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41.

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   
42.
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   
43.
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   
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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   
46.
AIMS: To determine if the abdominal leak point pressure (ALPP) correlates with objective incontinence severity in patients suffering from post-prostatectomy stress incontinence. METHODS: Twenty-nine men were evaluated for urinary incontinence after radical prostatectomy with videourodynamics and a 24-hr pad test. ALPP was determined with and without a 7-French urodynamics catheter and the lowest value was accepted. Six patients with urgency incontinence associated with detrusor overactivity or decreased bladder compliance were excluded leaving 23 patients for analysis. The relationship between the variables of ALPP, 24-hr pad weight, age and time from prostatectomy were examined with Pearson correlation. RESULTS: The mean age was 66.4 years (SD +/- 7.9, range: 45-81) and the median time from radical prostatectomy was 23 months (IQR = 14-64, range: 9-204). The mean ALPP was 92.8 cm H(2)O (SD +/- 42.4 cm H(2)O) and the mean pad weight was 279.1 g (SD +/- 238.3 g). There was only a weak inverse correlation between ALPP and 24-hr pad weight which was not statistically significant (r = - 0.191, P = 0.38). Age and time from prostatectomy did not significantly correlate with ALPP (r = - 0.122, P = 0.58 and r = - 0.23, P = 0.29, respectively). CONCLUSIONS: ALPP did not correlate significantly with the 24-hr pad test in patients with post-prostatectomy stress incontinence. This suggests that in this patient subset, the ALPP is a relatively poor predictor of incontinence severity and, therefore, has limited clinical value in the urodynamic evaluation of post-prostatectomy incontinence. The urodynamic assessment of these patients should focus on the presence or absence of stress incontinence and on the presence of associated bladder dysfunction.  相似文献   
47.
The objective of this study was to investigate the contribution of cystic fibrosis transmembrane conductance regulator (CFTR) to human infertility and to define screening and counselling procedures for couples asking for assisted reproduction treatment. Extended CFTR mutation screening was performed in 310 infertile men (25 with congenital absence of the vas deferens (CAVD), 116 with non-CAVD azoospermia, 169 with severe oligospermia), 70 female partners and 96 healthy controls. CFTR mutations were detected in the majority (68%) of CAVD patients and in significant proportions in azoospermic (31%) and oligospermic (22%) men. Carrier frequency among partners of infertile men was 16/70, exceeding that of controls (6/96) significantly (P = 0.0005). Thus, in 23% of infertile couples both partners were carriers, increasing the risk for their offspring to inherit two mutations to 25% or 50%. This study emphasizes the necessity to offer extended CFTR mutation screening and counselling not only to patients with CAVD but also to azoospermic and oligozoospermic men and their partners before undergoing assisted reproduction techniques. The identification of rare and/or mild mutations will not be a reason to abstain from parenthood, but will allow adequate treatment in children at risk for atypical or mild cystic fibrosis as soon as they develop any symptoms.  相似文献   
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Event-related potential responses to oddball stimuli, including the P300 component, have been proposed as a diagnostic tool for discerning psychiatric or higher-level neural disorders from malingering, for instance in cases of unexplained visual loss. For clinical use, short recording durations and easy statistical assessment are highly desirable. With this aim, we investigated the feasibility of recording oddball responses in a fast steady-state regime. We used gratings with two possible orientations in a rapid oddball paradigm with an inter-stimulus interval of 214 ms. Six consecutive presentations of one stimulus type (frequent) were followed by a single presentation of the other (infrequent) stimulus type. Subjects were attending to the rare stimulus type. The electroencephalographic recordings were analyzed in the frequency domain. All subjects produced significant harmonic responses related to the processing of the rare stimulus, demonstrating the feasibility of the technique, with the potential of reducing recording times substantially compared to conventional slow stimulation. We furthermore found that the regularity of the occurrence of infrequent stimuli, which is necessary for frequency-domain analysis, does not per se reduce the P300 responses, as would have been expected in the framework of some hypotheses regarding the role of the P300.  相似文献   
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