Response of Chinese Anesthesiologists to the COVID-19 Outbreak.

The coronavirus disease 2019, named COVID-19 officially by the World Health Organization (Geneva, Switzerland) on February 12, 2020, has spread at unprecedented speed. After the first outbreak in Wuhan, China, Chinese anesthesiologists encountered increasing numbers of infected patients since December 2019. Because the main route of transmission is via respiratory droplets and close contact, anesthesia providers are at a high risk when responding to the devastating mass emergency. So far, actions have been taken including but not limited to nationwide actions and online education regarding special procedures of airway management, oxygen therapy, ventilation support, hemodynamic management, sedation, and analgesia. As the epidemic situation has lasted for months (thus far), special platforms have also been set up to provide free mental health care to all anesthesia providers participating in acute and critical caring for COVID-19 patients. The current article documents the actions taken, lesson learned, and future work needed.

NLRP3 inflammasome as a potential treatment in ischemic stroke concomitant with diabetes.

The NLRP3 (nucleotide-binding oligomerization domain-like receptor [NLR] family pyrin domain-containing 3) inflammasome is a member of the NLR family of innate immune cell sensors. These are crucial regulators of cytokine secretions, which promote ischemic cell death and insulin resistance. This review summarizes recent progress regarding the NLRP3 inflammasome as a potential treatment for ischemic stroke in patients with diabetes, two complicated diseases that often occur together. Stroke worsens glucose metabolism abnormalities, and the outcomes after stroke are more serious for diabetic patients compared with those without diabetes. Inflammation contributes to organ injury after ischemic stroke and diabetes. Recent research has focused on inhibiting the activation of inflammasomes and thus reducing the maturation of proinflammatory cytokines such as interleukin (IL)-1ß and IL-18. Studies suggest that inhibition of NLRP3 prevents or alleviates both ischemic stroke and diabetes. Targeting against the assembly and activity of the NLRP3 inflammasome is a potential and novel therapy for inflammasome-associated diseases, including ischemic stroke concomitant with diabetes.

Inhibition of NLRP3 Inflammasome Ameliorates Cerebral Ischemia-Reperfusion Injury in Diabetic Mice.

Sustained activation of NLRP3 inflammasome is closely related to diabetes and stroke. However, it is unknown whether NLRP3 inflammasome plays an essential role in stroke in diabetes. We aim to investigate the effect and the potential mechanism of NLRP3 inflammasome in diabetic mice with cerebral ischemia-reperfusion injury. A type 2 diabetic mouse model was induced by a high-fat diet and streptozotocin (STZ). Diabetic mice received MCC950 (the specific molecule NLRP3 inhibitor) or vehicle 60 minutes before the middle cerebral artery occlusion (MCAO) and reperfusion. MCC950 reduced the neurological deficit score of 24 h after cerebral ischemia reperfusion and improved the 28-day survival rate of cerebral ischemia-reperfusion injury in diabetic mice. Furthermore, we found that the mRNA transcription levels of NLRP3, IL-1ß, and caspase-1 in the core ischemic area were remarkably amplified in diabetic mice with cerebral ischemia-reperfusion injury, whereas this phenomenon was obviously attenuated by MCC950 pretreatment. In conclusion, the NLRP3 inflammasome was involved in the complex diseases of diabetic stroke. MCC950, the NLRP3 specific inhibitor, ameliorated diabetic mice with cerebral ischemia-reperfusion injury and improved the 28-day survival rate during the recovery stage of ischemic stroke.

Waste anesthetic gas exposure and strategies for solution.

As inhaled anesthetics are widely used, medical staff have inevitably suffered from exposure to anesthetic waste gases (WAGs). Whether chronic exposure to WAGs has an impact on the health of medical staff has long been a common concern, but conclusions are not consistent. Many measures and equipment have been proposed to reduce the concentration of WAGs as far as possible. This review aims to dissect the current exposure to WAGs and its influence on medical staff in the workplace and the environment, and summarize strategies to reduce WAGs.

[Flavanoids Extracted from Onion Inhibited Activation of Microglia and Release of Proinflammatory Factors around the Hematoma in ICH Model Rats].

