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Dive into the research topics where Sergio Kuzniec is active.

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Featured researches published by Sergio Kuzniec.


Clinical Autonomic Research | 2005

The body mass index and level of resection: predictive factors for compensatory sweating after sympathectomy.

José Ribas Milanez de Campos; Nelson Wolosker; Flavio Takeda; Paulo Kauffman; Sergio Kuzniec; Fabio Biscegli Jatene; Sérgio Almeida de Oliveira

ObjectiveCompensatory sweating (CS) is the most common adverse event and the main cause of dissatisfaction among patients undergoing a VATS sympathectomy for the treatment of primary hyperhidrosis. It has been described that obese individuals experience more sweating than thinner ones. The aim of this study is to identify the Body Mass Index (BMI) and the level of resection as predictive factors for CS and its relation to levels of patient satisfaction following the procedure.MethodsFrom October 1998 to June 2003, 102 patients undergoing VATS sympathectomies (51 for palmar hyperhidrosis, PH, and 51 for axillary hyperhidrosis, AH) were prospectively surveyed. They were divided into three groups according to their BMI: Group I was composed of 19 patients with BMI<20 (9 patients with PH and 10 with AH); Group II was composed of 52 patients with 20 ≤BMI<25 (25 with PH and 27 with AH); and Group III was composed of 31 patients with BMI ≥ 25 (17 with PH and 14 with AH). Each procedure was simultaneously and bilaterally performed under general anesthesia using two 5.5mm trocars and a 30° optic system.ResultsPatients treated for PH (resection of T2-T3) had more severe CS than those with AH (resection of T3-T4) (p=0.007) and the greater the BMI, the greater the severity of the CS (p<0.001). No statistically significant difference was found between the BMI bands in relation to the degree of satisfaction (p=0.644), nor when we compared the degree of satisfaction to the degree of CS (p=0.316).ConclusionsThe greater the BMI, the more severe the CS, but this did not correlate with the patients’ level of satisfaction. Avoiding the resection of T2 sympathetic ganglia is also important in reducing the intensity of CS.


Ophthalmology | 1997

Clinical Findings and Hemodynamic Changes Associated with Severe Occlusive Carotid Artery Disease

Vital Paulino Costa; Sergio Kuzniec; Lazlo J Molnar; Giovanni Guido Cerri; Pedro Puech-Leão; Celso Antonio de Carvalho

OBJECTIVE The purpose of the study was to evaluate the ophthalmologic findings and to analyze the retrobulbar hemodynamics of patients with severe (greater than 70% stenosis) occlusive carotid artery disease (OCAD) by means of color Doppler imaging (CDI). DESIGN A case-controlled study. PARTICIPANTS Fifty-six consecutive patients with severe OCAD and an age- and sex-matched control group consisting of 56 healthy patients without OCAD were studied. INTERVENTION All 112 patients underwent a complete ophthalmologic examination. Color Doppler imaging of both orbits was performed by one masked investigator. MAIN OUTCOME MEASURES Peak systolic velocity, end diastolic velocity, and the resistive index of the ophthalmic, central retinal, and temporal short posterior ciliary arteries were measured. The authors compared the hemodynamic parameters measured in patients with severe OCAD with those obtained in the control group. The hemodynamic parameters of patients with asymmetric OCAD (stenosis > 70% in one internal carotid artery and stenosis < 50% in the contralateral artery) were also compared. In an attempt to determine risk factors associated with the ocular ischemic syndrome (OIS), the authors compared patients with severe OCAD and OIS with patients with severe OCAD without OIS. RESULTS Peak systolic and end diastolic velocities in the ophthalmic, central retinal, and temporal short posterior ciliary arteries were significantly lower in patients with severe OCAD (P < 0.01). The mean resistive indices in the central retinal and temporal short posterior ciliary arteries were higher in the group with severe OCAD (P < 0.01). Similar results were obtained in the analysis of 25 patients with asymmetric carotid stenosis. Younger age (P = 0.012), severe bilateral OCAD (P = 0.01), high-grade carotid stenosis (P = 0.013), and reversed ophthalmic artery flow (P = 0.038) were significant risk factors for OIS. CONCLUSIONS Patients with severe OCAD show hemodynamic changes that suggest reduced retrobulbar blood flow. Patients with severe bilateral OCAD, high-grade carotid stenosis, and reversed ophthalmic artery flow may have a greater risk of developing OIS.


