2430
Switching Haemodialysis Catheter Locks to Citrate: A Safety and Efficacy Study
Prince J, Bubtana A, Subbegowda J, Hughes S, Thomas S, Howard L, Deaville M, Ebah L, Mitra S
Department of Renal Medicine, Central Manchester University Hospitals NHS Foundation Trust
Background
Citrate line locks for haemodialysis (HD)catheters have been shown to offer equivalent anticoagulation to heparin with additional benefits such as anti-biofilm and anti-microbial properties. Their use however saw a significant decline in the early 2000s after an FDA warning regarding use of citrate 46.7% solution. Subsequent studies with 4% and 30% citrate have allayed these concerns; there has been a resurgence of citrate locks. This study piloted the feasibility, efficacy and safety of switching of HD catheter line locks from heparin to citrate.
Methods
Citralock® 30% was the chosen citrate lock. Heparin 5000 units/ml was previously used as catheter lock solution in all patients with catheters. Two cohorts of patients were identified in two HD satellite units and their informed consent obtained.In one satellite unit (Unit A), a sequential approach was used, comparing the 12 HD sessions before Citralock switch to the 12 sessions after the switch in the same patients, whilst in the other unit (Unit B), a parallel random assignment to Citralock® or heparin was done and the comparative effects studied over 27 HD sessions. All staff received training on the administration of Citralock® and a protocol was produced. HD blood flow rates, arterial and venous pressures, the need for thrombolytic therapy and any adverse events were recorded in both groups during the study period.
Results
In total, 30 patients were switched to Citralock® (11 in Unit A and 19 in Unit B) whilst 21 patients remained in the heparin lock arm (11in Unit A and 10 in Unit B). The use of thrombolytic therapy was required 19 times out of the 402 sessions (5%) in the heparin group compared to 7 times out of the 645 sessions(1%) in the Citralock® group (p=0.0004). The relative risk for needing thrombolytic therapy with heparin compared to Citralock® was 4.4[1.8-10.3]. There were four (20%) line infections in the heparin group patientscompared to one (3%) in the Citralock® group (p=0.15). There was no difference between mean effective blood flows (265.5 in the heparin group compared to 267.7 in the Citralock® group; p=0.78) and mean venous pressures (175.8 vs 177.1 respectively; p=0.87). No catheter removal or admission for infection or line removal. One patient (3%) in the Citralock® arm complained of transient peri-oral paraesthesiae. This patient had lowserum corrected calcium of 1.9mmol/L prior to Citralock® administration. The equivalent costs were £3088 for heparin and £747 for Citralock®. The staff found Citralock easy to use.
Conclusion
The pilot study demonstrates that Citralock® 30% HD catheter locks are safe to use, and provide effective catheter anticoagulation. Use of Citralock® 30% seemed to strongly reduce the need for thrombolytic therapy. The study strengthened our confidence in the use of Citralock® 30% which is currently being rolled out to all our HD units.