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31.
It is unclear which criteria should be used to define readiness for tracheal extubation in the operating theatre. We studied the effects of desaturation in the operating theatre immediately after tracheal extubation on long-term outcomes. Performing a pre-specified, retrospective analysis of 71,025 cases involving previously independent adults undergoing non-cardiac surgery, we evaluated the association between desaturation events (oxygen saturation < 90%) within 10 min of tracheal extubation and adverse discharge (to a skilled nursing facility or long-term care facility). A total of 404 (12.3%) cases with, and 5035 (7.4%) cases without, early postoperative desaturation had an adverse discharge. Early postoperative desaturation was associated with higher odds of being discharged to a nursing facility (adjusted odds ratio 1.36 (95%CI 1.20–1.54); p < 0.001). Increased duration of desaturation augmented the effect (p for trend < 0.001). Desaturation was associated with a higher risk of respiratory, renal and cardiovascular complications as well as increased duration of hospital stay, postoperative intensive care unit admission frequency and cost. Several modifiable factors were associated with desaturation including: high intra-operative long-acting opioid administration; high neostigmine dose; high intra-operative inspired oxygen concentration; and low oxygen delivery immediately before tracheal extubation. There was substantial provider variability between anaesthetists in the incidence of postoperative desaturation unexplained by patient- and procedure-related factors. Early postoperative desaturation is a potentially preventable complication associated with a higher risk of adverse discharge disposition. Anaesthetists may consider developing guidelines to define tracheal extubation readiness that contain postoperative desaturation as an adverse outcome after tracheal extubation.  相似文献   
32.
The binding of an 125I-labeled analog of ACTH, [125I]Tyr23,Phe2,Nle4-ACTH-(1-38), to differentiated 3T3-L1 fat cells was characterized. Time-dependent binding, which was inhibited by saturating concentrations of unlabeled ACTH (0.44 microM), could be demonstrated in the differentiated cells. Using 0.4 nM [125I]ACTH analog and increasing concentrations of ACTH, the half-maximal concentration for inhibition by ACTH was 4.3 nM. Scatchard analysis demonstrated a single class of ACTH binding. There were approximately 3500 binding sites/cell. The binding of [125I]ACTH analog was specific in that it could be displaced by ACTH, ACTH-(1-19), ACTH-(1-17), and N-acetyl-Ser1-ACTH, but not by high concentrations of insulin, beta-endorphin, or polylysine. There was an excellent correlation between the ability of ACTH and its analogs to inhibit [125I]ACTH analog binding and the ability of ACTH and its analogs to stimulate cAMP production. In contrast, no saturable binding could be demonstrated when undifferentiated 3T3-L1 fibroblasts, which are not responsive to ACTH, were studied. Thus, differentiation of 3T3-L1 cells into the adipocyte form is accompanied by the appearance of receptors for ACTH. These receptors allow the adipocytes to respond to ACTH.  相似文献   
33.

Background:

The major neurovascular involvement and large primary tumors are indication of amputation. The present study is an attempt to explore the feasibility of a limb salvage surgery in extremity sarcoma cases with major vessel involvement. Oncological outcomes and surgery-related morbidities are compared with those reported in literature.

Materials and Methods:

A retrospective review of all limb salvage surgeries done in our department between 2005 and 2008 was done and four cases of extremity sarcoma of lower limb involving femoral vessels analyzed. Interpretation of data from these cases, along with review of literature, is done.

Results:

In all these cases a wide monobloc excision was done adhering to oncological principles. This required resection of superficial femoral artery alone in two cases, resection of superficial femoral artery along with common femoral vein and femoral nerve in another, and of common femoral vein alone in yet another. Reconstruction was done in all these cases with reversed long saphenous vein graft. Histopathology of resected margins was free of tumor in all the four patients. One patient developed local recurrence and one developed distant metastsis. Two were disease free for one year with good functional limb, one has been disease-free for three years and another was disease-free at two years, after which he defaulted further follow-up. One patient developed arterial blowout which required ligation of common femoral artery which resulted in gangrene of the limb. He underwent amputation.

Conclusion:

Major neurovascular involvement in extremity sarcoma is not considered a contraindication for limb salvage surgery. Review of literature also supports our view. Post-operative wound related complications are more in this group of patients. However, long term functional outcome is good. Literature suggests a good long term local control after vascular resection and reconstruction.  相似文献   
34.
We analysed the results of 24 cases of aggressive benign and malignant tumours of the distal radius treated by resection and prosthetic replacement between 1995 and 2006. Patient ages ranged from 18 to 74 years, averaging 33 years; 18 were males. Recurrent giant cell tumour was the most common tumour. The prosthesis used was a bipolar hinge custom mega prosthesis manufactured locally. Average follow-up was 78 months. The average Musculoskeletal Tumor Society (MSTS) functional score achieved was 75%. The ten-year prosthesis survival was rate 87.5%. Infection was the most common complication.
Resume  Prothèses sur mesure dans les tumeurs du radius distal. Indications de remplacement. Nous avons analysé les résultats de 24 cas de tumeurs malignes et bégnines agressives de l’extrémité distale du radius traitées par résection et prothèses entre 1995 et 2006. Les patients étaient agées de 18 à 74 ans avec un age moyen de 33 ans dont- 18 étaient des hommes. La cause la plus fréquente a été la récidive de tumeur à cellules géantes. La prothèse utilisée était une prothèse bipolaire à charnière sur mesure fabriquée localement. Le suivi moyen a été de 78 mois. Le score moyen MSTS après traitement était de 75%, la courbe de survie à 10 ans de 87,5%. La complication la plus fréquente a été l’infection.
  相似文献   
35.
OBJECTIVE: Vascular remodeling in response to injury or low shear stress (or both) is characterized by neointimal hyperplasia and luminal contraction. When profound, the response leads to restenosis after percutaneous endovascular intervention as well as to de novo stenosis in vein grafts. It has recently been reported that exposure of vein patches to neurovirulence-attenuated Herpes simplex virus-1 (HSV-1) decreases neointimal hyperplasia and increases luminal area. This experiment tested the hypothesis that R7020, a more highly attenuated mutant of HSV-1, would modulate the vascular remodeling response of experimental vein grafts chronically exposed to low shear stress. METHODS: The external jugular veins of 31 New Zealand white rabbits were clamped and intraluminally exposed to vehicle (phospate-buffered saline solution, n = 11), R7020 2.5 x 10(8) plaque forming units [PFU]/mL (n = 8), or R7020 2.5 x 10(9) PFU/mL (n = 12) for 10 or 30 minutes at an average pressure of 80 mm Hg. After exposure, an end-to-side distal external jugular-to-common carotid artery anastomosis was created, resulting in a widely patent arteriovenous fistula. The external jugular was suture-ligated just proximal to the thoracic inlet, distal to a small 10- to 50-microm venous tributary, creating a reversed vein "graft" segment immediately and abruptly exposed to arterial pressure (48 +/- 3 mm Hg) and low shear stress (0.12 +/- .02 dyne/cm(2)). In the 29 animals (N = 31) that survived to harvest, 26 grafts were found to be patent and were analyzed further. Nine grafts were harvested within the first week after operation, snap frozen in liquid nitrogen, and assayed for the presence of the Herpes viral immediate-response protein ICP0 by Western blot analysis. The 17 remaining grafts were perfusion-fixed, excised, stained, and analyzed morphometrically by digital planimetry. RESULTS: In patent grafts, the hemodynamic environment of low shear stress was maintained (shear stress at harvest, 0.26 +/- .06 dyne/cm(2)). Western blot analysis revealed the presence of ICP0 in R7020-exposed vein grafts after 2, 3, 7, and 14 days; ICP0 was not detected in unexposed vein grafts or adjacent carotid arteries. After 4 weeks, vein grafts exposed to R7020 exhibited a statistically significantly increased ratio of luminal radius to wall thickness, indicating altered remodeling (vehicle, 6.7 +/- 1.3; R7020 2.5 x 10(8), 9.1 +/- 1.3; R7020 2.5 x 10(9) ratio, 11.3 +/- 1.4; P < .05 for high dose compared with vehicle). CONCLUSION: A brief exposure of the neurovirulence-attenuated HSV-1 strain R7020 results in an increased ratio of luminal radius to wall thickness in experimental vein grafts chronically exposed to low shear stress.  相似文献   
36.
Gene therapy for the extension of vein graft patency: a review   总被引:4,自引:0,他引:4  
The mainstay of treatment for long-segment small-vessel chronic occlusive disease not amenable to endovascular intervention remains surgical bypass grafting using autologous vein. The procedure is largely successful and the immediate operative results almost always favorable. However, the lifespan of a given vein graft is highly variable, and less than 50% will remain primarily patent after 5 years. The slow process of graft malfunction is a result of the vein's chronic maladaptive response to the systemic arterial environment, its primary component being the uncontrolled proliferation of vascular smooth muscle cells (SMCs). It has recently been suggested that this response might be attenuated through pre-implantation genetic modification of the vein, so-called gene therapy for the extension of vein graft patency. Gene therapy seems particularly well suited for the prevention or postponement of vein graft failure since: (1) the stimulation of SMC proliferation appears to largely be an early and transient process, matching the kinetics of current gene transfer technology; (2) most veins are relatively normal and free of disease at the time of bypass allowing for effective gene transfer using a variety of systems; and (3) the target tissue is directly accessible during operation because manipulation and irrigation of the vein is part of the normal workflow of the surgical procedure. This review briefly summarizes the current knowledge of the incidence and basic mechanisms of vein graft failure, the vector systems and molecular targets that have been proposed as possible pre-treatments, the results of experimental genetic modification of vein grafts, and the few available clinical studies of gene therapy for vascular proliferative disorders.  相似文献   
