Ipsilateral foot drop after aortobifemoral bypass

Peripheral nerves can be injured by a direct result of the anesthetic technique of regional anesthesia or it can be contributed/compounded by poor perioperative positioning and padding, tourniquets, and the nature of surgery and diseases affecting the microvasculature of nerves. We present a case of perioperative peripheral nerve injuries which could not be explained by anesthesia technique nor surgery per se.

Dexmedetomidine for prevention of skeletal muscle ischaemia-reperfusion injury in patients with chronic limb ischaemia undergoing aortobifemoral bypass surgery: A prospective double-blind randomized controlled study

Background: Dexmedetomidine is a selective α-2 agonist used for sedation. It has also been shown to have myocardial protective effect and prevent ischemia-reperfusion injury in off-pump coronary artery bypass patients. The aim of our study was to assess the effect of dexmedetomidine for prevention of skeletal muscle ischemia-reperfusion injury in patients undergoing aortobifemoral bypass surgery. Methodology: Sixty adult patients (Group dexmedetomidine n = 30, Group normal saline n = 30) undergoing aortobifemoral bypass surgery were recruited over 3 months. Randomization was done using a computer-generated random table. The attending anesthesiologist would be blinded to whether the drug/normal saline was being administered. He would consider each unlabeled syringe as containing dexmedetomidine and calculate the volume to be infused via a syringe pump accordingly. Dexmedetomidine infusion (1 mcg/kg) over 15 minutes was given as a loading dose, followed by maintenance infusion of 0.5 mcg/kg/h till 2 h postprocedure in Group dexmedetomidine (D) while the same volume of normal saline was given in the control Group C till 2 h postprocedure. Creatine phosphokinase (CPK) values were noted at baseline (T0), 6 h (T1), 12 h (T2), and 24 h (T3) after the procedure. Hemodynamic variables (heart rate [HR] and mean blood pressure [MAP]) were recorded at T0, T1, T2, and T3. Results were analyzed using unpaired Student's t-test, P < 0.05 was considered statistically significant. Results: MAP and HR significantly decreased in Group D as compared to control group (P < 0.05). However, the decrease was never <20% of the baseline. The CPK values at 6, 12, and 24 h were statistically significant between the two groups. Conclusion: Dexmedetomidine prevents skeletal muscle ischemia-reperfusion injury in patients undergoing aortobifemoral bypass surgery.

Experiences of Surgical Treatment for Juxtarenal Aortic Occlusion

PURPOSE: To evaluate the outcomes of juxtarenal aortic occlusion (JRAO), a review of 15 patients who underwent aortic bypass replacement following aortorenal thrombectomy, especially focusing on the safety of suprarenal aortic clamping or transient aortic compression, was undertaken. MATERIALS AND METHODS: During the period of June 2001 to November 2012, 15 patients with JRAO (chronic 10, acute 5) were analyzed retrospectively. JRAO with combined stenosis of the renal artery was found in 2 patients, renal artery thrombus in 8 patients, and normal in 5 patients. RESULTS: All patients were males. Mean age was 61.7+/-11.2 years. There were 14 aortobifemoral bypass grafting and 1 aortobiiliac bypass grafting. Six Dacron and 9 PTFE artificial Y-grafts were implanted to the aorta with end-to-end anastomosis in the proximal aorta. Suprarenal aortic clamping was performed in 7 patients, supraceliac clamping in 2 patients, and transient aortic compression in 6 patients. There were 13 cases with aortic clamping time 10 minutes. Thrombectomy of the aorta and renal artery was performed in 10 (66.7%) patients. There were no operative mortality cases. The perioperative morbidity rate was 26.7% (4/15). Preoperative renal function was impaired in four patients. The renal functions of these cases were recovered postoperatively. CONCLUSION: Aortic bypass replacement following aortorenal thrombectomy with suprarenal aortic clamping or transient aortic compression for JRAO is the optimal treatment. It is important to focus on short renal ischemic time during suprarenal aortic clamping for prevention of renal damage. It provides unmatched perioperative and long-term results.

