Abdominal aorta-iliac bypass and abdominal aorta-femoral bypass

Abdominal aorta and radial artery stenosis are not as common in China as in Western countries, and they are still one of the common diseases in vascular surgery. The majority of this disease is caused by atherosclerosis, and the range of involvement is regular. It is most common in the lower aortic segment of the abdominal aorta, involving the bilateral common iliac artery and the internal iliac artery. The external iliac artery is less affected or only The initial segment is involved within 1 to 2 cm. However, the disease is often progressive, can cause occlusion near the abdominal aortic bifurcation, but also can spread distally to the external iliac artery, the common femoral artery and the superficial femoral artery or even the iliac artery, leaving only the deep femoral artery as the lower limb. Supply blood vessels. Fortunately, the upper end of the inferior segment of the abdominal aorta, that is, near the renal artery, is rarely involved, so that reconstruction surgery can be completed in an easily revealed range. Abdominal aortic angiography is the most reliable qualitative and localized diagnostic method. There are two main surgical methods: endarterectomy and vascular bridging. Both procedures have advantages and disadvantages. Endometrial ablation can be accomplished by extraperitoneal route, relatively safe, with fewer complications, no foreign bodies, and less susceptible to infection, but only for those with relatively limited lesions, and the operation time is longer, and the large free blood vessels lose more blood. Big. Vascular bridging requires abdominal or extraperitoneal application, the vascular free range is small, the operation is relatively simple, the operation time is short, and it is not restricted by the scope of the lesion, but there are foreign bodies left, and infection may occur. Because the disease has a tendency to progress, sometimes the endometrial exfoliation can not prevent the spread of the lesion to the distal end, affecting the long-term effect, so in recent years, more bridging is used, and endometrial ablation is less. If the severe stenosis of the abdominal aorta is close to complete occlusion, but is ill or in an emergency, extra-anatomic bypass, such as the radial artery-femoral artery bridge and the femoral-femoral artery, is sometimes required. Bridge surgery. Treatment of diseases: abdominal aortic coarctation Indication Arterial stenosis or occlusion is a wide range, and endometrial exfoliation is difficult to achieve therapeutic purposes. Contraindications Due to poor general condition can not tolerate major surgery, or there is a peritoneal infection should not be a large abdominal surgery. Preoperative preparation 1. Prepare the skin from the xiphoid to the lower third of the thigh. Because of the possibility of changing the plan during surgery, the aortic-femoral artery bridging technique is changed. 2. Prophylactic use of antibiotics. Surgical procedure 1. Incision: Make a large median incision from the xiphoid to the pubic symphysis. If the abdominal aorta-femoral artery bridge is required, a bilateral thigh root incision is added. The incision is facing the femoral artery, the upper end is more than 1 cm beyond the inguinal ligament, and if necessary, it can be extended outward; the lower end should exceed the bifurcation of the femoral artery (Fig. 1.17.10.2.2-2). There is no need to cut the inguinal ligament and pull it upwards. 2. Expose the abdominal aorta: use a saline gauze pad to wrap the small intestine to the right side, cut the ligament of the flexor, and pull the duodenum to the upper right. The peritoneum was cut along the abdominal aorta on the left side of the mesenteric root. There are many lymphatic vessels in front of the abdominal aorta, which need to be cut off to prevent lymphatic leakage after surgery. Continue to dissociate up to the left renal vein, and if necessary, free it for a section and pull up to increase exposure. The lesion is in a high position and occasionally has to cut the left renal vein. Close to the inferior vena cava to cut off the left renal vein, generally does not cause severe reflux obstruction. The mesenteric vein is moved upward on the left side of the midline and is pulled to the left. The proximal aorta of the stenosis is relatively normal, and the blood vessel wall is soft. It can be used as an end-to-side anastomosis of the artificial vascular aorta. It is not necessary to make the aorta full circumference free. However, if the aorta still has a thickened intima that causes a narrowing of the lumen, it should be cut off and end-to-end anastomosis. To do this, one or two pairs of lumbar arteries should be cut off, and a 2 to 3 cm section of the aorta should be completely freed. 