title: Prone position in subarachnoid hemorrhage patients with acute respiratory distress syndrome: effects on cerebral tissue oxygenation and intracranial pressure.
abstract: OBJECTIVE
  To analyze the effect of prone position on cerebral perfusion pressure and brain tissue oxygen partial pressure in subarachnoid hemorrhage patients with acute respiratory distress syndrome (ARDS).
  
  
  METHODS
  Clinical study with retrospective data analysis.
  
  
  METHODS
  Neurosurgical intensive care unit of a primary level university hospital.
  
  
  METHODS
  Sixteen patients treated for intracranial aneurysm rupture with initial Hunt and Hess grade III or worse who developed ARDS within 2 wks after the bleeding.
  
  
  METHODS
  Routine neurosurgical intensive care treatment for subarachnoid hemorrhage and posthemorrhagic vasospasm including cerebral monitoring with continuous intracranial pressure and brain tissue oxygen partial pressure recordings.
  
  
  RESULTS
  Hemodynamics, arterial oxygenation, ventilatory setting, intracranial pressure, cerebral perfusion pressure, and brain tissue oxygen partial pressure in the supine as well as in the prone position were analyzed and compared. A significant increase in Pao(2) from 97.3 +/- 20.7 torr (mean +/- sd) in the supine position to 126.6 +/- 31.7 torr in the prone position was joined by a significant increase in brain tissue oxygen partial pressure from 26.8 +/- 10.9 torr to 31.6 +/- 12.2 torr (both p <.0001), whereas intracranial pressure increased from 9.3 +/- 5.2 mm Hg to 14.8 +/- 6.7 mm Hg and cerebral perfusion pressure decreased from 73.0 +/- 10.5 mm Hg to 67.7 +/- 10.7 mm Hg (both p <.0001).
  
  
  CONCLUSIONS
  The beneficial effect of prone positioning on cerebral tissue oxygenation by increasing arterial oxygenation appears to outweigh the expected adverse effect of prone positioning on cerebral tissue oxygenation by decreasing cerebral perfusion pressure in ARDS patients.
authors.affiliation: Department of Neurosurgery, University of Vienna Medical School, Vienna, Austria.
authors.forename: Andrea
authors.initials: A
authors.lastname: Reinprecht
authors.forename: Manfred
authors.initials: M
authors.lastname: Greher
authors.forename: Stefan
authors.initials: S
authors.lastname: Wolfsberger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dietrich
authors.forename: Udo M
authors.initials: UM
authors.lastname: Illievich
authors.forename: Andreas
authors.initials: A
authors.lastname: Gruber
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply*; D002545:Brain Ischemia / Q000517:prevention & control*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007427:Intracranial Pressure; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D016684:Prone Position; D012128:Respiratory Distress Syndrome / Q000209:etiology / Q000628:therapy*; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000628:therapy*
chemical_list: D010100:Oxygen