title: Superior effect of hypertonic saline over mannitol to attenuate cerebral edema in a rabbit bacterial meningitis model.
abstract: OBJECTIVE
  Adjunctive therapies that reduce the cerebral edema in bacterial meningitis include osmotic agents. There is a lack of information comparing mannitol vs. hypertonic saline as an osmotic agent for adjunctive therapy of bacterial meningitis. We attempted to elucidate the impact of hypertonic saline in cerebral edema in the setting of bacterial meningitis as well as to explore potential mechanisms of action.
  
  
  METHODS
  Randomized controlled in vivo study.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  Rabbits.
  
  
  METHODS
  A rabbit model of bacterial meningitis was used comparing 3% hypertonic saline with 20% mannitol as adjunctive therapy.
  
  
  RESULTS
  Adjunctive 3% hypertonic saline treatment persistently elevated mean arterial pressure as compared with the model or ampicillin group (p < .01). Although both 20% mannitol and 3% hypertonic saline efficiently elevated serum osmolality for almost 5 hrs (p < .01), 20% mannitol lowered intracranial pressure for only a short time (<2 hrs) and did not elevate cerebral perfusion pressure. Three percent hypertonic saline treatment efficiently lowered intracranial pressure and elevated cerebral perfusion pressure for almost 5 hrs (p < .01). Furthermore, 3% hypertonic saline treatment efficiently elevated serum Na+ concentration for >5 hrs (p < .01). Three percent hypertonic saline treatment was superior to 20% mannitol in lowering leukocyte number and protein content in cerebrospinal fluid (p < .01). Three percent hypertonic saline treatment reduced water content and Evans blue incorporation in the brain (p < .01). Three percent hypertonic saline treatment inhibited aquaporin 4 expression (p < .01) and attenuated pathologic brain damage more efficiently compared with adjuvant 20% mannitol treatment (p < .01).
  
  
  CONCLUSIONS
  Adjunctive 3% hypertonic saline treatment significantly elevated mean arterial pressure, reduced intracranial pressure, greatly improved cerebral perfusion pressure, inhibited brain aquaporin 4 expression, reduced cerebral edema, and attenuated brain damage with a superior effect over 20% mannitol in a rabbit bacterial meningitis model.
authors.affiliation: Department of Pediatrics, Xiangya Hospital, [corrected] Central South University, Changsha, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Liu
authors.forename: Lian
authors.initials: L
authors.lastname: Li
authors.forename: ZiQiang
authors.initials: Z
authors.lastname: Luo
authors.forename: MingJie
authors.initials: M
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: She
authors.forename: Xiaohe
authors.initials: X
authors.lastname: Yu
authors.forename: XiaoDan
authors.initials: X
authors.lastname: Deng
authors.forename: FuRong
authors.initials: F
authors.lastname: Huang
authors.forename: LiHong
authors.initials: L
authors.lastname: Shang
authors.forename: ChangE
authors.initials: C
authors.lastname: Jian
authors.forename: GengZhong
authors.initials: G
authors.lastname: Ji
authors.forename: ShaoJie
authors.initials: S
authors.lastname: Yue
mesh_terms: D000667:Ampicillin / Q000627:therapeutic use; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001929:Brain Edema / Q000382:microbiology* / Q000517:prevention & control*; D017024:Chemotherapy, Adjuvant; D004195:Disease Models, Animal; D004234:Diuretics, Osmotic / Q000627:therapeutic use*; D008353:Mannitol / Q000627:therapeutic use*; D020814:Meningitis, Escherichia coli / Q000150:complications* / Q000628:therapy; D011817:Rabbits; D012462:Saline Solution, Hypertonic / Q000627:therapeutic use*
chemical_list: D000900:Anti-Bacterial Agents; D004234:Diuretics, Osmotic; D012462:Saline Solution, Hypertonic; D008353:Mannitol; D000667:Ampicillin