Feasibility of a quality assurance programme of bedside blood glucose testing in a hospital setting: 7 years' experience.

AIMS: Description of the long-term use of a quality assurance (QA) programme for bedside capillary blood glucose (CBG) testing in a general hospital. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Remarkable removal of beta-2-microglobulin by on-line hemodiafiltration.

UNLABELLED: Eight chronic, anuric hemodialysis patients were randomly treated with a high-flux polysulphone dialyzer (F80), using 6 different modes: conventional bicarbonate hemodialysis (HD), hemodiafiltration (HDF) with a replacement solution at 40, 60, 80 or 100 ml/min in postdilution and 80 ml/min in predilution. The differences in beta 2-microglobulin (beta 2M) reduction ratio and clearance were evaluated statistically by analysis of variance (ANOVA). Both studies revealed no significant difference between HD and HDF40 in postdilution, but an increasing significant difference from HDF60 to HDF100 in postdilution and with HDF80 in predilution. The mean reduction ratio ranged from 49.7 (HD) to 72.7% (HDF 100 ml/min), showing an overall statistically significant difference (p = 0.0000). For the clearance, the range was between 63.8 (HD) and 116.8 ml/min (HDF 100 ml/min) (p = 0.0000). beta 2M in the effluent dialysate with HDF 100 ml/min reached up to a mean of 258 mg/session. Concerning small molecules (BUN, creatinine and P), there was a statistically significant different clearance for creatinine and especially for P with HDF 100 ml/min. CONCLUSION: HDF with an on-line replacement solution at 100 ml/min and a high-flux and biocompatible polysulphone membrane represents a new tool for enhanced removal of beta 2M. Besides a significant increase in creatinine and especially in phosphorus clearance is noted.

On-line haemodiafiltration. Remarkable removal of beta2-microglobulin. Long-term clinical observations.

BACKGROUND: The accumulation of beta2-microglobulin (beta2-M) in long-term dialysis patients may lead to dialysis amyloidosis. In this respect, the removal with different modes of on-line haemodiafiltration (HDF) of beta2-M was studied. Long-term clinical observations in patients with more than 10 years of dialysis, treated mainly with biocompatible and highly permeable membranes and in the last years with on-line HDF are also reported. METHODS: In the first part of this report, the reduction ratios and clearances of beta2-M, blood urea nitrogen, creatinine and phosphorus (P) of on-line HDF with 40 to 120 ml/min replacement fluid are compared with bicarbonate haemodialysis (HD). In the second part, we investigated 16 patients with more than 10 years of dialysis treatment. The prevalence of dialysis amyloidosis and the mean values for serum albumin, serum total cholesterol, HDL and LDL cholesterol and parathyroid hormone are reported, as well as the mean dose of erythropoietin. RESULTS: In the first part with on-line HDF, starting from HDF 60 ml/min a significantly higher beta2-M reduction ratio and clearance vs HD is noted. In HDF100 (i.e. with 241 replacement volume per 4-h treatment) vs HD, a beta2-M reduction ratio of 72.7% vs 49.7% (P= 0.0000) and a beta2-M clearance of 116.8 vs 63.8 ml/min (P=0.0000) was obtained. Comparing HDF120 with HDF100, there is a significantly higher beta2-M clearance with the former (P<0.005), although the beta2-M reduction ratio was not significantly better. In the HDF120 session the amount of beta2-M in the total dialysate was 292 mg per session. If one adds the known 17% adsorption on the polysulfone membrane, a total of 341.6 mg beta2-M per session is removed, which adds up to 1024.8 mg a week. Concerning the small molecules, our results with HDF100 also show a higher creatinine and especially P clearance vs HD. In the second part with 16 patients with more than 10 years of dialysis treatment (mean 14 years 1 month), the mean time on HDF amounted to 39.5% of the total treatment time. In four patients only biocompatible and highly permeable membranes were used, AN69 and mainly polysulfone, and in four other patients these membranes were used for more than 95% of the treatment time. Therefore, it is not surprising that the prevalence of carpal tunnel syndrome was only 12.5% in the patients after 10 years of dialysis. Twenty-five percent of these patients met the criteria for diagnosis of beta2-M bone-amyloidosis, proposed by van Ypersele de Strihou et al., but without a retrospective X-ray analysis. The mean predialysis beta2-M value was 29.6 mg/l. The mean values for serum albumin, serum total cholesterol, HDL and LDL cholesterol were within normal limits. For the parathyroid hormone a mean of 287.5 pg/ml was found. Subtotal parathyroidectomy was performed in five patients. The mean dose of 43 U erythropoietin/kg per session is comparable with those reported in the literature. Conclusions. Like Canaud, in our renal unit, treatment with on-line HDF with a highly permeable and biocompatible membrane has proven to be an efficient, well-tolerated and safe technique. Furthermore it leads to a low prevalence of dialysis amyloidosis and a superior P clearance. However, continuous attention must be paid to an on-line sterile and apyrogenic dialysate. Although on-line HDF is undoubtedly a more optimal approach of chronic dialytic treatment, it also carries a higher cost, which is currently evaluated to be nearly US$11 per session.