title: The effects of fluid balance and colloid administration on outcomes in patients with aneurysmal subarachnoid hemorrhage: a propensity score-matched analysis.
abstract: BACKGROUND
  Delayed ischemic neurological deficit (DIND) following aneurysmal subarachnoid hemorrhage (SAH) remains a significant cause of mortality and disability. The administration of colloids and the induction of a positive fluid balance during the vasospasm risk period remain controversial. Here, we compared DIND and outcomes among propensity score-matched cohorts who did and did not receive colloids and also tested the effect of a positive fluid balance on these endpoints.
  
  
  METHODS
  Exploratory analysis was performed on 413 patients enrolled in CONSCIOUS-1, a prospective randomized trial of clazosentan for the prevention of angiographic vasospasm. Propensity score matching was performed on the basis of age, gender, pre-existing heart conditions, hypertension, nicotine use, World Federation of Neurosurgical Societies scores, aneurysm location, clazosentan treatment, subarachnoid clot burden, and severity of angiographic vasospasm. Inferential statistics were used for group-wise comparisons.
  
  
  RESULTS
  One hundred twenty-three subjects were matched (41 received colloids, whereas 82 did not). The covariate balance and propensity score distributions were acceptable. There was no difference between the groups with respect to DIND (17 vs. 22%; p = 0.64) or the presence (48 vs. 51%; p = 0.71) or volume of delayed infarcts (volume >7.5 cm3; 62 vs. 48%; p = 0.41). Similarly, no differences were found on multivariate analysis between patients who did and did not have a positive fluid balance, although patients with severe angiographic vasospasm had more delayed infarcts with a negative fluid balance (p = 0.01). Among all subjects, the administration of colloids and a positive fluid balance were associated with worse outcomes on the NIHSS (p = 0.04) and modified Rankin (p = 0.02) scales, respectively.
  
  
  CONCLUSIONS
  Colloid administration and induction of a positive fluid balance during the vasospasm risk period may be associated with poor outcomes in specific patient groups. Patient selection is of utmost importance when managing the fluid status of patients with aneurysmal SAH.
authors.affiliation: Division of Neurosurgery, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada, george.m.ibrahim@gmail.com.
authors.forename: George M
authors.initials: GM
authors.lastname: Ibrahim
authors.forename: R Loch
authors.initials: RL
authors.lastname: Macdonald
mesh_terms: D000368:Aged; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control; D003102:Colloids / Q000627:therapeutic use*; D003422:Critical Care / Q000379:methods; D004146:Dioxanes / Q000008:administration & dosage*; D004311:Double-Blind Method; D065130:Endothelin A Receptor Antagonists; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D011446:Prospective Studies; D011725:Pyridines / Q000008:administration & dosage*; D011743:Pyrimidines / Q000008:administration & dosage*; D011859:Radiography; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000628:therapy; D013449:Sulfonamides / Q000008:administration & dosage*; D013777:Tetrazoles / Q000008:administration & dosage*; D014665:Vasodilator Agents / Q000008:administration & dosage*; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D014882:Water-Electrolyte Balance / Q000502:physiology*
chemical_list: D003102:Colloids; D004146:Dioxanes; D065130:Endothelin A Receptor Antagonists; D011725:Pyridines; D011743:Pyrimidines; D013449:Sulfonamides; D013777:Tetrazoles; D014665:Vasodilator Agents; C109641:clazosentan