3. Exploring the radial artery: If the total or external iliac artery is intact, it can be bridged there, which has the advantages of less trauma, artificial blood vessels not extending and flexing, and less chance of wound infection. However, arterial occlusive disease continues to spread. Clinically, the long-term effect of femoral artery bridging is better than that of the radial artery. Therefore, it is currently advocated to perform abdominal aortic-femoral bridging. 4. Artificial blood vessel pre-coagulation treatment: Whether using woven or woven artificial blood vessels, pre-coagulation treatment is required to close the pores between the fibers without leaking blood, and form a smooth fibrin lining on the inner wall of the cavity, reducing The chance of thrombosis. At present, most of the woven polyester blood vessels are used, and the pre-coagulation should be sufficient. First, select the herringbone artificial blood vessel with the same or slightly smaller diameter as the abdominal aorta, and clip the ends of the two thin arms to the curved disc. 100 ml of blood is withdrawn from the abdominal aorta or inferior vena cava before systemic heparinization, inhaled into a needle-nosed sore device (sheet empty needle) or a syringe and docked with a artificial blood vessel placed in a vertical position, and the blood is slowly infused to fullness. At this point the vessel wall is gradually wetted and oozing out of the blood. Continue to inject blood (the blood leaking out to the curved plate can be reused) until the blood leakage stops. The blood used for perfusion will solidify within 2 to 3 minutes. If the artificial blood vessel is still not ready, new blood can be drawn. After the blood leakage stops, the vascular clamps that clamp the two thin arms are removed, the blood is released and repeatedly washed with heparin saline to remove the clots in the lumen and set aside. 5. Establish a tunnel: If you want to bridge to the femoral artery, start the tunnel while pre-coagulation of the artificial blood vessel. The ureter across the radial artery is first separated from the posterior, and the operator's fingers are closely attached to the anterior wall of the iliac artery and the anterior wall of the external iliac artery. The other finger is separated from the anterior wall of the femoral artery from the base of the thigh until the two fingers meet. Use a large bending pliers to pass through the tunnel from bottom to top, and lead a tape or a fine latex tube through the tunnel for use. 6. Heparinization Heparin was injected intravenously at a dose of 100 U/kg. Check the presence or absence of clots or fibrin fragments in the lumen of the artificial vessel. If available, remove it with forceps and flush with heparin. The excess artificial blood vessel thick arm portion is cut off according to actual needs. 7. Proximal end-to-end anastomosis for the end-to-side anastomosis. The upper and lower ends of the anastomosis should be controlled with a forceps. The lower end of the forceps should be inclined to block the lumbar artery at the same time. Large Satinsky forceps can also be used, but when the anastomosis is slightly small, it is better to divide the two clamps. The anterior wall of the abdominal aorta was cut between the two clamps to form an elliptical hole. Cut the thick end of the artificial blood vessel into a bevel and make an anastomosis with a 3-0 or 4-0 double needle single-strand non-absorbent line. The suture starts from the root of the slope, that is, the distal end, and the first stitch (or the first needle is used for valgus) is knotted. Then continue suturing from one side until the tip of the bevel is the centripetal end. Then use the same method to sew the other side, and tie the two lines to the tip. Note that when suturing the abdominal aorta, the needle should be inserted from the endometrium and the needle should be removed from the adventitia. Otherwise, there is a possibility of intimal stripping. More commonly used end-to-end anastomosis, the advantage is that the active membrane near the thickened inner membrane can be properly exfoliated to improve the quality of the anastomosis. After the transverse aorta was dissociated, the distal end was closed with a 3-0 single-strand non-absorption line, and two rows of sutures were made, one row of horizontal sputum, and one row of ordinary continuous sutures. Or it can be knotted by a line of continuous stitching. The proximal end is anastomosed to the artificial blood vessel, starting from the middle of the posterior wall, continuously valgus suture, and the two lines reach the anterior wall and then knot each other. 