OBJECTIVE: To study flavanoids extracted from onion (FEO) on the number of activated microglia and the release of proinflammatory factors in intracerebral hemorrhage (ICH) model rat at different time points, and to explore its possible mechanism for treating ICH. METHODS: Totally 100 Wistar rats were used for preparing ICH model, and ICH model was successfully established in 90 of them. The 90 rats were randomly divided into the sham-operation group (n =10) , the ICH group (n =40) , the FEO group (n =40). Totally 100 [L autoblood was injected from fixed position to rats in the ICH group and the FEO group during modeling. Meanwhile, FEO at 0. 2 mL/10 g was given to rats in the FEO group, twice daily. No drug intervention was given to rats in the ICH group and the sham-operation group. Each group was further sub-divided into 5 sub-groups according to different time points such as 6, 24, 48, 72 h, and 7 days. There were 8 rats in each sub-group of the ICH group and the FEO group, 10 groups in total. There were 2 rats in each subgroup of the sham-operation group, 5 groups in total. Neurological functions at different time points were observed by Garcia JH. The injury degree of brain tissue was observed at dif- ferent time points using HE staining. Activated microglia around hematoma were observed at different time points after ICH by using immunohistochemical staining. Expressions of TNF-α and IL-1 ß at different time points after ICH was detected using ELISA. RESULTS: In the ICH group, degenerated and necrotic zone occurred around hematoma after injecting autoblood, cells were untidily arranged with irregular nucleus, partial nucleus were shrunken with lamellar interstitial edema of the medulla. As time went by, degenerated and necrotic zone was dilated; vacant zone occurred around cells; cells were unevenly distributed with reduced neuron numbers. Meanwhile, infiltration of lymphocytes and neutrophils occurred. In the FEO group after FEO intervention, necrotic cells were lesser, cell arrangement and nucleus morphology were obviously alleviated, and infiltration of inflammatory cells was reduced at corresponding time points. Compared with the sham-operation group, behavioral scores at 5 time points all decreased, the number of activated microglia was added, and expressions of TNF-α and IL-1 ß in hematoma tissue increased in the ICH group (P <0. 01). Compared with the ICH group, behavioral scores at 48 and 72 h, as well as day 7 all increased, the number of activated microglia was reduced, and expressions of TNF-α and IL-1ß in hematoma tissue decreased in the FEO group (P <0. 01). CONCLUSION: FEO using the ethanol reflux method could improve symptoms of ICH model rats possibly by inhibiting activation of microolia and the release of proinflammatory factors around the hematoma.

Decreased connexin 40 expression of the sinoatrial node mediates ischemic stroke-induced arrhythmia in mice.

BACKGROUND: Arrhythmia is the most common cardiac complication after ischemic stroke. Connexin 40 is the staple component of gap junctions, which influences the propagation of cardiac electrical signals in the sinoatrial node. However, the role of connexin 40 in post-stroke arrhythmia remains unclear. METHODS: In this study, a permanent middle cerebral artery occlusion model was used to simulate the occurrence of an ischemic stroke. Subsequently, an electrocardiogram was utilized to record and assess variations in electrocardiogram measures. In addition, optical tissue clearing and whole-mount immunofluorescence staining were used to confirm the anatomical localization of the sinoatrial node, and the sinoatrial node tissue was collected for RNA sequencing to screen for potential pathological mechanisms. Lastly, the rAAV9-Gja5 virus was injected with ultrasound guidance into the heart to increase Cx40 expression in the sinoatrial node. RESULTS: We demonstrated that the mice suffering from a permanent middle cerebral artery occlusion displayed significant arrhythmia, including atrial fibrillation, premature ventricular contractions, atrioventricular block, and abnormal electrocardiogram parameters. Of note, we observed a decrease in connexin 40 expression within the sinoatrial node after the ischemic stroke via RNA sequencing and western blot. Furthermore, rAAV9-Gja5 treatment ameliorated the occurrence of arrhythmia following stroke. CONCLUSIONS: In conclusion, decreased connexin 40 expression in the sinoatrial node contributed to the ischemic stroke-induced cardiac arrhythmia. Therefore, enhancing connexin 40 expression holds promise as a potential therapeutic approach for ischemic stroke-induced arrhythmia.

Inhibition of PARP1 improves cardiac function after myocardial infarction via up-regulated NLRC5.

