Evaluation of two anesthetic techniques for hemodynamic control during carotid surgery. Preliminary results.

BACKGROUND: To evaluate two anesthetic techniques for hemodynamic control during carotid TEA surgery and early post-surgery. METHODS: Two study groups treated by carotid surgery were compared; the Fentanyl group consisted of 7 patients in ASA class 3, the Remifentanil-Sevoflorane group included 12 patients in ASA class 3. The double product was monitored on entry to the operating room, at 5, 15, 30 min after induction of anesthesia and tracheal intubation, and at 30 min after extubation. Time of extubation, re-awakening and attention levels during early post-surgery, and myocardial ischemia markers were monitored for 48 h after surgery in the Remifentanil group. RESULTS: Statistical analysis using Student's "t"-test for paired data showed that the double product indicated better hemodynamic stability in the patients who received Remifentanil-Sevoflorane than in those who received Fentanyl. CONCLUSIONS: Compared with anesthesia using Fentanyl and with locoregional techniques, anesthesia with Remifentanil-Sevoflorane in carotid surgery provides a valuable alternative and secures good hemodynamic stability.

Short-term arterial blood reperfusion of normothermic kidney in renal artery and abdominal aorta reconstructive surgery.

OBJECTIVE: to prevent kidney injury in renal artery and juxta-renal aortic surgery. After 30 min of cross-clamping ischaemia, renal arterial inflow is temporary re-established for 3 min. The aim of the study was to retrospectively analyse the results of this original technique. METHODS: between January 1987 and May 1999, 48 patients underwent kidney short-term arterial blood reperfusion, directly or through the Pruitt-Inahara shunt. The reperfusion was repeated every 30 min of ischaemia, whenever necessary. Fifty control patients underwent <30 min of kidney ischaemia. Patients were assessed by serum creatinine, digital angiography and radioisotope renography using technecium(99). RESULTS: in the study group one patient developed an acute renal failure and died (2% (-95% CI: 0-11%)). In both study and control groups patients showed a similar and moderate but temporary decline in renal function, which returned to preoperative levels after 1 week. CONCLUSIONS: the results of this study indicate that kidney short-term reperfusion may protect renal tissue from prolonged cross-clamping ischaemia (up to 100 min), also in patients considered at high risk for acute renal failure.

Carotid endarterectomy without angiography: a prospective randomised pilot study.

OBJECTIVES: to determine whether duplex ultrasonography alone is an adequate examination prior to carotid endarterectomy. DESIGN: prospective, randomised, single centre study. MATERIAL AND METHODS: all patients with carotid bifurcation stenosis greater than 70% - based on duplex scanning - were randomised to arteriography followed by carotid surgery (Group A n=96) or carotid surgery alone (Group B n=90). Study endpoints were neurological complications or death occurring between the day of randomisation and until 30 days after surgery. RESULTS: major neurological complications of death in 1 (1%) vs 3 (3.3%) patients in group A and B, respectively (n.s.). Minor neurological complications (only TIA) were observed in 0 and 3 (3.3%) patients, respectively. CONCLUSIONS: complication rates were low in both groups and within the generally accepted rate after carotid surgery in asymptomatic and symptomatic patients.

Clamping ischemia, threshold ischemia and delayed insertion of the shunt during carotid endarterectomy with patch.

