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101.
BACKGROUND: A colostomy is known to impact negatively on a patient's quality of life (QOL). Concerns include incontinence, rectal discharge, gas, difficulties in returning to work, decreased sexual activity, and travel and leisure challenges. Reports have described QOL outcomes in cancer patients with colostomies and inflammatory bowel syndrome with colostomies, but little has been written regarding a comparison of cancer and non-cancer populations. The purpose of this study was to describe QOL issues of colostomy patients and compare these issues in cancer and non-cancer participants. MATERIALS AND METHODS: A QOL-ostomy questionnaire was mailed to 2455 California members of the United Ostomy Association. RESULTS: Of the 1457 respondents (59%), 599 had a colostomy. Most were results from cancer (517/599), with colorectal cancer being the most common diagnosis. The most common benign diagnoses were inflammatory bowel disease and diverticulitis. Demographics were similar, except for more females in the non-cancer group (76%), and increased length of time with colostomy from the cancer group (mean 135.9 versus 106.4 months, P = 0.03). Common QOL problems included sexual problems, gas, constipation, travel difficulties, and dissatisfaction with appearance. Overall, cancer patients had less difficulty adjusting to their colostomies. CONCLUSIONS: Results confirmed the negative impact of a colostomy on QOL. While patients with cancer had a better overall QOL than those with benign processes, concerns were common to all colostomy patients. These results provide health care practitioners with information useful in discussing QOL concerns during pre-operation treatment decisions and post operative teaching and follow-up care.  相似文献   
102.
103.
OBJECTIVE: This study employed EEG source localisation procedures to study the contribution of motor preparatory and attentional processing to foreperiod activity in an S1-S2 motor priming task. METHODS: Behavioural and high-density event-related potential (ERP) data were recorded in an S1-S2 priming task where participants responded to S2 with a left or right-hand button press. S1 either provided information about response hand (informative) or ambiguous information (uninformative). RESULTS: Responses were significantly faster in informative trials compared with uninformative trials. Dipole source analysis of foreperiod lateralized ERPs revealed sources of motor preparatory activity in the dorsolateral premotor cortex (PMd) in line with previous work. In addition, two spatial attention components (ADAN, LDAP) were identified with generators in the PMd and occipitotemporal visual areas in the middle temporal (MT) region, respectively. Separation of motor-related and attentional PMd source locations was reliable along the rostral-caudal axis. CONCLUSIONS: The presence of attentional components in a motor priming paradigm supports the premotor theory of attention which suggests a close link between attention and motor preparatory processes. Separation of components in the premotor cortex is in accord with a functional division of PMd into rostral (higher-order processing) and caudal (motor-related processing) areas as suggested by imaging work. SIGNIFICANCE: A prime for response preparation is a trigger for separate, but closely linked, attention-related activity in premotor areas.  相似文献   
104.

Background and purpose

Removal of distal cement at femoral implant revision is technically challenging and is associated with complications such as cortical perforations. A technique that can reduce the risks and operating time is to make a small cortical window in the distal femur for enhanced access. We wanted to determine whether the use of long, bridging, cemented femoral stems is necessary to reduce the risk of postoperative periprosthetic fractures after using an anterior cortical bone window.

Methods

66 fresh pig femurs underwent mechanical testing. Steel rods were implanted at 3 locations: (1) at the distal window edge, (2) 15 mm proximally to the cortical window edge, and (3) 15 mm distally. 54 femurs were tested using a 3-point bending setup and 12 femurs were tested using a torsional load setup.

Results

Load to fracture ratio and bending stiffness ratio were similar in the 3 groups, for either the 3-point bending test or the torsional load test.