The incidence and mortality rate of myocardial infarction are increasing per year in China. The polarization of macrophages towards the classically activated macrophages (M1) phenotype is of utmost importance in the progression of inflammatory stress subsequent to myocardial infarction. Poly (ADP-ribose) polymerase 1(PARP1) is the ubiquitous and best characterized member of the PARP family, which has been reported to support macrophage polarization towards the pro-inflammatory phenotype. Yet, the role of PARP1 in myocardial ischemic injury remains to be elucidated. Here, we demonstrated that a myocardial infarction mouse model induced cardiac damage characterized by cardiac dysfunction and increased PARP1 expression in cardiac macrophages. Inhibition of PARP1 by the PJ34 inhibitors could effectively alleviate M1 macrophage polarization, reduce infarction size, decrease inflammation and rescue the cardiac function post-MI in mice. Mechanistically, the suppression of PARP1 increase NLRC5 gene expression, and thus inhibits the NF-κB pathway, thereby decreasing the production of inflammatory cytokines such as IL-1ß and TNF-α. Inhibition of NLRC5 promote infection by effectively abolishing the influence of this mechanism discussed above. Interestingly, inhibition of NLRC5 promotes cardiac macrophage polarization toward an M1 phenotype but without having major effects on M2 macrophages. Our results demonstrate that inhibition of PARP1 increased NLRC5 gene expression, thereby suppressing M1 polarization, improving cardiac function, decreasing infarct area and attenuating inflammatory injury. The aforementioned findings provide new insights into the proinflammatory mechanisms that drive macrophage polarization following myocardial infarction, thereby introducing novel potential targets for future therapeutic interventions in individuals affected by myocardial infarction.

Monocyte-Derived Macrophages Aggravate Cardiac Dysfunction After Ischemic Stroke in Mice.

BACKGROUND: Cardiac damage induced by ischemic stroke, such as arrhythmia, cardiac dysfunction, and even cardiac arrest, is referred to as cerebral-cardiac syndrome (CCS). Cardiac macrophages are reported to be closely associated with stroke-induced cardiac damage. However, the role of macrophage subsets in CCS is still unclear due to their heterogeneity. Sympathetic nerves play a significant role in regulating macrophages in cardiovascular disease. However, the role of macrophage subsets and sympathetic nerves in CCS is still unclear. METHODS AND RESULTS: In this study, a middle cerebral artery occlusion mouse model was used to simulate ischemic stroke. ECG and echocardiography were used to assess cardiac function. We used Cx3cr1GFPCcr2RFP mice and NLRP3-deficient mice in combination with Smart-seq2 RNA sequencing to confirm the role of macrophage subsets in CCS. We demonstrated that ischemic stroke-induced cardiac damage is characterized by severe cardiac dysfunction and robust infiltration of monocyte-derived macrophages into the heart. Subsequently, we identified that cardiac monocyte-derived macrophages displayed a proinflammatory profile. We also observed that cardiac dysfunction was rescued in ischemic stroke mice by blocking macrophage infiltration using a CCR2 antagonist and NLRP3-deficient mice. In addition, a cardiac sympathetic nerve retrograde tracer and a sympathectomy method were used to explore the relationship between sympathetic nerves and cardiac macrophages. We found that cardiac sympathetic nerves are significantly activated after ischemic stroke, which contributes to the infiltration of monocyte-derived macrophages and subsequent cardiac dysfunction. CONCLUSIONS: Our findings suggest a potential pathogenesis of CCS involving the cardiac sympathetic nerve-monocyte-derived macrophage axis.

Role of galectin-3 in cardiac dysfunction induced by subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a severe acute cerebrovascular event that not only impairs the central nervous system but also negatively affects various other organs, including the heart. The underlying mechanisms, however, remain unclear. In this study, we discovered that mice with SAH exhibited significant cardiac injuries, such as extended QT and QTc intervals, cardiac fibrosis, and reduced cardiac ejection fractions. This phenomenon was accompanied by increased galectin-3 expression in the cardiac ventricle and can be reversed by galectin-3 inhibitor TD139. Interestingly, we also observed increased co-expression of galectin-3 in macrophage within the heart tissue of SAH mice. Additionally, when macrophage activation was suppressed using the beta-blocker propranolol, cardiac function improved, and galectin-3 expression in the cardiac tissue decreased. Collectively, our findings offer new insights into the role of galectin-3 in SAH-related cardiac dysfunction and suggest a macrophage-galectin-3 axis as a potential therapeutic strategy.