Cardiovascular Surgery | 1998

Diagnosis of limbs and neck arterial trauma using duplex ultrasonography

Sergio Kuzniec; Paulo Kauffman; Lazlo J Molnar; Ricardo Aun; Pedro Puech-Leão

OBJECTIVE To evaluate duplex ultrasonography for diagnosis of arterial trauma in limbs and neck. METHOD Fifty-one wounds in 47 patients, with indication for arteriography, were prospectively studied and grouped according to the presence (PCS group: 21 wounds, 41.2%) or absence (ACS group: 30 wounds, 58.8%) of clinical signs of arterial injury. All underwent duplex ultrasonography and arteriography. RESULTS Arteriography disclosed arterial injury in 21 wounds, of which 19 were visualized by duplex ultrasonography. In the other 30 wounds neither methods disclosed any arterial injury. The sensitivity of duplex ultrasonography was 90.5%, the specificity was 100% and the accuracy was 96.1%. In PCS group duplex ultrasonography showed 14 injuries (93.3%) and one false-negative result, and in ACS group, five injuries (83.3%) and one false-negative result in the ACS group. CONCLUSIONS Duplex ultrasonography reproduces the results of arteriography as a non-invasive diagnostic method in trauma of the limbs and neck.


Ophthalmology | 1999

The effects of carotid endarterectomy on the retrobulbar circulation of patients with severe occlusive carotid artery disease: An investigation by color Doppler imaging

Vital Paulino Costa; Sergio Kuzniec; Lazlo J Molnar; Giovanni Guido Cerri; Pedro Puech-Leão; Celso Antonio de Carvalho

OBJECTIVE To analyze the effects of carotid endarterectomy on the retrobulbar circulation of patients with severe occlusive carotid artery disease (OCAD) by means of color Doppler imaging (CDI). DESIGN Prospective. PARTICIPANTS A total of 17 consecutive patients with severe OCAD and neurologic symptoms (with a history of transitory ischemic attack or cerebral vascular accident) participated. INTERVENTION All 17 patients underwent carotid endarterectomy. The CDI of both orbits was performed by one masked investigator before surgery and at 1 week and 1 month after surgery. MAIN OUTCOME MEASURES Peak systolic velocity, end diastolic velocity, and resistive index of the ophthalmic, central retinal, and temporal short posterior ciliary arteries were measured. The authors compared the hemodynamic parameters at all intervals. RESULTS Peak systolic and end diastolic velocities in the ophthalmic, central retinal, and temporal short posterior ciliary arteries increased significantly 1 week and 1 month after carotid endarterectomy (P < 0.05). After surgery, the resistive indices in the central retinal and temporal short posterior ciliary arteries decreased significantly at both intervals (P < 0.05). The six patients who had reversed ophthalmic artery flow before surgery showed forward ophthalmic artery flow after carotid endarterectomy. The contralateral orbits showed no significant hemodynamic change after endarterectomy (P < 0.05). CONCLUSIONS Hemodynamic changes in patients with severe OCAD undergoing carotid endarterectomy suggest improvement in the ipsilateral retrobulbar blood flow.


Ophthalmology | 1998

Collateral blood supply through the ophthalmic artery: A steal phenomenon analyzed by color Doppler imaging

Vital Paulino Costa; Sergio Kuzniec; Lazlo J Molnar; Giovanni Guido Cerri; Pedro Puech-Leão; Celso Antonio de Carvalho

OBJECTIVE This study aimed to evaluate the retrobulbar circulatory effects of reversed ophthalmic artery flow (ROAF) on the ophthalmic artery branches by means of color Doppler imaging. DESIGN The design was a case-controlled study. PARTICIPANTS Among 56 consecutive patients with severe (>70% stenosis) occlusive carotid artery disease, 15 patients (26.8%) with ROAF were identified. The control group consisted of 15 patients with similar degrees of carotid artery stenosis and forward ophthalmic artery flow. INTERVENTION Arteriography and measurement of the retrobulbar hemodynamic parameters with color Doppler imaging were performed. MAIN OUTCOME MEASURES Blood flow velocities and resistive index in the ophthalmic, central retinal, and temporal short posterior ciliary arteries were measured. RESULTS Arteriography confirmed the diagnosis of ROAF in all 15 patients. There was no patient with ROAF diagnosed by arteriography and not diagnosed by color Doppler imaging. The frequency of bilateral severe occlusive carotid artery disease was significantly higher in the ROAF group (40%) compared to the control group (6.6%) (P = 0.04). Patients with ROAF showed significantly reduced vascular resistance in the ophthalmic artery (P = 0.03), higher vascular resistance, and lower blood flow velocities in the central retinal and temporal short posterior ciliary arteries (P < 0.05). CONCLUSION This study suggests that patients with ROAF show a steal phenomenon, characterized by a shunt to the low-resistance intracranial circuit and reduction of retrobulbar blood flow.


