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71.
Hanna MH  Elliott KM  Fung M 《Anesthesiology》2005,102(4):815-821
BACKGROUND: Morphine-6-glucuronide (M6G) has promising preclinical characteristics and encouraging pharmacokinetic features for acute nociceptive pain. Early studies have produced a good safety profile when compared to morphine sulfate, although in surrogate pain models studies, a mixed picture emerged. A study to evaluate the efficacy and safety profile in a clinical setting was designed. METHODS: The authors conducted a double-blind, randomized, dose-finding study of patients scheduled to undergo major joint replacement. One hundred patients of both sexes were included, with 50 patients in each group. A loading dose of 10 mg of study medication was given intravenously at induction of anesthesia, and two further doses were allowed during surgery if required. Bolus doses via a patient-controlled analgesia system were given subcutaneously at 2 mg/dose and set at a 10-min lockout. Assessments of pain intensity and relief were recorded during the 24-h period. RESULTS: There were no statistically significant differences between the treatments for 24-h mean pain intensity. However, pain intensity was significantly higher in the M6G group than in the morphine group at 30 min and 1 h. There was no statistical difference in 24-h mean pain relief or retrospective pain scores at any time point during the 24-h period. The severity of sedation was significantly greater in the morphine group than in the M6G group at 30 min, 1 h, 2 h, and 24 h. Respiratory depression was greater in the morphine group than in the M6G group, and more patients in the morphine group withdrew from the study because of respiratory depression. CONCLUSIONS: Overall, M6G has an analgesic effect similar to that of morphine over the first 24 h postoperatively. However, M6G may be slower onset initially than morphine; therefore, a larger initial dose may be required.  相似文献   
72.

Background

Synthetic mesh (SM) has been used in the laparoscopic repair of hiatus hernia but remains controversial due to reports of complications, most notably esophageal erosion. Biological mesh (BM) has been proposed as an alternative to mitigate this risk. The aim of this study is to establish the incidence of complications, recurrence and revision surgery in patients following suture (SR), SM or BM repair and undertake a survey of surgeons to establish a perspective of current practice.

Methods

An electronic search of EMBASE, MEDLINE and Cochrane database was performed. Pooled odds ratios (PORs) were calculated for discrete variables. To survey current practice an online questionnaire was sent to emails registered to the European Association for Endoscopic Surgery.

Results

Nine studies were included, comprising 676 patients (310 with SR, 214 with SM and 152 with BM). There was no significant difference in the incidence of complications with mesh compared to SR (P = 0.993). Mesh significantly reduced overall recurrence rates compared to SR [14.5 vs. 24.5 %; POR = 0.36 (95 % CI 0.17–0.77); P = 0.009]. Overall recurrence rates were reduced in the SM compared to BM groups (12.6 vs. 17.1 %), and similarly compared to the SR group, the POR for recurrence was lower in the SM group than the BM group [0.30 (95 % CI 0.12–0.73); P = 0.008 vs. 0.69 (95 % CI 0.26–1.83); P = 0.457]. Regarding surgical technique 503 survey responses were included. Mesh reinforcement of the crura was undertaken by 67 % of surgeons in all or selected cases with 67 % of these preferring synthetic mesh to absorbable mesh. One-fifth of the respondents had encountered mesh erosion in their career.