Guidewire-Assisted Reduction Technology Combined with Postural Reduction Improves the Success Rate of Internal Vein Catheterisation.

Objective: To investigate the value of guidewire-assisted reduction technology (which increases the stiffness of a catheter through the use of a guidewire, thereby protecting the puncture point and distal vein from breakage) combined with postural reduction for malpositioned catheters in the internal jugular vein during peripherally inserted central venous catheter catheterisation. Methods: From January 2015 to August 2020, we used ultrasound to perform guided puncture and monitoring. We identified the tip of the catheter as malpositioned in the internal jugular vein in 99 patients during the catheterisation process. These patients were divided randomly into a control group and an experimental group. In the control group, 43 cases received guidewire-assisted reduction technology, while in the experimental group, 56 patients received guidewire-assisted reduction technology combined with an upright posture. This study compared the efficacy of these two methods. Results: The results showed that 30 catheters were reduced successfully in the control group, with a success rate of 69.8%. In the experimental group, 53 cases were successfully reduced, with a success rate of 94.6%. The catheter reduction success rate in the experimental group was significantly higher than in the control group; this was a statistically significant difference (P=0.001). Conclusion: Guidewire-assisted reduction technology combined with postural reduction can improve the success rate of the reduction of malpositioned catheters in the internal jugular vein.

Definition of catheter jamming: A mechanical analysis of catheter fracture tension and fracture strain.

BACKGROUND: Catheter jamming is an emerging and possibly underrated complication. OBJECTIVE: To find the criteria for determining if the catheter cannot be removed through the mechanical analysis of fracture tension and fracture strain (εf) of Peripheral Inserted Central Catheters (PICC). METHOD: We removed 30 pieces of PICC catheters from patients and recorded the indwelling time. Those with an indwelling time shorter than 12 weeks belonged to the short-term group. Those with an indwelling time longer than 12 weeks belonged to the long-term group. The first half of the same catheter is section A, and the second half is section B. The fraction tension and fracture strain of the catheter were measured, and statistical analysis was conducted. RESULTS: The fracture tension of catheter in sections A and B were 5.8917 ± 1.0095 and 6.0670 ± 0.8066 Newtons respectively (p= 0.393) and the fracture strain of catheter in sections A and B were 6.0611 ± 1.0810 and 6.2543 ± 0.7187 Newtons respectively (p= 0.343). The fracture tension of catheter in short-term and long-term group were 6.0696 ± 0.9414 and 5.9192 ± 0.8972 Newtons respectively (p= 0.535) and the fracture strain of catheter in short-term and long-term group were 6.0067 ± 0.7227 and 6.2584 ± 1.0212 respectively (p= 0.301). CONCLUSION: It is objective and consistent to take the catheter fracture tension as the standard. This standard would be able to accurately define the concept of catheter failure and reduce the risk of catheter fracture and the misdiagnosis of catheter failure. The catheter fracture tension and fracture strain was not affected by the catheter indwelling time. It is recommended to set the tensile force as 5 Newtons and carry it out at a speed of 100 mm/min for the catheter drawing of the PICC single-lumen silicone catheter (4.0F) from Budd Company.

Isoflurane Attenuates Cerebral Ischaemia-Reperfusion Injury via the TLR4-NLRP3 Signalling Pathway in Diabetic Mice.

Ischaemic stroke is a severe disease worldwide. Restoration of blood flow after ischaemic stroke leads to cerebral ischaemia-reperfusion injury (CIRI). Various operations, such as cardiac surgery with deep hypothermic circulatory arrest, predictably cause cerebral ischaemia. Diabetes is related to the occurrence of perioperative stroke and exacerbates neurological impairment after stroke. Therefore, the choice of anaesthetic drugs has certain clinical significance for patients with diabetes. Isoflurane (ISO) exerts neuroprotective and anti-neuroinflammatory effects in patients without diabetes. However, the role of ISO in cerebral ischaemia in the context of diabetes is still unknown. Toll-like receptor 4 (TLR4) and NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome activation play important roles in microglia-mediated neuroinflammatory injury. In this study, we treated a diabetic middle cerebral artery occlusion mouse model with ISO. We found that diabetes exacerbated cerebral ischaemia damage and that ISO exerted neuroprotective effects in diabetic mice. Then, we found that ISO decreased TLR4-NLRP3 inflammasome activation in microglia and the excessive autophagy induced by CIRI in diabetic mice. The TLR4-specific agonist CRX-527 reversed the neuroprotective effects of ISO. In summary, our study indicated that ISO exerts neuroprotective effects against the neuroinflammation and autophagy observed during diabetic stroke via the TLR4-NLRP3 signalling pathway.

