Effects of hypertonic saline and mannitol on cortical cerebral microcirculation in a rabbit craniotomy model

Abstract

BackgroundHyperosmolar solutions have been used in neurosurgery to modify brain bulk and prevent neurological deterioration. The aim of this animal study was to compare the short-term effects of equivolemic, equiosmolar solutions of mannitol and hypertonic saline (HTS) on cerebral cortical microcirculation in a rabbit craniotomy model.MethodsRabbits (weight, 2.0–3.0 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 = 8) or 20 % mannitol (group MTL, n = 8). Microcirculation in the cerebral cortex was evaluated using sidestream dark-field (SDF) imaging before and 20 min after the end of the 15-min HTS infusion. Global hemodynamic data were recorded, and blood samples for laboratory analysis were obtained at the time of SDF image recording.ResultsNo differences in the microcirculatory parameters were observed between the groups before the use of osmotherapy. After osmotherapy, lower proportions of perfused small vessel density (P = 0.0474), perfused vessel density (P = 0.0457), and microvascular flow index (P = 0.0207) were observed in the MTL group compared with those in the HTS group.ConclusionsOur findings suggest that an equivolemic, equiosmolar HTS solution better preserves perfusion of cortical brain microcirculation compared to MTL in a rabbit craniotomy model.

Increase of cortical cerebral blood flow and further cerebral microcirculatory effects of Serelaxin in a sheep model

“…CBF was recorded at a sample rate of 40/s with a laser Doppler flowmeter (DRT4, Moor, Devon, UK). A standardized protocol was used for the SDF procedure (11,14). Briefly, to minimize artificial pressure and movement artefacts, the SDF imaging probe (MicroScan Video Microscope, MicroVision Medical, Amsterdam, The Netherlands) was attached to a custom-made flexible arm with a special adapter, allowing micromovement of the SDF probe in various axes according to the inclination of the flexible arm.…”

“…It can be assessed by laser Doppler flowmetry, which, based on the noninvasive quantification of blood flow velocity (16), allows to differentiate areal-dependent changes of microperfusion in the cortex and subcortex. In contrast, clinically relevant vessels of the microcirculation can be directly visualized by using sidestream dark-field (SDF) technique, which subsequently allows quantification of the superficial cortical microcirculation (11,14). This technique enables the quantification of the density of the perfused microvessels and, by analyzing its parameters, allows an estimated prognosis of the patient's outcome in clinical practice (26).…”

CPCGI confers neuroprotection by enhancing blood circulation and neurological function in cerebral ischemia/reperfusion rats

“…The cerebral microcirculation network refers to the blood vessel system with a diameter of <200 µm in the brain, consisting of arterioles, capillaries and venules, which can regulate cerebral blood flow, transport nutrients to the neurons and glial cells and remove waste products (12)(13)(14). The blood circulation of the large blood vessels is powered by the heart, whereas microcirculation depends upon small arteries, arterioles and capillaries to perform the function of contraction and relaxation (15).…”

A comparison of anticonvulsant efficacy and action mechanism of Mannitol vs Phenytoin in adult rat neocortical slices

“…Rather than treating seizures, hypertonic solutions are already routinely administered to patients with increased intracranial pressure ( Qureshi et al, 1999 , White et al, 2006 , Cottenceau et al, 2011 , Papangelou et al, 2013 , Todd, 2013 , Dostal et al, 2015 , Schilte et al, 2015 , Surani et al, 2015 ) so as to increase serum osmolarity up to ∼30 mOsm/L.…”