Fast green FCF prevents postoperative cognitive dysfunction via the downregulation of the P2X4 receptor in mice.

Postoperative cognitive dysfunction (POCD) is a decline in cognitive function affecting the mental health of aged patients after surgery. The pathological mechanisms underlying POCD have not yet been clarified. The overexpression of the P2X4 receptor in the central nervous system (CNS) was reported to be associated with the onset of POCD. Fast green FCF (FGF), a widely used food dye, could decrease the expression of the P2X4 receptor in the CNS. This study aimed to explore whether FGF could prevent POCD via the down-regulation of CNS P2X4 receptor. Exploratory laparotomy under the anesthesia of fentanyl and droperidol was carried to establish an animal model of POCD in 10-12-months-olds mice. FGF significantly attenuated cognitive impairments and down-regulated the expression of the P2X4 receptor induced by surgery in mice. Moreover, the blockade of CNS P2X4 receptor by intrahippocampal injection of 5-BDBD induced cognitive-enhancing effects on POCD mice. In addition, the effects of FGF were abolished by ivermectin, which is a positive allosteric modulator of the P2X4 receptor. FGF also inhibited M1 polarization of microglia cells, decreased the phosphorylation of nuclear factor-κB (NF-κB), and reduced the production of pro-inflammatory cytokines. These results suggested that FGF produced anti-POCD cognitive-enhancing effects via down-regulation of the P2X4 receptor-associated neuroinflammation, providing a support that FGF might be a potential treatment for POCD.

[Application of modified percutaneous rotating dilative tracheostomy with fiberoptic bronchoscope in critical patients of ICU: a control study for four kinds of tracheostomy].

OBJECTIVE: To investigate the clinical application of modified percutaneous rotating dilative tracheostomy with fiberoptic bronchoscope (MPRDT-FOB) in critical patients of intensive care unit (ICU) by comparing it with percutaneous dilative tracheostomy (PDT), modified percutaneous dilative tracheostomy (MPDT), and percutaneous dilative tracheostomy with fiberoptic bronchoscope (PDT-FOB). METHODS: A prospective control study was conducted. 240 critical patients underwent tracheotomy admitted to ICU of Mudanjiang Medical University Hongqi Hospital from February 2011 to November 2016 were enrolled, and they were randomly divided into four groups with 60 patients in each group. The patients in PDT group received traditional Portex method for tracheotomy. The patients in MPDT group received PDT method first, in the process of puncture and expansion, the trachea catheter was always retained in situ, and then retreated to the puncture site about 16-18 cm from incisor after withdrawal of the dilator. The patients in PDT-FOB group received PDT with fiberoptic bronchoscope. The patients in MPRDT-FOB group received PDT-FOB combined with MPDT, in bronchoscope expansion incision, and was replaced with rotary expander to the anterior wall of the trachea. The duration of operation, the size of incision, blood loss during operation, and the rate of disposable success, as well as the incidence of perioperative and long-term complications among four kinds of tracheostomy were compared. RESULTS: Compared with PDT and PDT-FOB, the duration of operation in MPDT and MPRDT-FOB was significantly shortened (minutes: 6.57±3.59, 7.09±2.55 vs. 12.20±2.01, 10.13±2.37), the size of incision was significantly diminished (cm: 1.20±1.00, 1.20±0.90 vs. 1.59±1.18, 1.32±1.24), and the amount of blood loss during operation was significantly decreased (mL: 6.81±2.19, 6.60±1.99 vs. 10.28±3.68, 8.11±2.96, all P < 0.05). There were no significant differences in above parameters between MPDT and MPRDT-FOB, but those in MPRDT-FOB were better than MPDT, and the rate of disposable success in MPRDT-FOB was significantly higher than that of MPDT [100.00% (60/60) vs. 91.67% (55/60), P < 0.05]. The perioperative complications of four methods, such as postoperative bleeding, arrhythmia and bronchospasm, were recorded, but the incidences in MPRDT-FOB were lower than those of PDT, MPDT, and PDT-FOB. Patients in PDT and MPDT had more posterior wall injury or perforation, aspiration and intubation difficulties, while PDT-FOB and MPRDT-FOB had no above complications. The most common long-term complication of PDT was tracheal fistula, and the incidence was significantly higher than that of MPDT (25.00% vs. 13.33%, P < 0.05). However, there was no tracheoesophageal fistula report in PDT-FOB and MPRDT-FOB. Incision swallowing dysfunction, excessive phlegm, incision infection, tube collapse, airway stenosis, delayed healing, granulation or scar, and other complications of the four methods group were rare, and the differences was not statistically significant (all P > 0.05). CONCLUSIONS: It was proved that MPRDT-FOB to be a time-saving, easy-to-operate way with few complication. Moreover, it was able to deal with the problems of the tracheal wall injury or perforation, tracheoesophageal fistula, and hypoxia. Hence, it was better than PDT, MPDT, and PDT-FOB.