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71.
72.
Nephron preservation has been increasingly prioritized in the treatment of small renal tumors. Radical nephrectomy is now understood as a risk factor for development of chronic kidney disease, which is known to increase the risk of cardiovascular events and all-cause mortality. Indications for nephron-sparing surgery (NSS) have broadened from solitary kidney, bilateral tumors, and hereditary tumor syndromes to essentially all small renal tumors. Laparoscopic NSS has demonstrated excellent cancer control as well as good functional preservation despite the need for warm ischemia. There has been ongoing debate regarding safe parameters for warm ischemia, which are thought to vary with patient factors. Focal ablative therapies have been developed for use in high-risk surgical candidates (eg, radiofrequency ablation, cryoablation) to minimize renal and other treatment-related morbidity. Emphasis on minimally invasive approaches and advances in preventing renal dysfunction and other morbidity after NSS will guide the future of these therapies.  相似文献   
73.

Background  

Treatment of distal tibial intra-articular fractures is challenging due to the difficulties in achieving anatomical reduction of the articular surface and the instability which may occur due to ligamentous and soft tissue injury. The purpose of this study is to present an algorithm in the application of external fixation in the management of intra-articular fractures of the distal tibia either from axial compression or from torsional forces.  相似文献   
74.

Purpose

Hepatectomy remains a complex operation even in experienced hands. The objective of the present study was to describe our experience in liver resections, in the light of liver transplantation, emphasizing the indications for surgery, surgical techniques, complications, and results.

Methods

The medical records of 53 children who underwent liver resection for primary or metastatic hepatic tumors were reviewed. Ultrasonography, computed tomographic (CT) scan, and needle biopsy were the initial methods used to diagnose malignant tumors. After neoadjuvant chemotherapy, tumor resectability was evaluated by another CT scan. Surgery was performed by surgeons competent in liver transplantation. As in liver living donor operation, vascular anomalies were investigated. The main arterial anomalies found were the right hepatic artery emerging from the superior mesenteric artery and left hepatic artery from left gastric artery. Hilar structures were dissected very close to liver parenchyma. The hepatic artery and portal vein were dissected and ligated near their entrance to the liver parenchyma to avoid damaging the hilar vessels of the other lobe. During dissection of the suprahepatic veins, the venous infusion was decreased to reduce central venous pressure and potential bleeding from hepatic veins and the vena cava.

Results

Fifty-three children with hepatic tumors underwent surgical treatment, 47 patients underwent liver resections, and in 6 cases, liver transplantation was performed because the tumor was considered unresectable. There were 31 cases of hepatoblastoma, with a 9.6% mortality rate. Ten children presented with other malignant tumors—3 undifferentiated sarcomas, 2 hepatocellular carcinomas, 2 fibrolamellar hepatocellular carcinomas, a rhabdomyosarcoma, an immature ovarian teratoma, and a single neuroblastoma. These cases had a 50% mortality rate. Six children had benign tumors—4 mesenchymal hamartoma, 1 focal nodular hyperplasia, and a mucinous cystadenoma. All of these children had a favorable outcome. Hepatic resections included 22 right lobectomies, 9 right trisegmentectomies, 8 left lobectomies, 5 left trisegmentectomies, 2 left segmentectomies, and 1 case of monosegment (segment IV) resection. The overall mortality rate was 14.9%, and all deaths were related to recurrence of malignant disease. The mortality rate of hepatoblastoma patients was less than other malignant tumors (P = .04).

