Effects of fluid management on edema volume and midline shift in a rat model of ischemic stroke

Richard P. Paczynski, Ramesh Venkatesan, Michael N. Diringer, Yong Y. He, Chung Y. Hsu, Weili Lin

Research output: Contribution to journalArticlepeer-review

35 Scopus citations


Background and Purpose - The purpose of this study was to investigate the effects of fluid management on brain water content (BW) and midline shift (MLS) after a focal cerebral ischemic insult. Methods - A suture model was used to induce focal cerebral ischemia for 90 minutes (n=44). The rats were randomly assigned to 3 groups 2.5 hours after reperfusion: dehydration (n=24), control (n=8), or hydration (n=12). BW was obtained with the wet-dry weight method 24 hours after middle cerebral artery (MCA) occlusion. In addition, MRI were obtained (n=31) 24 hours after the onset of ischemia so that the ratio of hemispheric volumes ipsilateral (IH) and contralateral (CH) to the infarct and the extent of MLS could be obtained. Results - Across the range from moderate dehydration to intravascular volume expansion with isotonic saline, BW of the IH increased linearly as a function of change in body weight (r2=0.89), whereas few changes in relation to body weight were observed in CH, indicating a preferential effect of fluid management on the infarcted hemisphere. Furthermore, the hemispheric volume ratio (IH/CH) and MLS also increased in relation to changes in body weight. However, paradoxical increases in BW, IH/CH, and extent of MLS were observed in comparison with controls when severe dehydration was produced with high-dose mannitol. Conclusions - Changes in ischemic BW by fluid management correlated closely with changes in body weight except when high-dose mannitol was used. Mannitol, as a dehydrating agent, may be associated with bimodal effects, with a high dose aggravating ischemic BW.

Original languageEnglish
Pages (from-to)1702-1708
Number of pages7
Issue number7
StatePublished - Jul 2000


  • Brain edema
  • Cerebral ischemia
  • Magnetic resonance imaging
  • Rats


Dive into the research topics of 'Effects of fluid management on edema volume and midline shift in a rat model of ischemic stroke'. Together they form a unique fingerprint.

Cite this