title: Auto-positive end-expiratory pressure during one-lung ventilation using a double-lumen endobronchial tube.
abstract: The present study was undertaken to investigate the possible relationships between the magnitude of autopositive end-expiratory pressure (auto-PEEP) and measured PaO2 during one-lung ventilation (OLV). Forty-one adults received OLV anesthesia using a tidal volume of 8 mL/kg and a respiratory rate of 12 breaths/min. Auto-PEEP was quantified using an end-expiratory port occlusion method. During two-lung ventilation (2LV), auto-PEEP was observed in 18 of 41 patients and ranged from 0.5 to 2.5 cm H2O. During OLV, auto-PEEP was observed in 34 of 41 patients and ranged from 0.5 to 10 cm H2O. The mean (+/- SD) value of auto-PEEP was significantly higher during OLV than during 2LV (3.2 +/- 3.3 cm H2O versus 0.5 +/- 0.7 cm H2O, P < 0.0001). Auto-PEEP during OLV correlated inversely with preoperative forced expiratory volume in 1 s/forced vital capacity (y = 12.5 - 0.13x, r = -.05, P < 0.005). During OLV, there was no significant correlation between auto-PEEP and measured PaO2. These findings confirm that many patients do not exhale completely to functional residual capacity during OLV.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Kawasaki Medical School, Okayama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yokota
authors.forename: T
authors.initials: T
authors.lastname: Toriumi
authors.forename: A
authors.initials: A
authors.lastname: Sari
authors.forename: S
authors.initials: S
authors.lastname: Endou
authors.forename: M
authors.initials: M
authors.lastname: Mihira
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D005260:Female; D005541:Forced Expiratory Volume; D005652:Functional Residual Capacity; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008168:Lung / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011175:Positive-Pressure Respiration; D012119:Respiration; D013990:Tidal Volume; D014797:Vital Capacity
chemical_list: D010100:Oxygen