The neurovascular unit (NVU) consists of neurons,gllal cells and microvessels,etc.There were complex interactions among the various cellular components,which form as a uniform entirety preferably.Anong the various cellular components of NVU,the signal transduction occurred disorders during cerebral ischemia,resulting in neuronal and extracellular ratrix destruction,and thus occurring cerebral infarction and hemorrhagic transformation.Therefore,the treatment of ischemic sttroke should be based on the protection of the overall function of NVU.This article describes the changes and protection of NVU after cerebral ischemia.

Objective:To investigate the status of regional citrate anticoagulation (RCA) in continuous renal replacement therapy (CRRT) in emergency department.Methods:Participants of a national emergency conference from August 1st to August 4th in 2019 from hospitals of different levels in different regions were interviewed by online questionnaire to collect data about the current status and limitations of the application of RCA in emergency CRRT by convenient sampling.Results:Totally 407 questionnaires were collected through internet, and the completeness of the answers was as high as 100%. Twenty-three responses with logic errors were excluded, and 384 questionnaires were finally retrieved, with an effective rate of 94.35%. Representatives from 29 provinces, autonomous regions and municipalities directly under the Central Government participated in the questionnaire survey, and the hospitals in which they worked were mainly class Ⅲ grade A [70.31% (270/384)]. The survey showed that 61.46% (236/384) of the emergency departments could carry out CRRT independently. There were less than 10 CRRT cases per month in most emergency departments [52.87% (166/314)]. In the emergency departments where CRRT were carried out, heparin was a widely used and well-applied anticoagulant [82.17% (258/314)], and 199 emergency departments (63.38%) were proficient in RCA. In clinical practice, heparin [49.68% (156/314)] was preferred to RCA [25.80% (81/314)] and low molecular weight heparin [23.56% (74/384)]. In the emergency departments where RCA could be used skillfully, 4% sodium citrate was the main regional anticoagulant [68.34% (136/199)]. Anticoagulation protocol came from different sources, most of which were from nephrology or dialysis center (29.65%). Most departments could adjust the ionized calcium before the filter to the target safety level [0.9-1.2 mmol/L, 88.94% (177/199)], and adjust the ionized calcium after the filter to the target ideal anticoagulation level [0.2-0.4 mmol/L, 93.47% (186/199)] within 4 hours. The common complications that emergency physicians concerned were accumulation of citrate [58.29% (116/199)], metabolic alkalosis [54.77% (109/199)] and metabolic acidosis [37.19% (74/199)]. In 281 emergency departments that could not use RCA, there were kinds of factors that limited the use of citrate, such as higher cost than heparin (31.67%), unskilled personnel (21.00%), limited source of citrate (17.08%), concerns of complications (11.74%). At present, the substitution fluids used in clinical practice were mainly the commercial products (45.54%). In most cases, emergency CRRT filters had a life span of 12-23 hours (39.49%).Conclusions:The use of RCA in domestic emergency CRRT is low. Compared with the international peers, we are still lacking of adequate understanding of RCA. Therefore, it is necessary to develop an anticoagulation protocol of RCA for emergency departments in China, and promote training of CRRT.