American Society of Hirudotherapy

Systemic anticoagulation related to heparin locking of non-tunnelled venous dialysis catheters in intensive care patients

Research article published in Anaesthesia and intensive care (2016)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsBong et al. · Anaesthesia and intensive care, 2016

Abstract

Heparin locking of venous dialysis catheters is routinely performed in intensive care to maintain catheter patency when the catheters are not being used. Leakage of heparin into the circulation can potentially cause systemic anticoagulation and may present a risk to intensive care patients. To assess the effect of 5000 units per millilitre heparin locking of non-tunnelled dialysis catheters on systemic anticoagulation, we performed a prospective observational study of ten intensive care patients receiving heparin locking of dialysis catheters in an adult tertiary intensive care unit between July and September 2015. Activated partial thromboplastin time (APTT) was measured prior to, and three minutes after, heparin locking of catheter lumens with the manufacturer's recommended locking volume to assess the effect on systemic anticoagulation. Heparin locking of venous dialysis catheters resulted in a significant rise in APTT (P=0.002). The median rise was by 56 seconds (interquartile range 30-166.5). Following heparin locking, 80% of patients had APTT values within or above the range associated with therapeutic anticoagulation. Heparin locking of non-tunnelled venous dialysis catheters can cause systemic anticoagulation in intensive care patients and therefore poses a potential risk to patient safety.

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

Publication typeJournal Article
Indexed MeSH termsAdultAgedAnticoagulantsCathetersCritical CareFemaleHeparinHumansMaleMiddle AgedPartial Thromboplastin TimeProspective Studies

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This small prospective observational study of ten intensive-care patients found that heparin locking of non-tunnelled dialysis catheters caused a significant rise in APTT (P=0.002), with 80% of patients reaching APTT values within or above the therapeutic-anticoagulation range, indicating systemic heparin leakage and a potential safety risk. For the hirudotherapy narrative it serves as one more illustration of heparin's unpredictable systemic effects, reinforcing why locally acting, non-heparin anticoagulant approaches are of interest. The caveat is that this is a single small observational study (n=10) about catheter heparin locks, not about leeches or hirudin, so its relevance is purely as supporting context on heparin's limitations.

Citation

Systemic anticoagulation related to heparin locking of non-tunnelled venous dialysis catheters in intensive care patients.

Bong et al. · Anaesthesia and intensive care, 2016

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

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