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排序方式: 共有9513条查询结果,搜索用时 15 毫秒
61.
Prasad SM Maniar HS Soper NJ Damiano RJ Klingensmith ME 《American journal of surgery》2002,183(6):702-707
BACKGROUND: We hypothesized that laparoscopic tasks performed with ZEUS robotic assistance would be done with greater precision and with a different learning curve than when performed in a standard laparoscopic trainer. METHODS: Participants were divided into the surgically experienced (n = 11) and the surgically naive (n = 17). Two laparoscopic tasks (bead transfer and rope pass) were repeated for five repetitions. RESULTS: For all drills and participants, completion time and error rate decreased across the five repetitions for each platform. Precision averaged 97% for both platforms over all drills. For both groups, completion time for tasks was shorter on the laparoscopic platform. ZEUS allowed for greater consistency in performance. CONCLUSIONS: Compared with performance on a standard laparoscopic trainer, robotic assistance allows for increasing speed and consistency while maintaining precision over multiple repetitions. Understanding how robotics affects learning curves will allow for modifications in the training experience with this new technology. 相似文献
62.
Shicha Kumar Matthew Bramlage Lindsay M. Jacks Jessica I. Goldberg Sujata M. Patil Dilip D. Giri Kimberly J. Van Zee 《Annals of surgical oncology》2010,17(11):2909-2919
Background
Volume of disease in the sentinel lymph node (SLN) is a significant predictor of additional nodal metastasis. This study assesses incidence of residual non-SLN disease in a large cohort of women with minimal SLN metastases and compares three methods of SLN micrometastasis volume measurement to determine which best predicts residual disease on completion axillary lymph node dissection (cALND). 相似文献63.
Charu Mahajan Girija Prasad Rath Parmod Kumar Bithal Hemanshu Prabhakar Rahul Yadav Surya Kumar Dube 《Journal of anesthesia》2010,24(6):845-848
Purpose
Various strategies have been proposed to reduce discomfort of pain after rocuronium injection. These studies have shown pretreatment of drugs such as fentanyl and lidocaine to be effective. In a prospective randomized study, we evaluated whether pretreatment with local warming at injection site using an air-warming device could effectively alleviate pain induced by rocuronium.Methods
Ninety patients undergoing spinal surgeries were randomly divided into two groups: group C (control) and group T (treatment). Patients in group T were subjected to warming at 40°C for 1 min prior to injecting 1 ml (10 mg) of rocuronium at the site of venous access. Patients were then assessed for any discomfort and to quantify their discomfort on a 5-point scale.Results
Age, sex, and weight were comparable between the two groups. Pain on rocuronium administration was reported by 88.9% patient in group C versus 66.7% in group T (p < 0.05). Severe pain was significantly less in group T (35.6% vs. 8.9%).Conclusion
Application of warmth over the vascular access prior to rocuronium administration effectively reduces injection-related pain. 相似文献64.
Bagshaw SM Bellomo R Devarajan P Johnson C Karvellas CJ Kutsiogiannis DJ Mehta R Pannu N Romanovsky A Sheinfeld G Taylor S Zappitelli M Gibney RT 《Journal canadien d'anesthésie》2010,57(11):999-1013
Purpose
This review provides a focused and comprehensive update on established and emerging evidence in acute renal replacement therapy (RRT) for critically ill patients with acute kidney injury (AKI).Principal findings
There have been considerable technological innovations in the methods and techniques for provision of extracorporeal RRT in critical illness. These have greatly expanded our capability to provide both renal and non-renal life-sustaining organ support for critically ill patients. Recent data suggest earlier initiation of RRT in AKI may confer an advantage for survival and renal recovery. Two large trials have recently shown no added benefit to augmented RRT dose delivery in AKI. Observational data have also suggested that fluid accumulation in critically ill patients with AKI is associated with worse clinical outcome. However, several fundamental clinical questions remain to be answered, including issues regarding the time to ideally initiate/discontinue RRT, the role of high-volume hemofiltration or other blood purification techniques in sepsis, and extracorporeal support for combined liver-kidney failure. Extracorporeal support with RRT in sepsis, rhabdomyolysis, and liver failure are discussed, along with strategies for drug dosing and management of RRT in sodium disorders.Conclusions
We anticipate that this field will continue to expand to promote research and innovation, hopefully for the benefit of sick critically ill patients. 相似文献65.
