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991.
PURPOSE: To our knowledge we present the initial clinical report of hand assisted laparoscopic radical nephrectomy for renal cell carcinoma with tumor thrombus extending into the inferior vena cava. MATERIALS AND METHODS: A 76-year-old man was referred to our medical center with a 12.5 x 10 cm. stage T3b right renal tumor extending into the inferior vena cava. The caval thrombus was limited and completely below the level of the hepatic veins. After preoperative renal embolization via the hand assisted transperitoneal approach the right kidney was completely dissected with the renal hilum. Proximal and distal control of the inferior vena cava was obtained with vessel loops and a single lumbar vein was divided between clips. An endoscopic Satinsky vascular clamp was placed on the inferior vena cava just beyond its juncture with the right renal vein, thereby, encompassing the caval thrombus. The inferior vena cava was opened above the Satinsky clamp and a cuff of the inferior vena cava was removed contiguous with the renal vein. The inferior vena cava was repaired with continuous 4-zero vascular polypropylene suture and the Satinsky clamp was then removed. A literature search failed to reveal any similar reports of laparoscopic radical nephrectomy for stage T3b renal cell cancer. RESULTS: Surgery was completed without complication with an estimated 500 cc blood loss. Pathological testing confirmed stage T3b grade 3 renal adenocarcinoma with negative inferior vena caval and soft tissue margins. CONCLUSIONS: The introduction of vascular laparoscopic instrumentation and the hand assisted approach enabled us to extend the indications for laparoscopic radical nephrectomy to patients with minimal inferior venal caval involvement.  相似文献   
992.
OBJECT: The effects of the adenosine receptor antagonists theophylline (for A1 and A2) and ZM 241385 (for A2A) on hippocampal injury and Morris water maze (MWM) performance in rats were investigated following normoglycemic and hyperglycemic cerebral ischemia (induced by four vessel occlusion for 10 minutes). METHODS: Theophylline (36 mg/kg), ZM 241385 (1 mg/kg), or an equivalent volume of saline was administered to rats intraperitoneally 30 minutes before ischemia was induced. Moderate hyperglycemia was achieved by intraperitoneal administration of D-glucose (3 g/kg, 15 minutes before induction of ischemia). Morris water maze trials were performed on the 6th. 7th, and 8th days after ischemic insult. After the conclusion of the performance tests, the rat brains were cut into 8-microm sections, stained with cresyl violet and acid fuchsin, and evaluated in a blinded fashion to determine the extent of injury. Theophylline worsened injury in the hippocampus following normoglycemic and hyperglycemic ischemia. Moreover, theophylline significantly (p < 0.05, six animals) worsened latency and learning index (LI) scores during the MWM trials in both normoglycemic and hyperglycemic animals. On the other hand, ZM 241385 had no effect on either ischemic injury or MWM performance in normoglycemic animals. In the animals in the hyperglycemic ischemia group, however, ZM 241385 significantly (p < 0.05, five animals) reduced injury in the CA1 (94.6 +/- 1.7% compared with 79.2 +/- 10.9%), CA3 (26 +/- 12.5% compared with 11.2 +/- 4.3%), and hilum (22.4 +/- 8.1% compared with 11 +/- 5.5%) regions. In addition, ZM 241385 significantly improved latency (52 +/- 29.7 seconds compared with 24.8 +/- 11.2 seconds, p < 0.05) and LI scores (203.2 +/- 33.3 compared with 152.1 +/- 31.8, p < 0.05) in the MWM trials. A statistically significant correlation was also found between hippocampal injury (CA1, CA3, and hilum) and MWM performance. CONCLUSIONS: The results of this study provide further evidence for a neuromodulatory role of adenosine during normoglycemic and hyperglycemic ischemia.  相似文献   
993.
Chest wall resections and reconstruction: a 25-year experience   总被引:11,自引:0,他引:11  
Background. Chest wall defects continue to present a complicated treatment scenario for thoracic and reconstructive surgeons. The purpose of this study is to report our 25-year experience with chest wall resections and reconstructions.

