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Hip fractures are becoming increasingly common in a growing elderly population, and are associated with significant morbidity and mortality. Displaced intracapsular femoral neck fractures are usually treated with either total hip arthroplasty (THA) or hemiarthroplasty, although the indication for each operation remains an area for debate. THA has been associated with longer operative time, increased risk of dislocation and a slight increase in general complications compared with hemiarthroplasty. However, it has also been associated with a modest improvement in functional outcomes and quality of life. Guidelines have been created within the UK to aid the decision-making process based upon current available literature. The principal focus of these has been to identify patients suitable for THA, and include patients who are cognitively intact, mobile outside their home with the use of no more than one stick, and who are medically fit enough for the procedure. However, implant selection must also be taken into consideration in order to achieve the best outcomes for patients. Options for implants include use of dual mobility cups and choice of femoral head size in THA, bipolar versus unipolar hemiarthroplasty, and cemented versus uncemented implants. Further research is required into this area to make additional recommendations.  相似文献   
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Background

Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.

Methods

In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.

Results

In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.

Conclusion

During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.

Registration of Clinical Trial

DRKS-ID DRKS00014788 ( www.drks.de ).  相似文献   
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The aims of this paper were to validate a modification of an extended total temporomandibular joint replacement (eTMJR) classification system and develop a classification schematic for ease of reference. High-volume TMJ surgeons were asked to score 20 separate eTMJR devices using the updated classification system, and inter-rater variability was calculated. Using the modified classification system developed, a Conger’s kappa (κ) coefficient of 0.53 was returned, suggesting moderate to good levels of agreement. The final classification system was then developed in a series of standardised graphic illustrations as visual representations of the different subcategories of eTMJR devices.  相似文献   
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