title: [Changes in cerebral blood flow velocity in supine and sitting position in patients with aneurysmal subarachnoid hemorrhage].
abstract: BACKGROUND
  Early mobilization in intensive care units (ICU) provides respiratory, neurological and cardiovascular benefits in hospitalized patients. However, the orthostatic effects of changing from a supine to a sitting position may interfere with cerebral hemodynamics of patients with aneurysmal subarachnoid hemorrhage (aSAH).
  
  
  OBJECTIVE
  To describe the changes in mean cerebral blood flow velocity (MCBFV) in supine and sitting position, in adult patients with aSAH, with asymptomatic vasospasm (AVS) or without vasospasm (VS) at a neurosurgical ICU.
  
  
  METHODS
  Descriptive case series study in 21 patients with aSAH, both with and without VS. They were positioned in a supine 30° position and then seated at the edge of bed for six minutes. MCBFV was measured by transcranial Doppler (TCD), and hemodynamic variables in both positions were registered. After this basal assessment and for 21 days after the episode of SAH, patients were seated once a day and signs of VS were recorded.
  
  
  RESULTS
  No significant changes in MCBFV or hemodynamic variables were detected during position changes, except for an increase in heart rate in the sitting position. No patient with AVS at the onset, had symptomatic VS during the 21 days of follow up when patients were seated. Among patients with a normal MCBFV at baseline, five patients (24%) had VS at a mean of three days after the first time that they were seated on the edge of bed.
  
  
  CONCLUSIONS
  Sitting patients at the edge of the bed is a safe mobilization alternative for patients who suffered aSAH who did not have VS or had AVS.
authors.forename: Catalina
authors.initials: C
authors.lastname: Merino
authors.forename: Pía
authors.initials: P
authors.lastname: Heap
authors.forename: Valentina
authors.initials: V
authors.lastname: Vergara
authors.forename: Alonso
authors.initials: A
authors.lastname: Yáñez
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Rivera
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D056888:Patient Positioning / Q000009:adverse effects / Q000379:methods*; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016683:Supine Position / Q000502:physiology*; D017585:Ultrasonography, Doppler, Transcranial; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*