8. Check the anastomosis of the anastomosis: the open aortic occlusion forceps are immediately re-clamped, and the artificial blood vessel is filled with blood. The artificial blood vessel is clamped near the anastomosis, and the vascular clamp on the two thin arms (ie, the distal end) is removed, allowing the blood to be completely emptied. Open the abdominal aortic occlusion forceps again. If the blood leakage is serious, it can be re-blocked, and intermittent suture repair in the blood leakage; if the blood leakage is not serious, the blocking forceps can be taken out, and the anastomosis can be stopped by pressing the gauze for a while. 9. Cutting the distal part of the artificial blood vessel: According to the bridge to the radial artery or the femoral artery, the two thin arms of the artificial blood vessel are respectively shortened to the required length. After the pressure of the arterial blood flow through the polyester blood vessels, the annular wrinkles on the blood vessels will partially flatten and the blood vessels become longer, especially in domestic artificial blood vessels. During the cutting, the blood vessel must be stretched and measured and cut to avoid undue distortion after blood transfusion. For example, if the femoral artery bridge is used, the tape or fine rubber tube that has been indwelled firstly extends into the large bending forceps from the bottom to the top, and the tip of the artificial blood vessel is clamped to the triangular portion of the femur, taking care to avoid the rotation distortion, and then cutting. The artificial blood vessel should be cut into an S-shaped bevel with the root facing up and the tip facing down. 10. Distal anastomosis: Select the anastomotic site, and the vessel wall is less affected. The femoral artery bridging should be done as far as possible to make the bifurcation of the femoral artery so that the deep femoral artery opening can be clearly seen from the incision. If necessary, the endometrial exfoliation can be added, or the incision can be extended to the deep femoral artery opening to ensure that there is Sufficient blood flow. The anastomosis method is the same as the proximal end-to-side anastomosis. Only the bevel faces in the opposite direction, ie the bevel tip should be towards the telecentric end, with a 5-0 suture. Before the last needle of the anastomosis is knotted, the other end of the artificial blood vessel is clamped by the vascular clamp against the bifurcation, and the blocking forceps under the proximal anastomosis is intermittently released, and the blood flow is spewed from the gap of the anastomosis. The existing blood clot rushes out. For the same purpose, the distal blocking forceps are briefly released. After confirming that there is no clot, the suture is knotted to complete the anastomosis, and the above-mentioned blocking forceps are removed to restore the limb blood flow. The same method completes the distal end of the contralateral anastomosis. 11. Treatment of the inferior mesenteric artery: In order to expose and dissect the abdominal aorta, it is generally necessary to sever the inferior mesenteric artery (IMA), usually without causing ischemia in the left colon. However, if the preoperative angiography reveals that the IMA is grossly distorted and the superior mesenteric artery has insufficient blood supply, it may be necessary to replant the severed IMA. In the surgical exploration, IMA can be tried to block the blood flow of the left colon, and the intraoperative Doppler test is very helpful. If it is preliminarily judged that it needs to be re-implanted, the aortic wall of the IMA root should be pulled out to form a trumpet shape with the IMA. The gap in the aorta is sutured. At this point, try to open the IMA blocker. If there is enough blood to return, the IMA does not need to be replanted and can be ligated. Otherwise, it is implanted on the artificial blood vessel after the bridge is completed. Fortunately, this situation is rare. 12. After complete hemostasis, close the posterior peritoneum and cover the artificial blood vessels. The incision was sutured layer by layer. Do not let the drainage. complication 1. Anastomotic bleeding or bleeding on the wound surface. 2. Incision infection, infection with thigh root incision is more common. 3. Thrombosis in the arterial bridge can spread to the distal end. 4. Exfoliated blood clots or endometrial plaques can cause distal arterial embolization of the lower extremities. 5. Erectile dysfunction. Do not widely dissipate the bifurcation of the abdominal aorta (especially to the left) to reduce the chance of damaging the nerve plexus. It has been suggested that a lateral-lateral anastomosis to the common iliac artery can be added midway through the abdominal aorta-femoral artery to improve the blood supply to the inferior epigastric artery, which is helpful for the prevention and treatment of vasculogenic impotence.