A Comparison of Lower Limb Peripherally Inserted Central Catheter and Deep Venous Catheterisation.

OBJECTIVE: To compare the clinical application effects of peripherally inserted central catheter (PICC) and deep venous catheters placed through the lower limbs in adults with malignancy obviating the use of upper limb PICC. STUDY DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Department of Oncology, Beijing Shijingshan Hospital, Capital Medical University, Beijing, China between February 2017 and February 2019. METHODOLOGY: The patients enrolled in this study were assigned to PICC under ultrasound guidance group and deep venous catheterisation group. The inclusion criteria were patients with advanced malignant tumor after bilateral breast cancer lymphadenectomy or superior vena cava obstruction syndrome; bedridden patients; and patients without mental disorders; who could understand the content of this study and agreed to participate in this study. Patients with high-risk thrombosis and venous thrombosis of lower limbs were excluded. The success rate of one-time catheterisation, the length of catheterisation puncture time, the number of catheterisations, and the occurrence of catheter-related complications of the two groups were compared. RESULTS: Ultrasound-guided PICC through the lower limbs had a higher success rate than deep venous catheterization (84.6% vs. 42.9%, p=0.046). The average length of puncture time in adults with PICC through the lower limbs under ultrasound guidance was shorter than that in the femoral vein group (24.69 ± 4.35 vs. 29.14 ± 6.02, p=0.038). No catheter-related infection was found in the two groups of patients. CONCLUSION: The indications for PICC through the lower limbs in adults include patients with advanced malignant tumor after bilateral breast cancer lymphadenectomy or superior vena cava obstruction syndrome, and mainly bedridden patients. This technique has certain advantages over deep venous catheterisation and is an effective choice for venous access. Key Words: Lower limb PICC, Deep venous catheterisation, Advanced malignant tumor, Bedridden.

Cerebral-Cardiac Syndrome and Diabetes: Cardiac Damage After Ischemic Stroke in Diabetic State.

Cerebral-cardiac syndrome (CCS) refers to cardiac dysfunction following varying brain injuries. Ischemic stroke is strongly evidenced to induce CCS characterizing as arrhythmia, myocardial damage, and heart failure. CCS is attributed to be the second leading cause of death in the post-stroke stage; however, the responsible mechanisms are obscure. Studies indicated the possible mechanisms including insular cortex injury, autonomic imbalance, catecholamine surge, immune response, and systemic inflammation. Of note, the characteristics of the stroke population reveal a common comorbidity with diabetes. The close and causative correlation of diabetes and stroke directs the involvement of diabetes in CCS. Nevertheless, the role of diabetes and its corresponding molecular mechanisms in CCS have not been clarified. Here we conclude the features of CCS and the potential role of diabetes in CCS. Diabetes drives establish a "primed" inflammatory microenvironment and further induces severe systemic inflammation after stroke. The boosted inflammation is suspected to provoke cardiac pathological changes and hence exacerbate CCS. Importantly, as the key element of inflammation, NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome is indicated to play an important role in diabetes, stroke, and the sequential CCS. Overall, we characterize the corresponding role of diabetes in CCS and speculate a link of NLRP3 inflammasome between them.

NLRP3 Inflammasome: A Potential Target in Isoflurane Pretreatment Alleviates Stroke-Induced Retinal Injury in Diabetes.

