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991.
Treatment of chronic atrial fibrillation with intraoperative radiofrequency ablation is gaining more acceptance in patients with rheumatic valve disease. This article reports a case of fatal atrio-esophageal fistula after radiofrequency ablation in a patient with rheumatic mitral and aortic valve disease with chronic atrial fibrillation.  相似文献   
992.

Purpose:

The aim of this study was to determine the effects of whole blood, crystalloid, and colloid treatment on histopathologic damage of kidney induced by hemorrhagic shock in rats.

Methods:

Fifty-six male Sprague Dawley rats were divided into 8 groups. The carotid artery was cannulated, and systolic arterial pressure (SAP), diastolic arterial pressure (DAP), heart rate (HR), and rectal temperature (RT) were observed during the procedure. The jugular vein also was cannulated, and the SAP was decreased by aspiration of 75% of blood through the jugular vein in the control (nonresuscitated) and study (resuscitated) groups, whereas blood was not diminished in the sham group. The hemorrhagic shock was permitted to last 45 minutes; then, the study group rats were resuscitated with heparinized shed autologous whole blood (WB), normal saline (NS), Lactated Ringer’s solution (LR), hydroxyethyl starch 6% (HES6), hydroxyethyl starch 10% (HES10), or dextran 40 (D40). Histopathologic evaluation was performed under light and electron microscope.

Results:

The RT, SAP, and DAP decreased, and HR increased significantly in the control and study groups during the shock period compared with those of sham group. After volume resuscitation, these parameters changed to preshock levels. Electron and light microscopic examinations of kidneys showed severe proximal tubular degeneration with moderate glomerular damage in the control group; moderate proximal tubular degeneration with mild glomerular damage in the NS, LR, HES6, and HES10 groups; and mild proximal tubular degeneration with no evidence of glomerular damage in the WB and D-40 groups.

Conclusions:

The characteristic ultrastructural features of hemorrhagic shock appear to be severe tubular degeneration and mild to moderate changes in glomeruli. Resuscitation of hemorrhagic shock with whole blood or dextran 40 solution appears to be most favorable therapy in preventing ultrastructural renal damage in rats.  相似文献   
993.
OBJECTIVE: Atrial fibrillation is a rhythm disorder commonly seen early after coronary artery bypass grafting, and it increases morbidity. METHODS: To investigate the effectiveness of magnesium sulfate in the prophylaxis of atrial fibrillation, we conducted a prospective, randomized, placebo-controlled clinical study on 200 consecutive patients in whom we performed elective and initial coronary artery bypass grafting operations. In each group 50% of patients underwent beating-heart operations. In the treatment group 100 patients (76 men and 24 women; mean age, 57.63 +/- 9.68 years) received 24.34 mEq (3 g) of magnesium sulfate in 100 mL of saline solution that was administered over 2 hours (50 mL/h) preoperatively, perioperatively, and at postoperative days 0, 1, 2, and 3. In the control group 100 patients (74 men and 26 women; mean age, 59.96 +/- 9.29 years) received only 100 mL of saline solution according to the same administration schedule as the treatment group. RESULTS: Atrial fibrillation developed in 15 patients from the treatment group and in 16 patients from the control group. The arrhythmia developed after 37.87 +/- 12.76 and 45.26 +/- 15.27 hours in the treatment and control groups, respectively. Although a significant relationship was found between low magnesium sulfate levels and increased incidence of atrial fibrillation (P <.05), when the incidence of postoperative atrial fibrillation is concerned, no significant difference was found between the 2 groups (P >.05). Also, no significant difference was found between operations with cardiopulmonary bypass and beating-heart operations in terms of atrial fibrillation incidence (P >.05). However, atrial fibrillation extended the duration of hospital stay in both groups (P <.05). CONCLUSION: Our findings indicate that magnesium sulfate infusion alone is not sufficient for the prophylaxis of atrial fibrillation.  相似文献   
994.
BACKGROUND AND OBJECTIVE: Adequate relief of pain after tonsillectomy is a common problem. We compared meperidine and tramadol when given at induction of anaesthesia with respect to their effects on postoperative pain relief and emergence characteristics after adenotonsillectomy in children. METHODS: Fifty children aged 4-7 yr undergoing tonsillectomy were randomly assigned to receive either tramadol 1 mg kg(-1) (n = 25) or meperidine 1 mg kg(-1) (n = 25) before commencement of the surgical procedure. Anaesthesia was induced with propofol (with cis-atracurium for muscle relaxation) and maintained with sevoflurane in oxygen and nitrous oxide. Postoperative pain was scored by a blinded observer using a facial pain scale in the recovery room at 0 (at arrival of the patient in the postoperative care unit) and at 10, 20 and 45 min thereafter. Agitation scores were also assessed by the same observer at 0 min. Heart rate and mean arterial pressure were recorded at regular intervals. The time to recovery to spontaneous respiration and the incidence of postoperative nausea and vomiting were noted. RESULTS: Facial pain scale scores were increased in the tramadol group at 0, 10 and 20 min (P < 0.05). No difference was observed in scores at the 45th min postoperation. Agitation scores were higher in the tramadol group than in the meperidine group. No statistical difference was found between the two groups. Heart rates and mean arterial pressures were similar in both groups. The time to recovery to spontaneous respiration was delayed with meperidine compared with tramadol (P < 0.05). The incidence of nausea and vomiting was not statistically different between groups. CONCLUSIONS: Meperidine was more effective for pain relief and provides better emergence characteristics than tramadol after tonsillectomy in children.  相似文献   
995.
Posterior urethral valves are usually detected during infancy by prenatal sonography. Less is known about presentation and outcome in older patients. We are describing a patient who presented with renal stones and was found incidentally on cystoscopy to have Type I urethral valves.  相似文献   
996.
Kotz and Ganz osteotomies in the treatment of adult acetabular dysplasia   总被引:2,自引:1,他引:1  
In hips with acetabular dysplasia, we performed Kotz osteotomy (group 1) in 22 hips (20 patients; mean age 24.3 years) and Ganz osteotomy (group 2) in 23 hips (22 patients; mean age 23.1 years). Group 1 was followed 83.3 (56-112) months and group 2 40.9 (24-66) months. In group 1, Harris hip score improved from average 74.9 to 86.9, mean center edge (CE) angle from -4.5 degrees to 30.3 degrees, and mean vertical center edge (VCE) angle from 5.3 degrees to 36.2 degrees. In group 2, Harris hip score improved from average 76.6 to 91.1, mean CE angle from -5.9 degrees to 32.0 degrees, and mean VCE angle from 5.0 degrees to 41.3 degrees. Using Pauwels criteria, regression was observed in 12 hips in group 1 and one progressed. In group 2, 15 hips showed regression and three progressed. In patients treated with Ganz osteotomy, the complication rate was higher and the complications more serious than in patients treated with Kotz osteotomy. Most complications were, however, seen among the first ten patients treated with Ganz osteotomy. Although we detected no significant difference between the two groups in terms of clinical and radiological findings, we believe the outcome to be slightly better after a properly performed Ganz osteotomy.  相似文献   
997.
The anterior third ventricle region acquires clinical significance in benign and malignant tumors and cyst formations, of which craniopharyngiomas and gliomas are the most common. The subfrontal approach is one of the most preferred approaches for removing these tumors. In this study, the microsurgical anatomy of 81 Turkish, adult cadaveric hemispheres was examined to provide morphometric data of the region. These measurements from the anterior third ventricle region serve as a guide for neurosurgeons during surgical approach for removing anterior third ventricle tumors.  相似文献   
998.
999.
All kinds of technical faults must be prevented in microvascular anastomosis for successful reconstructive microsurgery. Torsion at the anastomosis site is one of the most basic technical errors. In this study, we investigate the effect of different degrees of microarterial torsion on patency and its physical changes on anastomosis in a rat model. A total of 144 microanastomosis were performed in 72 Sprague-Dawley rats. They were divided into 9 groups. The anastomosis was performed at 0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees, 315 degrees, and 360 degrees of torsion randomly. Patency rates and the narrowest point of the artery after the anastomosis were recorded after 1 hour for each group. In the second stage of the study, the 9 groups were divided into 2 groups for patency rates and histopathological sampling at the second and seventh days postoperatively. The femoral arteries in all groups were all patent at the end of 1 hour. Only 5 microanastomosis were thrombosed (one in the 45 degrees group, one in the 225 degrees group, one in the 270 degrees group, and two in the 315 degrees group) at the second day of exploration. Only two arteries were thrombosed (one in the 45 degrees group and one in the 315 degrees group) at the seventh day of exploration. The patency rate was 96.8% in experimental groups excluding the control group. Different degrees of torsion had no statistically significant effect on the patency rates of microvascular anastomosis. Torsional repair of the femoral artery in the rat has no significant histopathologic changes, but alternately, endothelial integrity was affected by excessive degrees of torsion. Different degrees of torsion at the anastomosis site do not affect patency rates and cross sectional histology of rat femoral arteries. In clinical practice, minor torsion can be tolerated, however, factors affecting patency such as tension, diameter disproportion, and tight closure can affect the final result of anastomosis. We observed that torsional force of the vessel is distributed along the artery to the weakest point.  相似文献   
1000.
Bilgin SS  Topalan M  Ip WY  Chow SP 《Microsurgery》2003,23(4):381-386
Torsion at the microanastomosis site is a basic fault and should be avoided. In this study, we investigate the effects of different degrees of microvenous torsion on patency and its physical changes on anastomoses in a rat model. One hundred anastomoses were performed at different degrees of torsion, using femoral veins of Sprague-Dawley rats. Anastomoses were performed at 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees of torsion randomly. Patency tests immediately, 1 h, and 1 week after the anastomoses were checked, using the refill test. Measurements of external diameter were recorded at three points: one at the anastomosis site, and the others 2 mm proximal and distal to the anastomotic site. Finally, histopathologic and scanning electron microscopy studies were performed. Subsequently, because of the peculiar phenomenon of early recannulation of the thrombosed vessels, 20 vessels were also explored on the first and the third days postoperatively. The data demonstrate that torsion at 180 degrees, compared with 0 degrees, 45 degrees, and 90 degrees, impaired patency significantly (P < 0.005). In the subsequent study of 20 veins that were thrombosed on the first day, all became patent on the third day and remained so. In conclusion, rotation of a microvenous anastomosis begins to affect the patency rate at 90 degrees of torsion, and at 180 degrees has a patency rate of only 25%. However, all become patent again from the third day onwards. Thrombosis of rat femoral veins without chronic obstruction results in rapid lysis of thrombus and transient proliferative changes.  相似文献   
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