Annals of Vascular Surgery | 2013

Technical Difficulties and Complications of Sympathectomy in the Treatment of Hyperhidrosis: An Analysis of 1731 Cases

Laert Oliveira de Andrade Filho; Sergio Kuzniec; Nelson Wolosker; Guilherme Yazbek; Paulo Kauffman; José Ribas Milanez de Campos

BACKGROUND The aim of this study was to ascertain the technical difficulties and complications of video-assisted thoracic sympathectomy (VTAS) in the treatment of hyperhidrosis in a large group of patients. METHODS Between October 1995 and February 2008, 1731 patients with palmar, axillary, or craniofacial hyperhidrosis, who were treated using bilateral VTAS, were studied. We assessed the technical difficulties, early and late complications, and the approaches that were used to resolve them. RESULTS Therapeutic success was achieved in 91% of the cases as evidenced by anhidrosis. The most common and severe technical difficulty during the procedure was pleural adhesions in 116 cases (6.7%); azygos lobes were seen in 7 patients (0.4%) and apical blebs in 3 patients (0.2%). The most frequent postoperative immediate complication was postoperative pain in 1685 (97.4%) patients; pneumothorax with chest drainage was seen in 60 cases (3.5%), neurologic disorders involving the upper limbs in 36 cases (2.1%), Horners syndrome in 11 cases (0.9%), significant bleeding in 8 cases (0.4%), and 1 patient had extensive subcutaneous emphysema. The most frequent late complication was compensatory hyperhidrosis, which occurred in 1531 cases (88.4%). Although 27.2% of the patients reported severe compensatory hyperhidrosis, only 2.5% expressed regret for undergoing surgery. Gustatory sweating occurred in 334 patients (19.3%). No deaths occurred in this series. CONCLUSIONS VTAS is safe and has shown good results. The major complication is compensatory hyperhidrosis and, when severe, the patient may express regret for undergoing surgery. Improvements in instrumentation, adequate training, and careful patient selection may help to reduce the number of drawbacks associated with VTAS.


Journal of Vascular Surgery | 2010

Videothoracoscopic-guided management of a central vein perforation during hemodialysis catheter placement

Sergio Kuzniec; Sílvia Regina Bottini Natal; Eduardo de Campos Werebe; Nelson Wolosker

We present a case of the successful repair of an iatrogenic central vein lesion using a videothoracoscopic approach. The confluence of the right innominate vein and the superior vena cava was perforated during the placement of a right internal jugular vein long-term dialysis catheter. The misplacement of the tips of the catheter in the right pleural space was promptly observed. The catheter was removed under pleural videothoracoscopic vision while a tamponade was directly applied to the mediastinal perforation. Massive bleeding was prevented and the central vein perforation was treated successfully using a minimally invasive technique.


Annals of Vascular Surgery | 2014

Carbon dioxide is a cost-effective contrast medium to guide revascularization of TASC A and TASC B femoropopliteal occlusive disease.

Cynthia de Almeida Mendes; Alexandre de Arruda Martins; Marcelo Passos Teivelis; Sergio Kuzniec; Kenji Nishinari; Mariana Krutman; Hélio Halpern; Nelson Wolosker

BACKGROUND Iodine contrast medium (ICM) is considered gold standard in endovascular revascularization procedures. However, nephrotoxicity and hypersensitivity to ICM are causes that limit its indiscriminate use. Carbon dioxide (CO2) contrast angiography has been used as an alternative in patients with formal contraindication to ICM. However, no studies to the present date have compared in a randomized and prospective way, outcomes of revascularization procedures performed with either ICM or CO2 in patients eligible for use of both contrasts. METHODS Between April 2012 and April 2013, 35 patients with peripheral arterial disease with arterial lesions classified as Trans-Atlantic Inter-Society Consensus A or B (identified on preoperative angio computed tomography scan) and adequate runoff underwent femoropopliteal revascularization by endovascular technique in a prospective, randomized, and controlled study. Patients were randomized into 2 groups: CO2 group and ICM group, according to the contrast media selected of the procedure. We evaluated the following outcomes in both groups: feasibility of the procedures, complications, surgical outcomes (ankle-brachial index [ABI]), glomerular filtration rate using the Cockcroft-Gault formula, relationship between the volume of injected iodine and postoperative creatinine clearance, quality of the angiographic images obtained with CO2, costs of the endovascular materials, and finally, cost of contrast agents. RESULTS We were able to perform the proposed procedures in all patients treated in this series (ICM group and CO2). There were no CO2-related complications. No procedures required conversion to open surgery. Clinical results were satisfactory, with regression of ischemia and increased levels of ABI in both groups. Variations in creatinine clearance levels showed a numerical increase in the CO2 group and a decrease in ICM group, however, with no statistically significant difference between the delta clearance in each group. All CO2 arteriograms of the supragenicular arteries were graded as good or fair by both observers with high interobserver image quality concordance. There was no statistical difference between endovascular material costs between the groups, but the contrast cost was significantly lower in CO2 group (P < 0.001). CONCLUSIONS The use of CO2 in patients with no restriction for ICM is an alternative that does not limit the feasibility of the procedures. Similar outcomes were observed with CO2 when compared with the gold standard contrast (ICM) regarding quality of images produced, with no associated changes in creatinine clearance or hypersensitivity reactions and also allows a reduction in contrast-related costs in angioplasty procedures.


