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81.
Aliasgar V. Moiyadi Prakash M. Shetty Abhishek Mahajan Amar Udare Epari Sridhar 《Acta neurochirurgica》2013,155(12):2217-2225
Background
Intraoperative imaging is increasingly being used in resection of brain tumors. Navigable three-dimensional (3D)-ultrasound is a novel tool for planning and guiding such resections. We review our experience with this system and analyze our initial results, especially with respect to malignant gliomas.Methods
A prospective database for all patients undergoing sononavigation-guided surgery at our center since this surgery’s introduction in June 2011 was queried to retrieve clinical data and technical parameters. Imaging was reviewed to categorize tumors based on enhancement and resectability. Extent of resection was also assessed.Results
Ninety cases were operated and included in this analysis, 75 % being gliomas. The 3D ultrasound mode was used in 87 % cases (alone in 40, and combined in 38 cases). Use of combined mode function [ultrasound (US) with magnetic resonance (MR) images] facilitated orientation of anatomical data. Intraoperative power Doppler angiography was used in one-third of the cases, and was extremely beneficial in delineating the vascular anatomy in real-time. Mean duration of surgery was 4.4 hours. Image resolution was good or moderate in about 88 % cases. The use of the intraoperative imaging prompted further resection in 59 % cases. In the malignant gliomas (51 cases), gross-total resection was achieved in 47 % cases, increasing to 88 % in the “resectable” subgroup.Conclusions
Navigable 3D US is a versatile, useful and reliable intraoperative imaging tool in resection of brain tumors, especially in resource-constrained settings where Intraoperative MR (IOMR) is not available. It has multiple functionalities that can be tailored to suit the procedure and the experience of the surgeon. 相似文献82.
Simon S. Jameson Deborah Lees Philip James Andrew Johnson Christopher Nachtsheim James L. McVie Amar Rangan Scott D. Muller Mike R. Reed 《Injury》2013
Background
The treatment of choice for intracapsular neck of femur (NOF) fractures in younger, more active patients remains unknown. Some surgeons advocate total hip replacement (THR).Aim
This study aimed to compare complications following THR and hemiarthroplasty using the Hospital Episode Statistics (HES) database in England.Method
Dislocation and revision rates were extracted for all patients with NOF fracture who underwent either cemented hemiarthroplasty or cemented THR between January 2005 and December 2008. To make a ‘like for like’ comparison all 3866 THR patients were matched to 3866 hemiarthroplasty patients (from a total of 41,343) in terms of age, sex and Charlson score.Results and conclusion
Eighteen-month dislocation was significantly higher in the THR group (2.4% vs. 0.5%, odds ratio (OR) 3.90 (2.99–5.05), p < 0.001). This difference was sustained at the 4-year stage (2.9% vs. 0.9%, OR 3.18 (1.58–6.94), p = 0.001) in a subset of patients with longer follow-up. There was no significant difference in revision rate up to 4 years (1.8% vs. 2.1%, OR 0.85 (0.46–1.55), p = 0.666). In this national analysis of matched patients short- and medium-term dislocation rates following THR were significantly higher than following cemented hemiarthroplasty, without any difference in revision rates at 4 years. The low risk of dislocation may be acceptable in order to experience the apparent functional benefits of THR. 相似文献83.
84.
Calvaruso V Dhillon AP Tsochatzis E Manousou P Grillo F Germani G Patch D O'Beirne J Burroughs AK 《Journal of gastroenterology and hepatology》2012,27(7):1227-1232
Background and Aims: Current histological scoring systems do not subclassify cirrhosis. Computer‐assisted digital image analysis (DIA) of Sirius Red‐stained sections measures fibrosis morphologically producing a fibrosis ratio (collagen proportionate area [CPA]). CPA could have prognostic value within a disease stage, such as cirrhosis. The aim of the present study was to evaluate CPA in patients with recurrent hepatitis C virus (HCV) allograft cirrhosis and assess its relationship with hepatic venous pressure gradient (HVPG). Methods: In 121 consecutively‐transplanted HCV patients with HVPG, measured contemporaneously with transjugular liver biopsies, 65 had Ishak stage 5 or 6 disease (43 with HVPG measurement). Biopsies were stained with Sirius Red for DIA, and the collagen content was expressed as a CPA. In three cases, a tissue for Sirius Red staining was not obtained, and the patients were excluded. Results: Sixty‐two patients were analyzed. The median HVPG was 8 mmHg (interquartile range [IQR]: 5–10). Portal hypertension (HVPG ≥ 6 < 10 mmHg) was present in 30 (69.8%), and HVPG ≥ 10 mmHg in 13 (30.2%). The median CPA was 16% (IQR 10.75–23.25). Median Child–Pugh score and HVPG were not significantly different between Ishak fibrosis stage 5 or 6, whereas CPA was statistically different: 13% in stage 5 (IQR 8.3–12.4) versus 23% in stage 6 (IQR 17–33.7, P < 0.001). In the multivariate analysis, CPA was the only variable significantly associated with clinically‐significant portal hypertension (HVPG ≥ 10 mmHg, odds ratio: 1.085, confidence interval: 1.004–1.172, P = 0.040). A CPA of 14% was the best cut‐off value for clinically‐significant portal hypertension (CSPH) and liver decompensation, which occurred in 24 patients. Event‐free survival was significantly shorter in patients with CSPH or with a CPA value ≥ 14%, or with a combination of both. Conclusion: In Ishak stages 5 and 6, CPA correlated with HVPG, but had a wider range of values, suggesting a greater sensitivity for distinguishing “early” from “late” severe fibrosis/cirrhosis. CPA was a unique, independent predictor of HVPG ≥ 10 mmHg. CPA can be used to subclassify cirrhosis and for prognostic stratification. 相似文献
85.