Hirsch R Dent C Pfriem H Allen J Beekman RH Ma Q Dastrala S Bennett M Mitsnefes M Devarajan P 《Pediatric nephrology (Berlin, Germany)》2007,22(12):2089-2095
We hypothesized that neutrophil gelatinase-associated lipocalin (NGAL) is an early predictive biomarker of contrast-induced
nephropathy (CIN). We prospectively enrolled 91 children (age 0–18 years) with congenital heart disease undergoing elective
cardiac catheterization and angiography with contrast administration (CC; Ioversol). Serial urine and plasma samples were
analyzed in a double-blind fashion by NGAL enzyme-linked immunosorbent assay (ELISA). CIN, defined as a 50% increase in serum
creatinine from baseline, was found in 11 subjects (12%), but detection using increase in serum creatinine was only possible
6–24 h after CC. In contrast, significant elevation of NGAL concentrations in urine (135 ± 32 vs. 11.6 ± 2 ng/ml without CIN, p < 0.001) and plasma (151 ± 34 vs. 36 ± 4 without CIN, p < 0.001) were noted within 2 h after CC in those subjects. Using a cutoff value of 100 ng/ml, sensitivity, specificity, and
area under the receiver-operating characteristic (ROC) curve for prediction of CIN were excellent for the 2-h urine NGAL (73%,
100%, and 0.92, respectively) and 2-h plasma NGAL (73%, 100%, and 0.91, respectively). By multivariate analysis, the 2-h NGAL
concentrations in the urine (R
2 = 0.52, p < 0.0001) and plasma (R
2 = 0.72, p < 0.0001) were found to be powerful independent predictors of CIN. Patient demographics and contrast volume were not predictive
of CIN. 相似文献
66.
Amer K. Karam M.D. Meier Hsu M.S. Sujata Patil Ph.D. Michelle Stempel M.S. Tiffany A. Traina M.D. Alice Y. Ho M.D. Hiram S. Cody M.D. Monica Morrow M.D. Mary L. Gemignani M.D. M.P.H. 《American journal of surgery》2011,(6):734-740
Background
Older women are less likely to receive standard of care treatment for breast cancer.Methods
We examined variables that affected the outcome of elderly patients ≥70 years old among 1,470 patients with invasive cancer with positive sentinel lymph nodes (SLNs).Results
Elderly patients were less likely to undergo mastectomy, completion axillary node dissection (ALND), adjuvant chemotherapy, and radiotherapy (RT) following breast-conserving therapy (BCT) compared with patients <70 years old. The 5-year risk of disease progression and cumulative incidence of breast cancer–specific deaths were not significantly different for both groups. On multivariate analysis, hormone receptor–negative status, number of metastatic lymph nodes, high nuclear grade, and tumor size were the factors independently associated with increased risk of disease progression.Conclusions
Tumor factors were the primary determinants of breast cancer outcomes in our cohort. Elderly patients are less likely to receive aggressive surgical interventions and adjuvant therapy because of perceived life expectancy. 相似文献67.
Parikh CR Devarajan P Zappitelli M Sint K Thiessen-Philbrook H Li S Kim RW Koyner JL Coca SG Edelstein CL Shlipak MG Garg AX Krawczeski CD;TRIBE-AKI Consortium 《Journal of the American Society of Nephrology : JASN》2011,22(9):1737-1747
Acute kidney injury (AKI) occurs commonly after pediatric cardiac surgery and associates with poor outcomes. Biomarkers may help the prediction or early identification of AKI, potentially increasing opportunities for therapeutic interventions. Here, we conducted a prospective, multicenter cohort study involving 311 children undergoing surgery for congenital cardiac lesions to evaluate whether early postoperative measures of urine IL-18, urine neutrophil gelatinase-associated lipocalin (NGAL), or plasma NGAL could identify which patients would develop AKI and other adverse outcomes. Urine IL-18 and urine and plasma NGAL levels peaked within 6 hours after surgery. Severe AKI, defined by dialysis or doubling in serum creatinine during hospital stay, occurred in 53 participants at a median of 2 days after surgery. The first postoperative urine IL-18 and urine NGAL levels strongly associated with severe AKI. After multivariable adjustment, the highest quintiles of urine IL-18 and urine NGAL associated with 6.9- and 4.1-fold higher odds of AKI, respectively, compared with the lowest quintiles. Elevated urine IL-18 and urine NGAL levels associated with longer hospital stay, longer intensive care unit stay, and duration of mechanical ventilation. The accuracy of urine IL-18 and urine NGAL for diagnosis of severe AKI was moderate, with areas under the curve of 0.72 and 0.71, respectively. The addition of these urine biomarkers improved risk prediction over clinical models alone as measured by net reclassification improvement and integrated discrimination improvement. In conclusion, urine IL-18 and urine NGAL, but not plasma NGAL, associate with subsequent AKI and poor outcomes among children undergoing cardiac surgery. 相似文献
68.