BACKGROUND: Shunt insertion during carotid endarterectomy (CEA) is mandatory to avoid neurological damage due to clamping ischemia; however shunt insertion before plaque removal has many inconveniences (atheroembolism, intimal dissection, difficulty of endarterectomy). The aim of this study is to verify whether and how long shunt insertion may be safely delayed to permit plaque removal and ensure cerebral perfusion during the further time consuming manoeuvres of CEA (peeling, patch angioplasty). METHODS: From July 1990 to February 1996 383 patients underwent 411 CEAs under general anesthesia with EEG continuous monitoring and PTFE patch angioplasty. A Pruitt-Inahara shunt was routinely inserted only after atherosclerotic plaque removal. In 316 CEAs (76.9%) without EEG signs of cerebral ischemia (Group A) the mean clamping time was 10 min +/-4.8 (range 2-37 min). In 95 CEAs (23.1%) with EEG signs of cerebral ischemia (Group B) it was 7.3 min +/-3.5 (range 3-20 min). All patients had normal EEG signals after delayed shunt insertion and reperfusion (mean 21 min, range 5-45 min). RESULTS: In the short term results (within 30 days) there was a relevant neurological complication rate of 0.96% (2 major stroke and 2 lethal stroke); at awakening we observed 5 RINDs (1.21% of total) 1 in a patient of Group A (0.31%) and the other 4 in patients of Group B (4.21%). CONCLUSIONS: These data confirm the rationale of a delayed insertion of the shunt: actually the cerebral parenchyma may tolerate under general anesthesia a sufferance due to carotid clamping, EEG detectable, without neurological deficits for at least 7.3 min. This time is sufficient to perform the most difficult steps of CEA (plaque removal, distal intima checking) allowing shunt insertion in a clean operatory field, without inconveniences. Finally the shunt allows complementary time consuming steps, as patch angioplasty, with improvement of both short- and long-term results.

Surgical treatment of atherosclerotic lesions of subclavian artery: carotid-subclavian bypass versus subclavian-carotid transposition.

BACKGROUND: The aim of this retrospective study is to analyze the short and long term results of two different surgical treatments in patients with subclavian lesions: common carotid-subclavian artery bypass (CSB) versus transposition of subclavian artery on the common carotid artery (SCT). METHODS: From 1981 until 1995, 40 non randomized patients with symptomatic subclavian steal underwent 20 CSBs and 20 SCTs. Risk factor rates were equally balanced in the two groups. Surgery was carried out routinely under general anesthesia, with electroencephalic continuous monitoring. Patency of revascularization was assessed by physical examination, brachial blood pressure determinations, ultrasound sonography and angiography whenever recurrence of symptoms developed or when the function of repair was in doubt. Patients were examined every year. In Spring 1996 (range 9-189 mos, average 7 years) a general clinical-instrumental follow-up was performed. RESULTS: In the short term (<30 days) mortality was 5%: one death (5%) for pulmonary embolism in a patient with CSB and one for myocardial infarction in a patient with SCT. The early thrombosis rate was 5% (1 CSB and 1 common carotid artery distal to a patent SCT). During follow-up 10 patients (25%) died and 6 were lost. The six-year actuarial patency rate was 100% for SCT and 66% for CSB. Moreover there were 3 thromboses of the vertebral artery homolateral to patent CSBs. CONCLUSIONS: In conclusions SCT should be considered the surgical technical choice for the treatment of proximal subclavian artery lesions.

Carotid artery endarterectomy in patients with contralateral carotid artery occlusion: perioperative hazards and late results.

The aim of this study was to analyze and compare the perioperative hazards and late results of internal carotid endarterectomy (CEA) in patients with and without contralateral internal carotid artery occlusion. From March 1980 to April 1990, 375 consecutive patients underwent 439 CEAs at the First Department of Vascular Surgery of Padova Medical School. Patients were divided into two groups; group 1 (61 patients) had contralateral internal carotid artery occlusion and group 2 (314 patients) did not (378 CEAs, 64 bilateral). Indications for CEA were similar in both groups. The only significant difference in patient characteristics was a higher rate of previous stroke in group 1 (11% vs. 3%, p < 0.001). General anesthesia, continuous EEG monitoring, selective intraluminal shunt, and arteriotomy closure with a polytetrafluoroethylene patch (PTFE) were used routinely in both groups. An intraluminal shunt was inserted more frequently in group 1 than in group 2 (69% vs. 17%, p < 0.001). Major perioperative stroke occurred in one patient in each group (1.7% vs. 0.31%, respectively; NS). Early fatal stroke rates were 0% and 0.95% in groups 1 and 2, respectively (NS). All patients had neurologic examinations and duplex scans every 6 months (range 6 to 118 months; mean 42 months). Kaplan-Meier survival curves were virtually identical in the two groups; the majority of deaths were caused by myocardial infarction and cancer. There were no stroke-related deaths in group 1 as compared with 8.2% in group 2 (NS). New neurologic symptoms appeared in 4.7% of patients in group 1 and 6% in group 2 (NS) whereas the late stroke rates were 0% and 3.1%, respectively (NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of high-grade stenosis of innominate artery.

