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Background: Septic encephalopathy is believed to be a result of neuro-inflammation possibly triggered by endotoxins, such as lipopolysaccharides (LPS). Modulation of the immune system is a property of volatile anaesthetics., Objective: We aimed to investigate the systemic and cerebral inflammatory response in a LPS-induced sepsis model in rats. We compared two different sedation strategies, intravenous propofol and the volatile anaesthetic sevoflurane, with the hypothesis that the latter may attenuate neuro-inflammatory processes., Design: Laboratory rat study., Setting: Basic research laboratories at the University Hospital Zurich and University Zurich Irchel between August 2014 and June 2016., Patients: A total of 32 adult male Wistar rats., Interventions: After tracheotomy and mechanical ventilation, the anaesthetised rats were monitored before sepsis was induced by using intravenous LPS or phosphate-buffered saline as control. Rats were sedated with propofol (10 mg kg h) or sevoflurane (2 vol%) continuously for 12 h., Main Outcome Measures: Systemic inflammatory markers such as cytokine-induced neutrophil chemo-attractant protein 1, monocyte chemo-tactic protein-1 and IL-6 were determined. The same cytokines were measured in brain tissue. Cellular response in the brain was assessed by defining neutrophil accumulation with myeloperoxidase and also activation of microglia with ionised calcium-binding adaptor molecule-1 and astrocytes with glial fibrillary acidic protein. Finally, brain injury was determined., Results: Animals were haemodynamically stable in both sedation groups treated with LPS. Blood cytokine peak values were lower in the sevoflurane-LPS compared with propofol-LPS animals. In brain tissue of LPS animals, chemoattractant protein-1 was the only significantly increased cytokine (P = 0.003), however with no significance between propofol and sevoflurane. After LPS challenge, cerebral accumulation of neutrophils was observed. Microglia activation was pronounced in the hippocampus of animals treated with LPS (P = 0.006). LPS induced prominent astrogliosis (P < 0.001). There was no significant difference in microglia or astrocyte activation or apoptosis in the brain between sevoflurane and propofol., Conclusion: We have shown that systemic attenuation of inflammation by the volatile anaesthetic sevoflurane did not translate into attenuated neuro-inflammation in this LPS-induced inflammation model., Trial Registration: Animal approval No. 134/2014, Veterinäramt Zürich.

Background: Tissue hypoperfusion and inflammation in sepsis can lead to organ failure including kidney and liver. In sepsis, mortality of acute kidney injury increases by more than 50%. Which type of volume replacement should be used is still an ongoing debate. We investigated the effect of different volume strategies on inflammatory mediators in kidney and liver in an early sepsis model., Material and Methods: Adult male Wistar rats were subjected to sepsis by cecal ligation and puncture (CLP) and assigned to three fluid replenishment groups. Animals received 30mL/kg of Ringer's lactate (RL) for 2h, thereafter RL (75mL/kg), hydroxyethyl starch (HES) balanced (25mL/kg), containing malate and acetate, or HES saline (25mL/kg) for another 2h. Kidney and liver tissue was assessed for inflammation. In vitro rat endothelial cells were exposed to RL, HES balanced or HES saline for 2h, followed by stimulation with tumor necrosis factor-α (TNF-α) for another 4h. Alternatively, cells were exposed to malate, acetate or a mixture of malate and acetate, reflecting the according concentration of these substances in HES balanced. Pro-inflammatory cytokines were determined in cell supernatants., Results: Cytokine mRNA in kidney and liver was increased in CLP animals treated with HES balanced compared to RL, but not after application of HES saline. MCP-1 was 3.5fold (95% CI: 1.3, 5.6) (p<0.01) and TNF-α 2.3fold (95% CI: 1.2, 3.3) (p<0.001) upregulated in the kidney. Corresponding results were seen in liver tissue. TNF-α-stimulated endothelial cells co-exposed to RL expressed 3529±1040pg/mL MCP-1 and 59±23pg/mL CINC-1 protein. These cytokines increased by 2358pg/mL (95% CI: 1511, 3204) (p<0.001) and 29pg/ml (95% CI: 14, 45) (p<0.01) respectively when exposed to HES balanced instead. However, no further upregulation was observed with HES saline. PBS supplemented with acetate increased MCP-1 by 1325pg/mL (95% CI: 741, 1909) (p<0.001) and CINC-1 by 24pg/mL (95% CI: 9, 38) (p<0.01) compared to RL. Malate as well as HES saline did not affect cytokine expression., Conclusion: We identified HES balanced and specifically its component acetate as pro-inflammatory factor. How important this additional inflammatory burden on kidney and liver function is contributing to the sepsis-associated inflammatory burden in early sepsis needs further evaluation.

