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991.
Ring ME 《The New York state dental journal》2003,69(1):31-34
In the earlier days of dentistry, patients suffered terrible tortures and accidents at the hands of untrained individuals who attempted to extract the sufferer's teeth. Even as dental knowledge and skill advanced, there were still numerous untoward occurrences during extractions, some of them resulting in the death of the patient. The article ends with the recounting of a near-fatal case that was in no way the dentist's fault and could not have been prevented. 相似文献
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995.
Zacherl J Stangl M Feussner H Shibakita M Bock S Erhardt W Siewert JR 《The Journal of surgical research》2002,103(2):268-271
BACKGROUND: Laparoscopic donor nephrectomy decreases disincentives to donation frequently associated with the disadvantages of open surgery. However, concerns have been raised regarding graft quality, since the incidence of delayed graft function is higher when compared with open procedures. This may be caused by amelioration of kidney perfusion due to the elevated intraabdominal pressure and to a mechanically induced renal angiospasm during donation. This study was addressed to reveal whether the renal periarterial application of papaverine is able to enhance renal blood flow during laparoscopic nephrectomy. MATERIALS AND METHODS: Twelve male piglets underwent left laparoscopic donor nephrectomy after endoscopic occlusion of the right renal vessels and ureter. Urine output and creatinine clearance were determined as indicators of renal blood flow. In the treatment group (n = 6) papaverine hydrochloride was administered to the tissue surrounding the renal artery prior to preparation of the vessels and results were compared with those of controls (n = 6). Free sodium excretion was measured to preclude prerenal failure. RESULTS: In the control group the mean urine output was 0.015 ml/min/kg and the mean creatinine clearance was 0.95 ml/min/kg. In pigs treated with papaverine the mean urine output was 0.052 ml/min/kg and the mean creatinine clearance was 2.22 ml/min/kg. The differences were significant (urine output, P = 0.02; creatinine clearance, P = 0.038). CONCLUSIONS: Papaverine improves renal function during laparoscopic kidney harvest when applied in the vicinity of the renal artery prior to vascular preparation. 相似文献
996.
Johannes N Hoffmann Sonja Steinhagen Christina Kast Heinz P Scheuber Marianne Jochum Cornelia Gippner-Steppert Dietrich Inthorn Friedrich W Schildberg Dirk Nolte 《The Journal of surgical research》2002,102(2):119-125
BACKGROUND: This study describes a modified catheterization technique with subcutaneously implanted port catheters to be inserted in a retrograde manner across the aortic valve into the left heart ventricle through the right carotid artery to measure organ perfusion. MATERIALS AND METHODS: The specially designed arterial port catheters were implanted in New Zealand rabbits (n = 11, 3.7 +/- 0.1 kg [mean +/- SEM]) under iv anesthesia (medetomidine/ketamine) and single-shot perioperative antibiotic therapy. Hemodynamics were registered continuously during the operation via an ear artery catheter. RESULTS: Implantation of ports was performed in all animals (11/11) without major complications (mean operation time: 70 +/- 3 min). We did not observe catheter-associated arrhythmia, fall in mean arterial pressure (MAP before and post OP: 70 +/- 2 and 68 +/- 2 Torr, respectively), or change in arterial oxygen saturation (SaO2 before and post OP: 89 +/- 3 and 95 +/- 2%, respectively). With a specifically modified microsurgical insertion technique, cerebral blood supply was effectively preserved as evidenced from postmortem histological examinations, cerebral blood flow determination with fluorescent microspheres, and measurement of S-100b protein serum concentrations, a specific marker of neuronal damage. The positioning of the catheter tip in the left ventricle was found to be correct in 10/11 animals. CONCLUSIONS: Repeated and atraumatic microsphere injections into the left ventricle have become feasible by transcutaneous puncture of subcutaneous port systems over several weeks under light sedation. Hence, this new approach (i) avoids the necessity of repeated intracardiac injections and port insertions via thoracotomy, thus reducing the perioperative stress for the animals, and (ii) allows for the first time minimally invasive repetitive and chronic measurements of regional organ blood flow under various experimental settings. 相似文献
997.
998.