Although pathology of the innominate artery (IA) is not frequent, it causes relevant impairment of extracranial circulation and sometimes cerebrovascular events. Definite differentiation of high-grade stenosis from occlusion of the IA has not been obtained until now with continuous-wave (C.W.) Doppler and duplex system ultrasound, and thus the direct evaluation of IA is not reliable by noninvasive methods. In this study the authors suggest an indirect method of evaluation of IA pathology based on the study of carotid, subclavian, and vertebral arteries (VA) with echo-Doppler-color-flow (EDCF) (with linear--phase array probes of 7.5 and 5 MHz). In the last two years they studied 6 patients with IA pathology (2 with occlusion (occ), 1 with stenosis of 80% and 3 with subocclusive stenosis > 90%). In both patients with occ, right VA flow was inverted, and also the right common carotid (CC) was involved (occ in 1 case and inverted flow in the other); in the 3 subocclusive stenoses a lowered systolic flow in the CC was recorded (48 vs 85 cm/sec, 41 vs 77, and 23 vs 109). In the 80% stenosis, besides the inverted flow in VA, only a reduced diastolic flow in CC was also recorded (19 vs 33 cm/sec measured in the left side). All patients with high grade stenosis were successfully confirmed by an angiographic study, including the different degree of stenosis. Five of the 6 patients underwent surgical correction with a restored flow in the previously involved artery. Only 1 patient with occlusion is waiting for surgical correction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Indications for revascularization procedures in patients with intermittent claudication]. / Indicazioni all'intervento di rivascolarizzazione nei pazienti con claudicatio intermittens.

Patients suffering from arteriosclerotic obliterating disease of the lower limbs that present with symptoms of rest pain, ulcers or more or less severe gangrene are considered as candidates for revascularization operation. Apart from the possible non relevance of individual symptoms, in some instances the revascularization operation is indicated solely on the basis of the angiographic evidence. Ascending thrombosis of the abdominal aorta, double or triple blocks, stenosis of the collateral circulation and, broadly speaking, any other situation that suggests a possible superimposition of an episode of acute ischaemia due to thrombosis in a condition of chronic obliterating arteriopathy are considered as absolute indication for revascularization operation. Patients whose conditions are not listed above are considered as stage II and indication for operation in this case is not absolute but relative or "luxury" since its purpose is only to improve the quality of life. The importance of the symptoms must be considered along with other factors, including the personal, social, working, sporting and psychological needs of the specific individual apart from the absence of general risks related to the patient's condition. The vascular surgeon's expertise is obviously fundamental in exactly evaluating the arteriography and in understanding the precise anatomic picture that varies in every single case: in fact, since the operation is optional and not a necessity, correction of the arterial lesions in only advisable when it is possible to carry out and operation that is broadly risk free and with good short and long term results, with reference to the patient's life expectancy.

[Carotid stenosis and obliteration of the contralateral carotid. A prospective study of the risks of a carotid endarterectomy intervention and its long-term results]. / Stenosi carotidea ed obliterazione della carotide controlaterale. Studio prospettico sui rischi dell'intervento di endoarteriectomia carotidea e sui risultati a distanza.

