Supervisors at two large hospitals discuss their experience with point-of-care blood gas testing.

In the world of health care, nothing has been more controversial during the past several years than point-of-care (POC) blood gas testing.1 As blood gas testing has moved from the laboratory to the patient’s bedside, several important questions have been raised. How will the tests be ordered? Who will fill out the requisition? Who will run quality-control checks on the equipment out on the floors? How will these be recorded for the regulatory agencies? When a test is run, what will happen to the results?

Here, supervisors from two large health care systems-Marianne Watters, MT (ASCP), Director of Pathology, Parkland Health and Hospital System, Dallas, and Catherine M. Foss, RRT, RPFT, Arterial Blood Gas Laboratories Supervisor, University of Michigan, Ann Arbor-share their experiences with POC testing.

RT: Are you using handheld or bench analyzers at the point of care?

Watters: At Parkland, we have incorporated both handheld devices and bench analyzers based on the needs of the specific sites.

Foss: At the University of Michigan, where POC testing has been in place for more than 2 years, there are bench analyzers for arterial blood gases outside of every intensive care unit (ICU) and handheld devices in the satellite clinics. Respiratory care services has also collaborated with the pathology department to share responsibilities. Respiratory care is responsible for the ICUs while pathology is responsible for the satellite clinics.

RT: At what sites have you instituted POC testing?

Watters: Parkland has placed analyzers in its surgery department and trained the perfusionists to analyze the specimens. It has also instituted POC testing in the neonatal ICU and trained the respiratory therapists to conduct the testing. They also use handheld devices in the AIDS primary care clinic. Regardless of the site, there must be a backup system, which may be needed in a number of situations, including when one receives questionable results, or if there is an air bubble, a clot in the cartridge, or if the equipment does not pass a quality-control check. Specimens are transported from the clinical setting to the main laboratory when backup is required.

RT: Why did you implement POC testing?

Watters: Turnaround time and the capacity for immediate communication between physician and patient are the primary reasons.

Foss: Physicians, nurses, and RCPs wanted faster turnaround times between sample acquisition and the release of results.

RT: Did you use a multidisciplinary team approach for implementation?

Foss: All point-of-care decisions were discussed and continue to be reviewed on a monthly basis by the critical care committee. This committee includes the medical director, respiratory therapists, nurses, and pulmonary laboratory [staff]. If the monthly volume does not support the specific analytes selected for each site, changes are made. For example, when new equipment was recently purchased, the committee evaluated the addition of available analytes and chose to add lactate to two of the six sites. Again, all costs and outcomes are carefully evaluated on a monthly basis before changes are made.

RT: Were there barriers to implementation?

Watters: In order for POC testing to be successful at Parkland, it was necessary to take steps to ensure the staff would accept the new technology. By involving staff in the decision-making process, such as planning who would conduct the testing and the training, POC testing has gotten a positive reception.

RT: Have you evaluated outcomes in medical or financial terms?

Watters: Parkland has not had the opportunity to scientifically evaluate the change, but reports of perceived benefits from physicians and other staff members have been sufficient to continue POC testing.

Foss: The University of Michigan is in the process of evaluating the impact of POC testing on cost and patient outcomes, and is comparing the outcomes of the central laboratory with POC scenarios. Labor costs are evaluated in addition to issues related to supply costs and the number of samples processed in each location. It is also important to evaluate the costs related to specific disease processes, such as acute respiratory distress syndrome. This information is also critical to evaluate the indwelling in vivo systems.

RT: What are the perceived benefits by physicians and other health care employees?

Watters: At Parkland, the physicians in both primary care sites and those in the neonatal unit continue to report high levels of satisfaction. The ability to have immediate results has benefitted both the physicians and the patients, particularly in the AIDS clinic, where having to travel to another site for testing would place a great burden on the patient.

Foss: All of the caregivers in the ICU are pleased with the decreased turnaround time for test results, improving their ability to meet patients’ needs. Airway and ventilator management decisions may be made more rapidly because of the immediate availability of sample results. Although the perception is that turnaround times have improved, specific measurements are important. The 20-minute average measured in the central laboratory 2 years ago may also occur in POC testing if several samples arrive simultaneously or equipment malfunctions.

RT: Who is responsible for training staff and maintaining competence for POC testing?

Watters: The laboratory maintains the responsibility for the Clinical Laboratory Inspection Act (CLIA) certificate, training and competency assessment, and quality-control review.

Foss: The pulmonary laboratory, respiratory services, and pathology department share the responsibilities. The RCPs in the ICUs obtain and process the arterial blood samples. The pulmonary laboratory provides the supervision, data entry, and training and competency assessment. It also performs the quality-control and proficiency testing for all of the hospital units. The pathology department performs these services for the satellite clinics. The pathology department holds one CLIA certificate for the entire system. In both cases, there is significant collaboration between departments.

