title: CSF, sagittal sinus, and jugular venous pressures during desflurane or isoflurane anesthesia in dogs.
abstract: Previous studies to determine whether desflurane increases cerebrospinal fluid (CSF) pressure are inconclusive because none have included all of the following: multiple doses of desflurane, administration for at least several hours, examination at normo- and hypocapnia, a concurrent comparison group, direct measurement of both intra- and extracranial CSF pressures, and measurement of venous pressures that influence CSF pressure. The present study was designed to determine whether CSF pressure increases during 4.0 h desflurane anesthesia using a study design that included the above elements. Catheters were placed in the lateral cerebral ventricle, cisterna magna, sagittal sinus, and jugular vein of 12 dogs anesthetized with thiopental 12 mg.kg-1.h-1 and halothane 0.5 to 0.8%. Catheter pressures were measured, and the CSF-sagittal sinus pressure gradient and slope of the gradient to CSF pressure relationship were determined during control conditions. Then, 6 dogs were anesthetized with desflurane and 6 dogs were anesthetized with isoflurane, and the same values were determined for 1.0 h at each of four experimental conditions: 0.5 and 1.0 minimum alveolar concentration (MAC) during normocapnia (PaCO2 35-39 mm Hg) and 0.5 and 1.0 MAC during hypocapnia (PaCO2 20-24 mm Hg). CSF and sagittal sinus pressures, but not jugular venous pressure, increased with both desflurane and isoflurane. The greater increase of CSF pressure with 4.0 h desflurane (to 40.2 +/- 12.7 cm H2O) than with 4.0 h isoflurane (to 26.2 +/- 11.5 cm H2O) was attributable to an increase of CSF pressure that was greater during 2.0 h desflurane and normocapnia than during 2.0 h isoflurane and normocapnia, and to an increase of CSF pressure during 2.0 h desflurane and hypocapnia that was similar to that during 2.0 h isoflurane and hypocapnia. The greater increase of CSF pressure during desflurane may have resulted, in part, from increased CSF volume as indicated by a positive CSF-sagittal sinus pressure gradient (in contrast, there was little or no CSF-sagittal sinus pressure gradient during isoflurane) and a steeper slope of the gradient to CSF pressure relationship.
authors.affiliation: Department of Anesthesiology, University of Washington School of Medicine, Seattle 98195.
authors.forename: A A
authors.initials: AA
authors.lastname: Artru
authors.forename: K
authors.initials: K
authors.lastname: Powers
authors.forename: P
authors.initials: P
authors.lastname: Doepfner
mesh_terms: D000769:Anesthesia, Inhalation; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D002496:Central Venous Pressure / Q000187:drug effects*; D002552:Cerebral Ventricles / Q000502:physiology; D002555:Cerebrospinal Fluid / Q000502:physiology; D015170:Cerebrospinal Fluid Pressure / Q000187:drug effects*; D002946:Cisterna Magna / Q000502:physiology; D003392:Cranial Sinuses / Q000187:drug effects / Q000502:physiology*; D000077335:Desflurane; D004285:Dogs; D016857:Hypocapnia / Q000503:physiopathology; D007427:Intracranial Pressure / Q000187:drug effects; D007530:Isoflurane / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*; D007601:Jugular Veins / Q000187:drug effects / Q000502:physiology*; D013997:Time Factors; D014690:Venous Pressure / Q000187:drug effects*
chemical_list: D018685:Anesthetics, Inhalation; D002245:Carbon Dioxide; D000077335:Desflurane; D007530:Isoflurane