After obtaining exposure and control of the artery, the next stage in all procedures is opening the vessel. The length of the arteriotomy and whether it is performed transversely or longitudinally depends principally on which procedure is being carried out. If an embolectomy is being performed, a transverse arteriotomy usually suffices and can be closed primarily. However, if it is anticipated that an endarterectomy or graft anastomosis will be necessary, a longitudinal arteriotomy is used. Except where the artery is very large, it is not possible to close such an arteriotomy primarily and a patch will be required. The danger with primary closure of a longitudinal arteriotomy is the creation of a significant stenosis with all the expected haemodynamic consequences.
Technique
Most surgeons use either a number 11 or 15 blade. The vessel should be steadied (but not grasped) so that it is stabilised whilst the arteriotomy is being fashioned. Make the incision in the centre of the surface of the artery facing you.
With the blade pointing away from you, a short stabbing technique should be used. Sudden movements and excess pressure can lead to the posterior wall of the vessel being either traumatised or incised. In the real-life situation, remember that the opposite wall of the artery may be diseased and, therefore, more vulnerable to this kind of inadvertent injury.
On entering the lumen proper a 'flash' of blood will be seen. At this point use Potts' angled scissors to complete the arteriotomy. The lower blade of the scissors should be placed in the lumen of the artery with care. By lifting this blade towards you, damage to the opposite side of the vessel will be avoided. Then, cut the desired length of arteriotomy with even cuts (Figure 1.1).
For a transverse arteriotomy, open between one-third and a half of the circumference of the vessel. At this stage, all blood should be aspirated away with a sucker and then the luminal surface can be inspected by using closed forceps to distract the walls of the vessel.
Figure 1.1
Arteriotomy being performed with Pott's angled scissors
Transverse arteriotomy: primary closure
Begin this exercise by using a double-ended polypropylene suture (you will be provided with 5/0) starting in the corner of the arteriotomy. Both needles should be inserted from inside the vessel lumen to outside and then a knot tied.
Next, a continuous suture is placed to close the vessel. So that distal intimal flaps are secured and arterial dissection avoided, it is important to complete the vessel closure by placing the needle from outside to in on the 'upstream side' of the arteriotomy and from inside to out on the 'downstream' side.
The suture line should be comprised of evenly spaced bites of adequate depth in the vessel wall to achieve a haemostatic anastomosis. If the bites are uneven or too deep, leak points will develop. Equally, if the bites are too superficial the suture will cut out.
In the real-life situation, temporary release of the clamps is necessary followed by generous lavage with heparinised saline, to flush out any thrombus or atheromatous debris.
Finally, tie the suture with at least six throws in your knot. If extra sutures are required at leak points, they should be inserted after clamps have been re-applied and attempts to place sutures without clamps resisted.
