title: [Effect of one lung ventilation preconditioning on oxygenation during pediatric video-assisted thoracoscopic surgery].
abstract: OBJECTIVE
  To observe the effect of one lung ventilation (OLV) preconditioning on perioperative oxygenation during pediatric video-assisted thoracoscopic surgeries (VATS).
  
  
  METHODS
  A total of 171 children aged 5 days to 11 years underwent VATS for empyema dissection and abscess excisions (n=55), mediastinal tumor resection (n=34), repair of the diaphragmatic hernia or diaphragmatic plication (n=21), pulmonary lobectomy or biopsy (n=43), or esophageal disease (n=18). Of these patients, 127 were younger than 3 years of age. A 5-Fr pediatric endobronchial blocker was used for OLV with a delivered inspired oxygen fraction (FiO(2)) of 1.0. After lateral decubitus, a sequential protocol of a 5- to 8-min OLV preconditioning and a 5-min two lung ventilation (TLV) was performed followed by OLV again before incision for VATS. In cases of a SpO(2)<95% without malposition of the blocker during OLV, a 5 cm H(2)O positive end expiratory pressure was applied; TLV was maintained for a SpO(2)<90%.
  
  
  RESULTS
  OLV provided good surgical conditions in 160 cases. Acceptable saturations were achieved in 166 cases during OLV. In 2 cases in empyema group and 3 in esophageal disease group, the ventilation protocol was converted to intermittent TLV during the operation due to hypoxemia. In esophageal disease group, the procedure and OLV duration, postoperative ventilation time and length of stay (LOS) were the longest among the groups, and the number of cases developing postoperative atelectasis was greater than that in diaphragmatic hernia and pulmonary disease groups. In empyema and esophageal disease groups, the oxygenation index (PaO(2)/FiO(2)) after total collapse of the lung in OLV and after extubation were lower than that in mediastinal tumor group (P<0.05 or 0.01).
  
  
  CONCLUSIONS
  A OLV preconditioning can maintain an acceptable oxygenation during pediatric OLV. A longer procedure and OLV duration is associated with a prolonged postoperative length of ventilation and LOS.
authors.affiliation: Department of Anesthesiology, 3Department of Cardiothoracic Surgery, Guangzhou Women and Children's Medical Center of Guangzhou Medical University, Guangzhou 510623, China. E-mail: gzetmazui@163.com.
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Jun-Yong
authors.initials: JY
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Kai-Can
authors.initials: KC
authors.lastname: Cai
mesh_terms: D001784:Blood Gas Analysis; D002648:Child; D002675:Child, Preschool; D006801:Humans; D000860:Hypoxia; D007223:Infant; D007231:Infant, Newborn; D008168:Lung; D061810:One-Lung Ventilation; D011175:Positive-Pressure Respiration; D012121:Respiration, Artificial; D020775:Thoracic Surgery, Video-Assisted