Nobels F, Beckers F, Bailleul E, De Schrijver P, Sierens L, Van Crombrugge P
Department of Endocrinology, O.L. Vrouwziekenhuis, Aalst, Belgium.
Diabet Med. 2004 Dec;21(12):1288-91. doi: 10.1111/j.1464-5491.2004.01333.x.
Description of the long-term use of a quality assurance (QA) programme for bedside capillary blood glucose (CBG) testing in a general hospital.
The main points of the programme were selection of instrumentation using a standardized testing procedure, design and implementation of a quality control (QC) procedure, and training and motivation of nurses. The QC procedures consisted of a daily aqueous control and a weekly split-sample control (a measurement on a capillary blood sample using the glucose meter and on a simultaneously drawn venous sample with the laboratory analyser). When the result was out of range, a laboratory technician visited the ward to investigate the problem. All wards received a weekly report.
The programme was introduced in 1995 and followed up through 2002. The split-sample control was more efficient in detecting clinically relevant errors than the aqueous control. Most errors (91-97%) were operator-related rather than instrument-related. The compliance with the split-sample controls remained high, with 84-91% of weekly controls performed over 7 years. Respectively 91, 95 and 96% of the measurements remained within the range of +/- 20% of the laboratory value in the years 2000, 2001 and 2002.
A QA programme of bedside CBG testing can successfully be implemented. It is feasible to obtain a satisfying level of measurement accuracy and to maintain a high level of compliance with the programme over several years. Split-sample controls are an essential part of the control procedure.