Interpretation

Our findings suggest that bypass of cortical windows with a revision femoral component may not reduce the risk of periprosthetic fracture.The removal of well-fixed cement is difficult and time consuming. Various surgical techniques and instruments have been developed to facilitate cement removal: extended trochanteric osteotomy (Paprosky et al. 2001), cortical windows (Nelson and Weber 1981), cement removal osteotomes/gauges/reamers (Gray 1992), and ultrasound probes (Goldberg et al. 2007). Iatrogenic femoral host bone loss, inadvertent perforation, and femoral fracture are the main risks associated with the removal of cement (Klein and Rubash 1993).The use of cortical windows, as initially described by Nelson and Weber (1981), reduces the risk of perforation at the revision surgery, while allowing for full weight bearing. The window is typically made near the tip of the implant to facilitate distal cement removal (Moreland et al. 1986, Zweymuller et al. 2005). After removing the cement, the femur is prepared to receive the revision implant. The cortical lid, which has been removed in creating the window, is replaced and secured using a cerclage wire. The femoral prosthesis can then be inserted using standard techniques. Although the risk of perforation is less with the use of a cortical window, the risk of periprosthetic fracture remains. The risk of fracture is related to the size of the window (Panjabi et al. 1985, Larson et al. 1991). Concerns about periprosthetic fractures have led to the recommendation that the cortical window should be bypassed by 2 cortical diameters, by the femoral prosthesis (Dennis et al. 1987, Larson et al. 1991, Klein and Rubash 1993). The rule of two cortical diameters is based on a finite element model by Dennis et al. (1987). There is very little biomechanical data to support this practice. Larson and associates (Larson et al. 1991) published a mechanical study on bypassing cortical defects on canine cadavers. The size of the cortical defect used in their experiment was 50% of the diaphyseal diameter, substantially larger than the window size typically used in clinical practice. The main concern with bypassing the cortical window by 2 cortical diameters is the violation of virgin bone that would otherwise be available for possible future re-revision surgery. Zweymuller et al. (2005) reported on the use of anterior cortical windows during revision hip arthroplasty in 41 cases, where the window was not bypassed by two cortical diameters in 40 of the patients. No periprosthetic fractures were reported at an average follow-up of 7 years. These results, in addition to the present senior author''s clinical experience, raised the question of the need to bypass cortical windows to prevent periprosthetic fractures. We designed a mechanical pig cadaveric study to determine and compare the risk of periprosthetic fracture for bypassed and non-bypassed anterior cortical windows.  相似文献   
105.
BACKGROUND: Feasibility of repeat lengthening has been demonstrated in animals, but in humans, none of the three clinical case reports have achieved enteral autonomy after secondary lengthening with serial transverse enteroplasty (STEP). PATIENTS AND METHODS: Institutional Review Board approved retrospective review of a single center series of repeat intestinal lengthening after prior Bianchi lengthening or STEP. Outcome measures examined include patient survival, weaning from parenteral nutrition, and need for intestinal transplantation. RESULTS: Repeat lengthening with STEP was performed 16 times in 14 patients including 2 adults and 7 male patients after prior Bianchi (n=7) and prior STEP (n=7). Median time after initial lengthening to reSTEP was 12 months (2 months-15 years). Median remnant bowel length before initial lengthening was 35 cm (15-110), before reSTEP was 56.5 cm (27-100) and final length after reSTEP was 90 cm (39-120). Survival is 100% with a median follow-up of 14.5 months (1-65 months). Discontinuation of parenteral nutrition (PN) after reSTEP was achieved in 6 of 14 (43%) patients at a median of 3 months (0.5-13 months) after reSTEP. Intestinal transplant salvage was performed in four patients at 7, 9, 13 months, and 4.6 years, respectively, after reSTEP. All four of those undergoing intestinal transplantation have also subsequently discontinued PN. CONCLUSIONS: Repeat lengthening is technically feasible after either of the available surgical lengthening procedures (Bianchi and STEP). In the stable patient, who is unable to wean from PN, repeat lengthening led to discontinuation of TPN in almost half of these carefully selected patients and does not preclude intestinal transplantation.  相似文献   
106.
R D'Angelo  L S Dean  G C Meister  K E Nelson 《Anesthesia and analgesia》2001,93(6):1560-4, table of contents
We previously found that spinal clonidine prolongs labor analgesia when combined with spinal bupivacaine and sufentanil. We sought to determine whether the addition of spinal neostigmine to these drugs would further enhance labor analgesia. By use of a combined spinal/epidural technique, 36 patients were randomized to receive a hyperbaric spinal injection of bupivacaine 2.5 mg plus clonidine 50 microg and sufentanil 10 microg with or without neostigmine 10 microg. Pain, maternal hemodynamics, fetal heart rate, nausea, pruritus, sedation, motor block, sensory levels to pinprick, and maternal oxygen saturation were assessed at regularly specified intervals after spinal injection until additional analgesia was requested. The duration of spinal analgesia was similar between groups (215 +/- 60 min in the Control group versus 205 +/- 62 min in the Neostigmine group). Likewise, pain scores, the duration of labor, Apgar scores, and side effects were similar between groups except that patients administered neostigmine experienced significantly more nausea and vomiting (53% vs 7%, P = 0.01). We conclude that spinal neostigmine 10 microg produces severe nausea and does not potentiate the duration of spinal analgesia in laboring women from spinal bupivacaine, clonidine, and sufentanil. IMPLICATIONS: Spinal neostigmine 10 microg as an adjunct to spinal bupivacaine, clonidine, and sufentanil produces severe nausea and fails to potentiate analgesia in laboring women.  相似文献   
