American Society of Hirudotherapy

Free Flap Perfusion in Microvascular Head and Neck Reconstruction: Influence of the Number of Ischemia Intervals and Ischemia Duration-A Retrospective Study

Research article published in Journal of otolaryngology - head & neck surgery = Le Journal d'oto-rhino-laryngologie et de chirurgie cervico-faciale (2024)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsOoms et al. · Journal of otolaryngology - head & neck surgery = Le Journal d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 2024

Abstract

BACKGROUND: In microvascular head and neck reconstruction, ischemia of the free flap tissue is inevitable during microsurgical anastomosis and may affect microvascular free flap perfusion, which is a prerequisite for flap viability and a parameter commonly used for flap monitoring. The aim of this study was to investigate the influence of the number of ischemia intervals and ischemia duration on flap perfusion. METHODS: Intraoperative and postoperative flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation at 2 and 8 mm tissue depths, as measured with the O2C tissue oxygen analysis system, were retrospectively analyzed for 330 patients who underwent microvascular head and neck reconstruction between 2011 and 2020. Perfusion values were compared between patients without (control patients) and with a second ischemia interval (early or late) and examined with regard to ischemia duration. RESULTS: Intraoperative and postoperative flap blood flow at 8 mm tissue depth were lower in patients with early second ischemia intervals than in control patients [102.0 arbitrary units (AU) vs 122.0 AU, P = .030; 107.0 AU vs 128.0 AU, P = .023]. Both differences persisted in multivariable analysis. Intraoperative and postoperative flap blood flow at 8 mm tissue depth correlated weakly negatively with ischemia duration in control patients (r = -.145, P = .020; r = -.124, P = .048). Both associations did not persist in multivariable analysis. CONCLUSIONS: The observed decrease in microvascular flap blood flow after early second ischemia intervals may reflect ischemia-related vascular flap tissue damage and should be considered as a confounding variable in flap perfusion monitoring.

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

Publication typeJournal Article
Indexed MeSH termsHumansFree Tissue FlapsRetrospective StudiesMaleFemaleMiddle AgedPlastic Surgery ProceduresHead and Neck NeoplasmsAgedIschemiaMicrosurgeryAdult

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

In this retrospective study of 330 head-and-neck free-flap patients, intraoperative and postoperative flap blood flow at 8 mm depth were lower in flaps subjected to an early second ischemia interval (e.g., 102.0 vs 122.0 arbitrary units, P = .030), a difference that persisted on multivariable analysis, leading the authors to conclude that repeated early ischemia may reflect vascular tissue damage and should be treated as a confounder in perfusion monitoring. This is relevant to hirudotherapy because medicinal leeches are used specifically to relieve venous congestion and improve outflow in struggling flaps, and the study underscores how sensitively flap perfusion responds to ischemic insult. Honest caveat: the study characterizes perfusion physiology and monitoring; it does not evaluate leech therapy and does not address whether leeching alters flap-flow outcomes.

Citation

Free Flap Perfusion in Microvascular Head and Neck Reconstruction: Influence of the Number of Ischemia Intervals and Ischemia Duration-A Retrospective Study.

Ooms et al. · Journal of otolaryngology - head & neck surgery = Le Journal d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 2024

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

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