title: Quantitative analysis of hemodynamics of congested island flaps under leech therapy.
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.
authors.affiliation: Department of Plastic and Reconstructive Surgery, the University of Tokushima Graduate School.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kashiwagi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hashimoto
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Abe
authors.forename: Kunio
authors.initials: K
authors.lastname: Kotsu
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamano
authors.forename: Hideki
authors.initials: H
authors.lastname: Nakanishi
mesh_terms: D000818:Animals; D001160:Arterioles / Q000473:pathology; D002245:Carbon Dioxide / Q000097:blood; D058752:Free Tissue Flaps / Q000098:blood supply* / Q000473:pathology; D006439:Hemodynamics; D024763:Leeching; D008833:Microcirculation; D010100:Oxygen / Q000097:blood; D011817:Rabbits; D014699:Venules / Q000473:pathology
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen