Managing a point-of-care testing blood gas service

The University Medical Center Utrecht (UMC Utrecht) is a large, 1000-bed, academic hospital with approximately 12,000 employees. The organisation consists of UMC Utrecht, Wilhelmina Children’s Hospital (WKZ) and the Medical Faculty, University of Utrecht. Special units include among others: neurosurgery; cardiothoracic surgery; neonatal and paediatric surgery and intensive care; paediatric oncology; and Level I trauma centre. 

 

The UMC Utrecht also features a Major Incident Hospital. This facility is intended for treating groups of more than five military or civilian casualties in cases of major catastrophes, war casualties or in cases of particular contagious diseases. The Department of Clinical Chemistry and Haematology (LKCH) is the central laboratory of the UMC Utrecht, covering clinical chemistry, haematology, coagulation, endocrinology, immunohaematology (blood transfusion) and point-of-care testing (POC testing).

 

 

Managing the POC testing programme

In 2001, the company board of the UMC Utrecht gave the central laboratory institutional authority to manage the POC testing programme: dealing with devices, maintenance, connectivity, user training and quality control. 

 

Commencing with the use of the i-STAT-1® System (Abbott Point of Care) devices at the Neonatal Intensive Care Unit (NICU) in 2001, our institution nowadays uses a broad selection of POC testing devices: 65 i-STAT-1 devices (NICU, PICU, ED, OR, phlebotomy units, obstetrics, and different adult and paediatric departments), 65 XceedPro (Abbott Diabetes Care) glucose/ketone devices (IC, ED and different adult and paediatric departments), eight Signature Elite (Hemochron) ACT devices (OR, PICU, Cat lab), two RapidPoint (Siemens Healthcare) blood gas analysers (paediatric Cat Lab and pulmonary function test department) and four Hemocue Hb analysers (OR). 

 

All devices are connected to the laboratory information system (LIS) GLIMS (MIPS) via the vendor-neutral POC testing data management system POCcelerator (Conworx). All POC testing results are identifiable reported to the physician via the Hospital Information System (HIS) EZIS (Chipsoft). In our institution a total of 2000 POC users are registered: nurses, physicians, perfusionists, and laboratory technicians. 

 

Investigating the potential use of POC testing

In 2000, a UMC Utrecht multidisciplinary team consisting of laboratory staff, nursing staff and physicians investigated the potential use of POC testing in the hospital and the management of appropriateness and necessity of POC tests. This team concluded that POC testing had added value in our institution, specifically in critical care medicine, and that POCT should be introduced after careful consideration and well explained clinical and/or procedural need. 

 

After implementation, it should be under constant laboratory surveillance and thus be maintained in a controlled and sensible manner. Due to the need for laboratory oversight and maintenance, the company board of the UMC Utrecht was advised by this multidisciplinary team to give the central laboratory authority to manage the POC testing programme. 

 

Turnaround times

In our institution, turnaround times at the central laboratory are generally short. For a large set of central laboratory tests (clinical chemistry, haematology, coagulation and endocrinology), a test result reporting time within 60 minutes after receipt of the sample at the laboratory is guaranteed. For those tests in which even faster result times are needed to provide rapid and appropriate patient care, the laboratory has introduced POC testing solutions to speed the time to result availability.  For this reason, POC testing is commonly performed within the field of critical care.

 

A generally accepted definition of POC testing or bedside testing is medical testing at, or near, the site of patient care.¹ Following this definition, any blood gas analyser (whether developed for POC testing purposes or central lab testing) that is put near the patient is considered a POC blood gas device. Different POC testing blood gas devices are available: classical; bench top central lab blood gas analysers; smaller, cartridge-based POC blood gas analysers; and handheld devices. A handheld device is one that is sufficiently small and light enough to be operated while being held in the hand.² All POC testing devices should be designed as extremely simple to use with little or no maintenance because they are meant to be handled by people without any training in laboratory skills.

 

Reasons for preference

One of the main reasons that our institution prefers handheld and truly portable POC testing devices in case of comparable analytical performance is the reduction of patient and sample identification errors that can be obtained while using POC testing devices right next to the patient. Although, in the meantime, solutions to prevent patient/sample identification errors have been developed for routine benchtop blood gas analysers in clinical departments, in our opinion, scanning and analysis right next to the patient is the only way to reduce identification errors to almost zero. 

 

Another important aspect of handheld POC devices is the often small sample volumes they can deal with. This is a critical issue for our NICU and PICU. Intensive laboratory testing leading to phlebotomy losses during the early weeks of birth in preterm infants is one of the main causes of anaemia.³ Use of a handheld blood gas analyser is associated with clinically important reductions in red blood cell transfusions in the extremely low-birthweight infants.⁴

 

In addition, samples can be applied directly to a handheld POC testing device without the need for sample containers, labelling or transport, which are required for analysis by a larger benchtop POC testing instrument at some distance from the patient. This, combined with fast analysis, results in a very short ‘vein-to-brain’ time, without losing focus on the patient. 

