Impact of sodium bicarbonate locking solution on catheter-related blood stream infection in hemodialysis patients: comparative effectiveness of three locks.

Background: The primary challenge for hemodialysis (HD) patients using permanent tunneled cuffed catheters is to prevent catheter-related bloodstream infections. This study assessed the effectiveness of sodium bicarbonate in preventing catheter-related bloodstream infections and compared its efficacy to antibiotic-containing locks.

Design, materials, and methods: We conducted a prospective single-center, open-label, cohort study over 30 months with the aim to compare three cohorts: cohort I employed 8.4% sodium bicarbonate solution lock, cohort II employed 0.5 mg/ml gentamicin/acid citrate dextrose solution lock, and cohort III employed unfractionated conventional heparin 5000 U/ml solution lock. The primary endpoint was the first episode of catheter-related bloodstream infection, while the secondary endpoint was catheter loss due to catheter-related bloodstream infection.

Results: This study involved 204 HD patients with permanent tunneled cuffed central venous catheters (CVCs). A total of 58 cases of catheter-related bloodstream infection were documented. In the sodium bicarbonate-lock cohort, infection occurred in 17.24%, in the gentamicin/acid citrate-lock cohort in 36.21%, and in the heparin-lock cohort in 46.55%. Patients with sodium bicarbonate and gentamicin/acid citrate locks exhibited a statistically significant lower risk of developing infections (0.4/1000 catheter days and 0.7/1000 catheter days, respectively) compared to patients with heparin-lock (1.4/1000 catheter days). Patients with heparin lock faced a higher risk of losing a catheter due to infection compared to those with gentamicin/acid citrate lock and sodium bicarbonate-lock (Hazard Ratio (HR) = 1.26, 95% Confidence Interval (CI) [1.09-1.46], P = 0.001) and (HR = 1.10, 95% CI [1.01-1.19], P = 0.024).

Conclusion: The sodium bicarbonate locking solution demonstrated an infection-free catheter survival comparable to that of the gentamicin citrate solution and significantly decreased catheter-related bloodstream infection compared to heparin locks.