The accidental renal artery embolism in patient with aortoiliac occlusive disease with unilateral renal atrophy during aortobifemoral bypass graft: A case report

Aortoiliac occlusive disease occurs commonly in patients with peripheral arterial disease. Aortofemoral bypass is the most common surgical procedure to treat aortoiliac occlusive disease. Intraoperative renal artery embolism is rare complication that may occur during aortofemoral bypass in patients with aortoiliac occlusive disease. It is very important to prevent the risk of subsequent renal artery thrombotic or atheromatous embolism during aortofemoral bypass in patients with juxtarenal aortic occlusion because of accidentally dislodging fragments or atheromatous emboli into the renal arteries. Emboli to one or more major renal arteries are an occasional cause of renal failure. We report a case of renal artery embolism in patient with aortoiliac occlusive disease and unilateral renal atrophy during aortobifemoral bypass graft.

Uso do azul de metileno na reversão de vasoplegia refratária ao uso de catecolaminas após bypass aortobifemoral / Use of methylene blue in the reversal of vasoplegia refractory to the use of catecholamines after aortobifemoral bypass

Há evidências de que o óxido nítrico (NO) tem importância na vasodilatação associada a reações vasoplégicas. O objetivo deste relato de caso é documentar um caso de vasoplegia refratária ao uso de catecolaminas após bypass aortobifemoral revertida com o uso de azul de metileno. Mulher, 50 anos, submetida a bypass aortobifemoral. Sem comorbidades. Saiu de sala cirúrgica extubada, estável e com pulsos distais presentes. Duas horas após a cirurgia, evoluiu com choque circulatório. Iniciada noradrenalina e investigadas causas de choque. Manteve-se com necessidades crescentes de aminas e parâmetros estáveis. No sexto dia pós-operatório, com a hipótese de vasoplegia refratária, optou-se pelo uso do azul. Resposta imediata, com queda nos níveis de aminas, sendo desligada a noradrenalina no dia seguinte. O azul de metileno inibe a guanilato ciclase, produtora de guanosina monofosfato cíclico. Especula-se que haja um sinergismo entre essas drogas, já que a sua associação permite a atuação do sistema adenosina monofosfato.

There is evidence that the nitric oxide plays an important role in the vasodilation associated with vasoplegic reactions. The objective of this case report is to document a case of catecholamine-refractory shock after aortobifemoral bypass treated with methylene blue. A 50-year-old woman was admitted for aortobifemoral bypass graft surgery. She did not present with any comorbidities. At the end of the surgery, she was breathing spontaneously, with palpable pedal pulses. Two hours later, the patient presented shock. Noradrenaline infusion was initiated and the causes of shock were investigated. She required increasing doses of amines and her parameters were stable. On the sixth day after surgery, methylene blue was administered due to the hypothesis of refractory vasoplegia. There was immediate response, with decrease in the catecholamine infusion levels until its withdrawal on the next day. Methylene blue inhibits the enzyme guanylate cyclase that produces GMPc. There might be a synergism between these two drugs, since their association allows the action of the AMPc system.

Surgical Treatment for Aortoiliac Occlusions

PURPOSE: To evaluate the efficacy of surgical treatment for multilevel aortoiliac occlusive diseases, we retrospectively analyzed 89 recent cases surgical treatment was used. METHODS: From March 1992 to July 2001, we performed 62 aortobifemoral bypasses and 27 other bypasses as primary procedures. We analyzed surgical indications, combined diseases, cardiac risk assessment, type of occlusion, treatment modalities and cumulative patency rate. RESULTS: In 59 aortobifemoral bypasses, 8 end-to-end and 51 end-to-side proximal anastomoses were performed. Adjuvant PTA, with or without stent before bypass operation, was performed in 13 cases. Types of occlusions were Rutherford type I in 18.0%, type II in 20.2% and type III in 61.8%, respectively. Associated diseases were hypertension, diabetes, cerebrovascular accidents, and myocardial infarction in order of frequency. Mean follow-up duration was 36.4 months. Cumulative patency rate by life table analysis was 77.5%. Leg or foot amputations were performed in 13 cases (14.6%) after bypass operations. Two cases of amputation were performed after 13 simultaneous infrainguinal bypasses, and in 4 cases after staged infrainguinal bypasses. Operative mortality occured in 4 cases (4.5%). CONCLUSION: Aortobifemoral bypass remains one of the most durable and effective arterial reconstructions, for extensive aortoiliac occlusive diseases in young patients with low operative risk. Simultaneous infrainguinal bypass is preferred in patients with poor distal run-off.

