title: Effects of Alveolar Recruitment and Positive End-Expiratory Pressure on Oxygenation during One-Lung Ventilation in the Supine Position.
abstract: OBJECTIVE
  Hypoxemia during one-lung ventilation (OLV) remains a serious problem, particularly in the supine position. We investigated the effects of alveolar recruitment (AR) and positive end-expiratory pressure (PEEP) on oxygenation during OLV in the supine position.
  
  
  METHODS
  Ninety-nine patients were randomly allocated to one of the following three groups: a control group (ventilation with a tidal volume of 8 mL/kg), a PEEP group (the same ventilatory pattern with a PEEP of 8 cm H₂O), or an AR group (an AR maneuver immediately before OLV followed by a PEEP of 8 cm H₂O). The tidal volume was reduced to 6 mL/kg during OLV in all groups. Blood gas analyses, respiratory variables, and hemodynamic variables were recorded 15 min into TLV (TLV(baseline)), 15 and 30 min after OLV (OLV₁₅ and OLV₃₀), and 10 min after re-establishing TLV (TLV(end)).
  
  
  RESULTS
  Ultimately, 92 patients were analyzed. In the AR group, the arterial oxygen tension was higher at TLV(end), and the physiologic dead space was lower at OLV₁₅ and TLV(end) than in the control group. The mean airway pressure and dynamic lung compliance were higher in the PEEP and AR groups than in the control group at OLV₁₅, OLV₃₀, and TLV(end). No significant differences in hemodynamic variables were found among the three groups throughout the study period.
  
  
  CONCLUSIONS
  Recruitment of both lungs with subsequent PEEP before OLV improved arterial oxygenation and ventilatory efficiency during video-assisted thoracic surgery requiring OLV in the supine position.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yong Seon
authors.initials: YS
authors.lastname: Choi
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Bae
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Shin Hyung
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ji-Eun
authors.initials: JE
authors.lastname: Park
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. yjoh@yuhs.ac.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Oh
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D000860:Hypoxia; D008168:Lung / Q000503:physiopathology; D008170:Lung Compliance / Q000502:physiology; D008297:Male; D008875:Middle Aged; D061810:One-Lung Ventilation / Q000379:methods*; D010100:Oxygen / Q000097:blood*; D011175:Positive-Pressure Respiration / Q000379:methods*; D011650:Pulmonary Alveoli / Q000502:physiology*; D011659:Pulmonary Gas Exchange; D015656:Respiratory Mechanics / Q000502:physiology*; D016683:Supine Position; D020775:Thoracic Surgery, Video-Assisted; D013990:Tidal Volume
chemical_list: D010100:Oxygen
keywords: Alveolar recruitment; one-lung ventilation; positive end-expiratory pressure; supine position