice of tasting a patient’s urine to detect the presence of glycosuria indicative of diabetes mellitus.

Utility Of POCT:

POCT may be used in a variety of applications like patient screening, diagnosis, medical management, and management of patients. Medical management refers to testing performed for the purpose of managing a clinical condition such as bedside capillary glucose testing to maintain glycemic control in diabetic patients. In contrast, management of patients refers to testing performed to assist in managing the patient within the hospital. For example, cardiac markers may be used in conjunction with clinical data to triage patients to one of several different types of hospital beds such as an observation unit, a general medical unit, or intensive-care setting. The decision is more related to hospital operations than medical issues with the aim being to provide the most cost-effective and clinically appropriate setting in which to care for the patient. In all of the above applications, the key to the selection of POCT versus the central laboratory is the priority of rapid turnaround time over other considerations. Although the unit cost of POCT tends to be higher than central-laboratory testing, when the total cost of care is considered, POCT may in some cases prove to be more cost effective.

Fig. Example of POCT for INR

CLINICAL UTILITY OF POINT-OF-CARE TESTING: SOME EXAMPLES 

Screening: Fecal occult blood, cholesterol, capillary blood glucose testing for diabetic screen at a health fair 

Diagnosis: Pregnancy testing, cardiac marker, rapid Strep A 

Medical Management: Bedside glucose testing, gastric occult blood, blood gases, electrolytes, activated clotting time 

Management Of Patients: Cardiac markers used to triage patients to an observation unit versus an inpatient medical unit, urine pregnancy screen as a pre-radiology test in a trauma unit 

Home Use: Patient Self Monitoring: Capillary glucose testing, ovulation testing 

FACTORS TO CONSIDER IN THE VALIDATION OF POINT-OF-CARE TECHNOLOGIES 

• Ease of use, ease of training 

• Data management 

• Accuracy 

• Precision 

• Reference ranges 

• Interferences 

• Crossover studies to existing methods 

• Quality control frequency and ranges 

• Sample selection 

MANAGEMENT OF POINT-OF-CARE IN THE HOSPITAL

Traditionally, POCT was unregulated and consequently little effort was made by hospitals to establish an approach to managing these technologies. Predictably, issues concerning the quality of test results became apparent resulting in the establishment of regulatory requirements (see below) that have been enforced by hospital accreditation organizations. Failure to comply with regulatory mandates may have major consequences. The need to address regulatory requirements combined with rapid expansion of POCT technologies has resulted in a concerted effort by institutions to manage POCT as a formal hospital program.

The first step in developing a strategy to manage POCT involves setting up an interdisciplinary POC management team, including the laboratory, physicians, and nurses. The POC team has the responsibility of determining the test menu, selecting technologies, establishing policies and procedures, ensuring training and regulatory compliance, and providing advisory assistance to the end users of POC technologies. Once a POC team has been established, a management structure must be put in place to ensure that the team has the authority to implement new initiatives and to perform corrective action where necessary. This committee provides high-level oversight and has interdisciplinary authority to mandate compliance with the POC program. Beneath the steering committee is the Point-of-Care Management Team, composed of a medical director, a laboratory program manager, a nurse manager, and a medical technologist. The POC management team is responsible for direct oversight of POCT, determining medical need, selecting technologies, establishing policies and procedures, overseeing regulatory compliance and quality assurance, and ensuring that individuals performing POCT have been adequately trained. The POC management team also ensures that each site performing POCT has assigned a medical director and a manager who are responsible for supervising testing activity, ensuring regulatory compliance, and serving as a liaison to the POC management team. In this system, responsibility is placed with the end user. The POC management team serves in a consulting role and coordinates the POC program throughout the institution. However, responsibility for compliance rests with the individual testing site, not the laboratory or administration.

THE FUTURE OF POCT: POSSIBLE SCENARIOS

Technological improvements in POCT devices have resulted in greater ease of use, improved analytical performance, and lower unit cost because of the development of less expensive, more efficient platforms. Many hospitals have learned to manage POCT successfully and to improve compliance with regulatory guidelines. As the menu available at the POC expands and platforms are consolidated into multianalyte systems, new opportunities to exploit these technologies will be possible. Currently, the rate-limiting factor for most POCT programs is the ability to manage quality control and patient data in an efficient reliable manner. Also, problematic is the fact that many technologies cannot be integrated electronically (including both instrumented and noninstrumented tests) into a turnkey POC solution. Until these challenges are overcome, POCT will be limited to specialized applications in selected settings.

Assuming further improvements in POCT technology, various scenarios are possible. At one end of the extreme, virtually all turnaround-time-dependent tests could be moved out of the central laboratory to the bedside where immediate test results would be available to providers of clinical care. At the opposite end of the spectrum, POCT may remain only a minor component of total testing volume because of limitations imposed by cost, technology, and system management. The most likely outcome probably will lie between these two extremes with continued growth in POCT and expansion of the menu. Each institution will seek its own solutions depending on its unique circumstances resulting in a limitless number of permutations. Clearly, POCT will challenge laboratory professionals for many years to come.

(Source: Elizabeth Lee-Lewandrowski

Kent B. Lewandrowski

Clinical Laboratory Medicine, 2nd Ed.)