title: Accuracy of continuous jugular bulb oximetry in the intensive care unit.
abstract: OBJECTIVE
  To address the accuracy of a bedside jugular bulb oxygen saturation (SjO2) catheter monitor (Baxter-Edwards, Santa Ana, CA) versus in vitro co-oximetry measurements in the intensive care unit (ICU).
  
  
  METHODS
  By prospective protocol, we compared blood gas measurements with simultaneously recorded continuous bedside oximetric monitor values for 31 ICU patients with traumatic brain injury undergoing jugular bulb catheter monitoring. For suboptimal fiberoptic light signal quality indices, the catheter was repositioned, flushed, or both before drawing the sample for in vitro measurement. Laboratory and bedside monitor data were examined for association using the chi2 and paired t tests and a linear regression model.
  
  
  RESULTS
  We assessed 195 samples (median, 5 per patient; range, 1-14) who were monitored an average of 3.4 (range, 1-6) days. The in vivo monitor (range, 32-94%) and in vitro co-oximetry (range, 38-93%) values had acceptable correlation (y = 0.94x + 4.4, r2 = 0.80). For bedside monitor detection of jugular bulb desaturation (SjO2 < 50% for 10 min), the kappa statistic was 0.35, the sensitivity was 45 to 50%, and the specificity was 98 to 100%.
  
  
  CONCLUSIONS
  Continuous ICU SjO2 monitoring correlates significantly with in vitro values, but less so than previously described during intracranial surgery. Although sensitivity of the bedside monitor to detect confirmed desaturations remains an issue, the high specificity indicates that it is less of a concern that patients may be misdiagnosed as having desaturations resulting in unnecessary interventions. Nonetheless, suspected jugular bulb desaturation should be verified before taking therapeutic actions.
authors.affiliation: Department of Neurological Surgery, Harborview Medical Center, University of Washington, Seattle 98104, USA.
authors.forename: W M
authors.initials: WM
authors.lastname: Coplin
authors.forename: G E
authors.initials: GE
authors.lastname: O'Keefe
authors.forename: M S
authors.initials: MS
authors.lastname: Grady
authors.forename: G A
authors.initials: GA
authors.lastname: Grant
authors.forename: K S
authors.initials: KS
authors.lastname: March
authors.forename: H R
authors.initials: HR
authors.lastname: Winn
authors.forename: A M
authors.initials: AM
authors.lastname: Lam
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001930:Brain Injuries / Q000097:blood*; D002648:Child; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007601:Jugular Veins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010092:Oximetry / Q000592:standards*; D010100:Oxygen / Q000097:blood*; D019095:Point-of-Care Systems; D012680:Sensitivity and Specificity
chemical_list: D010100:Oxygen