Using Incidental Side Branches of Vessels for Intraoperative Cannulation and Irrigation of the Microvascular Anastomosis

One of the most critical problems in microsurgery is the microvascular thrombosis of both the performed anastomotic and postanastomotic vessels.[1] [2] However, the basic management of this problem includes the refreshment of the anastomosis after the removal of the old one; sometimes taking one or two sutures off and irrigation of the anastomotic and the perianastomotic luminal distance with antithrombotic agents via 22 to 26 G angiocatheters may prevent formation of a new clot. Previous reports by Chen et al showed significant reduces in thrombosis rate at the anastomosis site especially in crushed vessels by the topical irrigation with heparin or enoxaparin solution, at the concentration routinely used clinically.[3] [4] Thus, authors routinely use such irrigation method by using possible side branches after refreshment of anastomosis without the removal of sutures from the anastomosis or entering via the anastomotic area.

When we find suitable side branches during both free flap pedicle and recipient vessel's dissection, these side branches are reserved and marked with bulldog clamps for cannulation and irrigation ([Fig. 1]). These incidental side branches should be close to the anastomosis area with suitable calibre for cannulation ([Fig. 2]). This gives the surgeon the opportunity to remove any clots in the anastomotic area and irrigate the vessel without taking the sutures off. Also, it is available to irrigate postanastomotic vessels in circumstances of the suspicion of microthrombi including the vessels inside the flap.[5] Another advantage of using side branches is that they allow standard angiocatheters to pass from proximal end to the distal end of the vessels to act as a stent which helps anastomosis especially if there is a calibre discrepancy. Using stents or intravascular thermosensitive gels without any microclamps were reported to be useful in microvascular anastomosis without any trauma on vessel edges.[6]

Fig. 1 Schematic view of cannulation and irrigation procedure via the side branch of anastomosed vessels. Note that the irrigation of the opposite direction of the main artery by using the branch as a joystick is also possible (dotted lines).

Fig. 2 Intraoperative view of cannulation and irrigation of anastomosis (*) and the vessel by using a 24-G angiocatheter. The case was a total lower lip reconstruction with gracilis muscle free flap.

The main restriction of the method is the possibility of isolating a side branch with suitable distance to the anastomosis for the irrigation with routinely used angiocatheters. If there is a branch which is not too close to anastomotic area, we use 22- to 26-G–sized pediatric central venous catheters (Ayra Medical, Ankara, Turkey) with sufficient length to pass through the anastomosis. However, if all these procedures fail, the salvage is usually based on excision of the clotted anastomotic distance and reanastomosis. But other antithrombotic treatments such as thrombectomy, heparinization, and antithrombic agents also should be performed in an algorithmic fashion as Khansa et al reported in their large series of microsurgical breast reconstruction.[1] Also, there are successful attempts to rescue the flaps by using subcutaneous tissue plasminogen activator in head and neck reconstruction.[7]

We are also working on the side branches for continued irrigation with saline and antithrombotic agents in anastomoses which tend to obstruct and on a novel endovascular monitorization method for microvascular anastomosis. This seems useful especially in severely destructed finger replantations in which vein grafts were used with their side branches to perform continuous irrigation if needed. The results will be reported soon.

In our opinion, preserving the rare side branches of the vessels may be useful for the irrigation of microvascular anastomosis and perianastomotic luminal distance.

• References

• 1 Khansa I, Chao AH, Taghizadeh M, Nagel T, Wang D, Tiwari P. A systematic approach to emergent breast free flap takeback: Clinical outcomes, algorithm, and review of the literature. Microsurgery 2013; 33 (7) 505-515
• 2 Egozi D, Fodor L, Ullmann Y. Salvage of compromised free flaps in trauma cases with combined modalities. Microsurgery 2011; 31 (2) 109-115
• 3 Chen LE, Seaber AV, Urbaniak JR. Thrombosis and thrombolysis in crushed arteries with or without anastomosis: a new microvascular thrombosis model. J Reconstr Microsurg 1996; 12 (1) 31-38
• 4 Chen LE, Seaber AV, Korompilias AV, Urbaniak JR. Effects of enoxaparin, standard heparin, and streptokinase on the patency of anastomoses in severely crushed arteries. Microsurgery 1995; 16 (10) 661-665
• 5 Lee DS, Jung SI, Kim DW, Dhong ES. Anterograde intra-arterial urokinase injection for salvaging fibular free flap. Arch Plast Surg 2013; 40 (3) 251-255
• 6 Giessler GA, Fischborn GT, Schmidt AB. Clampless anastomosis with an intraluminal thermosensitive gel: first application in reconstructive microsurgery and literature review. J Plast Reconstr Aesthet Surg 2012; 65 (1) 100-105
• 7 Froemel D, Fitzsimons SJ, Frank J, Sauerbier M, Meurer A, Barker JH. A review of thrombosis and antithrombotic therapy in microvascular surgery. Eur Surg Res 2013; 50 (1) 32-43