37.
Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.  相似文献   
38.
Type 2 diabetes mellitus is associated with a marked increase in the risk of coronary heart disease (CHD) or stroke (by a factor of two to three compared with non-diabetic patients), and cardiovascular disease (CVD) accounts for the majority of deaths among patients with diabetes. A new fixed dose combination containing atorvastatin 10 mg + metformin SR 500 mg is being introduced in the Indian market for the treatment of dyslipidaemia in diabetic patients. The present study was therefore undertaken to assess efficacy, safety and tolerability of a fixed dose combination of atorvastatin 10mg + metformin SR 500mg in adult Indian patients with diabetic dyslipidaemia. The final protocol was approved by relevant ethics committee before the initiation of study. Informed consent was obtained from all the patients prior to enrollment in study. The total duration of study was 14 weeks including two weeks dietary run in period. Patients fulfilling the selection criteria received a single oral tablet of fixed dose combination of atorvastatin 10mg + metformin SR 500mg once daily for 12 weeks. The primary efficacy parameters were assessed by evaluating reduction in fasting and postprandial plasma glucose concentration levels at baseline and thereafter at each follow up visit at 2, 4, 8 and 12 weeks and plasma lipid profile and glycosylated Hb levels at baseline and end of study. The secondary efficacy parameters were assessed by evaluating percentage change from baseline at the end of the study (week 12) in the plasma concentration of the various lipid parameters such as total, HDL-, LDL- and very low density (VLDL)-cholesterol, triglycerides, Apo B, Apo A1, TC/LDL ratio, LDL/ HDL ratio, and percentage of patients achieving LDL-cholesterol goals as per NCEP ATP III guidelines. A total of 213 patients were enrolled in the study. Of these seven patients were lost to follow-up and considered as drop-outs. Therapy with the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg resulted in a significant reduction in the mean plasma fasting and postprandial glucose levels (35 and 38.8% respectively). There was a steep fall in the HbA1c levels from baseline levels of 8.76% to 6.74% (23.1%). There was also a significant (p < 0.05) reduction in mean total cholesterol (31.2%), LDL cholesterol (35.4%), VLDL-cholesterol (19.6%) and a significant increase HDL-cholesterol (9.5%). Thus there appeared to be trend towards reducing atherosclerosis following therapy with the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg. Mean body mass index was significantly reduced in the patients in the present study following therapy with the study drugs. The fixed dose combination of atorvastatin with metformin was well tolerated with mostly gastro-intestinal adverse events being reported in the current study. Moreover, most of the adverse events were mild to moderate in intensity and disappeared with continued treatment. In conclusion, the results of the present study suggest that, the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg is efficacious and well tolerated therapeutic modality in patients with diabetic dyslipidaemia. Furthermore this combination offers dosage convenience to the patient and by virtue of its dual mode of action is a useful addition to the therapeutic armamentarium for patients with diabetic dyslipidaemia.  相似文献   
39.
Effect of alcohol on viral hepatitis and other forms of liver dysfunction   总被引:1,自引:0,他引:1  
Alcohol is a known hepatotoxic agent, which may exacerbate liver injury caused by other agents. The wide prevalence of alcohol use and abuse in society makes it an important cofactor in many other liver diseases. Examples of liver diseases that are significantly influenced by ingestion of alcohol include chronic viral hepatitis, disorders of iron overload, and obesity-related liver disease.  相似文献   
40.
Left ventricular assist devices(LVAD) are increasingly become common as life prolonging therapy in patients with advanced heart failure. Current devices are now used as definitive treatment in some patients given the improved durability of continuous flow pumps. Unfortunately, continuous flow LVADs are fraught with complications such as gastrointestinal(GI) bleeding that are primarily attributed to the formation of arteriovenous malformations. With frequent GI bleeding, antiplatelet and anticoagulation therapies are usually discontinued increasing the risk of life-threatening events. Small bowel bleeds account for 15%as the source and patients often undergo multiple endoscopic procedures.Treatment strategies include resuscitative measures and endoscopic therapies.Medical treatment is with octreotide. Novel treatment options include thalidomide, angiotensin converting enzyme inhibitors/angiotensin Ⅱ receptor blockers, estrogen-based hormonal therapies, doxycycline, desmopressin and bevacizumab. Current research has explored the mechanism of frequent GI bleeds in this population, including destruction of von Willebrand factor,upregulation of tissue factor, vascular endothelial growth factor, tumor necrosis factor-α, tumor growth factor-β, and angiopoetin-2, and downregulation of angiopoetin-1. In addition, healthcare resource utilization is only increasing in this patient population with higher admissions, readmissions, blood product utilization, and endoscopy. While some of the novel endoscopic and medical therapies for LVAD bleeds are still in their development stages, these tools will yet be crucial as the number of LVAD placements will likely only increase in the coming years.  相似文献   
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