From March 1980 to July 1988 a consecutive series of 256 patients (p.) underwent 301 carotid endarterectomy + patch with routine use of continuous intraoperative EEG monitoring and selective use of an intraluminal shunt (IS) for the presence of an atherosclerotic plaque concerning the internal carotid artery (ICA). Patients were divided in two groups: the first (42 p.) marked by contralateral ICA occlusion, the second (214 p.) without contralateral ICA occlusion (259 CEA). Immediate peroperative, long term and global (immediate and long term) outcomes were prospectively and comparatively studied. A temporary IS was inserted in 27 p. (64%) of the group I and in 38 p. (14%) of the group II. Immediate permanent postoperative neurological deficit occurred in 1 p. of group I (2.38%) and in 2 p. (0.9%) in group II. Immediate postoperative mortality was 0% and 0.9% in group I and II respectively. All p. had neurological valuation and Echo-Doppler of operated ICA and of the contralateral ICA every 6 months (middle follow-up 44 months). New neurological symptoms compared in 5.8% of p. of group I and in 5.23% of p. of group II with a stroke rate of 0% and 2.32% respectively. There were 2 restenosis of operated ICA, both of them in p. of group I, that underwent reoperation. In the two groups the principal causes of deaths were myocardial infarct and cancer; in the group I no death was due to stroke versus 1.86% in the group II.

EEG monitoring, selective shunting and patch graft angioplasty in carotid endarterectomy. Early and longterm results.

From March 1980 to July 1986 at the Department of Vascular Surgery of the University of Padua, 182 patients underwent 210 carotid revascularizations for atherosclerotic stenosis involving the carotid bifurcation (28 operations were bilateral). Carotid endarterectomies (CE) and patch graft angioplasty totalled 192 (166 patients); an enlarging patch graft angioplasty of the internal carotid artery (ICA) without CE was performed in 14 cases (13 patients); in the remaining four surgical procedures (3 patients), for technical reasons prohibiting CE, the operation consisted of a great saphenous vein bypass between a donor vessel and the ICA distal to the lesion. The preoperative symptoms in 182 patients were as follows: TIAs (98 cases, 54%), non-hemispheric symptoms (21 cases (12%) and fixed stroke or TIAIR (10 cases, 5%). Fifty-three patients (29%) were asymptomatic. In all cases, continuous EEG monitoring was employed. The operation was performed without a temporary intraluminal shunt in the patients showing tolerance to carotid clamping. The protection of the shunt was required only in patients with EEG changes (47 cases). The arteriotomy was routinely closed with a PTFE patch graft angioplasty. Early results of the operation were excellent: none of the patients presented permanent or transient neurological deficits in the immediate postoperative period and none of them died. All patients were reassessed with C.W. Doppler sonography and Duplex scanning in the postoperative period. In all cases, the success of the operation was demonstrated. Longterm follow-up (6-72 months, mean follow-up: 35 months) was done in 121 patients (142 operations): 107 patients were completely asymptomatic, 5 remained stable or slightly improved the preoperative status. Five patients had a new or recurrent TIAs, 3 suffered a stroke, one showed a recurrence of non-hemispheric symptoms. With the exception of two patients suffering a stroke, all had a second arteriography but none of these patients showed extracranial lesions. Two patients presented an asymptomatic restenosis of the ICA. Eight patients (8.8%) revealed a significant evolution of the disease of the contralateral unoperated ICA.(ABSTRACT TRUNCATED AT 400 WORDS)

[Continuous EEG monitoring in carotid surgery]. / Il monitoraggio EEG continuo in chirurgia carotidea.

From March 1980 to March 1987, at the Department of Vascular Surgery of the University of Padua, 217 patients underwent 252 carotid revascularizations with routine use of an intraluminal shunt (IS) for symptomatic (70%) or asymptomatic (30%) internal carotid artery (ICA) atherosclerotic stenosis. All carotid endarterectomies (CEs) were routinely performed with patch graft angioplasty to prevent restenosis. In the immediate post-operative period, no patient presented permanent or transient neurological deficits; no patient died. In the early post-operative course there was a 0.9% (2 patients) stroke rate and 0.4% (1 patient) mortality rate. These results suggest that the selective use of the IS on the basis of EEG changes is able to reduce the perioperative morbidity and mortality to nearly zero.