Anesthesia and analgesia
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Anesthesia and analgesia · Apr 2014
Intrathecal Injection of JWH015 Attenuates Remifentanil-Induced Postoperative Hyperalgesia by Inhibiting Activation of Spinal Glia in a Rat Model.
Hyperalgesia and neuroinflammation are associated with glia, which consists of macroglia and microglia. In this study, we used a selective cannabinoid receptor type 2 (CB2) agonist JWH015 to investigate remifentanil-induced postoperative hyperalgesia. ⋯ The activation of glia, the production of proinflammatory cytokines, and the expression of CB2 and p-NR2B in the spinal dorsal horn increase significantly during the process of remifentanil-induced hyperalgesia. These changes can be regulated by pretreatment with JWH015, which may be the main mechanism underlying the antihyperalgesia effects of JWH015.
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Anesthesia and analgesia · Apr 2014
When does apparatus dead space matter for the pediatric patient?
Physiologic dead space is defined as the volume of the lung where gas exchange does not occur. Apparatus dead space increases dead space volume, causing either increased PaCO2 or the need to increase minute ventilation to maintain normocapnia. Children are especially vulnerable because small increases in apparatus dead space can significantly increase dead space to tidal volume ratio (Vd/Vt). ⋯ Similarly, RR required to maintain PaCO2 of 40 mm·Hg increased exponentially with increasing dead space. Increasing apparatus Vd can lead to exponential increases in PaCO2 and/or RR required to maintain normal PaCO2. The effect on PaCO2 is less as patient weight increases, but these data suggest it can be significant for typical circuit components up to at least 17 kg or aged 36 months.
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Anesthesia and analgesia · Apr 2014
Serum MMP-8 and TIMP-1 in Critically Ill Patients with Acute Respiratory Failure: TIMP-1 Is Associated with Increased 90-Day Mortality.
Matrix metalloproteinases (MMPs) likely have an important role in the pathophysiology of acute lung injury. In a recent study, high matrix metalloproteinases (MMP-8) levels in tracheal aspirates of pediatric acute respiratory distress syndrome (ARDS) patients were associated with worse outcome. In patients with sepsis, an imbalance between MMPs and their tissue inhibitors (TIMPs) has been associated with impaired survival. We hypothesized that the elevated systemic MMP-8 and TIMP-1 are associated with worse outcome in acute respiratory failure. ⋯ MMP-8 levels were possibly higher in 90-day nonsurvivors but performed poorly in predicting outcome. Increased systemic levels of TIMP-1 were associated with more severe hypoxemia and worse outcome in a large cohort of mechanically ventilated critically ill patients and in a subgroup of ARDS patients.
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Anesthesia and analgesia · Apr 2014
A decrease in spatially resolved near-infrared spectroscopy-determined frontal lobe tissue oxygenation by phenylephrine reflects reduced skin blood flow.
Spatially resolved near-infrared spectroscopy-determined frontal lobe tissue oxygenation (ScO2) is reduced with administration of phenylephrine, while cerebral blood flow may remain unaffected. We hypothesized that extracranial vasoconstriction explains the effect of phenylephrine on ScO2. ⋯ These findings suggest that a phenylephrine-induced decrease in ScO2, as determined by INVOS-4100 near-infrared spectroscopy, reflects vasoconstriction in the extracranial vasculature rather than a decrease in cerebral oxygenation.
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Anesthesia and analgesia · Apr 2014
Dexamethasone produces dose-dependent inhibition of sugammadex reversal in in vitro innervated primary human muscle cells.
Corticosteroids are frequently used during anesthesia to provide substitution therapy in patients with adrenal insufficiency, as a first-line treatment of several life-threatening conditions, to prevent postoperative nausea and vomiting, and as a component of multimodal analgesia. For these last 2 indications, dexamethasone is most frequently used. Due to the structural resemblance between aminosteroid muscle relaxants and dexamethasone, concerns have been raised about possible corticosteroid inhibition in the reversal of neuromuscular block by sugammadex. We thus investigated the influence of dexamethasone on sugammadex reversal of rocuronium-induced neuromuscular block, which could be relevant in certain clinical situations. ⋯ This is the first report in which the effects of rocuronium and sugammadex interactions with dexamethasone have been studied in a highly accessible in vitro experimental model of functionally innervated human muscle cells. Sugammadex reverses rocuronium-induced neuromuscular block; however, concomitant addition of high dexamethasone concentrations diminishes the efficiency of sugammadex. Further studies are required to determine the clinical relevance of these interactions.