Integrated fellowship in vascular surgery and intervention radiology: a new paradigm in vascular training 下载免费PDF全文
Messina LM Schneider DB Chuter TA Reilly LM Kerlan RK LaBerge JM Wilson MW Ring EJ Gordon RL 《Annals of surgery》2002,236(4):408-415
OBJECTIVE: To evaluate an integrated fellowship in vascular surgery and interventional radiology initiated to train vascular surgeons in endovascular techniques and to train radiology fellows in clinical aspects of vascular diseases. SUMMARY BACKGROUND DATA: The rapid evolution of endovascular techniques for the treatment of vascular diseases requires that vascular surgeons develop proficiency in these techniques and that interventional radiologists develop proficiency in the clinical evaluation and management of patients who are best treated with endovascular techniques. In response to this need the authors initiated an integrated fellowship in vascular surgery and interventional radiology and now report their interim results. METHODS: Since 1999 vascular fellows and radiology fellows performed an identical year-long fellowship in interventional radiology. During the fellowship, vascular surgery and radiology fellows perform both vascular and nonvascular interventional procedures. Both vascular surgery and radiology-based fellows spend one quarter of the year on the vascular service performing endovascular aortic aneurysm repairs and acquiring clinical experience in the vascular surgery inpatient and outpatient services. Vascular surgery fellows then complete an additional year-long fellowship in vascular surgery. To evaluate the type and number of interventional radiology procedures, the authors analyzed records of cases performed by all interventional radiology and vascular surgery fellows from a prospectively maintained database. The attitudes of vascular surgery and interventional radiology faculty and fellows toward the integrated fellowship were surveyed using a formal questionnaire. RESULTS: During the fellowship each fellow performed an average of 1,201 procedures, including 808 vascular procedures (236 diagnostic angiograms, 70 arterial interventions, 59 diagnostic venograms, 475 venous interventions, and 43 hemodialysis graft interventions) and 393 nonvascular procedures. On average fellows performed 20 endovascular aortic aneurysm repairs per year. There was no significant difference between the vascular surgery and radiology fellows in either the spectrum or number of cases performed. Eighty-eight percent (23/26) of the questionnaires were completed and returned. Both interventional radiologists and vascular surgeons strongly supported the integrated fellowship model and favored continuation of the integrated program. Vascular surgery and interventional radiology faculty members wanted additional training in clinical vascular surgery for the radiology-based fellows. With the exception of the radiology fellows there was uniform agreement that vascular surgery fellows benefit from training in nonvascular aspects of interventional radiology. CONCLUSIONS: Integration of vascular surgery and interventional radiology fellowships is feasible and is mutually beneficial to both disciplines. Furthermore, the integrated fellowship provides exceptional training for vascular surgery and interventional radiology fellows in all catheter-based techniques that far exceeds the minimum requirements for credentialing suggested by various professional societies. There is a clear need for cooperation and active involvement on the parts of the American Board of Radiology and the American Board of Surgery and its Vascular Board to create hybrid training programs that meet mutually agreed-on criteria that document sufficient acquisition of both the cognitive and technical skills required to manage patients undergoing endovascular procedures safely and effectively. 相似文献
999.
Factors influencing intensive care unit length of stay after surgery for acute aortic dissection type A 总被引:4,自引:0,他引:4
Hoefer D Ruttmann E Riha M Schobersberger W Mayr A Laufer G Bonatti J 《The Annals of thoracic surgery》2002,73(3):714-8; discussion 718-9
BACKGROUND: Operative mortality after acute aortic dissection type A is still high, and prolonged stay at the intensive care unit is common. Little has been documented about factors influencing the intensive care unit length of stay. The aim of this study was to determine such variables. METHODS: During a 10-year period, 67 patients (47 male, 20 female) were operated on for acute aortic dissection type A. In 42 patients (63%), an ascending aortic replacement was performed, 23 patients (34%) underwent a Bentall procedure, and 2 patients (3%) received a valve-sparing David type of operation. In 14 of these cases (20%), an additional partial or total arch replacement was performed. RESULTS: Hospital mortality was 9 of 67 (14%). Median postoperative intensive care unit length of stay was 5 days (range, 1 to 72 days). Intensive care unit stay was in univariate analysis significantly influenced by the following factors: age (p = 0.008), body mass index (p = 0.039), cardiopulmonary bypass time (p = 0.018), aortic cross-clamp time (p = 0.031), postoperative low cardiac output syndrome (p < 0.001), and postoperative lactate levels (p = 0.01). By multivariate analysis, age (p = 0.012), cardiopulmonary bypass time (p = 0.037), and the presence of a postoperative low cardiac output syndrome (p < 0.001) significantly influenced intensive care unit stay. CONCLUSIONS: Stay in the intensive care unit after operation for acute aortic dissection type A seems to be determined by age, cardiopulmonary bypass time, and the postoperative presence of a low cardiac output syndrome. 相似文献
1000.
Utzig MJ Warzelhan J Wertzel H Berwanger I Hasse J 《The Annals of thoracic surgery》2002,74(6):480-1952
BACKGROUND: Wegener's granulomatosis (WG) is defined as granulomatous vasculitis affecting small and medium-sized arteries and veins. Histologically, inflammatory changes with infiltration of the endothelium, fibrinoid necrosis, and formation of necrotizing granulomas are found. Pulmonary involvement is one of the cardinal features of WG and occurs in 85% of patients during the course of disease. Surgery is often required for both diagnosis and therapy. METHODS: Fifteen consecutive patients are presented to illustrate the spectrum of surgical interventions in WG. RESULTS: In 8 patients open lung biopsy, wedge resection, or segmental resection for hitherto undiagnosed infiltrate revealed WG. Eight patients presented with tracheal stenosis and all 8 underwent repetitive tracheoscopic dilation. Five patients presented with subglottic stenosis without any signs of pulmonary manifestation. All patients underwent tracheoscopic dilation, 3 in conjunction with glucocorticoid injection therapy. After multiple dilations, 1 patient still had destructing ulcerative tracheitis in which total stenting maintained airway patency. One patient received subglottic tracheal resection prior to multiple dilations; another patient, because of expiratory tracheal collapse, underwent stabilization of the membranous part of the trachea and the large bronchi with a polytetrafluoroethylene implant. CONCLUSIONS: Surgical lung biopsy in numerous patients established the final diagnosis. Thoracic surgery including bronchologic measures such as bouginage and stenting, however, also has a place in the long-term management of WG. 相似文献