title: Qualitative comparison of carbon dioxide-induced change in cerebral near-infrared spectroscopy versus jugular venous oxygen saturation in adults with acute brain disease.
abstract: OBJECTIVE
  To compare carbon dioxide-induced changes in cerebral oxy- and deoxyhemoglobin, measured by near-infrared spectroscopy, with those changes in jugular venous oxygen saturation in adult patients with acute brain disease.
  
  
  METHODS
  A prospective study.
  
  
  METHODS
  The medical and surgical intensive care unit of a university hospital.
  
  
  METHODS
  Nine patients with head trauma (n = 4), cerebrovascular disease (n = 3), and meningitis (n = 2). A total of ten measurements were done, while PaCO2 was increased from hypocapnia toward normocapnia in the nine patients.
  
  
  METHODS
  Arterial and jugular bulb catheterization, and intracranial pressure monitoring were performed as a part of the clinical intervention. An increase in PaCO2 was obtained by inhalation of CO2 and, if necessary, by reducing the ventilator rate.
  
  
  RESULTS
  In each patient, the position of the jugular bulb catheter was ascertained by skull roentgenography. Near-infrared spectroscopic values for oxy- and deoxyhemoglobin were set at zero at the beginning of the study. An increase in PaCO2 from 29 +/- 1 (SEM) torr (3.9 +/- 0.2 kPa) to 39 +/- 2 torr (5.2 +/- 0.3 kPa) was accompanied by a significant increase in jugular venous oxygen saturation from 63 +/- 3% to 76 +/- 3%; a significant increase in oxyhemoglobin of 3.5 +/- 0.9 mumol/L (of the brain tissue); and a significant decrease in deoxyhemoglobin of 1.5 +/- 0.4 mumol/L. In nine of ten measurements, the slopes of changes in oxyhemoglobin against the slopes of change in jugular venous oxygen saturation were very similar. In one patient, oxyhemoglobin changed negligibly while jugular venous oxygen saturation increased by 20%.
  
  
  CONCLUSIONS
  Jugular venous oxygen saturation consistently demonstrates cerebrovascular responsiveness to CO2. The direction and magnitude of changes in cerebral oxyhemoglobin, measured by near-infrared spectroscopy, were similar to those changes in jugular venous oxygen saturation in most of our cases. Interpretation of a negligible change in oxyhemoglobin in one patient, despite an obvious increase in jugular venous oxygen saturation, requires further study comparing near-infrared spectroscopy with standard techniques.
authors.affiliation: Department of Critical Care Medicine, Yamaguchi University, School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Tateishi
authors.forename: T
authors.initials: T
authors.lastname: Maekawa
authors.forename: Y
authors.initials: Y
authors.lastname: Soejima
authors.forename: D
authors.initials: D
authors.lastname: Sadamitsu
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.forename: M
authors.initials: M
authors.lastname: Matsushita
authors.forename: K
authors.initials: K
authors.lastname: Nakashima
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis / Q000379:methods*; D001921:Brain / Q000098:blood supply; D001927:Brain Diseases / Q000097:blood*; D002245:Carbon Dioxide / Q000494:pharmacology*; D005069:Evaluation Studies as Topic; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007601:Jugular Veins; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000032:analysis; D011446:Prospective Studies; D013055:Spectrophotometry, Infrared
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; D002245:Carbon Dioxide; C100003:deoxyhemoglobin; D010100:Oxygen