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41.
Die Unfallchirurgie - Es wird über einen 80-jährigen Patienten berichtet, der sich mit einer symptomatischen Coxarthrose der linken Seite in unserer Klinik vorstellte. Das Besondere an...  相似文献   
42.
Primary cardiac paragangliomas are rare extra-adrenal tumors. Though they account for less than 1% of all primary cardiac tumors, they are considerable sources of morbidity and mortality. In this case review, we discuss the challenges associated with the diagnosis and management of cardiac paragangliomas.  相似文献   
43.
Abstract Background and aim: Isolated thoracic aortitis (ITA) is a newly‐defined pathological entity with a still‐unknown etiopathology and with some potential relationship to IgG4‐related systemic disease. We investigated patients on whom the ascending aorta was operated to identify the clinical and histopathological features of ITA and its relationship to IgG4‐related systemic disease. Methods: Two hundred fifty‐one patients underwent replacement of the ascending aorta. Retrospective review of all histological reports was done to identify noninfectious aortitis. Immunohistochemical analysis of resected specimens was performed in all cases. Results: We found 11 (4.4%) patients with noninfectious aortitis aged 52 to 79 years; nine of the patients were female. All patients underwent ascending aorta replacement. The 30‐day mortality was 0. During the follow‐up period (median 12 months) four patients died (two of them because of progression of aortic disease). None of the seven living patients developed any IgG4‐related diseases, and all had normal serum levels of IgG and IgG4. Conclusions: Surgical treatment of ITA has acceptable short‐ and mid‐term results. Because follow‐up serum levels of IgG and IgG4 were normal in survivors, postoperative corticosteroid therapy may not be indicated in patients in the absence of active vasculitis.  相似文献   
44.

Objective

To investigate the safety of surgical performance by residents of different training level performing common general surgical procedures.

Methods

Data were consecutively collected from all patients undergoing general surgical procedures such as laparoscopic cholecystectomy, laparoscopic appendectomy, inguinal, femoral and umbilical hernia repair from 2005 to 2011 at the Department of Surgery of the University Hospital of Zurich, Switzerland. The operating surgeons were grouped into junior residents, senior residents and consultants. The comprehensive complication index (CCI) representing the overall number and severity of all postoperative complications served as primary safety endpoint. A multivariable linear regression analysis was used to analyze differences between groups. Additionally, we focused on the impact of senior residents assisting junior residents on postoperative outcome comparing to consultants.

Results

During the observed time, 2715 patients underwent a general surgical procedure. In 1114 times, a senior resident operated and in 669 procedures junior residents performed the surgery. The overall postoperative morbidity quantified by the CCI was for consultants 5.0 (SD 10.7), for senior residents 3.5 (8.2) and for junior residents 3.6 (8.3). After adjusting for possible confounders, no difference between groups concerning the postoperative complications was detected. There is also no difference in postoperative complications detectable if junior residents were assisted by consultants then if assisted by senior residents.

Discussion

Patient safety is ensured in general surgery when performed by surgical junior residents. Senior residents are able to adopt the role of the teaching surgeon in charge without compromising patients’ safety.
  相似文献   
45.

Background Context

Growing rod constructs are an important contribution for treating patients with early-onset scoliosis. These devices experience high failure rates, including rod fractures.

Purpose

The objective of this study was to identify the failure mechanism of retrieved growing rods, and to identify differences between patients with failed and intact constructs.

Study Design/Setting

Growing rod patients who had implant removal and were previously enrolled in a multicenter registry were eligible for this study.

Patient Sample

Forty dual-rod constructs were retrieved from 36 patients across four centers, and 34 of those constructs met the inclusion criteria. Eighteen constructs failed due to rod fracture. Sixteen intact constructs were removed due to final fusion (n=7), implant exchange (n=5), infection (n=2), or implant prominence (n=2).

Outcome Measures

Analyses of clinical registry data, radiographs, and retrievals were the outcome measures.

Methods

Retrievals were analyzed with microscopic imaging (optical and scanning electron microscopy) for areas of mechanical failure, damage, and corrosion. Failure analyses were conducted on the fracture surfaces to identify failure mechanism(s). Statistical analyses were performed to determine significant differences between the failed and intact groups.

Results

The failed rods fractured due to bending fatigue under flexion motion. Construct configuration and loading dictate high bending stresses at three distinct locations along the construct: (1) mid-construct, (2) adjacent to the tandem connector, or (3) adjacent to the distal anchor foundation. In addition, high torques used to insert set screws may create an initiation point for fatigue. Syndromic scoliosis, prior rod fractures, increase in patient weight, and rigid constructs consisting of tandem connectors and multiple crosslinks were associated with failure.

