Limb Ischemia and Reperfusion During Abdominal Aortic Aneurysm Surgery

Purpose Abdominal aortic aneurysm (AAA) surgery involves ischemia and reperfusion of the lower extremities, but assessing the pathophysiological changes is difficult. We evaluated the extent and time course of ischemia–reperfusion injury of the lower extremities during AAA surgery.Methods To monitor oxygen metabolism, two near-infrared spectroscopy (NIRS) probes were positioned on each calf muscle of nine patients undergoing AAA surgery. Lactate and pH were also measured in both iliac veins.Results Near-infrared spectroscopy signals responded sensitively to aortic cross-clamping and declamping. Lactate increased gradually and exponentially during aortic cross-clamping, and reconstruction of the first iliac artery resulted in a further but transient increase in ipsilateral venous lactate. The time course of the pH level after declamping was almost a mirror image of that of lactate. Reconstruction of the first iliac artery did not affect the contralateral NIRS signals, lactate, or pH.Conclusions Near-infrared spectroscopy may be useful for monitoring limb ischemia during AAA surgery. The transient increase in lactate and the transient decrease in pH after first declamping may contribute to the mechanism of declamping shock. The fact that first declamping did not affect measurements on the other side shows that contralateral ischemia progresses steadily after reconstruction of the first iliac artery. Therefore, reconstruction of the second iliac artery should be done as soon as possible.     

盐酸沙格雷酯在腹主动脉瘤腔内修复术后防治臀肌和下肢缺血的初步观察

目的观察盐酸沙格雷酯在腹主动脉瘤腔内修复术后防治臀肌和下肢缺血的作用。方法回顾性收集我院血管外科2006年1月至2011年1月期间收治的腹主动脉瘤行腔内修复术(EVAR)治疗的患者174例,年龄(71.8±8.2)岁,其中男148例,女26例。腹主动脉瘤直径(55.2±12.9)mm,累及髂总动脉52例(29.9%)。EVAR治疗方法包括置入分叉型人工血管支架169例(97.1%),单臂型5例(2.9%)。其中术中封闭单侧髂内动脉29例,封闭双侧髂内动脉10例,术后均口服盐酸沙格雷酯100 mg,3次/d,阿司匹林100 mg,1次/d 2～4周。随访观察术后患者臀肌和下肢发生缺血情况。结果全部病例行EVAR术顺利,无中转开腹;行全身麻醉88例(50.6%),硬膜外阻滞麻醉52例(29.9%),局部麻醉34例(19.5%);术中失血量为(125.2±43.1)ml,术中无输血,手术时间为(145.5±38.7)min;术后ICU观察时间和禁食时间分别为(14.7±5.2)h和(7.2±4.3)h;术后平均住院时间为(9.1±2.7)d。围手术期并发症发生率为12.6%(22/174),术后30 d死亡率为1.1%(2/174)。术中封闭单侧髂内动脉29例中2例出现同侧臀肌轻度疼痛,行走疼痛加重,跛行距离100 m,5例出现同侧下肢乏力,间歇性跛行距离100～200 m;封闭双侧髂内动脉10例中4例术后出现臀肌轻度疼痛,跛行距离200 m,均采用口服盐酸沙格雷酯和阿司匹林扩血管、祛聚治疗后2～4周好转,间歇性跛行距离均大于500 m,无臀肌坏死发生,无再行介入或外科干预治疗,中位随访时间16.1个月,未诉特殊不适。结论盐酸沙格雷酯在EVAR术后防治臀肌和下肢缺血疗效满意,尤其适合于封闭双侧或一侧髂内动脉和合并下肢动脉硬化闭塞者。     

Percutaneous Endovascular Treatment for Chronic Limb Ischemia

Percutaneous transluminal methods of revascularization for chronic limb ischemia have traditionally been used as an adjunctive or secondary mode of treatment. This study examines the outcomes of patients treated via endovascular methods as the primary form of treatment. The records of 66 patients (average age, 71.3 years; range, 53 to 92) with chronic limb ischemia treated from November 2000 to January 2002 at a single institution with endovascular methods were retrospectively reviewed. Thirty-one patients had disabling claudication, 15 had rest pain, 17 had minor tissue loss, and 3 had major tissue loss. There were 94 lesions in the 66 limbs: 45 lesions in the superficial femoral artery, 28 lesions in the popliteal artery, and 21 lesions in tibial arteries. Occlusive lesions were treated by subintimal angioplasty. Stenoses were treated by percutaneous transluminal angioplasty (PTA). The median length of the lesions was 12 cm. Forty-six stents were placed in 32 patients; 34 patients did not receive stents. The approach was contralateral in 71% (47/66) and ipsilateral in 29% (19/66) of cases. Patients were followed up with physical exam, anklebrachial index (ABI), and duplex ultrasonography. Postintervention medical treatment included aspirin and clopidogrel. Long-term patency was correlated with age, comorbidities, risk factors, and the use of stents in addition to angioplasty. Endovascular treatment was technically successful in 65 of 66 patients (98%). Residual stenosis (<30%) was found in three cases, two in patients with PTA alone and one patient with PTA and a stent. Mean length of follow-up was 6.3 months (range, 6 weeks to 15 months). Postintervention ABI improved from a mean of 0.65 to a mean of 1.01 (p < 30.05). The perioperative complication rate was 9% and included three cases of hematoma and one case each of thrombosis, lymphocele, and rash reaction to medications. Outcome measures included primary patency (89%), assisted primary patency (96%), and limb salvage (97%) at 6 months. Restenosis of >50% occurred in four patients and occlusion occurred in two. At 6 months, patients with one or more stents had a patency rate of 84% (27/32), whereas those without a stent had a patency rate of 94% (32/34) (p=NS). Endovascular treatment is a safe, feasible, and effective method with a high short-term patency rate and may be used as an alternative to bypass for chronic limb ischemia.Presented at the Twenty-ninth Annual Meeting of the Peripheral Vascular Surgery Society, Anaheim, CA, June 4-5, 2004.     

New Technique for Retrograde Cerebral Perfusion During Arch Aneurysm Repair

Many techniques are used to reduce brain damage during surgery for dissecting aneurysms of the ascending aorta and arch. Recently, new techniques of protection were proposed, consistent with hypothermic circulatory arrest in association with retrograde cerebral perfusion via superior vena cava. We propose a simple, time-saving method, which does not require any manipulation of the heart. We use a multilumen cannula for cardioplegia (D 860-DIDECO FUNDARO') with pressure transducer. This cannula is inserted in superior vena cava by means of a simple purse-string, and linked to the arterial line with a “Y” derivation, allowing retrograde perfusion of the brain and monitoring the perfusion pressure at every moment. The superior vena cava placed downstream from the cannula is closed by a small vascular clamp, to avoid blood reflux in the right atrium. This method is timeand money-saving, is readily available, and can be prepared whenever necessary, also in the middle of the surgical procedure.     

腔内修复术治疗胸主动脉夹层的手术配合

对50例DeBakeyⅢ型胸主动脉夹层患者采用腔内修复治疗.结果 手术过程顺利,手术时间100～180 min.术后24 h可下床活动,未发生并发症.术后行CT动脉造影复查发现支架位置稳定,假腔无活动性血流.提出术前了解患者特点及手术步骤,对术中可能发生的突发事情有精神准备和技术准备,术中器械护士掌握各种器械的性能,退回护士做好心理护理及病情观察,以保证手术的顺利进行.