Methods. A retrospective review of 200 patients who had chest wall resections from 1975 to 2000 was performed.

Results. Patient demographics included tobacco abuse, hypertension, diabetes mellitus, alcohol abuse, coronary artery disease, chronic obstructive pulmonary disease, and human immunodeficiency virus. Surgical indications included lung cancer, breast cancer, chest wall tumors, and severe pectus deformities. Twenty-nine patients had radiation necrosis and 31 patients had lung or chest wall infections. The mean number of ribs resected was 4 ± 2 ribs. Fifty-six patients underwent sternal resections. In addition 14 patients underwent forequarter amputations. Immediate closure was performed in 195 patients whereas delayed closure was performed in 5 patients. Primary repair without the use of reconstructive techniques was possible in 43 patients. Synthetic chest wall reconstruction was performed using Prolene mesh, Marlex mesh, methyl methacrylate sandwich, Vicryl mesh, and polytetrafluoroethylene. Flaps utilized for soft tissue coverage were free flap (17 patients) and pedicled flap (96 patients). Mean postoperative length of stay was 14 ± 14 days. Mean intensive care unit stay was 5 ± 9 days. In-hospital and 30-day survival was 93%.

Conclusions. Chest wall resection with reconstruction utilizing synthetic mesh or local muscle flaps can be performed as a safe, effective one-stage surgical procedure for a variety of major chest wall defects.  相似文献   

994.
Background. Native valve endocarditis is frequently managed with antibiotics alone, but prosthetic valve endocarditis usually requires an early operation. What is the best treatment of endocarditis after mitral valve repair?

Methods. From 1986 to 2000, 22 patients were treated for endocarditis affecting a previously repaired mitral valve. Causes of mitral valve dysfunction that led to repair were degenerative (11 patients), ischemic (5 patients), endocarditic (3 patients), rheumatic (2 patients), and functional (1 patient). Endocarditis was active in 21 patients and healed in 1. Interval from initial mitral valve repair to onset of endocarditis ranged from 1 week to 10.3 years (median, 6 months). Pathology included leaflet vegetation (15), annuloplasty vegetation (4), leaflet perforation (5), and abscess (3). Mean follow-up was 3.9 ± 3.3 years.

Results. Fifteen patients underwent repeat mitral valve operations with freedom from mitral valve reoperation of 65%, 41%, and 26% at 30 days, 1 year, and 5 years after onset of endocarditis. After a high early hazard, risk of reoperation fell to 10.8% per year. Seven patients, all with a leaflet vegetation, were treated with antibiotics alone. Antibiotics eradicated infection in all; however all had mitral regurgitation 2+ to 4+. Survival was 96%, 74%, and 68% at 30 days, 1 year, and 5 years. Endocarditis recurred in 1 patient (92% free of event).

Conclusions. Most patients that have endocarditis develop after mitral valve repair require reoperation. However if infection is limited to a leaflet, early reoperation may be unnecessary because antibiotics alone can eradicate infection.  相似文献   

