1768
REDUCING HAEMODIALYSIS BACTERAEMIA RATES
Murray E.C., Deighan C., Geddes C., Thomson P.C.
Renal Unit, Western Infirmary, Dumbarton Road, Glasgow, G11 6NT
INTRODUCTION: Infection is the second-highest cause of death among renal replacement therapy patients, accounting for approximately 20% of mortality. Up to 90% of bacteraemias in the haemodialysis (HD) population are staphylococcal, supporting vascular access as the primary source and driver of infection. Preventing infection-related deaths on HD therefore requires: (i) optimal vascular access with an arteriovenous fistula (AVF) or graft (AVG), as opposed to tunnelled or non-tunnelled central venous catheter (TCVC / NTCVC); and (ii) reducing the prevailing bacteraemia rate. In this study we describe the effect of introducing catheter lock solution taurolidine-citrate heparin (TauroHep500©) in TCVCs, and chlorhexidine impregnated exit-site patch (Biopatch©) in NTCVCs on prevailing staphylococcal bloodstream infection rates.
METHODS: The quarterly incidence rates of all staphylococcal bacteraemic events in the NHS Greater Glasgow & Clyde and NHS Forth Valley HD population were collected April 2011 to June 2013. This was achieved by a structured query language interrogation of the renal unit electronic patient record with the resulting output being processed by Microsoft Office Excel 2003. Consecutive blood culture results >14 days apart were regarded as separate events. Vascular access data were cross-checked by hand. Event rates were expressed as events per 1000 HD-exposed days for each vascular access type. Comparison between periods was made by student’s t-testing with a significance level set at a<0.05.
RESULTS: 261 staphylococcal bacteraemia events occurred over 427,836 HD days during the study period. Comparing the rate before and after the introduction of TauroHep500 in TCVCs demonstrated a reduction from 1.58/1000 HD days (95% confidence interval [CI] 1.12, 2.03) to 0.74/1000 HD days (95% CI 0.20, 1.28), p<0.01. In NTCVCs no change in staphylococcal bacteraemia rates was observed; 6.06/1000 HD days (95% CI 3.43, 8.71) pre-Biopatch, 10.36/1000 HD days (95% CI 3.10, 17.62) following introduction, p=0.10. The staphylococcal bacteraemia rate in AVF/AVGs remained unchanged; 0.28/1000HD days pre-July 2012 (95% CI 0.16, 0.41) versus 0.27/1000 HD days post-July 2012 (95% CI 0.18, 0.36), p=0.87.
CONCLUSION: Chlorhexidine-impregnated foam patches on NTCVC exit sites failed to demonstrate any reduction in staphylococcal bacteraemia rates, though cumulative HD days and incidence events were too low to detect a small effect size. Replacing heparin 5000iU/mL with TauroHep500 as catheter lock solution in patients with TCVCs was associated with a statistically significant 47% reduction in staphylococcal bloodstream infection rates.