Conclusions

Both SM and BM reduce rates of recurrence compared to SR, with SM proving most effective. Surgical practice is varied, and there remains insufficient evidence regarding the optimum technique for the repair of hiatal hernia.
  相似文献   
73.
74.
Arthroplasty for intertrochanteric fractures in elderly patients may allow early weightbearing and avoid fixation failure. Clinical results are reviewed in a consecutive group of acute arthroplasties (5 hemiarthroplasties and 29 total hip arthroplasties) performed via the anterolateral approach for intertrochanteric fractures. Age averaged 80.2 years. Follow-up averaged 35 months for living patients. Twenty-six patients died during follow-up. Time to death averaged 3.5 years. Five hips, all total hip arthroplasties, required subsequent surgeries: four for dislocation and one revised for sepsis. Acute intertrochanteric fractures are associated with high early mortality. In this series, a 15% complication rate and high mortality rate at 12 years was associated with acute arthroplasty. Dislocation is higher than in primary total hip arthroplasty utilizing the same surgical approach. The results do not support routine use of arthroplasty in treatment of intertrochanteric hip fractures in the elderly.  相似文献   
75.
Background  A premise of this study was that different psychological processes would predict the initiation and maintenance of weight loss after surgery for morbid obesity. Our aim was to examine whether more favorable preoperative expectations of psychosocial outcomes predict weight loss in the first year after laparoscopic adjustable gastric banding (LAGB) and whether postoperative satisfaction with these outcomes predicts weight maintenance in the second year after the operation. Methods  Six months before and 1 year after surgery, the “Obesity Psychosocial State Questionnaire” was filled out by 91 patients (77 female, 14 male, mean age 45 ± 9 years, mean preoperative body mass index 47 ± 6 kg/m2). We evaluated the preoperative outcome expectations and the postoperative satisfaction for the seven domains of psychosocial and physical functioning of this questionnaire, as well as the correlations between these scores and both weight loss and weight maintenance. Results  Patients showed high satisfaction with psychosocial outcomes after LAGB in all seven domains (p < 0.001), even though the improvement was less than expected in five of the domains (p ≤ 0.01). While weight loss 1 year after the operation was related to satisfaction with psychosocial outcomes (p ≤ 0.05), preoperative expectations were not related to weight loss in the first year after surgery, and satisfaction with the outcomes was not related to weight maintenance in the second year after surgery. Conclusion  Our study suggests that surgically induced effects of weight loss and weight maintenance are achieved independently of the patient’s preoperative expectations of and postoperative satisfaction with the psychosocial outcomes.  相似文献   
76.

Purpose

To examine the relationship between tibiofemoral and patellofemoral joint articular cartilage and subchondral bone in the medial and gait biomechanics following partial medial meniscectomy.

Methods

For this cross-sectional study, 122 patients aged 30–55 years, without evidence of knee osteoarthritis at arthroscopic partial medial meniscectomy, underwent gait analysis and MRI on the operated knee once for each sub-cohort of 3 months, 2 years, or 4 years post-surgery. Cartilage volume, cartilage defects, and bone size were assessed from the MRI using validated methods. The 1st peak in the knee adduction moment, knee adduction moment impulse, 1st peak in the knee flexion moment, knee extension range of motion, and the heel strike transient from the vertical ground reaction force trace were identified from the gait data.

Results

Increased knee stance phase range of motion was associated with decreased patella cartilage volume (B = ?17.9 (95 % CI ?35.4, ?0.4) p = 0.045) while knee adduction moment impulse was associated with increased medial tibial plateau area (B = 7.7 (95 % CI 0.9, 13.3) p = 0.025). A number of other variables approached significance.

Conclusions

Knee joint biomechanics exhibited by persons who had undergone arthroscopic partial meniscectomy gait may go some way to explaining the morphological degeneration observed at the patellofemoral and tibiofemoral compartments of the knee as patients progress from surgery.

