title: Inflation of the distal cuff by saline reduces the incidence of malposition of the bronchial tube during lung separation in patients receiving nitrous oxide.
abstract: BACKGROUND
  A common problem during lung separation is malposition of the double-lumen tube (DLT). It was hypothesized that inflation of the distal cuff with saline instead of air may reduce the incidence of malposition of the endobronchial tube.
  
  
  METHODS
  Fifty-two patients who were scheduled to undergo thoracic surgery with lung separation by a DLT were randomly assigned to 1 of 2 groups: the distal cuff was inflated with 2 mL of air in the air group (n = 26), whereas the distal cuff was inflated with 1.2 mL of saline in the saline group (n = 26). Anesthesia was maintained by isoflurane, 50% oxygen and nitrous oxide mixture, and incremental injection of epidural ropivacaine, 0.75%. Respiration was controlled by pressure-controlled ventilation. The peak airway pressure was maintained between 20 to 25 cmH2O. The position of the bronchial cuff was evaluated with a fiberoptic bronchoscope just after intubation and 1 and 2 hours after intubation by using a 3-point scale: 0, in exactly the same position as the previous inspection; 1, not in exactly the same position as that in the previous inspection, but there was no possibility that the tube was malpositioned; and 2, the cuff looked as if it was going to become herniated or dislodged. Signs suggesting malposition such as air leakage, high airway pressure, or inflation of the independent lung were recorded. When repositioning was required, the anesthesiologist repositioned the DLT using bronchoscopic observation or clinical signs. The endpoint of this study was the number of patients who required repositioning during surgery.
  
  
  RESULTS
  The malposition score at 1 hour and 2 hours after intubation was comparable in the 2 groups (0.6 +/- 0.6 v 0.4 +/- 0.6 and 0.5 +/- 0.8 v 0.2 +/- 0.5, mean +/- standard deviation, air group v saline group, 1 hour and 2 hours after positioning, p = 0.27 and p = 0.33, respectively). However, a significantly higher cumulative number of air-group patients required repositioning of the tube than saline-group patients (13:6, air group:saline group, p = 0.04).
  
  
  CONCLUSIONS
  Inflation of the distal cuff with saline may reduce the incidence of malpositioning of DLTs during lung separation.
authors: Department of Anesthesiology, Second Hospital Nippon Medical School, Kanagawa, Japan. manzo@nms.ac.jp <manzo@nms.ac.jp>
authors: Manzo
authors: M
authors: Suzuki
authors: Shuji
authors: S
authors: Haraguchi
authors: Akira
authors: A
authors: Kitamura
authors: Yoichi
authors: Y
authors: Shimada
authors: Atsuhiro
authors: A
authors: Sakamoto
mesh_terms: D000368:Aged; D000768:Anesthesia, General / Q000379:methods*; D018685:Anesthetics, Inhalation; D001999:Bronchoscopy; D005260:Female; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000517:prevention & control*; D007442:Intubation, Intratracheal / Q000295:instrumentation* / Q000379:methods; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide; D012965:Sodium Chloride; D019616:Thoracic Surgical Procedures / Q000379:methods*
chemical_list: D018685:Anesthetics, Inhalation; D012965:Sodium Chloride; D009609:Nitrous Oxide