Effects of Different Ventilation Modes on Respiration and Circulation in Elderly Patients Undergoing Thoracic Surgery

［Abstract］Objective The aim of this study was to explore the effects of volume controlled ventilation （VCV），pressure controlled ventilation（PCV）and pressure controlled ventilation-volume guaranteed （PCV-VG）on respiration and circulation in elderly patients undergoing thoracic surgery. Methods Thirty-six elderly patients who underwent thoracic surgery were enrolled in our study. Patients were divided into VCV， PCV and PCV-VG groups according to randomized design. The hemodynamic and respiratory data and the arterial blood gases had been recorded in the pre-operation，20 min，40 min，60 min after OLV and 20 min after the resumption of two lung ventilation. Results Compared with VCV group，Ppeak value was significantly lower in PCV and PCV-VG groups （P < 0.05）， and the difference was not found between the PCV and PCV-VG groups. PaO2 levels in PCV and PCV-VG groups were higher than that in VCV group after the point of OLV+40 （P < 0.05）. Comparison of PCV group， PaO2 in PCV-VG group was higher， but did not show a significantly improved during OLV（P > 0.05）. Conclusion Compared with VCV， the use of PCV and PCV-VG have significant advantages in the operative oxygenation and airway pressure for elderly patients undergoing OLV.