 

 

Choosing i-STAT

Because of the above-mentioned specifications, i-STAT-1 was considered the POC testing blood gas device of preference in our institution by 2001. In addition, due to the extensive critical care testing menu that is available on this single device, using a range of different cartridges, i-STAT-1 is an all-round device that can be used at different clinical departments for multiple purposes. 

 

Besides the clinical advantages of handheld POC devices, the laboratory also benefits from using a handheld blood gas device instead of a bench top analyser. Maintenance of classical benchtop central lab blood gas analysers can be quite laborious and the operator is often confronted with calibration delays. This results in a substantial down time of the analyser, which can lead to hazardous situations in critical care medicine. 

 

A back-up benchtop bloodgas analyser at a clinical department as the ICU is a luxury that often cannot be afforded with regard to the limited care budgets. Because of the i-STAT-1 disposable cartridge technology, we are not confronted with POC analyser down-time. In the uncommon situation in which an i-STAT-1 malfunctions, the department can exchange it for a spare device after contacting the POC team or, after office hours, the central laboratory. 

 

Besides this, in our case, all critical care departments have more than one i-STAT-1 device, ensuring continuation of care. Furthermore, due to the disposable cartridge technology, an i-STAT user seldom has to deal with analyser errors when analysing routine blood gas samples (low sensitivity to clots), and complex samples such as intra-osseous samples⁵ and foetal blood (umbilical cord and foetal blood sampling). A handheld blood gas analyser is also very suitable for use in our Major Incident Hospital, because in cases of major catastrophe, devices are immediately ready to use without extensive continuous maintenance when this hospital is inactive.

 

In our POC data management system, details of users, devices, cartridge lot numbers and results of control samples are available immediately. The POC coordinator gives, on a regular basis, feedback to the POC testing contact person at every clinical department on, for example, users, error codes and amount of measurements performed per user. There is no potential disadvantage of handheld devices getting lost by being out of sight in a user’s coat pocket because i-STAT-1 analysers are large enough to be noticed and always tend to be returned to their docking or recharging station.  

 

The LKCH has the services of a POC testing management team, consisting of a full-time POC testing coordinator, a clinical chemist with POC testing responsibility, the LKCH laboratory manager and a dedicated LIS specialist. For daily routine work, the LKCH relies on a POC team consisting of the POC coordinator and seven POC technicians. In contrast to the POC coordinator, the seven POC technicians alternately occupy one POC testing workplace (48 hours per week in total). The remaining hours of their employment are spent at the central laboratory. 

 

The POC team is responsible for user training, maintenance, troubleshooting, validation of every new cartridge/reagents shipment, standard operating procedures for different POC testing users and quality control (simulator, liquid controls, and monthly patient comparisons). Members of the POC testing team perform weekly on-site inspections, check if devices are contaminated, clean the device if necessary, and replenish cartridge/disposable stocks. 

 

In this way, they keep sight of all devices and their usage. The POC team is also responsible for training of each single POC user, always starting with a face-to-face instruction for both the pre-analytical handling of body fluid specimens and operation of the POC testing device. More than 2000 users have been trained in this way. To maintain users’ competence and for the purposes of recertification, a self-made e-testing program is used, dealing with important pre-analytical and handling aspects of different POC testing devices.

 

Conclusions

Management of POC testing in a large teaching hospital depends on a good POC team, a good POC data management system and, in our opinion, handheld POC devices with good analytical performance. All this will guarantee a robust POC testing testing facility, characterised by short turnaround times, small sample volumes and low risks of patient/sample identification errors.

 

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2. Kricka LJ, Thorpe GHG. Technology of handheld devices for point-of-care testing. In: Price CP, St John A, Kricka LJ (eds). Point-of-Care Testing: Needs, Opportunity, and Innovation, 3rd ed. Washington DC: AACC Press;2010:27–41.
3. Obladen M, Sachsenweger M, Stahnke M. Blood sampling in very low birth weight infants receiving different levels of intensive care. Eur J Pediatr 1988;147(4):399–404.
4. Madan A et al. Reduction in red blood cell transfusions using a bedside analyzer in extremely low birth weight infants. J Perinatol 2005;25(1):21–5.
5. Veldhoen ES et al. Analysis of bloodgas, electrolytes and glucose from intraosseous samples using an i-STAT((R)) point-of-care analyser. Resuscitation 2014;85(3):359–63.