Ischemic stroke remains a devastating disease which is the leading cause of death worldwide. Visual impairment after stroke is a common complication which may lead to vision loss, greatly impacting life quality of patients. While ischemic stroke is traditionally characterized by a blockage of blood flow to the brain, this may coincide with reduced blood flow to the eye, resulting in retinal ischemia and leading to visual impairment. Diabetes increases the risk of ischemic stroke and induces diabetic retinopathy; the latter may be more sensitive to the ischemic retinal injury. In diabetic status, the underlying mechanism in stroke-induced retinal injury has not been fully clarified. The NLR pyrin domain containing 3 (NLRP3) inflammasome is an important activator of inflammation, which may play a critical role in catalyzing and forming certain pro-inflammatory cytokines in both cerebral and retinal ischemia. Isoflurane has been demonstrated to inhibit the activation of the NLRP3 inflammasome and show neuroprotective effects. In this study, we established a diabetic mouse model and performed the middle cerebral artery occlusion procedure to induce ischemic stroke. Our results revealed that cerebral ischemia-induced retinal injury in the diabetic model. Isoflurane pretreatment alleviated the cerebral and retinal injury after ischemic stroke. Of note, isoflurane pretreatment inhibited the NLRP3 inflammasome activation in the retina, indicating that isoflurane pretreatment may provide substantial retinal protection in stroke-induced retinal injury in diabetes.

Macrophage-NLRP3 Inflammasome Activation Exacerbates Cardiac Dysfunction after Ischemic Stroke in a Mouse Model of Diabetes.

Ischemic stroke is one of the leading causes of death worldwide. In the post-stroke stage, cardiac dysfunction is common and is known as the brain-heart interaction. Diabetes mellitus worsens the post-stroke outcome. Stroke-induced systemic inflammation is the major causative factor for the sequential complications, but the mechanism underlying the brain-heart interaction in diabetes has not been clarified. The NLRP3 (NLR pyrin domain-containing 3) inflammasome, an important component of the inflammation after stroke, is mainly activated in M1-polarized macrophages. In this study, we found that the cardiac dysfunction induced by ischemic stroke is more severe in a mouse model of type 2 diabetes. Meanwhile, M1-polarized macrophage infiltration and NLRP3 inflammasome activation increased in the cardiac ventricle after diabetic stroke. Importantly, the NLRP3 inflammasome inhibitor CY-09 restored cardiac function, indicating that the M1-polarized macrophage-NLRP3 inflammasome activation is a pathway underlying the brain-heart interaction after diabetic stroke.

[Questionnaire survey of guideline implementation for community acquired pneumonia with retrospective analysis of the empiric treatment in 490 patients].

OBJECTIVE: To assess physicians' awareness and use of guidelines for community-acquired pneumonia (CAP) published by Chinese Society of Respiratory Diseases (CSRD) and American Thoracic Society (ATS), and to investigate influences of the guidelines on the prognosis of patients with CAP. METHOD: A total of 210 self-completion questionnaires about CAP guidelines were received from doctors of six hospitals in Beijing. In addition, 490 serial cases of CAP collected from these hospitals admitted from January 2002 to December 2003 were retrospectively analyzed. RESULTS: Most doctors had limited knowledge about atypical pathogens. For pulmonary physicians, only 46% (97/210) reported using the CSRD guideline. 82.4% of the doctors preferred to give initial empiric antibiotic therapy according to the patients' conditions. 79.5% (167/210) of the doctors ordered examination of the pathogens routinely and 84.3% (177/210) of them admitted its usefulness for choosing antibiotics. 84.5% (414/490) of the patients responded well to the initial empiric treatment. Patients who were treated according to the guidelines of CSRD and ATS were 229 cases and 131 cases respectively. There was no significant difference in the prognosis between patients who were treated according to the guideline and those who were not. There was no significant difference in the prognosis between cases with definite pathogens and cases without. CONCLUSIONS: The results indicate low levels of awareness and use of guidelines for the management of CAP. Fewer than half of the patients were treated according to the guidelines. However, the treatments were effective in most of the patients, and there was no significant difference in the prognosis between patients who were treated according to the guideline and those who were not, because broad-spectrum antibiotics were overused. More effective guideline implementation strategies are needed to encourage compliance with practice guidelines for the management of CAP.

Activation of p47phox as a Mechanism of Bupivacaine-Induced Burst Production of Reactive Oxygen Species and Neural Toxicity.