Level of evidence

III.  相似文献   
77.
Sensation seeking is the tendency to seek out new and thrilling experiences and to take risks for the sake of such experiences. A single‐nucleotide polymorphism, ?521 C/T (rs1800955) in the promoter region of the dopamine‐4‐receptor gene (DRD4), is associated with approach‐related traits including novelty seeking and extraversion, in some, but not all studies. To our knowledge, no studies have been conducted on the genetics of risk‐taking behavior in sports. Using a joint‐analysis approach, we measured sensation seeking in two cohorts of experienced male and female skiers and snowboarders (n = 503) using a sports‐specific tool developed for this study, the Contextual Sensation Seeking Questionnaire for Skiing and Snowboarding (CSSQ‐S), and a more general trait measure, the Zuckerman–Kuhlman Personality Questionnaire impulsive sensation‐seeking subscale. We detected, and then replicated a significant association between the DRD4 ?521CC genotype and sports‐specific sensation seeking as measured using the CSSQ‐S (P < 0.001). These data suggest that the DRD4 ?521 C/T polymorphism contributes to a “risk‐taking phenotype” in skiers and snowboarders, but the variant was not associated with impulsive sensation seeking (P = 0.9).  相似文献   
78.
Gallium imaging offers many practical advantages over indium-111-labeled leukocyte imaging, and calculating quantitative ratios in addition to performing the routine bone-gallium images allows accurate and easy evaluation of patients with suspected osteomyelitis. To add objectivity and improve the accuracy and confidence in diagnosis of osteomyelitis, quantitative comparison of abnormalities seen on bone scans and gallium scans was performed. One hundred and ten adult patients with 126 sites of suspected osteomyelitis were evaluated and categorized by gallium-to-bone ratios, gallium-tobackground ratios, and spatial incongruency of gallium and bone activity. Combined evaluation using these criteria gave a 70% sensitivity and 93% specificity for the diagnosis of osteomyelitis.  相似文献   
79.
BACKGROUND: The type of stent used for the management of patients with malignant dysphagia is chosen according to subjective physician's preference. There is no recent study available to provide updated evidence on early outcomes related to the use of different types of stents. METHODS: A literature search was performed using Embase, MEDLINE, Cochrane Library, and Google Scholar databases for comparative studies assessing different types of stents. The primary end point was stent-related mortality; secondary end points included: stent-related morbidity, successful palliation of dysphagia, and 30-day mortality. A random-effects model was used and heterogeneity was assessed. RESULTS: Twelve studies that included 911 patients compared metallic (46.54%) and plastic stents (53.45%), and eight studies that included 564 patients compared covered (43.26%) and uncovered metal stents (56.73%). Meta-analysis of randomized, controlled trials showed that metallic stents were associated with significantly reduced stent-related mortality (1.7% vs. 11.1% for the plastic group, odds ratio (OR), 0.2; 95% confidence interval (CI), 0.06-0.74; P = 0.02), morbidity in the form of reduced esophageal perforation (1.4% vs. 9.4% for plastic stent, OR, 0.27; 95% CI, 0.08-0.89; P = 0.03), and stent migration, yet increased rate of tumor in-growth (13% vs. 1.6% for plastic stents, OR, 4.84; 95% CI, 0.99-23.76; P = 0.05). Covered metallic stents had significantly less tumor in-growth than the uncovered and an increased migration rate. There was no significant difference between metallic and plastic stents in terms of any other stent-related morbidity and 30-day mortality. CONCLUSION: Self-expanding metallic stents are superior to plastic stents in terms of stent insertion-related mortality, morbidity, and quality of palliation. The uncovered variety is disadvantaged by high rate of tumor in-growth; adequately designed randomized, controlled trials need to examine outcomes and cost-effectiveness of covered versus uncovered metallic stents.  相似文献   
80.
Suture technique for valve replacement surgery has often focused on decreasing the soft tissue injury that leads to pseudoaneurysm formation and associated latent infection. There is universal recognition that precise suture placement is essential for avoiding adverse sequelae while allowing flexibility during the implantation of the prosthesis. The use of a continuous chain of linked horizontal mattress sutures (NextStitch) has allowed maximal precision in the approximation of sutures within the valve annulus. The product was used in a series of consecutive mitral and aortic valve replacements, and typical echocardiographic images from each type of implantation are presented. Postoperative echocardiography images revealed that no perivalvular leaks occurred and that NextStitch did not obscure detailed interrogation or assessment of the valve prosthesis.  相似文献   
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