title: Intra-Operative Fluid Management in Adult Neurosurgical Patients Undergoing Intracranial Tumour Surgery: Randomised Control Trial Comparing Pulse Pressure Variance (PPV) and Central Venous Pressure (CVP).
abstract: BACKGROUND
  Fluid management in neurosurgery presents specific challenges to the anaesthesiologist. Dynamic para-meters like Pulse Pressure Variation (PPV) have been used successfully to guide fluid management.
  
  
  OBJECTIVE
  To compare PPV against Central Venous Pressure (CVP) in neurosurgical patients to assess hemodynamic stability and perfusion status.
  
  
  METHODS
  This was a single centre prospective randomised control trial at a tertiary care centre. A total of 60 patients undergoing intracranial tumour excision in supine and lateral positions were randomised to two groups (Group 1, CVP n=30), (Group 2, PPV n=30). Intra-operative fluid management was titrated to maintain baseline CVP in Group 1(5-10cm of water) and in Group 2 fluids were given to maintain PPV less than 13%. Acid base status, vital signs and blood loss were monitored.
  
  
  RESULTS
  Although intra-operative hypotension and acid base changes were comparable between the groups, the patients in the CVP group had more episodes of hypotension requiring fluid boluses in the first 24 hours post surgery. {CVP group median (25, 75) 2400ml (1850, 3110) versus PPV group 2100ml (1350, 2200) p=0.03} The patients in the PPV group received more fluids than the CVP group which was clinically significant. {2250 ml (1500, 3000) versus 1500ml (1200, 2000) median (25, 75) (p=0.002)}. The blood loss was not significantly different between the groups The median blood loss in the CVP group was 600ml and in the PPV group was 850 ml; p value 0.09.
  
  
  CONCLUSIONS
  PPV can be used as a reliable index to guide fluid management in neurosurgical patients undergoing tumour excision surgery in supine and lateral positions and can effectively augment CVP as a guide to fluid management. Patients in PPV group had better hemodynamic stability and less post operative fluid requirement.
authors.affiliation: Registrar, Department of Anaesthesia, Christian Medical College , Vellore, India .
authors.forename: Shalini Cynthia
authors.initials: SC
authors.lastname: Sundaram
authors.affiliation: Assistant Professor, Department of Anaesthesia, Christian Medical College , Vellore, India .
authors.forename: Serina Ruth
authors.initials: SR
authors.lastname: Salins
authors.affiliation: Consultant Anaesthetist, Department of Anaesthesia, Kovai Medical Center And Hospital , Coimbatore, India .
authors.forename: Amar Nandha
authors.initials: AN
authors.lastname: Kumar
authors.affiliation: Professor Emeritus, Department of Anaesthesia, Christian Medical College , Vellore, India .
authors.forename: Grace
authors.initials: G
authors.lastname: Korula
keywords: Cerebral; Dynamic indices; Goal directed fluid therapy; Monitoring