Protective effects of thoracic epidural anesthesia on hypoxia-induced acute lung injury in rabbits

Impact of early thoracic epidural analgesia in patients with severe acute pancreatitis

OBJECTIVE

This study was designed to assess the impact of thoracic epidural analgesia (TEA) in patients with severe acute pancreatitis (SAP).

METHODS

This is a single-centre retrospective study. In this study, the outcomes of SAP patients were compared between patients received TEA (TEA group) and without TEA (NTEA group). Early TEA was defined as TEA performed within 48 hours after onset. The main outcome was the mortality at 30 days after ICU admission, and secondary outcomes included the incidence of acute respiratory distress syndrome (ARDS), the acute renal injury (AKI) and sepsis, the hospital stay and hospitalization expenses.

RESULTS

The mortality of SAP patients in TEA versus NTEA was 8.0% and 13.3% (p = .1520). Multivariate regression analysis showed significant difference in mortality between the TEA and NTEA groups (OR, 0.387; 95% CI, 0.168-0.892; p = .026). The incidence of ARDS in TEA versus NTEA was 46.0% and 62.4% (p = .0044); the proportion of patients requiring invasive ventilator assisted ventilation in TEA, and NTEA was 22.6% and 39.2% (p = .0016). The incidence of AKI in TEA versus NTEA was 27.7% and 45.3% (p = .0044); the proportion of patients needing for continuous renal replacement therapy (CRRT) in TEA and NTEA was 48.2% and 74.0% (p < .0001). The mortality of SAP patients in early TEA versus NTEA was 4.8% and 15.3% (p = .0263).

CONCLUSIONS

TEA was associated with low incidence of ARDS and AKI in patients with SAP. Early TEA may benefit mortality in SAP patients and is a possible protective factor for the mortality of SAP patients.

GLP-1 Analogue Liraglutide Enhances SP-A Expression in LPS-Induced Acute Lung Injury through the TTF-1 Signaling Pathway

The reduction of pulmonary surfactant (PS) is essential for decreased pulmonary compliance and edema in acute lung injury (ALI). Thyroid transcription factor-1 (TTF-1) plays a major role in the regulation of surfactant protein-A (SP-A), the most abundant protein component of PS. Simultaneously, the glucagon-like peptide-1 (GLP-1) analogue can enhance SP-A expression in the lung. However, the underlying mechanism is still unknown. The purpose of this study was to explore whether liraglutide, a GLP-1 analogue, upregulates SP-A expression through the TTF-1 signaling pathway in ALI. In vivo, a murine model of ALI was induced by lipopolysaccharide (LPS). Pulmonary inflammation, edema, insulin level, ultrastructural changes in type II alveolar epithelial (ATII) cells, and SP-A and TTF-1 expression were analyzed. In vitro, rat ATII cells were obtained. SP-A and TTF-1 expression in cells was measured. ShRNA-TTF-1 transfection was performed to knock down TTF-1 expression. Our data showed that LPS-induced lung injury and increase in insulin level, and LPS-induced reduction of SP-A and TTF-1 expression in both the lung and cells, were significantly compromised by liraglutide. Furthermore, we also found that these effects of liraglutide were markedly blunted by shRNA-TTF-1. Taken together, our findings suggest that liraglutide enhances SP-A expression in ATII cells and attenuates pulmonary inflammation in LPS-induced ALI, most likely through the TTF-1 signaling pathway.

Sub-Acute Toxicity Study of Graphene Oxide in the Sprague-Dawley Rat

Graphene oxide (GO) is an oxidized derivative of graphene used in biotechnology and medicine. The safety of GO is uncertain, so we evaluated its toxicity in male rats. Rat tail veins were injected with 2.5, 5, or 10 mg/kg GO for seven days and behavioral patterns, pathology, and tissue morphology were assessed. Data show that behaviors were not altered according to an open field test and a functional observational battery test, but histopathological analysis indicated that GO caused inflammation of the lung, liver, and spleen. GO also reduced cholesterol, high density lipoprotein (HDL), and low density lipoprotein (LDL). No other organs were modified. Thus, high concentrations of GO are toxic for the lung, liver, and spleen, but the mechanism by which this occurs requires more study.