Conclusion

The resection of hepatic tumors in children requires expertise in pediatric surgical practice, and many lessons learned from liver transplantation can be applied to hepatectomies. The present series showed no mortality directly related to the surgery and a low complication rate.  相似文献   
75.
Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow.  相似文献   
76.
Bronchopleural fistula after pneumonectomy is a life-threatening complication which is associated with the surgical technique and the experience of the surgeon. We evaluated the incidence of bronchopleural fistula using the posterior membranous flap technique, as originally described by G. Jack in 1965. The surgical technique of bronchial closure proximal to the carina is described and discussed. From 1999 to 2005, 45 consecutive patients underwent pneumonectomy in our hospital using the posterior membranous flap technique for bronchial closure. Twenty-nine patients (64.5%) underwent left pneumonectomy and 16 patients (35.5%) right pneumonectomy. Patients were operated on for non-small cell lung cancer (41 patients - 89%), small cell lung cancer (one patient - 2.2%), mixed and other types of cancer (two patients - 4.4%), and non-neoplastic etiology (one patient - 2.2%). In the follow up of the patients no bronchopleural fistula was identified after pneumonectomy, right or left. Thirty-day mortality was 6.6% (three patients), all because of cardiorespiratory insufficiency. Using the posterior membranous flap technique, we eliminated the two major factors of the occurrence of BPF: (a) the tension in the suture line; and (b) the remaining stump from the resected bronchus. This bronchial closure technique offers a safe method of prevention of bronchopleural fistula.  相似文献   
77.
78.
Background We have previously shown promising activity of hepatic arterial infusion (HAI) oxaliplatin combined with intravenous (IV) 5-fluorouracil (5-FU) and leucovorin (LV) as first-line chemotherapy in patients with colorectal liver metastases (CRLM) (intent-to-treat [ITT] objective response rate [ORR], 64%; secondary resection rate, 18%; overall survival [OS], 27 months). Whether this regimen could be beneficial after systemic chemotherapy failure is unknown. Methods Patients with unresectable CRLM and history of systemic chemotherapy failure were treated bimonthly with HAI oxaliplatin (100 mg/m2 2 hours) combined with IV LV and IV bolus and infusional 5FU (modified LV5FU2 regimen). Results Forty-four consecutive patients (median age 56 years; median number of prior systemic chemotherapy regimens, 2 range 1–5) were included, of whom 43 (98%) had previously received oxaliplatin (n = 34), irinotecan (n = 37), or both (n = 28). Patients received a median of nine cycles of HAI oxaliplatin and IV modified LV5FU2 (range 0–25). Toxicity included grade 3–4 neutropenia (43%), grade 2–3 neuropathy (43%), and grade 3–4 abdominal pain (14%). We observed 24 partial ORs (62%) among the 39 assessable patients (ITT ORR, 55%; 95% CI, 40–69%), including 17, 12, and 12 patients who had failed to respond to prior systemic chemotherapy with FOLFIRI, FOLFOX, or both, respectively. Tumor response allowed further R0 surgical resection (n = 7) or radiofrequency ablation (n = 1) of initially unresectable CRLM in eight patients (18%). Median progression-free survival and OS were 7 and 16 months, respectively. Conclusions HAI oxaliplatin and IV LV5FU2 is feasible, safe, and shows promising activity after systemic chemotherapy failure, allowing surgical resection of initially unresectable CRLM in 18% of patients.  相似文献   
79.
Lung hamartomas are rare benign tumors of the bronchi. Their management consists of bronchoscopic excision or removal through a thoracotomy and bronchotomy whenever there is a large tumor totally obstructing the bronchial lumen. As a lung-sparing procedure is usually the aim, various bronchoplastic techniques have been described, providing a functional lumen of the repaired bronchus. We describe a simple technique that can be safely undertaken to preserve a satisfactory diameter of the bronchus or trachea and prevent a stenosis at the site of repair.  相似文献   
80.
Background: Patients who have undergone gastrectomy for benign ulcer do not develop obesity. Furthermore, morbidly obese patients who undergo biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGBP) and vertical banded gastroplasty (VBG) plus truncal vagotomy, may lose more weight compared with patients who undergo VBG alone. A common characteristic of the above is the reduction of gastric hydrochloric acid secretion. We investigated whether reduction in gastric acid increases dietary- induced thermogenesis because of maldigestion of foods, and this may account for the greater weight loss in the above situations. Materials and Methods: 22 volunteers without symptoms from the upper gastrointestinal tract were studied. Gastric pH was measured and resting energy expenditure (MREE), using indirect calorimetry, was determined before and 8 hours after consumption of a standard meal. Parameters were measured again after 2 months administration of proton pump inhibitors in all volunteers. Results: Although significant reduction of gastric acid secretion occurred (p<0.01), following administration of proton pump inhibitors, the fasting and postprandial MREE remained unchanged (p>0.05). Conclusions: The reduction in gastric acid secretion does not increase the energy requirements for digestion of foods and thus is neither the mechanism responsible for the increased weight loss observed after RYGBP or BPD, nor the explanation for the lean appearance of gastrectomized patients.  相似文献   
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