Protective effect of dexmedetomidine against myocardial ischemia-reperfusion injury in rabbits

Abstract Purpose: To investigate the influence of dexmedetomidine on myocardial ischemia-reperfusion injury (IRI) in rabbits. Methods: Twenty-four New Zealand white rabbits were randomly divided into two equal-sized groups: IRI group (group IR) and dexmedetomidine group (group D). Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), left ventricular diastolic pressure (LVDP), +dp/dtmax, -dp/dtmax, and t-dp/dtmax were recorded and calculated at the following time points: before (T0) and after (T1) dexmedetomidine infusion, after 30-min ischemia (T2), and after 120-min reperfusion (T3). The levels of plasma endothelin 1 (ET-1), thromboxane A2 (TXA2), and platelet activating factor (PAF); area of myocardial infarction (MI); and no-reflow area were evaluated. Results: SBP, DBP, LVSP, LVEDP, LVDP, and +dp/dtmax at T3 were higher in group D than in group IR (P<0.05). The average no-reflow area in group IR was significantly smaller than that in group D (14±3% vs. 38±5%, P=0.0116). The ET-1, TXA2, and PAF levels at T2 and T3 were higher than those at T0 in both groups (P<0.05). Conclusion: Dexmedetomidine could reduce the magnitude of ischemic myocardial no-reflow area and protect the myocardium with ischemia-reperfusion injury.

Clinical characteristics of 57 patients with early stage esophageal cancer or precancerosis treated with esophagectomy following endoscopic submucosal dissection / 中国胸心血管外科临床杂志

@#Objective    To analyze the clinical characteristics of patients treated with esophagectomy following endoscopic submucosal dissection (ESD) for early stage esophageal cancer or precancerosis and the reasons for esophagectomy. Methods    We retrospectively analyzed the clinical data of 57 patients who were treated with esophagectomy following ESD in West China Hospital and Shanxian Hygeia Hospital from January 2012 through October 2016. There were 42 males and 15 females at age of 65.4 (52–77) years. There were 15 patients of upper thoracic lesions, the middle thoracic lesions in 34 patients, and the lower thoracic lesions in 8 patients. Results    The reasons for esophagectomy included 3 patients with residual tumor, 8 patients with local recurrence, 37 patients with esophageal stricture, and 9 patients with dysphagia, although the diameter was larger than 1.0 cm. The pathology after esophagectomy revealed that tumor was found in 16 patients, including 3 patients with residual tumor and 8 with recurrent tumor confirmed before esophagectomy, and 5 patients with new-found recurrent tumor. Conclusion    In the treatment of early stage esophageal cancer or precancerosis, the major reasons for esophagectomy following ESD include esophageal stricture, abnormal esophageal dynamics, local residual or recurrence.