title: Cerebral oxygenation monitoring of patients during arthroscopic shoulder surgery in the sitting position.
abstract: BACKGROUND
  Cerebral hypotension and desaturation can occur during shoulder surgery in the seated position. We evaluated the correlation of cerebral oxygen saturation (rSO(2)) using near infra-red spectroscopy (NIRS) and mean arterial pressures (MAP) (at the levels of the brain and heart).
  
  
  METHODS
  Fifty patients, scheduled for the arthroscopic shoulder surgery in the seated position, were enrolled to monitor the rSO(2), bispectral Index (BIS), and MAPs at the levels of the brain and heart. The values of each parameter were collected at 5 min after intubation, immediately after placing the patient in the sitting position, 5 min after the patient was seated, immediately after the surgical incision, and every 30 min after incision.
  
  
  RESULTS
  A correlation between the cerebral rSO(2) and the MAP at the level of brain were statistically significant. Cerebral rSO(2) and MAP after a change of posture from supine to sitting position were significantly decreased, compared to the baseline value.
  
  
  CONCLUSIONS
  Monitoring cerebral rSO(2) and MAP at the level of brain can be helpful to detect the possibility of cerebral deoxygenation earlier.
authors.affiliation: Department of Orthopedic Surgery, Ulsan University Hospital, College of Medicine, University of Ulsan, Ulsan, Korea.
authors.forename: Sang-Hun
authors.initials: SH
authors.lastname: Ko
authors.forename: Young Woo
authors.initials: YW
authors.lastname: Cho
authors.forename: Se Hun
authors.initials: SH
authors.lastname: Park
authors.forename: Jin-Gyu
authors.initials: JG
authors.lastname: Jeong
authors.forename: Seung-Myeong
authors.initials: SM
authors.lastname: Shin
authors.forename: Gun
authors.initials: G
authors.lastname: Kang
keywords: Bispectral index; MAP; Shoulder surgery; Sitting position; rSO2