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Purpose: To evaluate the role of the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt)/hypoxia-inducible factor 1α (HIF-1α) signaling pathway in the protection by dexmedetomidine against lung ischemia-reperfusion injury (IRI) in rats., Methods: Forty-eight male Sprague-Dawley rats weighing 250-350 g were randomly divided into six groups (n = 8 each group): sham group, IRI group, low-dose dexmedetomidine group (LD group), high-dose dexmedetomidine group (HD group), combined low-dose dexmedetomidine and LY294002 group (LDL group), and combined high-dose dexmedetomidine and LY294002 group (HDL group). A 30-min ischemia was induced by occluding the hilum of the left lung, followed by a 120-min reperfusion by removing occlusion of the hilum. After the left lung was removed, the wet/dry weight ratio (W/D) of the lung tissues was determined. Pathological changes of lung tissues were evaluated by light and electron microscopes and the expression of p-Akt and HIF-1α in the lung tissues was determined by western blotting., Results: Compared with the sham group, both the W/D ratio and lung injury were significantly increased, the p-Akt expression was down-regulated and HIF-1α expression was up-regulated in the five experimental groups. Compared with the LD and LDL groups, both the W/D ratio and lung injury were decreased, but the expression of p-Akt and HIF-1α was increased in the HD and HDL groups., Conclusions: Administration of dexmedetomidine before ischemia can provide a protection against lung IRI by re-installing the PI3K/Akt/HIF-1α signaling pathway.

Within the airway management field, simulation has been used as a tool of training for over 40 years. Simulation training offers a chance of active involvement for the trainees. It can effectively enhance and upgrade the knowledge and skills of the trainees in airway management, and subsequently decrease medical errors and improve patients' outcomes and safety through a variety of airway management training modalities, such as common airway skills, difficult airway management strategies, and crisis management skills. To perform simulation-based airway management training effectively, not only are task trainers and high-fidelity simulators required but also instructors with rich experience in airway management simulation training and optimal curriculum design are essential.

Background: The combination of various interventions to obtain enhanced cardioprotection is always an important area of research focus. This randomized experiment was designed to assess whether combined fentanyl and limb remote ischemic postconditioning produced enhanced protection against myocardial ischemia/reperfusion injury in an in vivo rat model, and to determine if κ-opioid receptors were implicated in the cardioprotection of these interventions., Methods: Seventy-two rats were exposed to a 30-min myocardial ischemia followed by a 180-min reperfusion. Half of the rats (36) were randomized into four different groups receiving control treatment, fentanyl postconditioning, limb remote ischemic postconditioning, and combined fentanyl and limb remote ischemic postconditioning. The remaining 36 rats were also randomized into four groups receiving the same interventions as the above groups following the intravenous administration of a κ-opioid receptor antagonist, nor-binaltorphimine, before myocardial ischemia. At the end of reperfusion, both serum cardiac troponin I and infarct size were determined., Results: Both fentanyl postconditioning and limb remote ischemic postconditioning significantly decreased the infarct size and serum cardiac troponin I level, and combined fentanyl and limb remote ischemic postconditioning produced enhanced cardioprotection on the infarct size-sparing effect. The use of nor-binaltorphimin to block κ-opioid receptors eliminated cardioprotection by fentanyl postconditioning and enhanced cardioprotection by combined fentanyl and limb remote ischemic postconditioning, but did not change cardioprotection by limb remote ischemic postconditioning., Conclusions: Combined fentanyl and limb remote ischemic postconditioning produced enhanced protection against myocardial ischemia/reperfusion injury. κ-Opioid receptors are essential for cardioprotection by fentanyl postconditioning and enhanced cardioprotection by combined fentanyl and limb remote ischemic postconditioning; however, they do not play a pivotal role in cardioprotection by limb remote ischemic postconditioning.