title: Alterations in cerebrospinal fluid PO(2), PCO(2), and pH measurements during and after experimental thoracic aortic cross-clamping.
abstract: In a model of aortic cross-clamping, we studied the use of a multiparameter sensor for measurement of cerebrospinal fluid (CSF) PO(2), PCO(2), and pH during and after aortic cross-clamping. The present study addressed the above-mentioned alterations and their relation according to time intervals. In 31 pigs, a sensor was introduced into the intrathecal space and epidural laser Doppler was used to measure spinal cord blood flow (SCF). By placing the aortic clamp at different levels, three different spinal cord ischemia groups were obtained (mild, moderate, and severe). CSF variables with SCF were studied for 25%, 50%, and 100% changes according to baseline level. In the clamping period, SCF decreased 71.5%, 40.0%, and 33.3% in groups 1, 2, and 3, respectively. CSF O(2) tension reached 0 in group 1, decreased 74.8% in group 2, and was 12.7% in group 3. CSF CO(2) tension increased 247.2% and 202.0% in groups 1 and 2, respectively, but slightly increased in group 3. The maximum reaction time of CSF O(2) tension was about 16.7-26.9min, although this range was 34.5-49.8min in CSF CO(2) tension. We recognized that O(2) tension reacts faster than PCO(2) and pH. It is possible for O(2) tension to be used faster than produced CO(2) in the ischemic medium, although it is known that the diffusion rate of CO(2) is much higher. Spinal cord O(2) tension monitoring is an important method to detect ischemic changes.
authors.affiliation: Department of Anesthesiology, Atatürk Training and Research Hospital for Chest Disease and Thoracic surgery, Ankara, Turkey. uluss@yahoo.com
authors.forename: Fatma
authors.initials: F
authors.lastname: Ulus
authors.forename: Anders
authors.initials: A
authors.lastname: Hellberg
authors.forename: A Tulga
authors.initials: AT
authors.lastname: Ulus
authors.forename: Sadettin
authors.initials: S
authors.lastname: Karacagil
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000601:surgery; D002245:Carbon Dioxide / Q000134:cerebrospinal fluid*; D003250:Constriction; D004195:Disease Models, Animal; D004566:Electrodes; D005260:Female; D005336:Fiber Optic Technology; D006863:Hydrogen-Ion Concentration; D017078:Laser-Doppler Flowmetry; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation; D010100:Oxygen / Q000134:cerebrospinal fluid*; D012039:Regional Blood Flow; D013116:Spinal Cord / Q000098:blood supply*; D020760:Spinal Cord Ischemia / Q000134:cerebrospinal fluid* / Q000000981:diagnostic imaging / Q000503:physiopathology; D013552:Swine; D013997:Time Factors; D014463:Ultrasonography
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen