Cathasept line lock and microbial colonization of tunneled hemodialysis catheters: A multicenter randomized controlled trial

Abstract

Background Catheter-related bloodstream infections (CRBSIs) cause morbidity and mortality in hemodialysis (HD) patients. Cathasept (tetra-sodium EDTA) solution has antimicrobial and anticoagulant activities. Study Design Multicenter prospective randomized controlled study. Setting & Participants 117 maintenance HD patients with confirmed uncolonized tunneled HD catheters from 4 HD centers. Intervention Patients were randomly assigned to receive Cathasept 4% locks (Cathasept group) or stayed with heparin 5,000 U/mL locks (heparin group), filled thrice weekly according to catheter lumen volume until the catheter was removed or for a maximum of 8 months. Outcomes Primary outcome was clinically significant microbial colonization of the catheter, defined as a through-catheter quantitative blood culture yielding ≥ 1,000 colony-forming units/mL of bacteria or yeast. Secondary outcomes included CRBSI rate, catheter patency, and biomarkers of inflammation and anemia. Measurements Weekly through-catheter quantitative blood culture, high-sensitivity C-reactive protein fortnightly, and full blood count and ferritin monthly. Results Incidence rates of catheter colonization were 0.14/1,000 catheter-days in the Cathasept group and 1.08/1,000 catheter-days in the heparin group (incidence rate ratio [IRR], 0.13; 95% CI, 0.003-0.94; P = 0.02). CRBSI rates were 0.28/1,000 catheter-days in the Cathasept group and 0.68/1,000 catheter days in the heparin group (IRR, 0.40; 95% CI, 0.08-2.09; P = 0.3). The proportion of dialysis sessions with achieved prescribed blood flow rate was significantly lower in the Cathasept group (66.8% vs 75.3%; P < 0.001), with more patients requiring thrombolytic locks or infusions to maintain catheter patency (22 vs 9; P = 0.01). Mean high-sensitivity C-reactive protein level was 11.6 ± 5.3 (SE) mg/L lower for patients in the heparin group (P = 0.03). Anemia marker levels were similar in both groups. Limitations Study was underpowered to assess effect on CRBSI, terminated early due to slow recruitment, and not double blinded. Conclusions Cathasept significantly reduced tunneled hemodialysis catheter colonization, but the reduction in CRBSIs was not statistically significant, and it was associated with more thrombotic complications. Its safety profile was comparable to heparin lock solution.