Comparison of the elution properties of commercially available gentamicin and bone cement containing vancomycin with 'home-made' preparations.

AIMS: Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available, but are significantly more expensive. We investigated whether the elution of antibiotic from 'home-made' cement containing vancomycin was comparable with more expensive commercially available vancomycin impregnated cement. MATERIALS AND METHODS: A total of 18 cement discs containing either proprietary CopalG+V; or 'home-made' CopalR+G with vancomycin added by hand, were made. Each disc contained the same amount of antibiotic (0.5 g gentamycin, 2 g vancomycin) and was immersed in ammonium acetate buffer in a sealed container. Fluid from each container was sampled at eight time points over a two-week period. The concentrations of gentamicin and vancomycin in the fluid were analysed using high performance liquid chromatography mass spectrometry. RESULTS: The highest peak concentrations of antibiotic were observed from the 'home-made' cements containing vancomycin, added as in the operating theatre. The overall elution of antibiotic was, fivefold (vancomycin) and twofold (gentamicin) greater from the 'home-made' mix compared with the commercially mixed cement. The use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. CONCLUSION: These findings suggest that the addition of 2 g vancomycin powder to gentamicin-impregnated bone cement by hand significantly increases the elution of both antibiotics compared with commercially prepared cements containing vancomycin. We found no significant advantages of using expensive commercially produced vancomycin-impregnated cement and recommend the addition of vancomycin powder by hand in the operating theatre. Cite this article: Bone Joint J 2017;99-B:73-7.

Survival of the Birmingham hip resurfacing in young men up to 13 years post-operatively.

The aim of this study was to determine the medium to long term survivorship of the Birmingham Hip Resurfacing prosthesis in an independent series of young men. The medical records and radiographs of all men aged 55 and under who had undergone Birmingham hip resurfacing by the senior author were reviewed. Patients who had not attended recent follow-up or had been previously discharged were contacted by telephone. Between 1999 and 2011 a total of 147 hips were resurfaced in 155 patients (mean age 47 years (19 to 55)) with minimum 5 year follow-up (mean 8.2, range 5 to 13.9 years). Eleven hips were revised giving overall cumulative survival of 88.8% at 13 years. In conclusion, this independent, single surgeon series demonstrates acceptable survival of the Birmingham Hip resurfacing in young men. It remains a valid option in certain cases but we believe alternative bearings are more suitable for most patients.

Impact of a blood management protocol on transfusion rates and outcomes following total hip and knee arthroplasty.

Introduction Preoperative anaemia remains undertreated in the UK despite advice from national agencies to implement blood conservation measures. A local retrospective audit of 717 primary hip/knee replacements in 2008-2009 revealed 25% of patients were anaemic preoperatively. These patients experienced significantly increased transfusion requirements and length of stay. We report the results of a simple and pragmatic blood management protocol in a district general hospital. Methods Since 2010 patients at our institution who are found to be anaemic when listed for hip/knee replacement have been offered iron supplementation and/or erythropoietin depending on haemoglobin and ferritin levels. In this study, postoperative blood transfusions, length of stay and readmissions were assessed retrospectively for all patients undergoing elective primary hip/knee replacement in 2014 and compared with the baseline findings. Results During the 12-month study period, 406 patients were eligible for inclusion and none were excluded. Eighty-nine patients (22%) were anaemic preoperatively and sixty-five received treatment. The transfusion rate fell from the baseline levels of 23.0% and 6.7% to 4.3% and 0.5% for hip and knee replacements respectively (p<0.001). The median length of stay reduced from 6 to 3 days (p<0.001) for both hip and knee replacements. The rate for readmissions within 90 days fell from 13.5% to 8.9% (p<0.05). Conclusions Preoperative anaemia is common in patients listed for hip/knee replacement and it is associated strongly with increased blood transfusion. The introduction of a blood management protocol has led to significant reductions in transfusion and length of stay, sustained over a four-year period. This suggests that improved patient outcomes, conservation of blood stocks and cost savings can be achieved.