86.
The objective of this study was to investigate the effect of freezing of normal plasma samples on protein C, free protein S (FPS) and antithrombin levels in order to determine its potential impact on the interpretation of the results of similarly frozen patients' samples. Protein C, FPS and antithrombin levels were measured by clotting-based test, by sandwich ELISA and by chromogenic assay, respectively, in 50 normal plasma samples prior to freezing, and after 2 and 4 weeks in parallel aliquots frozen at -25°C. The mean levels of the three proteins dropped significantly after a fortnight's freezing, protein C: 130.7-122.8% (P < 0.0246); FPS: 105.9-94.1% (P < 0.0016); antithrombin: 103.2-95.8% (P < 0.0001). The corresponding inter-assay coefficient of variances of the two sets of results were 8.9, 6.6 and 9.3%. Thereafter, only FPS declined significantly (84.3%) (P < 0.0001). In two of 48 and five of 48 cases at the end of 2 and 4 weeks, respectively, the levels of FPS values went below the lower limit of the normal range established from the 50 plasma samples. Freezing of plasma at -25°C for 24 h per se did not alter the levels of protein C and antithrombin and caused only a negligible change in FPS levels. Since 6, 4 and 14% of normal plasma samples would have been labeled as antithrombin, protein C and protein S deficient, respectively, had the tests been performed after 4 weeks of freezing, it is recommended that for correct interpretation of the results, laboratories should establish their reference ranges on normal samples frozen for the same period of time as the patients' samples. 相似文献
87.
88.
Purpose
We present the case of a parturient diagnosed with primary ciliary dyskinesia with secondary bronchiectasis who developed significant hypoxemia following administration of intravenous oxytocin during Cesarean delivery under spinal anesthesia. This case suggests that oxytocin can affect pulmonary vascular tone and interfere with the protective effects of hypoxic vasoconstriction.Clinical features
A 35-yr-old primigravida at 37 weeks gestation presented for a scheduled Cesarean delivery due to breech positioning and fetal abnormalities. The patient had a diagnosis of primary ciliary dyskinesia and had undergone a right middle lobectomy seven years earlier for resultant bronchiectasis. Pulmonary function testing in the month prior to delivery showed a 4% decline in her baseline FEV1 to 1.06 L (32% of predicted value) but she was functionally well. The patient initially had an uneventful spinal anesthetic and maintained an oxygen saturation of 97% on room air in the supine position until delivery of her baby. An intravenous infusion of oxytocin for uterine contraction was started following removal of the placenta. The patient then became acutely hypoxemic with a drop in room air saturation to 84% but with no other accompanying hemodynamic instability. Maternal oxygen saturation did not improve with the addition of supplemental oxygen, and the patient had a significant arterial-alveolar oxygen gradient suggesting an intrapulmonary shunt. No supporting clinical, radiologic, or laboratory evidence of a thrombotic, air, or amniotic fluid embolism or mucous plug was detected. The patient remained hypoxemic during the postoperative period with gradual improvement back to baseline saturation in approximately 48 hr.Conclusion
The vasodilatory effects of intravenous oxytocin on the pulmonary vasculature may worsen shunting and interfere with hypoxic pulmonary vasoconstriction, producing clinically significant hypoxemia in patients with comorbid lung disease. Oxytocin should be used with caution in patients with compromised lung function. 相似文献89.
Morteza Meftah Mario John Matin Lendhey Aleksandr Khaimov Amar S. Ranawat Chitranjan S. Ranawat 《The Journal of arthroplasty》2013
The aim of this study was to assess peri-operative complications, safety and efficacy of non-cemented femoral fixation in total hip arthroplasty (THA) as compared to cemented femoral fixation in the elderly population. Fifty-two matched pair analysis of patients with 75 years of age and older (104 patients), who underwent primary THA from June 1997 to December 2004, was performed based on age, sex, BMI, and Charnley classification. Mean age was 81 years (75–101) and the average follow up was 3.1 ± 2.9 years (1.2–6.4). There was no difference in peri-operative cardiopulmonary complications, pulmonary failures, deep venous thrombosis, pulmonary embolus, length of stay, or discharge deposition between the two groups. Non-cemented fixation is safe and effective in patients older than 75 years of age. 相似文献
90.
Sven Asmussen Dirk M. Maybauer John F. Fraser Kristofer Jennings Shane George Amar Keiralla Marc O. Maybauer 《Burns : journal of the International Society for Burn Injuries》2013
A systematic review and meta-analysis was conducted to assess the level of evidence for the use of extracorporeal membrane oxygenation (ECMO) in hypoxemic respiratory failure resulting from burn and smoke inhalation injury. We searched any article published before March 01, 2012. Available studies published in any language were included. Five authors rated each article and assessed the methodological quality of studies using the recommendation of the Oxford Centre for Evidence Based Medicine (OCEBM). Our search yielded 66 total citations but only 29 met the inclusion criteria of burn and/or smoke inhalation injury. There are no available systematic reviews/meta-analyses published that met our inclusion criteria. Only a small number of clinical trials, all with a limited number of patients, were available. The overall data suggests that there is no improvement in survival for burn patients suffering acute hypoxemic respiratory failure, with the use of ECMO. ECMO run times of less than 200 h correlate with higher survival compared to 200 h or more. Scald burns show a tendency of higher survival than flame burns. 相似文献