Comparison of three ventilatory modes during one-lung ventilation in elderly patients.

OBJECTIVE The purpose of this study was to explore the effects of three different ventilatory modes: volume controlled ventilation (VCV), pressure controlled ventilation (PCV) and pressure controlled ventilation-volume guaranteed (PCV-VG) on arterial oxygenation and airway pressure during one-lung ventilation (OLV) in elderly patients. METHODS We enrolled 66 patients who underwent thoracic surgery requiring at least 1 hour of OLV and aged above 65 years into the study. Patients were classified into VCV, PCV and PCV-VG groups according to a controlled, randomized design. Patients were ventilated to obtain a tidal volume (TV) of 8 mL/kg with three different ventilatory modes during OLV. The Hemodynamic and respiratory data had been recorded during intraoperation and arterial blood gases were obtained at baseline, 20, 40, 60 minutes after OLV, end of surgery. RESULTS Compared with VCV group, Ppeak was significantly lower in PCV and PCV-VG group (P<0.05), and the difference was not found between the PCV and PCV-VG group. PaO2 in PCV and PCV-VG group were higher than 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). CONCLUSIONS Compared with VCV, the use of PCV and PCV-VG have a significant advantage in intraoperative oxygenation and airway pressure for eldly patients undergoing OLV.