Anesthesia and analgesia
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Anesthesia and analgesia · Mar 2016
Human Lumbar Ligamentum Flavum Anatomy for Epidural Anesthesia: Reviewing a 3D MR-Based Interactive Model and Postmortem Samples.
The ligamentum flavum (LF) forms the anatomic basis for the loss-of-resistance technique essential to the performance of epidural anesthesia. However, the LF presents considerable interindividual variability, including the possibility of midline gaps, which may influence the performance of epidural anesthesia. We devise a method to reconstruct the anatomy of the digitally LF based on magnetic resonance images to clarify the exact limits and edges of LF and its different thickness, depending on the area examined, while avoiding destructive methods, as well as the dissection processes. ⋯ The major anatomical features of the LF were reproduced in the 3D model. Details of its structure and variations of thickness in successive sagittal and axial slides could be visualized. Gaps within LF previously studied in cadavers have been identified in our interactive 3D model, which may help to understand their nature, as well as possible implications for epidural techniques.
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When adding new markers to existing prediction models, it is necessary to evaluate the models to determine whether the additional markers are useful. The net reclassification improvement (NRI) has gained popularity in this role because of its simplicity, ease of estimation, and understandability. Although the NRI provides a single-number summary describing the improvement new markers bring to a model, it also has several potential disadvantages. ⋯ Also, overfitting, or otherwise misspecified training models, produce overly positive NRI results. Because of the unaccounted for uncertainty in the model coefficient estimation, investigators should rely on bootstrapped confidence intervals rather than on tests of significance. Keeping in mind the limitations and drawbacks, the NRI can be helpful when used correctly.
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Anesthesia and analgesia · Mar 2016
The Effectiveness and Stability of a 20% Emulsified Sevoflurane Formulation for Intravenous Use in Rats.
Halogenated volatile anesthetics can be safely and rapidly administered to animals and humans using emulsion formulations. However, they must be administered simultaneously with a high dose of lipids. Increasing the concentration of volatile anesthetics may solve this clinical issue. Moreover, careful observation is needed when the emulsion is injected because anaphylactic reactions have been reported. ⋯ We prepared a 20% sevoflurane lipid emulsion using caprylic triglyceride (i.e., medium-chain triglyceride). In rats, this emulsion was an effective anesthetic and was not associated with adverse events. The emulsion was stable after consecutive evaluation for 365 days and for 180 minutes after the vial was opened.
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Anesthesia and analgesia · Mar 2016
Electroacupuncture Relieves Nerve Injury-Induced Pain Hypersensitivity via the Inhibition of Spinal P2X7 Receptor-Positive Microglia.
Electroacupuncture (EA) has therapeutic effects on neuropathic pain induced by nerve injury; however, the underlying mechanisms remain unclear. In this study, we examined whether EA treatment relieves pain hypersensitivity via the down-regulation of spinal P2X7 receptor-positive (P2X7R⁺) microglia-mediated overexpression of interleukin (IL)-1β and/or IL-18. ⋯ EA treatment relieves nerve injury-induced tactile allodynia and thermal hyperalgesia via the inhibition of P2X7R⁺ microglia-mediated IL-1β overexpression.
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Anesthesia and analgesia · Mar 2016
R-Duloxetine and N-Methyl Duloxetine as Novel Analgesics Against Experimental Postincisional Pain.
Antidepressant S-duloxetine alleviates intractable pain associated with diabetic peripheral neuropathy and fibromyalgia. It also reduces both acute and persistent pain in various animal models. This study addresses whether the enantiomer, R-duloxetine, and the homolog, N-methyl duloxetine, could act as analgesics and whether they block neuronal Na⁺ channels. ⋯ R-Duloxetine and N-methyl duloxetine are highly effective against postoperative pain using the skin incision model, and they elicit both tonic and use-dependent block of neuronal Na⁺ channels. Our results suggest that R-duloxetine and N-methyl duloxetine are applicable as novel analgesics.