Treatment of Aortoiliac Occlusions According to Multiple Competiting Therapeutic Options

The aortoiliac segment is one of the common site of chronic arterial occlusive disease which causes ischemic symptoms in the legs and feet. From March 1992 to December 1997, we performed 45 aortobifemoral bypasses, 14 femorofemoral bypasses, 3 iliofemoral bypasses, 1 ilioiliac bypass and 2 axillobifemoral bypasses. In 45 aortofemoral bypasses, 8 end-to-end proximal anastomosis and 37 side-to-end anastomosis were done. Adjuvant PTA with/without stent insertion before bypass operation were performed in 10 cases. Occlusive patterns of the disease were type I in 10.9%, type II in 23.5% and type III in 65.6% respectively. Associated diseases were hypertension, diabetes, cerebrovascular accidents, and myocardial infarction in order of frequency. In cardiac risk analysis according to the Eagle's criteria, high risk group was 4.7%, intermediate risk group was 53.1% and low risk group was 42.2% of total. Mean duration of follow-up was 12.1 months. Cumulative patency rate by life table analysis was 83.1%. Leg or foot amputations were done in 10 cases (15.6%) after operation and graft occlusion in 11 cases (17.2%). Two cases of amputation were done after 12 simultaneous infrainguinal bypasses, but 4 cases of after 10 staged infrainguinal bypasses. Operative mortality were 3 cases (4.7%). Conclusively, aortobifemoral bypass is still standard procedure in extensive aortoiliac occlusive disease in patients with low operative risk. And simultaneous infrainguinal bypass is preferred in patients with poor distal run-off. Alternatively, iliofemoral or extraanatomical bypasses are also considered case by case.

Chronic Abdominal Aortic Occlusion

Chronic abdominal aortic occlusion(CAO) is a rare entity and poses a particular management challenge. It shows a spectrum of clinical presentations due to chronic progression and suprarenal thrombus progression. Ongoing debate over the proximal thrombus propagation leading to renal and mesenteric artery occlusion results in controversy regarding the need of in-line aortic reconstruction with proximal thromboendarterectomy(TEA). To evaluate the management and surgical outcome of chronic abdominal aortic occlusion, a retrospective study of 24 patients surgically treated for angiographically documented CAO between September, 1986 and September, 1997 was conducted. Male to female ratio was 22:2 with a mean age of 56.8 years(range: 33~71 years). Mean follow-up period was 55.0 months. All patients presented with sympoms of vascular insufficiency of lower limbs including claudication in 10(41.7%), rest pain in 11(45.8%) and tissue loss in 3(12.5%). Impotence was present in 59.1% in men. Location of aortic occlusion was distributed in juxtarenal and above(11, 45.8%) and infrarenal(13, 54.2%). Associated visceral arterial involvement included 18 inferior mesenteric artery(IMA) occlusion, 8 renal artery(RA) stenosis and 1 superior mesenteric artery(SMA) occlusion. Infrainguinal arteries were involved in 11 patients(45.8%) including 9 superficial femoral artery obstruction. Aortobifemoral bypass(AoBF) grafts were implanted all but one case, which was treated with an axillobifemoral bypass(AxBF). In AoBF, proximal thrombectomy or thromboendarterectomy was performed and, in most cases, end to end anastomosis is favored in proximal anastomosis due to possibility of proximal thrombus propagation. Concomitant visceral revascularizations were performed in selected cases(2 renal, 2 IMA) with inflow procedures. The operative mortality rate was 4.2%(1/24) and the perioperative morbidity rate was 37.5%. AoBF inflow procedures yielded 1, 5-year primary patency rate of 95.5% and 89.1%, respectively. The one AxBF graft was occluded graft at 26 days after surgery. Two patients died and the 5-year survival rate for AoBF was 95.7%. There was no statistical change in renal function between pre- and postoperative periods. Follow-up renal dysfunction(serum creatinine levels>2.0 mg/dl) was documented in two patients, and one patient developed acute renal failure requiring dialysis. Aortobifemoral bypass following proximal thromboendarterectomy is the optimal treatment modality with high patency rate in chronic abdominal aortic occlusion. Visceral artery reconstruction in clinically significant stenosis and judicious attention for prevention of renal damage in pararenal thrombectomy under suprarenal clamping are helpful for better outcome in chronic abdominal aortic occlusion.