995.
Using switching detection and variational equations for the shooting method   总被引:1,自引:0,他引:1  
We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
996.
Berkenbosch JW  Fichter CR  Tobias JD 《Anesthesia and analgesia》2002,94(3):506-11; table of contents
In patients who are mechanically ventilated in the pediatric intensive care unit (PICU), sedative and/or analgesic medications are routinely provided and titrated to effect based on clinical assessment of the patient. The bispectral index (BIS) monitor uses a modified electroencephalogram to quantify the effects of central nervous system-acting drugs on the level of consciousness. To evaluate the usefulness of the BIS monitor to predict clinical sedation levels in the PICU, we compared BIS values with simultaneously obtained clinical sedation scores in 24 mechanically ventilated pediatric patients aged 5.7 plus minus 6.1 yr. For each sedation scale used, the BIS value correlated with increasing depth of sedation (P < 0.0001) and was independent of the drug(s) used for sedation. To differentiate adequate from inadequate sedation, a BIS value <70 had a sensitivity of 0.87--0.89 and a positive predictive value of 0.68--0.84. To differentiate adequate from excessive sedation, a BIS value <50 had a sensitivity of 0.67--0.75 and a positive predictive value of 0.07--0.52. We conclude that the BIS monitor may be a useful adjunct for the assessment of sedation in PICU patients. IMPLICATIONS: We demonstrate the usefulness of the bispectral index monitor for assessing sedation in pediatric intensive care unit patients. The bispectral index monitor correlated with clinically assessed sedation levels and was useful for differentiating adequate from inadequate sedation, which would be of value when the clinical examination is unavailable.  相似文献   
997.
How malunion of the distal radius affects the kinematics of the distal radioulnar joint in vivo was evaluated. A novel computed tomography image-based technique was used to quantify radioulnar motion in both wrists of 9 patients who had unilateral malunited distal radius fractures. In the injured wrists dorsal angulation averaged 21 degrees +/- 6 degrees, radial inclination averaged 18 degrees +/- 5 degrees, and radial shortening averaged 21 +/- 3 mm. Clinically, the average range of motion of the injured wrists was 75 degrees +/- 25 degrees pronation and 73 degrees +/- 23 degrees supination. Kinematics of the radius during pronation and supination in the malunited forearms was indistinguishable from that in the uninjured forearms. In both the axis of rotation of the radius passed through the center of the ulnar head, although it shifted slightly ulnar and volar in supination and radial and dorsal during pronation. In contrast to previous in vitro biomechanical findings, there was no dorsovolar radial translation at the extremes of pronation or supination and no translation of the radius along the rotation axis. Soft tissues may play a larger role in limiting function than previously appreciated, and treatment may require correction of altered soft tissue structures as well as any abnormal bone anatomy.  相似文献   
998.
OBJECTIVE: The development of a thoracoscopically assisted technique to be performed with the patient under local anesthesia for both diagnostic and therapeutic purposes when treating pleural effusions and empyemas in high-risk surgical patients. METHODS: Twenty patients with pleural effusion or empyema who were also determined to be at high risk for complications following a thoracotomy, pleural biopsy, general anesthesia, or all of these, underwent placement of a thoracoscope while under local anesthesia followed by thoracic fluid drainage, pleural biopsy, and pleurodesis as required. Patients were retrospectively evaluated for a variety of factors including personal history, pre-existing medical conditions, and pre- and postoperative course. RESULTS: The average age of the patients was 59 years (18 to 89) with a 55% male/45% female sex distribution. Patients had this procedure as a consequence of malignancy (50%), empyema (30%), spontaneous pneumothorax (10%), bronchiectasis (50%), or heart failure (5%). The average duration of the procedure was 62 minutes (20 to 190), with an average of 861 mL of fluid drainage, and 114 mL of estimated blood loss. The tube thoracostomy was usually removed on the sixth (0 to 13) postprocedure day. This procedure was well tolerated by the patients with the majority of pain management being achieved with patient controlled analgesia (58%). The direct complication rate was 10%, with 2 patients requiring endotracheal intubation. CONCLUSION: This novel thoracoscopic procedure represents an acceptable alternative to the traditional treatment of pleural effusions and empyema with comparable outcome parameters and morbidity. This technique may eventually become the standard of care for the treatment of pleural effusions.  相似文献   
999.
1000.
Investigation of the bypassed stomach in patients with suspected peptic ulcer disease presents a major challenge to bariatric surgeons. Various methods have been suggested for visualization of the duodenum and bypassed stomach. These include endoscopy via percutaneous gastrostomy access, retrograde endoscopy and virtual gastroscopy using CT scan. We present a case of peptic ulcer bleeding diagnosed with the help of conventional CT scan. To the best of our knowledge, this is the second such case reported in the literature and the first in the bariatric population.  相似文献   
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