Hyperosmolar solutions have been used in neurosurgery to modify brain bulk. The aim of this animal study was to compare the short-term effects of equivolemic, equiosmolar solutions of hypertonic saline (HTS) and sodium lactate (HTL) on cerebral cortical microcirculation and brain tissue oxygenation in a rabbit craniotomy model.
Rabbits (weight, 1.5 to 2.0 kg) were anesthetized, ventilated mechanically, and subjected to a craniotomy. The animals were allocated randomly to receive a 3.75 mL/kg intravenous infusion of either 3.2% HTS (group HTS, n=9), half-molar sodium lactate (group HTL, n=10), or normal saline (group C, n=9). Brain tissue partial pressure of oxygen (PbtO2) and microcirculation in the cerebral cortex using sidestream dark-field imaging were evaluated before, 20 and 40 minutes after 15 minutes of hyperosmolar solution infusion. Global hemodynamic data were recorded, and blood samples for laboratory analysis were obtained at the time of sidestream dark-field image recording.
No differences in the microcirculatory parameters were observed between the groups before and after the use of osmotherapy. Brain tissue oxygen deteriorated over time in groups C and HTL, this deterioration was not significant in the group HTS.
Our findings suggest that equivolemic, equiosmolar HTS and HTL solutions equally preserve perfusion of cortical brain microcirculation in a rabbit craniotomy model. The use of HTS was better in preventing the worsening of brain tissue oxygen tension.
Departments of *Anesthesia and Intensive Care Medicine
‡Clinical Biochemistry, Charles University, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove, Hradec Kralove
†Department of Military Surgery, Faculty of Military Health Sciences, Hradec Kralove, University of Defence, Brno, Czech Republic
V.D. conceived the study, performed the animal experiments, and prepared the manuscript. P.D. participated in the experimental design, performed the statistical analysis, and finalized the manuscript. V.D. Jr, participated in the animal experiments, performed the SDF analysis and facilitated manuscript drafting. J.P. participated in the study design and facilitated manuscript drafting. J.S., J.K., A.T., and V.R. participated in the animal experiments and facilitated manuscript drafting.
Research funding was provided by the Project of Ministry of Defence of the Czech Republic: A Long-term Organization Development Plan 1011.
The authors have no funding or conflicts of interest to disclose.
Address correspondence to: Pavel Dostal, MD, PhD, Department of Anesthesia and Intensive Care Medicine, University Hospital Hradec, Kralove, Sokolska 581, Hradec Kralove, 500 05 Czech Republic (e-mail: email@example.com).
Received October 19, 2016
Accepted February 22, 2017