107.
Hemorrhagic shock (HS) and resuscitation can be seen as a global body ischemia-reperfusion (I/R) injury characterized by neutrophil infiltration and organ damage. Liver dysfunction occurs early after HS. Adhesion molecules are needed for the first steps ofneutrophil migration. Thus, the purpose of this study was to investigate the role of L-selectin in the liver after uncontrolled HS and resuscitation. Forty-eight Sprague Dawley rats were subjected to uncontrolled HS and resuscitation. Animals were divided into three groups: sham, uncontrolled HS and resuscitation, and uncontrolled HS and resuscitation with anti-L-selectin treatment. At 6 we evaluated liver injury tests, liver tissue myeloperoxidase (MPO), and liver histology. Survival was followed for 3 days and compared between groups. Statistical analysis included Fisher's exact test and one-way analysis of variance. Survival significantly increased from 30% in the control group to 60% in the treated group (p < .05). Hepatocellular and structural injury as well as neutrophil infiltration was significantly decreased in treated animals (p < .05). Thus, blockade of L-selectin resulted in decreased hepatocellular injury and increased survival in our model of uncontrolled HS. Selectins may be important therapeutic targets for blockade in the treatment of HS.  相似文献   
108.
Various patterns of ankle fractures that are not accounted for by common classification systems have been the subject of case reports. The first difficulty with these variant patterns is recognizing all associated pathology, followed by the successful application of stable fixation. The purpose of this study was to describe the common morphologic features and ligamentous injuries of a unique variant fracture pattern, as well as the surgical treatment technique and the short-term functional and radiographic outcomes. Of 121 consecutive unstable ankle fractures over a 2-year period, 7 patients were found to have a similar constellation of injuries around the ankle. A vertical shear fracture of the posteromedial tibial rim was the main feature. Six of the 7 also had a fracture of the posterior malleolus. On magnetic resonance imaging, the deltoid and posterior tibiofibular ligaments were intact in all cases. Fractures were treated with open anatomic reduction of the posteromedial and posterior fragments with antiglide plate fixation. All fractures healed at 2 months without loss of reduction, fixation failure, or surgical complications. The average American Academy of Orthopaedic Surgeons lower extremity score was 79 at an average of 8 months' follow-up. The common radiographic and morphologic features associated with this posteromedial fracture indicate that it likely occurs through a common mechanism that involves hyperplantarflexion. The characteristics of this fracture pattern have not been fully described previously, but this ankle fracture variant may occur in up to 6% of cases. Unstable ankle fractures should be evaluated carefully for evidence of posteromedial involvement so appropriate treatment may proceed.  相似文献   
109.
The vast majority of tibial plateau fractures heal uneventfully, and no case series on intraarticular tibial plateau nonunions exists. The purpose of the present study was to evaluate the radiographic and clinical outcome of these nonunions following surgical treatment in a single surgeon series. Five patients with tibial plateau nonunions were treated at our institution using a specific treatment protocol consisting of open reduction and debridement, deformity correction, internal fixation including lag screws, bone graft augmentation, and selective knee joint arthrolysis. Patient outcomes were assessed using radiographs and the Knee Society questionnaire scores. Following surgical treatment of the nonunion, all healed at an average of 12.8 weeks, and average follow-up was 44 months. Preoperative coronal plane deformity was corrected in all patients. The final knee motion arc averaged 120 degrees postoperatively. Both the pain and function subscales of the Knee Society Rating scale improved significantly. Four of the five returned to their normal pre-injury activities, but two patients required total knee arthroplasty which was performed successfully after healing of the nonunion. With meticulous surgical technique and a standard protocol, healing may be reliably achieved. Arthrosis occurs frequently, and may occur primarily at the time of injury or from chronic alteration of intraarticular contact forces secondary to development of a nonunion.  相似文献   
110.
BACKGROUND: Preemptive kidney transplantation (prior to the institution of dialysis) avoids the morbidity and mortality of dialysis; however, detailed studies of high-risk patients are lacking. The aim of the current study was to compare recent outcomes of preemptive (P) versus nonpreemptive (NP) living donor kidney transplantation with an emphasis on high-risk recipients. METHODS: We retrospectively analyzed 438 sequential solitary living donor kidney transplants at our institution between January 2000 and December 2002. In all, 44% were preemptive. NP recipients were dialyzed for 21+/-36 months (range 1-312 months). RESULTS: Overall, three-year patient survival was similar in the NP and P groups. When stratified by diabetes and age >65 years, P and NP recipients again showed similar survival. Death-censored three-year graft survival was better in the P group (97% vs. 90%, P=0.01), but was not significant by multivariate analysis. Delayed graft function was more frequent in NP vs. P (10% vs. 4%; P=0.01), but other early complications were similar including: acute rejection, 16% vs. 11% (P=0.11); primary nonfunction, 3% vs. 2% (P=0.38); and wound complications, 19% vs. 17% (P=0.54). Glomerular filtration rate at three years was similar in the two groups (53+/-23 preemptive vs. 52+/-20 ml/min nonpreemptive; P=0.37). CONCLUSION: With prompt referral and workup, preemptive kidney transplantation can be performed successfully in a large percentage of renal allograft recipients. Preemptive transplantation avoids unnecessary dialysis and should be emphasized as initial therapy for many patients with end-stage renal disease.  相似文献   
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