Experimental Study for Microvascular Anastomosis

Recent progress in microvascular surgery has opened new clinical possibilities in tissue transplantation, replantation by the direct anastomosis of vessels about onemm in external diameter. However in spite of continous training, the use of improved microscopes, instrument and suture material, it is still dificult to obtain high patency rate. Increasing facility obtained only by repeated operation upon the experimental animal reduce the false rate of arterial anastomosis and should make availability on additional and mastery technic in repeated experimental exercise for operation preocedure requiring the anastomosis of small artery. The purpose of this paper is to describe the instrument being used and to point out their use in end to end end anastomosis of femoral artery of rat, and to emphasize the role and important factors in the surgical repair of small artery with suture techniquq. Preliminary experimental study for microvascular anastomosis was projected to three step. The femoral artery of living rat was used in last step about 30 case, and then obtained patency rate 19 case and false 11 case. The result to the analysis for false 11 case are as follows. 1. Two case by insufficient dissection of femoral artery of rat. satisfactory dissection is from its emergence at the inguinal ligament to its bifurcation, and the greater mobilization, the easier femoral artery of rat is to approximate, turnover, and revise, if necessary. Dissection of tissue must be slow to avoid vessel damage. 2. One case by extreme vascular spasm. Due to manipulation, especially cold, dry, contact with fresh blood, vessel is usually spasm. Vascular spasm can be reversed by topical applcation of 1% lidocain and by keeping constant moisture with warm 37℃ Ringer solution. Vessel trauma by rough handling is not responded by lidocain or irrigation. 3. Three case by unskilled handling of clamp-approximation. Questionable problem is on which side the clamp should be placed? Which clamp should be placed on proximal or distal? How far apart the clamp should be placed and where they should be applied? Which should be closed first, the proximal clamp or the distal one? Above description was solved. 4. Threee case by unskilled microvascular suturing. Questionable problem is where the guide suture should be placed? How large a bite should be taken? How many suture will be required? Above description was solved. 5. Two case by thrombosis after vascular anastomosis. Thrombosis has been a major problem. Surgical trauma of vessel and unskilled technique of anastomosis were lead to thrombosis formation in microvascular surgery. Patency rate after microvascular surgery depends mainly upon good visualization of vascular anatomy and good technique including tissue dissection and microvascular suturing, gentle manipulation of vessel, fine and appropriate instrument.