American Society of Hirudotherapy

Low dose heparin lock (1000 U/mL) maintains tunnelled hemodialysis catheter patency when compared with high dose heparin (5000 U/mL): A randomised controlled trial.

Randomized controlled trial published in Hemodialysis international. International Symposium on Home Hemodialysis (2016)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Randomized controlled trialClinical TrialsDrug DevelopmentChu et al. · Hemodialysis international. International Symposium on Home Hemodialysis, 2016

Abstract

Introduction Heparin is commonly used after hemodialysis treatments as a locking solution to prevent catheter thrombosis. The comparative efficacy and safety of different heparin concentrations to maintain catheter patency has been previously reported in retrospective studies. We conducted a prospective, randomised, controlled study of 1000 U/mL heparin (low dose) versus 5000 U/mL heparin (high dose) locking solution to maintain patency of tunnelled catheters. Methods One hundred patients receiving chronic, unit-based hemodialysis with newly placed tunnelled hemodialysis catheters (less than 1 week) were randomly assigned to either a low dose (n = 48) or high dose heparin (n=52). The primary intention-to-treat analysis examined time to malfunction in both groups over a 90 day period. A secondary analysis compared baseline patient characteristics in relation to catheter malfunction. Findings Overall rate of catheter patency loss was 32% of catheters by 90 days. There was no significant difference in time to malfunction of catheters locked with low dose or high dose heparin (P = 0.5770). Time to catheter malfunction was not associated with diabetic, hypertensive or smoking status. There was no difference in mean delivered blood flow rate, venous and arterial pressure, and dialysis adequacy between low dose and high dose groups. No patient suffered a hemorrhagic complication requiring hospitalisation during the study period. Discussion Low dose heparin is adequate to maintain tunnelled hemodialysis catheter patency when compared with high dose heparin. The study also suggests that there is no relationship between catheter malfunction and diabetic, hypertensive or smoking status.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeComparative StudyJournal ArticleRandomized Controlled Trial
Indexed MeSH termsAdultAgedAged, 80 and overAnticoagulantsCentral Venous CathetersFemaleHeparinHumansMaleMiddle AgedProspective StudiesRenal Dialysis

Summary

Introduction Heparin is commonly used after hemodialysis treatments as a locking solution to prevent catheter thrombosis. The comparative efficacy and safety of different heparin concentrations to maintain catheter patency has been previously reported in retrospective studies.

Why This Matters for Hirudotherapy

This randomized controlled trial compared low-dose (1000 U/mL) versus high-dose (5000 U/mL) heparin as locking solutions for tunnelled hemodialysis catheters in 100 patients over 90 days, finding no significant difference in time to catheter malfunction, delivered blood flow rates, dialysis adequacy, or hemorrhagic complications between groups. The authors conclude that low-dose heparin is adequate for maintaining catheter patency. For ASH's domain, this study addresses anticoagulant lock solution dosing for catheter maintenance, a topic within clinical anticoagulation practice. However, the study contains no reference to leeches, hirudotherapy, or the leech secretome, and any relevance to ASH's domain is limited to the general context of heparin use without a defensible leech-related connection.

Citation

Low dose heparin lock (1000 U/mL) maintains tunnelled hemodialysis catheter patency when compared with high dose heparin (5000 U/mL): A randomised controlled trial.

Chu et al. · Hemodialysis international. International Symposium on Home Hemodialysis, 2016

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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