RT: How is data maintained in the laboratory information system (LIS) and hospital information system (HIS)?

Watters: Some of the [testing] units allow staff to use a docking station and download the data to the LIS. In many cases, the laboratory manually enters data into the LIS in an effort to save keystrokes for those who are analyzing the specimens and caring for the patient.

Foss: The pulmonary laboratory has been manually entering data also to save keystrokes for the RCPs analyzing the specimens. The development of improved systems for data management continues to be a challenge.

RT: How are decisions made to introduce POC testing in other areas of the health care system?

Watters: Although several departments were initially involved in the implementation of POC testing at Parkland, our experience has taught us that the pathology department is most effective in deciding where expansion is warranted. Companies interested in placing equipment in Parkland must work with and be approved by the pathology department. This gives the hospital control over the types of devices that are considered and guarantees consistency throughout the hospital system. This system is also important because pathology maintains the responsibility for the CLIA certificate.

Correlation studies between existing and new instruments are required by regulatory agencies and must be performed a minimum of every 6 months between instruments with the same analytes.

RT: What have been your major challenges with POC testing, and how have you solved these challenges?

Foss: Finding space for the laboratories of POC testing presented major challenges. Most hospitals were not designed to place laboratories within the ICU. Finding space that met regulatory requirements has prompted each site within the hospital to move at least once to improve compliance. In addition, the service has grown from two to six sites in the past 2 years at the University of Michigan.

Some systems include large test panels that measure multiple analytes. For these systems, special attention must be paid when selecting syringes and anticoagulants. [The National Committee for Clinical Laboratory Standards (NCCLS) documents address these issues in detail.2,3 ] Clots in the cartridge have been a major concern. The anticoagulant selected must be appropriate for the analytes tested. This issue has limited selection when buying syringes.

Another challenge is maintaining and troubleshooting several systems in a large hospital. We have reviewed information system options on several pieces of equipment, looking for assistance in this area. With its most recent purchase, the University’s data manager now allows the reference site to view a piece of equipment at a remote site half a mile away. In many cases, the operator in the reference laboratory will be able to resolve equipment errors at the remote site without physically traveling to the site. An automatic quality-control option for the remote equipment can also be started from the reference laboratory. If the therapist is at another site performing maintenance and another piece of equipment requires repairs, the computer will page the therapist to attend to that specific piece of equipment. The use of these information systems should result in significant time-savings for our department.

Moving instruments out of the central laboratory may raise concerns about equipment not being monitored at all times. A lock-out feature on the equipment and password-protected access are important in its design. The area where the equipment and supplies are stored should also be secure to maintain infection control. It is critical to verify competence in all the preanalytical phases of sample acquisition. [Both Parkland and University of Michigan have accomplished this through the use of clearly defined responsibilities for each department involved in the testing process.]

RT: How has implementing POC testing affected patient care decisions?

Watters: The ability to perform A1C hemoglobin testing on the diabetic patient allows for immediate intervention rather than the physician having to call the patient in for a possible follow-up visit. The ability to obtain prothrombin results also allows for an immediate determination of the need for therapy. [The benefits of the immediate availability of coagulation results in patients undergoing cardiopulmonary bypass was demonstrated in 1994 by Despotis et al.4]


One recent study at Methodist Clinical Laboratory Services, Clarian Health Partners, in Indianapolis, showed that POC resulted in an annual savings of $392,336.5 For the most part, however, the literature is sparse when it comes to studies documenting the financial and medical impact of POC testing. Those studies that do exist are mixed, documenting both positive ad negative outcomes. The challenge for the medical community is to document the perceived benefits of POC and expand POC testing in those areas in which it is most beneficial.

The NCCLS has published a document on POC testing that may be helpful to those considering implementing POC testing. This trend to move testing closer to the patient’s bedside is likely to continue as the benefits of POC are documented. The challenge remains to identify the needs of each patient care site and apply solutions specific to those needs.

Susan B. Blonshine, RRT, RPFT, is president of Technical Education Consultants, Mason, Mich.


1. Smith I. The walls come down. RT. 1998:10:61-67.

2. National Committee for Clinical Laboratory Standards. Point-of-care IVD testing: proposed guideline (NCCLS Document AST2-P); 1995.

3. National Committee for Clinical Laboratory Standards. Simultaneous measurement of blood gases, electrolytes, and related analytes in whole blood: patient collection and reporting considerations, approved guideline (NCCLS Document C32-A).

4. Despotis GJ, Santoro SA, Spitznagal E, et al. Prospective evaluation and clinical utility of on-site monitoring of coagulation in patients undergoing cardiac operation. J Thorac Cardiovasc Surg. 1991;107:271-279.

5. Bailey TM, Topham TM, Wantz S, et al. Laboratory process improvement through point-of-care testing. Jt Comm J Qual Improv. 1997;23:632-380.