Renal endarterectomy

Treatment of diseases: renal artery embolization, renal artery atherectomy Indication Renal endarterectomy is available for: Secondary renal artery stenosis caused by atherosclerotic plaque is the most common cause of renal vascular hypertension in foreign countries. Renal artery intima removal is often used to relieve obstruction. The plaque extends from the abdominal aorta and can block one side of the renal artery. It can also cause bilateral obstruction. All of them need to be cut through the abdominal aorta-renal artery to remove the plaque adhering to the intima, first by Dos Santos. In 1949, it was promoted. As long as the renal artery in the distal segment of the obstruction remains normal, and there is no extensive secondary thrombosis in the branches of the parenchyma, this method can be performed, which is more suitable for elderly and frail patients. Preoperative preparation 2 weeks before surgery should be given to the general antihypertensive drugs, in order to avoid a sudden drop in blood pressure after surgery, resulting in extremely severe blood perfusion of vital organs and crisis. If the blood pressure is particularly high, and the diastolic blood pressure is as high as 16 to 18.7 kPa (120 to 140 mmHg), a short-acting antihypertensive agent such as -methyldopa (alphamethyldopa) can still be applied, which can appropriately delay the timing of surgery. The experience can last until the preoperative. If surgery is urgently needed and hypertension cannot be controlled, intravenous sodium nitroprusside can be used to meet the conditions required for surgery. The blood volume of such patients is reduced by 500-1500 ml compared with normal, and should be supplemented before surgery to avoid shock caused by postoperative blood pressure drop. Hypokalemia due to secondary aldosteronism and long-term diuretic therapy should be corrected before surgery to reduce the sensitivity of anesthesia and surgery to myocardial irritation. Any infection of the urinary system should be controlled and cleared before surgery. Pyelonephritis is given effective anti-infective treatment 3 weeks before surgery. If azotemia is present, it should be properly corrected. For the stenosis caused by aortitis, comprehensive treatment is needed. After the active period, the local lesions are stable, and surgery can be performed. In order to protect the renal parenchyma that has been damaged by ischemia, it is in the best functional state. In addition to avoiding the use of nephrotoxic drugs, mannitol or furosemide can be administered shortly before surgery. Systemic heparin therapy should also be initiated before surgery to prevent postoperative thrombosis. The above two treatments also need to be repeated before clamping the renal artery and need to be maintained until the end of the operation. Intraoperative central venous pressure monitoring should be done before the catheter and device. The fluids and related instruments required for cold perfusion of the renal arteries that may be performed during surgery should be prepared. Surgical procedure Unilateral renal artery endarterectomy The traditional method is performed from the aortic incision. Around the opening of the renal artery, the abdominal aorta is closed by partial clamping, the main artery is cut open, and extended to the abdominal aorta as needed, and then the endometrium and the hardened plaque are exfoliated from the gap in the middle layer of the artery wall until the main A plaque attached to the artery. After the endometrium is removed, the embolus and residual plaque debris in the distal renal artery are washed with heparin physiological saline. Because the renal artery wall after endometrial ablation is fragile and thin, the incision can be repaired with an autologous venous valve or with Dacron, Gortex instead of a woven piece, which is beneficial for preventing re-stenosis. 2. Bilateral renal artery endarterectomy Abdominal aortic incision renal artery endarterectomy, one-stage surgery can also treat bilateral lesions, even the narrowing of the abnormal arterial opening of the kidney. The abdominal aorta is completely free from the upper mesenteric artery to the bifurcation of the radial artery. The lumbar artery branch should be ligated and cut for easy separation. The abdominal aorta is clamped at the plane of the superior and inferior mesenteric arteries, and the mesenteric artery and renal artery are clamped to prevent blood return. Heparin 3000-5000U was intravenously injected 30 minutes before the clamp. The aorta is longitudinally incised, and the exfoliation of the intima and sclerosing plaque can begin at the incision of the anterior wall of the aortic artery, break away from the distal end, and be stripped from the posterior wall, and sutured with a needle. The inner membrane is fixed with 6~8 needles in the middle and outer membrane sutures to avoid peeling damage. The inner membrane and the plaque are pulled upward to continue to peel off to the opening of the renal artery, and the inner membrane and the plaque are pulled outward, and are pulled out from the normal end membrane. If the contralateral renal artery also has a plaque blockage, it should be removed by the same method. The intima was cut from the upper incision and the plaque was completely removed. The arterial cavity is flushed with heparin salt solution, and the renal artery clamp is opened to flush out the residue in the cavity. The aortic anterior wall incision was continuously sutured with a nylon thread or a silk thread. If there is still bleeding after opening the forceps, it is strengthened by suture stitching. Those who have difficulty are patched with Dacron tablets. For example, the hardened plaque of the abdominal aorta is only the opening of the renal artery, and the abdominal aorta can be cut transversely. The abdominal aorta is clamped on the upper and lower sides of the renal artery to control the return of blood to the renal artery. The anterior wall of the abdominal aorta is first transected, and then the renal artery is extended and cut to the plaque. Then, the intima and plaque are exfoliated from the middle layer, and the intima of the posterior wall of the aorta is separated, and the opening of the renal artery and the proximal endometrium are removed together. Clean the arterial lumen. The distal edge of the distal and proximal endometrium is sutured with a suture stitch and a middle needle and an outer membrane. When there is no residue after washing, the artery wall incision is continuously sutured or repaired with a graft.