Quantitative analysis of hemodynamics of congested island flaps under leech therapy
Research article published in The journal of medical investigation : JMI (2013)
Abstract
BACKGROUND: A congested flap is a good indication for leech therapy. However, determining the appropriate number of leeches as well as the appropriate application time in clinical cases is difficult. We analyzed hemodynamics in rabbit island flaps under leech therapy to find a suitable clinical procedure for determining the appropriate number of leeches to be used and the duration of therapy. METHODS: Island flaps were raised in 35 rabbit ears, and congestion was induced by venous clamping. Treatment involved use of 1 or 3 leeches and was begun 60 minutes after venous occlusion. Flaps were examined for area of surviving tissue, alterations in transcutaneous oxygen and carbon dioxide tension (TcPO2 and TcPCO2), and flow volume. Arteriole and venule diameters and flow velocities were examined microscopically. RESULTS: Flap survival area in the 3-leech therapy group was significantly larger than the 1-leech therapy group and the control group. With 3-leech therapy, TcPCO2 decreased significantly, as did arteriole and venule diameters. After clamp release, TcPCO2 and venule diameter continued to decrease in this group, and flow velocity increased significantly. CONCLUSIONS: Leech therapy may salvage compromised flaps by replacing congested blood with new arterial blood and thus maintaining flap viability. TcPO2 and TcPCO2 monitoring may help evaluate the therapeutic effect and determine the appropriate number of leeches to apply and the duration of therapy.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
A congested flap is a good indication for leech therapy.
Why This Matters for Hirudotherapy
This study quantitatively analyzed hemodynamics, tissue survival, and blood gas tensions in experimentally induced congested island flaps in rabbit ears under leech therapy to determine the optimal number of leeches and duration of treatment. The findings are directly relevant to hirudotherapy, demonstrating that three leeches significantly improved flap survival area and decreased carbon dioxide tension compared to one leech, with flow velocity increasing significantly within the three-leech group after clamp release. However, this is an animal model using experimentally induced flap congestion. Clinical translation of these specific hemodynamic parameters and leech quantities requires validation in human patients before standardizing procedural guidelines.
Citation
Quantitative analysis of hemodynamics of congested island flaps under leech therapy
Kashiwagi K et al. · The journal of medical investigation : JMI, 2013
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