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Background
Previous studies suggest that dexmedetomidine has a protective effect against local anaesthetic-induced nerve injury in regional nerve blocks. Whether this potentially protective effect exists in the context of diabetes mellitus is unknown.Methods
A diabetic state was established in adult male Sprague–Dawley rats with intraperitoneal injection of streptozotocin. Injections of ropivacaine 0.5%, dexmedetomidine 20 μg kg?1 (alone and in combination), or normal saline (all in 0.2 ml) were made around the sciatic nerve in control and diabetic rats (n=8 per group). The duration of sensory and motor nerve block and the motor nerve conduction velocity (MNCV) were determined. Sciatic nerves were harvested at post-injection day 7 and assessed with light and electron microscopy or used for pro-inflammatory cytokine measurements.Results
Ropivacaine and dexmedetomidine alone or in combination did not produce nerve fibre damage in control non-diabetic rats. In diabetic rats, ropivacaine induced significant nerve fibre damage, which was enhanced by dexmedetomidine. This manifested with slowed MNCV, decreased axon density, and decreased ratio of inner to outer diameter of the myelin sheath (G ratio). Demyelination, axon disappearance, and empty vacuoles were also found using electron microscopy. An associated increase in nerve interleukin-1β and tumour necrosis factor-α was also seen.Conclusions
Ropivacaine 0.5% causes significant sciatic nerve injury in diabetic rats that is greatly potentiated by high-dose dexmedetomidine. Although the dose of dexmedetomidine used in this study is considerably higher than that used in clinical practice, our data suggest that further studies to assess ropivacaine (alone and in combination with dexmedetomidine) use for peripheral nerve blockade in diabetic patients are warranted. 相似文献Background
In cardiothoracic surgery, little data exist on the transition to operative independence. We aimed to compare current perceptions of operative autonomy of junior cardiothoracic surgeons and senior colleagues who oversee transitional years.Methods
An anonymous online survey was sent to currently practicing North American board-certified/eligible cardiothoracic surgeons to assess reported time to operative independence and comfort with cardiothoracic operations. The χ2 test, Fisher exact test, and Mann-Whitney U test were used to compare junior surgeons’ self-reported experience to the junior experience as reported by the midcareer and senior surgeons with whom they practiced. Logistic regression was performed to assess factors associated with operative independence.Results
Responses from 436 completed surveys were analyzed (82 juniors and 354 midcareer/seniors). Two hundred fifty-four midcareer/senior surgeons reported on the experience of 531 junior partners. Juniors reported high immediate posttraining comfort with basic cardiac cases and moderate comfort with all other categories. Time to operative independence was significantly different between juniors' self-report and midcareer/senior reports of junior partners except for complex thoracic cases. In multivariable logistic regression analysis, senior, and not midcareer, surgeon status was independently associated with junior operative independence status for cardiac cases and for basic thoracic cases.Conclusions
Most junior surgeons perceived operative independence with basic thoracic, basic cardiac, and complex cardiac operations earlier in their surgical career than that reported by senior colleagues. Objective measures of operative independence may clarify this discrepancy. This study establishes a baseline by which to compare the effects of integrated 6-year programs on operative independence. The discrepant perceptions may have implications for how training programs prepare graduates for the transition to independent practice. 相似文献Introduction
Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.Methods
We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.Results
We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.Conclusion
By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation. 相似文献Methods: Nutrient intakes of total, base and food donation diets were estimated for 112 food pantry recipients using specific questionnaires; and then compared to the dietary reference intakes (DRI) and 2015–2020?US Dietary Guidelines.
Results: Food donations accounted for more than half of the client’s daily intake of energy, carbohydrates, vitamin B6, phosphorus, copper and selenium. Yet, daily total intake remained less than their DRIs for carbohydrates, poly-unsaturated fats, dietary fiber, fat soluble vitamins and vitamin C, and was even lower for calcium, magnesium and potassium. Total food intake of clients almost met the US Dietary Guidelines for refined grains, fruits, vegetables, and meat; however, the amount of whole grains and dairy was inadequate.
Conclusions: Supplemental foods offered at food pantries are an important resource for improving nutrient intake of low-income populations. 相似文献