Sao Paulo Medical Journal | 1996

Arterial embolectomy in lower limbs

Nelson Wolosker; Sergio Kuzniec; Álvaro Gaudêncio; Luis Ricardo Amaral Salles; Ruben Miguel Ayzin Rosoky; Ricardo Aun; Pedro Puech-Leão

Arterial embolisms in the lower limbs occur frequently, and are of great interest to the vascular surgeon. The authors studied 159 cases of arterial embolisms in lower limbs from January 1991 to July 1993. Ages varied from 12 to 98, with a mean of 58. Eighty patients were male and 78 were female. In most cases, etiology of the embolus was well-established, and mainly caused (78 percent) by atrial fibrillation. Occlusion was most frequent in the femoral artery (53.4 percent). All patients presented severe lower limb ischemia, but not gangrene, on admission. The duration of ischemia, between the onset of symptoms and the liberation of arterial flow, was in most patients (67.9 percent) less than 24 hours. All patients were submitted to lower limb embolectomy with the Fogarty catheter, of which 70.9 percent were done through the femoral artery. Fasciotomy was performed on 48 patients due to a compartimental syndrome. Nineteen patients died immediately after operation; 68.4 percent due to heart failure. Twenty-three (16.4 percent) of the 140 surviving patients (150 operated limbs) were submitted to amputations after the occlusion of artery branches, which had undergone embolectomies. One hundred and twenty-seven limbs (84.6 percent) were preserved in 117 patients (83.5 percent). Eleven cases (7.3 percent) required repeated surgery with the Fogarty catheter. The patients with muscle tenderness, paralysis, or ischemia lasting longer than 24 hours had worse results in relation to the preservation of the limb (p < 0.05). We conclude that patients who present lower limb embolisms, are in good clinical condition, and who do not have any necrosis in the limbs, have good outcomes as to limb preservation, along with low complication rates, after embolectomy with the Fogarty catheter. Limb preservation was significantly higher in patients who did not present muscle tenderness, and who had normal motor activity and a ischemia duration of less than 24 hours.


Annals of Vascular Surgery | 2017

Carbon dioxide as contrast medium to guide endovascular aortic aneurysm repair.

Cynthia de Almeida Mendes; Alexandre de Arruda Martins; Marcelo Passos Teivelis; Sergio Kuzniec; Andrea Yasbek Monteiro Varella; Nelson Wolosker

BACKGROUND Iodine contrast medium (ICM) is considered to be gold standard in endovascular procedures, but its nephrotoxicity and hypersensitivity limit the widespread use. Carbon dioxide (CO2) is considered as an alternative for endovascular procedures in patients with contraindication to ICM. However, no studies have compared the outcomes of endovascular aneurysm repair (EVAR) performed with ICM or CO2 among patients with no contraindication to ICM. METHODS From May 2012 to April 2014, 36 patients with abdominal aortic aneurysms underwent EVAR in a prospective, randomized, and controlled study. Patients were randomized into 2 groups, CO2 or ICM group. RESULTS We were able to perform the proposed procedures in all patients in this study. There were no conversions to open surgery and no CO2-related complications. Endovascular material costs, duration of surgery, and time of fluoroscopy were similar between groups, and the cost of the contrast media was smaller in the CO2 group than in the ICM group. Among CO2 group procedures, 62.5% of the patients needed ICM complementary use. CONCLUSIONS The use of CO2 as a contrast medium for EVAR is an alternative in patients with no restriction for ICM, with similar outcomes when compared to ICM, regarding duration of surgery, duration of fluoroscopy, and endovascular material costs. Using CO2, there were no changes in creatinine clearance and no risk of hypersensitivity reactions; moreover, there was a reduction in contrast-related costs for EVAR procedures. However, in our study, additional use of ICM to visualize the internal iliac artery was needed in most procedures.

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Paulo Kauffman

University of São Paulo

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Ricardo Aun

University of São Paulo

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Lazlo J Molnar

University of São Paulo

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