Objective:To study the effects of dexmedetomidine(DEX) on perioperative myocardial injury in elderly patients with single lung ventilation(OLV). Methods: Sixty elderly patients with esophageal cancer radical (ASA Ⅰ-Ⅱ) were enrolled in this study. The patients were divided into two groups by random number method. The test group (n=30) were induced using DEX 1.0 μg·kg-1,and the injection was completed in 10 min. After induction,they were received the DEX 0.6 μg·kg-1·h-1 until the end of the operation. The control group(n=30) were received the normal volume of saline.Systemic anesthesia was used in all cases,and bilateral endotracheal intubation was performed. At the time point of the before induction(T0),OLV for 30 min(T1), the end of operation(T2), 24 h after surgery(T3),brain natriuretic peptide(BNP) and troponin (cTnT)were detected. The mean arterial pressure(MAP) and heart rate(HR)were recorded at the time of entering the operating room(T0'), inserting thedouble lumen endotracheal tube(T4),cutting skin(T5) and inserting the single lumen endotracheal tube(T6).Results: The differences of BNP, cTnT, MAP, HR between the two groups at T0 or T0'had no statistical significance (P>0.05). Compared with T0, BNP and cTnT of the two groupswere significantly higher at T2 and T3 (all P<0.01), butthe BNP and cTnT of the test group were significantly lower than those of the control group(all P<0.05).Compared with T0', the changes of MAP and HR at T4, T5 and T6 of the test group were not obvious (all P>0.05), butthe MAP and HR of the test groupwere significantly lower than those of the control group (all P<0.05).Conclusion: The application of DEX can significantly reduce perioperative myocardial injury and improve perioperative hemodynamics in elderly patients with single lung ventilation. |