**4.3 Tips and pearls**


**213**

**5. Couple devices**

**Figure 6.**

*Basic Principles in Microvascular Anastomosis and Free Tissue Transfer*

• At the end of an anastomosis, we must check its permeability, for example by means of a patency test. Other possibility is to make a profuse irrigation through the space left in the microvascular anastomosis before placing the last two stitches, an inflation and slight dilatation of the anastomosis with the heparinised serum evinces the vascular patency (**Figure 6**). The classic patency

*anastomosis is completed full of heparinised serum, until clamps are released.*

*Patency test with rinsing. A short Abbocath cannula is introduced in the microvascular anastomosis in between the space left by the two late stitches, we pretend to verify an easy dilatation before finishing the suture. The* 

• The learning of these techniques must begin in a laboratory of experimental

• Dilatation of the lumen with specific dilator forceps allows better visualisation of the interior of the vessel, easily recovering the needle at each stitch.

• Before passing the entire thread through the anastomosis, the former should be in line with the vessels, and not angulated behind the needle. This precaution will avoid tears and friction on the vessel wall with the thread passage.

Since the onset of microsurgery, a great interest was drawn towards the development of suture techniques to perform anastomoses more quickly and automatically, in order to buffer inaccuracies [28]. For this purpose, devices in the form of two

Currently, its use is widespread, mainly for vein anastomoses, although they have also tested a 100% patency in arterial ones. The vessel is introduced through the ring and the edges are fixed inside-out in the pins arranged in the ring, then the same is done with the other vessel and the hinge of the device, that joins both sides, is closed. The eversion of the edges achieves less exposure of the vascular lumen to foreign

• Limit the vessel dissection as much as possible (**Figures 1** and **2**).

metal rings that are coupled, known as coupler devices, were developed.

*DOI: http://dx.doi.org/10.5772/intechopen.91917*

test can traumatise the intima.

surgery with animal models [29].

*Basic Principles in Microvascular Anastomosis and Free Tissue Transfer DOI: http://dx.doi.org/10.5772/intechopen.91917*

#### **Figure 6.**

*Vascular Biology - Selection of Mechanisms and Clinical Applications*

anastomosis is frequently chosen.

suture technique [28].

lumen can be useful.

entire anastomosis.

**4.3 Tips and pearls**

**Figure 5.**

Therefore, it is very useful in lower limb reconstructions, when one of the vascular axes is damaged or we want to preserve the integrity of all [27]. For example, in head and neck surgery, after a cervical dissection, the high rate of venous thrombosis makes it advisable to choose the internal jugular as recipient vein [6]. In view of the discrepancy between the internal jugular and the vein of any flap, as well as the pertinence of maintaining the flow through the internal jugular, an end-to-side

*One-way-up technique. First four to five stitches are placed in the posterior wall in an inverted fashion. It is important to leave only a small gap between the two first knots in this posterior wall, in order to avoid leakages and reviews here. After these first inverted stitches, the rest of them are placed in a conventional simple fashion* 

*as depicted in the figure. This technique avoids twisting and injuring the anastomosis.*

To perform this end-to-side anastomosis, we must occlude the flow through the larger vessel that will remain in continuity. Our preference is the use of two rubber loops with a double pass around the vessel. When tensioning these loops, it seems that the damage to the walls of the vessel is inferior than with bulldog or baby Satinsky clamps. Next, by putting traction on the wall of the vessel with a transmural suture, we elongate the wall and make a section with the straight adventitectomy scissors or with a scalpel [27]. The diameter of the hole created must not be greater than the one on the vessel present in the free flap. If possible, the flap is tilted over the anastomosis to suture the posterior face; otherwise, we will use a one-way-up

• It is important to take within each suture a good amount of intima to adequately evert it and expose smooth intima to the vascular lumen, with scarce

• The knots should be flat, placed on one side, with the right pressure just to close the anastomosis, since very tight sutures can cause isquemia and failure.

• In case of working with veins of inconsistent walls, to perform an immersion technique, using abundant heparinised serum in the field to open the vascular

• We should not allow leaks in the anastomosis; these will cease through the formation of an intraluminal thrombus, which can ultimately endanger the

subendothelial collagen or suture material.

**212**

*Patency test with rinsing. A short Abbocath cannula is introduced in the microvascular anastomosis in between the space left by the two late stitches, we pretend to verify an easy dilatation before finishing the suture. The anastomosis is completed full of heparinised serum, until clamps are released.*