Background:
The lesion in spondylolysis is a nonunion that follows a fatigue fracture of pars interarticularis. Direct repair of the pars defect is a logical alternative to fusion as it helps to preserve the motion segment and prevents abnormal stresses at the adjacent levels. The purpose of the study is to analyze the clinical and radiological results of direct screw osteosynthesis of the pars defect by the Buck’s method in patients with symptomatic spondylolysis with or without grade 1 spondylolisthesis.Materials and Methods:
Nine patients (six males, three females, mean age 24 years) with symptomatic spondylolysis with or without grade 1 spondylolisthesis and a normal disc in magnetic resonance imaging (MRI), who failed conservative treatment, underwent surgery between January 2000 and April 2009. Of them five patients had bilateral lysis at one level, one had bilateral lysis at three levels and two levels each and two had unilateral lysis at one level. Direct pars repair by the Buck’s method with internal fixation of the defect using 4.5 mm cortical screws and cancellous bone grafting was done. The mean follow-up period was 45 months. MacNab criteria were used to evaluate the postoperative functional outcome. Healing of the pars defect was assessed by plain radiographs and computed tomography (CT) scan.Results:
Spondylolysis was bilateral in seven and unilateral in two patients. Two patients had associated grade 1 spondylolisthesis. The mean operative time was 58 minutes (range 45 – 75 minutes) and blood loss was 98 ml (50 – 140 ml). Although radiological fusion was observed in all patients at a mean follow-up of 45 months (range 9 to 108 months), the functional outcome was excellent in two patients and good in five, with one fair and one poor result. The overall result of the procedure was satisfactory in 78% (7/9) of the patients. The two patients with associated grade 1 spondylolisthesis had fair and poor results. No complications were encountered in the perioperative or postoperative period.Conclusions:
In carefully selected patients, direct repair of the pars defect by the Buck’s technique of internal fixation and bone grafting was a safe and effective alternative to fusion in younger patients with symptomatic spondylolysis, without associated spondylolisthesis, who failed conservative management. 相似文献69.
A 49-year-old male presented with neck pain and deformity following an industrial accident sustained two months back. His neurology was normal except for a minimal weakness in left biceps (grade 4/5). Radiographs, magnetic resonance imaging and computed tomographic scan revealed fracture dislocation of C2-C3 with significant lateral translation of C2 over C3 without disc herniation. In view of unsuccessful closed reduction and absent disc herniation at the level of dislocation, a posterior only reduction, stabilisation and fusion with Iso-C 3D computer navigation-assisted cervical pedicle screw fixation with transverse rod-screw construct was performed. At 6 months followup the patient was completely relieved of his symptoms and was able to return to his previous occupation. The rare case is reported for the management by Iso-C 3D computer navigation assisted cervical pedicle screw fixation and reduction with transverse rod-screw construct at each involved level. 相似文献
70.
Gomez D Farid S Malik HZ Young AL Toogood GJ Lodge JP Prasad KR 《World journal of surgery》2008,32(8):1757-1762
BACKGROUND: This study was designed to evaluate the impact of an elevated preoperative neutrophil-to-lymphocyte ratio (NLR) on outcome after curative resection for hepatocellular carcinoma (HCC). METHODS: Patients undergoing resection for HCC from January 1994 to May 2007 were identified from the hepatobiliary database. Demographics, laboratory analyses, and histopathology data were analyzed. RESULTS: A total of 96 patients were identified with a median age at diagnosis of 65 (range, 15-85) years. The 1-, 3-, and 5-year overall survival rates were 80%, 58%, and 52%, respectively. Although the presence of microvascular invasion, NLR >or=5, and R1 resection margin were adverse predictors of overall survival, there were no independent predictors identified on multivariate analysis. The 1-, 3-, and 5-year disease-free survival rates were 74%, 63%, and 57%, respectively. Preoperative tumor biopsy, NLR >or= 5, multiple liver tumors, microvascular invasion, and R1 resection margin were all predictors of poorer disease-free survival. Multivariate analysis showed that a NLR >or= 5 and R1 resection margin were independent predictors of poorer disease-free survival. The median disease-free survival of those with a NLR >or= 5 was 8 months compared with 18 months for those with a NLR < 5. CONCLUSION: Preoperative NLR >or= 5 was an adverse predictor of disease-free and overall survival. 相似文献