Conclusion

This is the first study to examine retrieved, failed growing rod implants across multiple centers. Our analysis found that rod fractures are due to bending fatigue, and that stress concentrations play an important role in rod fractures. Recommendations are made on surgical techniques, such as the use of torque-limiting wrenches or not exceeding the prescribed torques. Additional recommendations include frequent rod replacement in select patients during scheduled surgeries.  相似文献   
46.
In osteopetrosis, osteoclast dysfunction can lead to deafness, blindness, bone marrow failure, and death. Hematopoietic cell transplantation (HCT) is currently the only curative treatment, but outcome remains disappointing. Although a rapid progression toward HCT is detrimental to prevent further progress of disease manifestations, 70% of cases lack an HLA‐matched sibling and require alternative stem cell sources. We present two cases of osteopetrosis that successfully received an HCT with haploidentical TcRαβ‐depleted cells from one of the parents. These cases showed no further disease progression, had restoration of functional osteoclasts, and illustrate this approach to enable prompt HCT with ready available parental donors and rapid and sustained hematological, including osteoclast, recovery. © 2016 American Society for Bone and Mineral Research.  相似文献   
47.
The problem of adaptive optimal semiactive control of a structure subjected to a moving load is studied. The control is realised by a change of damping of the structure's supports. The results presented in the previous works of the authors demonstrate that switched optimal controls can be very efficient at reducing the vibration levels of the structure. On the other hand, these controls exhibit a high sensitivity to changes of the speed of the travelling load. The aim of this paper is to develop an algorithm that enables real‐time adaptation of the optimal controls according to both the measured speed of the travelling load and the estimated state of the structure. The control objective is to provide smooth passage for the vehicles and reduce the material stresses on the carrying structures. The designed adaptive algorithm uses reference optimal controls computed for constant speeds and a set of functions describing the sensitivity of the system dynamics to the measured parameters. The convergence of the algorithm, as well as aspects of its implementation, is studied. The performance of the proposed method is validated by means of numerical simulations conducted for different travelling speed scenarios. In the assumed objective functional, the proposed adaptive controller can outperform the reference optimal solutions by over 50%. The practicality of the proposed method should attract the attention of practising engineers.  相似文献   
48.
49.
The Molecular Adsorbent Recirculating System (MARS) represents an attractive artificial liver support system for the treatment of liver insufficiency. However, neither indications for MARS treatment (i.e., after extended liver resection) nor criteria for discontinuation of therapy have been evaluated. Therefore, we analyzed the clinical data of all our surgical patients who received MARS treatment for acute liver failure (n = 7). The aim of the study was to identify prognostic indicators for survival. Four of 174 patients resected for hepatic malignancy at our institution received a total of 13 MARS treatments. Two additional patients were successfully bridged to orthotopic liver transplantation with seven MARS treatments and one patient was MARS supported after liver transplantation of a steatotic graft with three MARS treatments. Five of the seven patients survived and were dismissed an average of 31 days, ranging from 17 to 47 days, after the final MARS treatment. No technical complications or adverse effects were observed during the MARS treatments. Important prognostic factors for hepatic recovery and survival were indocyanin green plasma disappearance rates greater than 5%/min and an increase in clotting factor V levels after each MARS treatment. We conclude that MARS therapy can be an effective treatment of postoperative liver insufficiency in the surgical hepatobiliary unit. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
50.
Multiple trauma is often associated with blunt thoracic injuries. Especially lung contusion can result in respiratory insufficiency and therefore a higher mortality rate. In our prospective study comparing 8 multiple trauma patients with and without associated lung contusion, we found that respiratory function was already significantly disturbed (decrease of paO2/FiO2 and increase of AaDO2, a rise in extravascular lung water (EVLW) both early after trauma and also with a second peak following the 4th day. This group (LK) developed significantly more cases of respiratory distress (ARDS). The disturbance of respiratory function seen initially was interpreted as a consequence of the direct mechanical impact, leading to the formation of interstitial fluid and hematoma. The frequent development of ARDS in the LK-group probably results from a pronounced activation of cellular and humoral mechanisms and therefore an enforced injury of the pulmonary capillary bed. A significant increase of pulmonary infections or the development of sepsis was not seen in the LK-group and is probably not responsible for the higher ARDS-rate in this group.  相似文献   
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