Mateusz Gładysz FESSH prep

FESSH prep Microsurgery End to end versus end to side anastomosis, venous and arterial coupler devices, postoperative antithrombotics, dextran

Microvascular anastomosis: technique, couplers and antithrombotic prophylaxis

Last reviewed v1.0

FESSH-060Microsurgery●●○ intermediate

Regarding microvascular anastomosis in free-tissue transfer:

  1. 1.Meta-analysis shows no significant difference in thrombosis or flap failure between end-to-end and end-to-side arterial anastomoses.

  2. 2.Venous coupler devices shorten anastomosis time compared with hand-sewn venous anastomosis without increasing the rate of venous thrombosis.

  3. 3.Meta-analysis shows that anastomotic coupler devices used for arteries significantly reduce arterial thrombosis compared with hand-sewn arterial anastomosis.

  4. 4.Pooled analyses show that routine postoperative antithrombotic agents do not reduce total flap loss after free-tissue transfer.

  5. 5.In a randomised trial in head and neck microsurgery, low-molecular-weight dextran improved flap survival compared with aspirin, with a similar rate of systemic complications.

FESSH marking: +1 per correct statement, 0 for blank, −1 for incorrect. Click the same TRUE/FALSE button twice to clear it.

Question ID
FESSH-060
First published
Last reviewed
Version
v1.0
Answer key and explanations — open after answering

  1. 1. Meta-analysis shows no significant difference in thrombosis or flap failure between end-to-end and end-to-side arterial anastomoses.

    True

    Ahmadi's meta-analysis found marginal and non-significant differences in thrombosis and flap failure between end-to-end and end-to-side venous and arterial anastomoses (arterial relative risks 1.04 for both outcomes). Khouri's prospective multicentre study also found that end-to-end versus end-to-side arterial technique did not affect flap outcome.

    • Ahmadi I, Herle P, Miller G, Hunter-Smith DJ, Leong J, Rozen WM. End-to-End versus End-to-Side Microvascular Anastomosis: A Meta-analysis of Free Flap Outcomes. J Reconstr Microsurg. 2017;33(6):402-411. PMID 28259112
    • Khouri RK, Cooley BC, Kunselman AR, Landis JR, Yeramian P, Ingram D, et al.. A prospective study of microvascular free-flap surgery and outcome. Plast Reconstr Surg. 1998;102(3):711-21. PMID 9727436

  2. 2. Venous coupler devices shorten anastomosis time compared with hand-sewn venous anastomosis without increasing the rate of venous thrombosis.

    True

    Maruccia's meta-analysis found that the coupler significantly reduced anastomotic time and flap failure but did not change venous thrombosis risk; Costantino's head and neck meta-analysis found no difference in venous thrombosis (odds ratio 1.06), and in that analysis the shorter anastomosis time with the coupler was not statistically significant. The underlying studies are observational, so 'equivalent patency, shorter time' is the safe summary.

    • Maruccia M, Fatigato G, Elia R, Ragusa LA, Vestita MG, Nacchiero E, et al.. Microvascular coupler device versus hand-sewn venous anastomosis: A systematic review of the literature and data meta-analysis. Microsurgery. 2020;40(5):608-617. PMID 32246807
    • Costantino A, Uralov D, Festa BM, Pace GM, Alamoudi U, Haughey B, et al.. Microvascular Coupling in Venous Anastomoses for Head and Neck Reconstruction: A Systematic Review and Meta-Analysis. Otolaryngol Head Neck Surg. 2025;172(5):1548-1559. PMID 39981870

  3. 3. Meta-analysis shows that anastomotic coupler devices used for arteries significantly reduce arterial thrombosis compared with hand-sewn arterial anastomosis.

    False

    Wang's meta-analysis of arterial anastomosis in head and neck free flaps found that the device group tended towards more arterial thrombosis and vascular compromise (risk ratio 3.42, 95% confidence interval 0.91–12.77), a non-significant difference. The authors concluded that the devices might increase, not reduce, the risk of arterial thrombosis, pending randomised trials.

    • Wang YJ, Wang XL, Jin S, Zhang R, Gao YQ. Meta-analysis of arterial anastomosis techniques in head and neck free tissue transfer. PLoS One. 2021;16(4):e0249418. PMID 33793654

  4. 4. Pooled analyses show that routine postoperative antithrombotic agents do not reduce total flap loss after free-tissue transfer.

    True

    Lee and Mun's meta-analysis found that antithrombotics did not reduce total flap loss (relative risk 0.99) or thrombosis (1.00) but increased haematoma (1.78); aspirin raised haematoma risk significantly. Dawoud found that therapeutic-dose anticoagulation in head and neck free flaps increased haematoma and bleeding needing intervention without reducing flap failure.

    • Lee KT, Mun GH. The efficacy of postoperative antithrombotics in free flap surgery: a systematic review and meta-analysis. Plast Reconstr Surg. 2015;135(4):1124-1139. PMID 25811576
    • Dawoud BES, Kent S, Tabbenor O, Markose G, Java K, Kyzas P. Does anticoagulation improve outcomes of microvascular free flap reconstruction following head and neck surgery: a systematic review and meta-analysis. Br J Oral Maxillofac Surg. 2022;60(10):1292-1302. PMID 36328862

  5. 5. In a randomised trial in head and neck microsurgery, low-molecular-weight dextran improved flap survival compared with aspirin, with a similar rate of systemic complications.

    False

    In Disa's randomised trial the method of prophylaxis had no effect on overall flap survival, while systemic complications (heart failure, myocardial infarction, pulmonary oedema, pleural effusion and pneumonia) occurred in 51% with dextran for 120 hours, 29% with dextran for 48 hours and 7% with aspirin. Biermann's systematic review advises against dextran because of severe systemic complications.

    • Disa JJ, Polvora VP, Pusic AL, Singh B, Cordeiro PG. Dextran-related complications in head and neck microsurgery: do the benefits outweigh the risks? A prospective randomized analysis. Plast Reconstr Surg. 2003;112(6):1534-9. PMID 14578781
    • Biermann N, Chak JC, Wiesmeier A, Klein SM, Ruewe M, Spoerl S, et al.. Evidence-Based Approaches to Anticoagulation in Reconstructive Microsurgery-A Systematic Literature Review. Life (Basel). 2024;14(1). PMID 38255697