Bupivacaine has been shown to induce neurotoxicity through inducing excessive reactive oxygen species (ROS), but the underlying mechanism remains unclear. NOX2 is one of the most important sources of ROS in the nervous system, and its activation requires the membrane translocation of subunit p47phox. However, the role of p47phox in bupivacaine-induced neurotoxicity has not been explored. In our in vitro study, cultured human SH-SY5Y neuroblastoma cells were treated with 1.5 mM bupivacaine to induce neurotoxicity. Membrane translocation of p47phox was assessed by measuring the cytosol/membrane ratio of p47phox. The effects of the NOX inhibitor VAS2870 and p47phox-siRNA on bupivacaine-induced neurotoxicity were investigated. Furthermore, the effect of VAS2870 on bupivacaine-induced neurotoxicity was assessed in vivo in rats. All these changes were reversed by pretreatment with VAS2870 or transfection with p47phox-siRNA in SH-SY5Y cells. Similarly, pretreatment with VAS2870 attenuated bupivacaine-induced neuronal toxicity in rats. It is concluded that enhancing p47phox membrane translocation is a major mechanism whereby bupivacaine induced neurotoxicity and that pretreatment with VAS2870 or local p47phox gene knockdown attenuated bupivacaine-induced neuronal cell injury.

Administration of fentanyl via a slow intravenous fluid line compared with rapid bolus alleviates fentanyl-induced cough during general anesthesia induction.

OBJECTIVE: Fentanyl-induced cough (FIC) is a common complication with a reported incidence from 18.0% to 74.4% during general anesthesia induction. FIC increases the intrathoracic pressure and risks of postoperative nausea and vomiting, yet available treatments are limited. This study was designed to investigate whether administering fentanyl via a slow intravenous fluid line can effectively alleviate FIC during induction of total intravenous general anesthesia. METHODS: A total number of 1200 patients, aged 18-64 years, were enrolled, all of whom were American Society of Anesthesiologists (ASA) grade I or II undergoing scheduled surgeries. All patients received total intravenous general anesthesia, which was induced sequentially by midazolam, fentanyl, propofol, and cisatracurium injection. Patients were randomly assigned to receive fentanyl 3.5 µg/kg via direct injection (control group) or via a slow intravenous fluid line. FIC incidence and the severity grades were analyzed with the Mann-Whitney test. Other adverse reactions, such as hypotension, hypertension, bradycardia, tachycardia, hypoxemia, vomiting, and aspiration, during induction were also observed. The online clinical registration number of this study was ChiCTR-IOR-16009025. RESULTS: Compared with the control group, the incidence of FIC was significantly lower in the slow intravenous fluid line group during induction (9.1%, 95% confidence interval (CI): 6.7%-11.4% vs. 55.9%, 95% CI: 51.8%-60.0%, P=0.000), as were the severity grades (P=0.000). There were no statistical differences between the two groups with regard to other adverse reactions (P>0.05). CONCLUSIONS: The administration of fentanyl via a slow intravenous fluid line can alleviate FIC and its severity during induction for total intravenous general anesthesia. This method is simple, safe, and reliable, and deserves clinical expansion.

Neurotoxicity Comparison of Two Types of Local Anaesthetics: Amide-Bupivacaine versus Ester-Procaine.

Local anaesthetics (LAs) may lead to neurological complications, but the underlying mechanism is still unclear. Many neurotoxicity research studies have examined different LAs, but none have comprehensively explored the distinct mechanisms of neurotoxicity caused by amide- (bupivacaine) and ester- (procaine) type LAs. Here, based on a CCK8 assay, LDH assay, Rhod-2-AM and JC-1 staining, 2',7'-dichlorohy-drofluorescein diacetate and dihydroethidium probes, an alkaline comet assay, and apoptosis assay, we show that both bupivacaine and procaine significantly induce mitochondrial calcium overload and a decline in the mitochondrial membrane potential as well as overproduction of ROS, DNA damage and apoptosis (P < 0.05). There were no significant differences in mitochondrial injury and apoptosis between the bupivacaine and procaine subgroups (P > 0.05). However, to our surprise, the superoxide anionic level after treatment with bupivacaine, which leads to more severe DNA damage, was higher than the level after treatment with procaine, while procaine produced more peroxidation than bupivacaine. Some of these results were also affirmed in dorsal root ganglia neurons of C57 mice. The differences in the superoxidation and peroxidation induced by these agents suggest that different types of LAs may cause neurotoxicity via different pathways. We can target more accurate treatment based on their different mechanisms of neurotoxicity.