title: Prone Versus Sitting Position in Neurosurgery-Differences in Patients' Hemodynamic Management.
abstract: OBJECTIVE
  Neurosurgery in general anesthesia exposes patients to hemodynamic alterations in both the prone and the sitting position. We aimed to evaluate the hemodynamic profile during stroke volume-directed fluid administration in patients undergoing neurosurgery either in the sitting or the prone position.
  
  
  METHODS
  In 2 separate prospective trials, 30 patients in prone and 28 patients in sitting position were randomly assigned to receive either Ringer acetate (RAC) or hydroxyethyl starch (HES; 130 kDa/0.4) for optimization of stroke volume. After combining data from these 2 trials, 2-way analysis of variance was performed to compare patients' hemodynamic profile between the 2 positions and to evaluate differences between RAC and HES consumption.
  
  
  RESULTS
  To achieve comparable hemodynamics during surgery, a higher mean cumulative dose of RAC than HES was needed (679 mL ± 390 vs. 455 mL ± 253; P < 0.05). When fluid consumption was adjusted with weight, statistical difference was lost. Fluid administration did not differ between the prone and sitting position. Mean arterial pressure was lower and cardiac index and stroke volume index were higher over time in patients in the sitting position.
  
  
  CONCLUSIONS
  The sitting position does not require excess fluid treatment compared with the prone position. HES is slightly more effective than RAC in achieving comparable hemodynamics, but the difference might be explained by patient weight. With goal-directed fluid administration and moderate use of vasoactive drugs, it is possible to achieve stable hemodynamics in both positions.
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland. Electronic address: teemu.luostarinen@hus.fi.
authors.forename: Teemu
authors.initials: T
authors.lastname: Luostarinen
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Ann-Christine
authors.initials: AC
authors.lastname: Lindroos
authors.affiliation: Department of Anesthesiology, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Niiya
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Marja
authors.initials: M
authors.lastname: Silvasti-Lundell
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Alexey
authors.initials: A
authors.lastname: Schramko
authors.affiliation: Department of Neurosurgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Hernesniemi
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Randell
authors.affiliation: Division of Anesthesiology, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Tomi
authors.initials: T
authors.lastname: Niemi
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D019468:Disease Management; D005260:Female; D005440:Fluid Therapy / Q000379:methods; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods*; D056888:Patient Positioning / Q000009:adverse effects / Q000379:methods*; D016684:Prone Position / Q000502:physiology*; D011446:Prospective Studies
keywords: Fluid administration; Hemodynamics; Neurosurgery; Prone position; Sitting position