Evaluation of clinically applicable exsanguination treatments to alleviate venous congestion in an animal skin flap model
Experimental study published in Wound Repair Regen (1999)
Abstract
This study compares the effectiveness of alleviating venous congestion with mechanically-made outlets or leech therapy in promoting skin flap survival. Free flaps of abdominal skin (3 x 6 cm) were raised on Sprague-Dawley rats and subjected to ischemic events, simulating venous congestion. Animals received 1) no treatment; 2) two treatments involving two 18-gauge needle-puncture outlets; or 3) two sessions of leech therapy. Flap perfusion was monitored with a scanning laser Doppler flowmeter. Photographic images of flaps at 7 days were assessed for areas of normal tissue (n = 15), and laser Doppler flowmeter data consisted of control (n = 6), outlet (n = 6), and leech (n = 7). Both the needle-puncture outlet (40.0% +/- 9.24%) and leech treated (34.6% +/- 7.34%) groups had a significantly greater surviving skin area than untreated control flaps (8.0% +/- 5.0%), with 2 of 15 flaps receiving mechanical outlets exhibiting > 90% surviving area. After 7 days, laser Doppler flowmeter data showed greater mean perfusion in the outlet (71.7% +/- 16.8%) and leech (92.6% +/- 17.2%) treated groups, compared to controls (15.2% +/- 10.2%). There was a significant increase in perfusion in the outlet (13.3% +/- 6.2%) and leech (9.1% +/- 1.1%) treated groups from the end of secondary ischemia to day 7 (p < 0.05) compared to controls. The results suggest that two spatially separated outlets are as effective as one leech in increasing the area of surviving skin in venous congested flaps.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Two needle-puncture outlets and leech therapy each significantly improved skin flap survival versus controls (40% and 35% vs 8%) in venous congested rat skin flap model.
Why This Matters for Hirudotherapy
This comparative animal study used a rat skin flap model (3×6 cm abdominal flaps) to evaluate needle-puncture outlets versus leech therapy for venous congestion. Both treatments significantly improved 7-day surviving skin area (outlets 40.0%, leeches 34.6%) compared to untreated controls (8.0%), and both increased perfusion versus controls. The authors concluded that two spatially separated mechanical outlets were as effective as a single leech. This study is directly relevant to ASH as it provides preclinical comparative data on leech therapy efficacy in flap salvage. However, it is an animal model with small sample sizes (n=6–7 per group for perfusion data), limiting direct clinical translation.
Citation
Evaluation of clinically applicable exsanguination treatments to alleviate venous congestion in an animal skin flap model.
Cottler PS et al. · Wound repair and regeneration, 1999
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