Search results for "Methyl Ether"
showing 10 items of 40 documents
Volatile Anesthetics Influence Blood-Brain Barrier Integrity by Modulation of Tight Junction Protein Expression in Traumatic Brain Injury
2012
Disruption of the blood-brain barrier (BBB) results in cerebral edema formation, which is a major cause for high mortality after traumatic brain injury (TBI). As anesthetic care is mandatory in patients suffering from severe TBI it may be important to elucidate the effect of different anesthetics on cerebral edema formation. Tight junction proteins (TJ) such as zonula occludens-1 (ZO-1) and claudin-5 (cl5) play a central role for BBB stability. First, the influence of the volatile anesthetics sevoflurane and isoflurane on in-vitro BBB integrity was investigated by quantification of the electrical resistance (TEER) in murine brain endothelial monolayers and neurovascular co-cultures of the B…
Cerebral haemodynamic changes during propofol-remifentanil or sevoflurane anaesthesia: transcranial Doppler study under bispectral index monitoring
2006
Background. Sevoflurane or propofol–remifentanil-based anaesthetic regimens represent modern techniques for neurosurgical anaesthesia. Nevertheless, there are potential differences related to their activity on the cerebrovascular system. The magnitude of such difference is not completely known. Methods. In total 40 patients, treated for spinal or maxillo-facial disorders, were randomly allocated to either i.v. propofol–remifentanil or inhalational sevoflurane anaesthesia. Transcranial Doppler was used to assess changes in cerebral blood flow velocity, carbon dioxide reactivity, cerebral autoregulation and the bispectral index to assess the depth of anaesthesia. Results. Time-averaged mean f…
Hydrophilic membranes based on poly(vinyl methyl ether-crosslinked-polystyrene) semi-interpenetrating networks
1991
Microporous membranes were prepared from poly(vinyl methyl ether - crosslinked-polystyrene) (PVME-cross-PS) semi-IPN's by extraction of poly(vinyl methyl ether) (PVME) with water. Membrane morphology and properties are fixed during the process of swelling, phase separation, PVME extraction and vitrification which occurs upon immersing the samples in water. The membranes are characterized by swelling (water uptake), the relative amounts of free and bound water, and their permselectivity towards KCI solution.
Sevoflurane Impairs Cerebral Blood Flow Autoregulation in Rats: Reversal by Nonselective Nitric Oxide Synthase Inhibition
2005
UNLABELLED In this study, we investigated the effects of 1.0 and 2.0 minimum alveolar anesthetic concentration (MAC) sevoflurane on cerebral blood flow (CBF) autoregulation before and after nonselective inhibition of nitric oxide (NO) synthase in rats. Rats were randomly assigned as follows: Group 1 (n = 8): 1.0 MAC sevoflurane; Groups 2 and 3 (n = 8 per group): 2.0 MAC sevoflurane. Assessment of autoregulation within a mean arterial blood pressure range of 140-60 mm Hg was performed by graded hemorrhage before and after administration of l-arginine methyl ester (l-NAME, 30 mg/kg IV, Groups 1 and 2) or during hypocapnia (Group 3). In 10 additional animals, brain tissue NO(2)(-) concentratio…
Aliphatic polycarbonates based on carbon dioxide, furfuryl glycidyl ether, and glycidyl methyl ether: reversible functionalization and cross-linking.
2014
Well-defined poly((furfuryl glycidyl ether)-co-(glycidyl methyl ether) carbonate) (P((FGE-co-GME)C)) copolymers with varying furfuryl glycidyl ether (FGE) content in the range of 26% to 100% are prepared directly from CO2 and the respective epoxides in a solvent-free synthesis. All materials are characterized by size-exclusion chromatography (SEC), (1)H NMR spectroscopy, and differential scanning calorimetry (DSC). The furfuryl-functional samples exhibit monomodal molecular weight distributions with Mw/Mn in the range of 1.16 to 1.43 and molecular weights (Mn) between 2300 and 4300 g mol(-1). Thermal properties reflect the amorphous structure of the polymers. Both post-functionalization and…
Sevoflurane-induced reduction of bispectral index does not affect human cerebral microcirculation
2015
Inhalational or intravenous anesthetics for craniotomies? Pro inhalational.
2006
In neurosurgery, anesthesiologists and surgeons focus on the same target - the brain. The nature of anesthetics is to interact with brain physiology, leading to favorable and adverse effects. Research in neuroanesthesia over the last three decades has been dedicated to identifying the optimal anesthetic agent to maintain coupling between cerebral blood flow and metabolism, keep cerebrovascular autoregulation intact, and not increase cerebral blood volume and intracranial pressure.Sevoflurane is less vasoactive than halothane, enflurane, isoflurane, or desflurane. The context sensitive half-life is short and similar to that of desflurane, which translates into fast on and offset. Compared wi…
Isoflurane is associated with a similar incidence of emergence agitation/delirium as sevoflurane in young children ? a randomized controlled study
2006
Summary Background: Children may be agitated or even delirious especially when recovering from general anesthesia using volatile anesthetics. Many trials have focused on the newer agents sevoflurane and desflurane but for the widely used isoflurane little is known about its potential to generate agitation. We investigated the emergence characteristics of small children after sevoflurane or isoflurane with caudal anesthesia for postoperative pain control. Methods: After institutional approval and parental consent, anesthesia was randomly performed with sevoflurane (n = 30) or isoflurane (n = 29) in children at the age of 3.8 ± 1.8 years during surgical interventions on the lower part of th…
Economic Considerations of the Use of New Anesthetics
1998
UNLABELLED: Cost control in anesthesia is no longer an option; it is a necessity. New anesthetics have entered the market, but economic differences in comparison to standard anesthetic regimens are not exactly known. Eighty patients undergoing either subtotal thyroidectomy or laparoscopic cholecystectomy were randomly divided into four groups, with 20 patients in each group. Group 1 received propofol 1%/sufentanil, Group 2 received desflurane/sufentanil, Group 3 received sevoflurane/sufentanil, and Group 4 received isoflurane/sufentanil (standard anesthesia) for anesthesia. A fresh gas flow of 1.5-2 L/min and 60% N2O in oxygen was used for maintenance of anesthesia, and atracurium was given…