Effects of inhalational anaesthetics in experimental allergic asthma

Abstract

SummaryWe evaluated whether isoflurane, halothane and sevoflurane attenuate the inflammatory response and improve lung morphofunction in experimental asthma. Fifty-six BALB/c mice were sensitised and challenged with ovalbumin and anaesthetised with isoflurane, halothane, sevoflurane or pentobarbital sodium for one hour. Lung mechanics and histology were evaluated. Gene expression of pro-inflammatory (tumour necrosis factor-a), pro-fibrogenic (transforming growth factor-b) and pro-angiogenic (vascular endothelial growth factor) mediators, as well as oxidative process modulators, were analysed. These modulators included nuclear factor erythroid-2 related factor 2, sirtuin, catalase and glutathione peroxidase. Isoflurane, halothane and sevoflurane reduced airway resistance, static lung elastance and atelectasis when compared with pentobarbital sodium. Sevoflurane minimised bronchoconstriction and cell infiltration, and decreased tumour necrosis factor-a, transforming growth factor-b, vascular endothelial growth factor, sirtuin, catalase and glutathione peroxidase, while increasing nuclear factor erythroid-2-related factor 2 expression. Sevoflurane down-regulated inflammatory, fibrogenic and angiogenic mediators, and modulated oxidant-antioxidant imbalance, improving lung function in this model of asthma.

The Effects of Short-Term Propofol and Dexmedetomidine on Lung Mechanics, Histology, and Biological Markers in Experimental Obesity

“…In addition, sodium THIO does not affect baseline airway tone, 26 lung mechanics, or histology. 16,26 A protective ventilatory strategy was used to discard possible biological effects associated with mechanical ventilation, which may yield confounding results. Infusion rates of sodium THIO, PRO, and DEX were based on experimental studies that reported negligible effects of these agents on hemodynamic variables in rats 6,14,16 when given for 1 hour.…”

The effects of inhalational anaesthetics on the bronchial vasculature in asthma

“…In their letter about using the infant Airtraq â for placing a adult gumelastic bougie [1], Smith and Maloney stated that the smallest available Airtraq laryngoscope permitted a good laryngeal view in an adult manikin, its narrow guiding channel allowing introduction of an adult gum-elastic bougie into the glottis for subsequent insertion of a normal adult tube. We are interested whether the authors have used this method in adult patients.…”

“…In their 'morphofunctional' model of induced allergic asthma, Burburan and colleagues report that inhalational anaesthetic agents, particularly sevoflurane, reduce inflammatory cytokine gene expression in the lungs of mice receiving intratracheal ovalbumin [1]. The authors list some limitations of their study, but we would like to add that volatile anaesthetic agents have major effects on pulmonary blood flow, which may be of relevance in the asthmatic process.…”

Volatile anaesthetic for treatment of respiratory failure from status asthmaticus requiring extracorporeal membrane oxygenation

“…They are postulated to work via direct relaxation of bronchial smooth muscle, inhibition of the release of inflammatory mediators, β-adrenergic receptor stimulation, reduction of vagal tone and vagal-mediated reflexes and antagonism of the effects of histamine and methacholine 4 5. Animal models also suggest sevoflurane functions through immune modulation to inhibit leukotriene-induced inflammation, downregulating tumour necrosis factor-α, transforming growth factor-β and vascular endothelial growth factor, increasing the Nrf2 protective antioxidant response and dampening sirt-1, catalase and glutathione peroxidase expression 6–8…”