American Society of Hirudotherapy

Dextran-related complications in head and neck microsurgery: do the benefits outweigh the risks? A prospective randomized analysis.

Randomized controlled trial published in Plastic and reconstructive surgery (2003)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Randomized controlled trialClinical TrialsDrug DevelopmentDisa et al. · Plastic and reconstructive surgery, 2003

Abstract

Increased experience with free-tissue transfer has minimized flap loss secondary to microvascular thrombosis, yet pharmacologic antithrombotic prophylaxis continues to be used routinely. Currently there is no consensus on the ideal pharmacologic agent, dosing, or efficacy. Low-molecular-weight dextran has been widely used for prophylaxis due to its properties of volume expansion and enhanced microrheology. Significant systemic morbidity (pulmonary morbidity, cardiac morbidity, anaphylaxis) is known to occur with use of low-molecular-weight dextran. The purpose of this study was to evaluate morbidity associated with postoperative low-molecular-weight dextran and aspirin prophylaxis in head and neck microsurgery patients. This study was a randomized prospective analysis of 100 consecutive patients undergoing microvascular reconstruction for head and neck malignancy during a 2-year period. Patients were randomized into one of three postoperative antithrombotic prophylaxis treatment groups: low-molecular-weight dextran 20 cc/hour for 48 hours (n = 35), low-molecular-weight dextran 20 cc/hour for 120 hours (n = 32), or aspirin 325 mg/day for 120 hours (n = 27). Six patients were excluded intraoperatively due to the need for systemic heparin therapy. Treatment groups were compared for age, sex, prior medical problems, duration of anesthesia, and intraoperative fluid intake. Flap outcome and the incidence of local and systemic complications were evaluated in the treatment groups. Patient ages ranged from 12 to 84 years (mean age, 58 years). No significant difference was found among the treatment groups with respect to age, sex, prior medical problems, duration of anesthesia, intraoperative fluid intake, and the distribution of donor and recipient sites. There were no total flap losses and two partial flap losses in this series. Three flaps were reexplored and all were salvaged. The incidence of systemic complications (congestive heart failure, myocardial infarction, pulmonary edema, pleural effusion, and pneumonia) was as follows: low-molecular-weight dextran 120 hours, 51 percent; low-molecular-weight dextran 48 hours, 29 percent; and aspirin, 7 percent. Analysis of these data suggests that the method of prophylaxis had no effect on overall flap survival. However, the incidence of systemic complications was significantly related to the method of prophylaxis, with patients receiving low-molecular-weight dextran 120 hours and 48 hours at a 7.2 and 3.9 times greater relative risk, respectively, of developing a systemic complication compared with patients receiving aspirin. The results of this study have eliminated the routine use of low-molecular-weight dextran prophylaxis at our institution in an effort to reduce morbidity in head and neck microsurgical reconstruction.

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

Publication typeClinical TrialJournal ArticleRandomized Controlled Trial
Indexed MeSH termsAdolescentAdultAgedAged, 80 and overAnticoagulantsAspirinChildDextransFemaleHead and Neck NeoplasmsHumansMale

Summary

Increased experience with free-tissue transfer has minimized flap loss secondary to microvascular thrombosis, yet pharmacologic antithrombotic prophylaxis continues to be used routinely. Currently there is no consensus on the ideal pharmacologic agent, dosing, or efficacy.

Why This Matters for Hirudotherapy

This randomized prospective trial compared morbidity associated with low-molecular-weight dextran versus aspirin for postoperative antithrombotic prophylaxis in 100 head and neck microsurgery patients across three treatment groups. The study found no total flap losses and no significant difference in flap survival among groups, but systemic complication rates were 51% with 120-hour dextran, 29% with 48-hour dextran, and 7% with aspirin, translating to 3.9–7.2 times greater relative risk with dextran versus aspirin. These results led the institution to discontinue routine dextran prophylaxis. CAVEAT: This study involves no leeches, hirudin, hirudotherapy, or leech-derived compounds whatsoever, and no defensible leech link to ASH's domain exists.

Citation

Dextran-related complications in head and neck microsurgery: do the benefits outweigh the risks? A prospective randomized analysis.

Disa et al. · Plastic and reconstructive surgery, 2003

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

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