Introduction: Severe sepsis is associated with approximately 50% mortality and accounts for tremendous healthcare costs. Most patients require ventilatory support and propofol is commonly used to sedate mechanically ventilated patients. Volatile anesthetics have been shown to attenuate inflammation in a variety of different settings. We therefore hypothesized that volatile anesthetic agents may offer beneficial immunomodulatory effects during the course of long-term intra-abdominal sepsis in rats under continuous sedation and ventilation for up to 24 hours., Methods: Sham operation or cecal ligation and puncture (CLP) was performed in adult male Wistar rats followed by mechanical ventilation. Animals were sedated for 24 hours with propofol (7 to 20 mg/kg/h), sevoflurane, desflurane or isoflurane (0.7 minimal alveolar concentration each)., Results: Septic animals sedated with propofol showed a mean survival time of 12 hours, whereas >56% of all animals in the volatile groups survived 24 hours (P <0.001). After 18 hours, base excess in propofol + CLP animals (-20.6 ± 2.0) was lower than in the volatile groups (isoflurane + CLP: -11.7 ± 4.2, sevoflurane + CLP: -11.8 ± 3.5, desflurane + CLP -14.2 ± 3.7; all P <0.03). Plasma endotoxin levels reached 2-fold higher levels in propofol + CLP compared to isoflurane + CLP animals at 12 hours (P <0.001). Also blood levels of inflammatory mediators (tumor necrosis factor-α, interleukin-1β, interleukin-10, CXCL-2, interferon-γ and high mobility group protein-1) were accentuated in propofol + CLP rats compared to the isoflurane + CLP group at the same time point (P <0.04)., Conclusions: This is the first study to assess prolonged effects of sepsis and long-term application of volatile sedatives compared to propofol on survival, cardiovascular, inflammatory and end organ parameters. Results indicate that volatile anesthetics dramatically improved survival and attenuate systemic inflammation as compared to propofol. The main mechanism responsible for adverse propofol effects could be an enhanced plasma endotoxin concentration, leading to profound hypotension, which was unresponsive to fluid resuscitation.

Background: Sepsis remains a leading cause of death in intensive care units. There is growing evidence that volatile anesthetics have beneficial immunomodulatory effects on complex inflammation-mediated conditions. The authors investigated the effect of volatile anesthetics on the overall survival of mice in a sepsis model of cecal ligation and puncture (CLP)., Methods: Mice (N = 12 per treatment group) were exposed to anesthetic concentrations of desflurane, isoflurane, and sevoflurane either during induction of sepsis or when the mice showed pronounced symptoms of inflammation. Overall survival, as well as organ function and inflammation was compared with the CLP group without intervention., Results: With desflurane and sevoflurane conditioning (1.2 minimal alveolar concentration for 2 h immediately after induction of CLP) overall survival was improved to 58% and 83%, respectively, compared with 17% in the untreated CLP group. Isoflurane did not significantly affect outcome. Application of sevoflurane 24 h after sepsis induction significantly improved overall survival to 66%., Conclusions: Administration of the volatile anesthetics desflurane and sevoflurane reduced CLP-induced mortality. Anesthesia may be a critical confounder when comparing study data where different anesthesia protocols were used.

Volatile anesthetics are known to have immunomodulatory effects in conditions of organ injury. A recent study in an experimental sepsis model has shown remarkably improved survival when mice were exposed to volatile anesthetics. In the present study, we show that hexafluoroisopropanol - a water-soluble primary sevoflurane metabolite - has beneficial effects on the overall survival in a murine model of cecal ligation and puncture. Seven-day survival as well as tissue damage markers including transaminases and high mobility group box protein-1 were assessed as measures of end organ damage. In animals undergoing cecal ligation and puncture procedure hexafluoroisopropanol conditioning - but not late postconditioning 24 hours after sepsis induction - significantly increased survival rate (17% vs. 77%, p = 0.037) and attenuated secretion of organ damage markers. This study shows survival benefits by administration of the metabolite of a volatile anesthetic. If successfully translated, hexafluoroisopropanol might offer interesting therapeutic opportunities in the future treatment of abdominal sepsis.

Recent studies report promising results regarding extracorporeal magnetic separation-based blood purification for the rapid and selective removal of disease-causing compounds from whole blood. High molecular weight compounds, bacteria and cells can be eliminated from blood within minutes, hence offering novel treatment strategies for the management of intoxications and blood stream infections. However, risks associated with incomplete particle separation and the biological consequences of particles entering circulation remain largely unclear. This article discusses the promising future of magnetic separation-based purification while keeping important safety considerations in mind. [ABSTRACT FROM AUTHOR]

The use of hydroxyethyl starch (HES) in sepsis has been shown to increase mortality and acute kidney injury. However, the knowledge of the exact mechanism by which several fluids, especially starch preparations may impair end-organ function particularly in the kidney, is still missing. The aim of this study was to measure the influence of different crystalloid and colloid fluid compositions on the inflammatory response in the kidney, the liver and the lung using a rodent model of acute endotoxemia. Rats were anesthetized and mechanically ventilated. Lipopolysaccharide (5 mg/kg) was administered intravenously. After one hour crystalloids [lactate-buffered (RLac) or acetate-buffered (RAc)] were infused i.v. (30 ml/kg) in all groups. At 2 hours rats either received different crystalloids (75 ml/kg of RLac or RAc) or colloids (25 ml/kg of HES in saline or HES in RAc or gelatin in saline). Expression of messenger RNA for cytokine-induced neutrophil chemoattractant-1 (CINC-1), monocyte chemotactic protein-1 (MCP-1), necrosis factor α (TNFα) and intercellular adhesion molecule 1 (ICAM-1) was assessed in kidney, liver and lung tissue by real-time PCR after 4 hours. The use of acetate-buffered solutions was associated with a significantly higher expression of CINC-1 and TNFα mRNA in the liver, in the kidney and in the lung. Only marginal effects of gelatin and hydroxyethyl starch on mRNA expression of inflammatory mediators were observed. The study provides evidence that the type of buffering agent of different colloidal and crystalloid solutions might be a crucial factor determining the extent of early end-organ inflammatory response in sepsis. [ABSTRACT FROM AUTHOR]