Respiratory complications of propofol,sevoflurane,and dexmedetomidine anesthesia for fiberoptic bronchoscopy in children aged 1 month to 3 years:a randomized trial

Objective To evaluate the effect of propofol,sevoflurane,and dexmedetomidine on respiratory complications inchildren undergoing fiberoptic bronchoscopy(FOB).Methods This double-blind randomized clinical trial was conductedamong 120 children aged 1 month to 3 years undergoing FOB.The patients were randomized into 3 groups(n=40)foranesthesia induction with sevoflurane inhalation,1 mg/kg propofol,or 1μg/kg dexmedetomidine before bronchoscopy,andthe changes in hemodynamic parameters,sedation level,and respiratory complications during and after the procedure wereassessed.Results The patients'heart rate during bronchoscopy was significantly lower and the mean arterial blood pressuresignificantly higher in dexmedetomidine group than in sevoflurane and propofol groups(P<0.05).Cough duringbronchoscopy did not occur in any of the cases in propofol group,while the highest frequency of cough was recorded indexmedetomidine group.The incidence of laryngospasm in the propofol group(12.5%)was significantly lower than those insevoflurane and dexmedetomidine groups(30%and 32.5%,respectively)(P<0.05).Conclusion Sevoflurane and propofol aresafe and suitable for anesthesia induction in children below 3 years of age undergoing diagnostic FOB and can achieve bettersedative effect and lower the incidences of cough and respiratory complications as compared with dexmedetomidine.

Comparative observation of the effectiveness and safety of remimazolam besylate versus dexmedetomidine in gastrointestinal surgery in obese patients

BACKGROUND Surgery for obese patients carries a higher risk of anesthesia complications compared with surgery for nonobese patients.Thus,a safe and effective anesthesia strategy is necessary to improve the medical experience of such patients and ensure their safety.AIM To compared the effectiveness and safety of remimazolam besylate versus dexmedetomidine(DEX)in gastrointestinal surgery in obese patients.METHODS The study cohort included 60 obese patients undergoing gastrointestinal surgery between July 2021 and April 2023,comprising 30 patients who received DEX intervention(control group)and 30 patients who received remimazolam besylate intervention(research group).Heart rate(HR),respiratory rate(RR),mean arterial pressure(MAP),blood oxygen saturation(SpO_(2)),safety(nausea and vomiting,bradycardia,hypotension,and apnea),anesthesia and examination indices[induction time,anesthesia recovery time,and postanesthesia care unit(PACU)discharge time],sedation effect(Ramsay Sedation Scale),and postoperative pain visual analog scale were comparatively analyzed before anesthesia(T0),during anesthesia(T1),and after anesthesia(T2).RESULTS At T1,the research group showed significantly smaller changes in HR,RR,MAP,and SpO_(2) than the control group,with a significantly lower adverse reaction rate and shorter induction,anesthesia recovery,and PACU discharge times.Additionally,the intra-and postoperative Ramsay Sedation Scale scores were statistically higher in the research group than in the control group.CONCLUSION Remimazolam besylate was significantly more effective than DEX in gastrointestinal surgery in obese patients and had a higher safety profile and value in clinical promotion.

Dexmedetomidine ameliorates diabetic intestinal injury by promoting the polarization of M2 macrophages through the MMP23B pathway

BACKGROUND Diabetes is often associated with gastrointestinal dysfunctions,which can lead to hypoglycemia.Dexmedetomidine(DEX)is a commonly used sedative in perioperative diabetic patients and may affect gastrointestinal function.AIM To investigate whether sedative doses of DEX alleviate diabetes-caused intestinal dysfunction.METHODS Sedation/anesthesia scores and vital signs of streptozotocin(STZ)-induced diabetic mice under DEX sedation were observed.Diabetic mice were divided into saline and DEX groups.After injecting sedatives intraperitoneally,tight junctions(TJs)and apoptotic levels were evaluated 24 hours later to assess the intestinal barrier function.The role of DEX was validated using Villin-MMP23B flox/flox mice with intestinal epithelial deletion.In vitro,high glucose and hyperosmolarity were used to culture Caco-2 monolayer cells with STZ intervention.Immunofluorescence techniques were used to monitor the barrier and mitochondrial functions.RESULTS MMP23B protein levels in the intestinal tissue of STZ-induced diabetic mice were significantly higher than those in the intestinal tissue of control mice,with the DEX group displaying decreased MMP23B levels.Diabetes-mediated TJ disruption,increased intestinal mucosal permeability,and systemic inflammation in wild-type mice might be reversed by DEX.In Caco-2 cells,MMP23B was associated with increased reactive oxygen species accumulation,mitochondrial membrane potential depolarization,and TJ disruption.CONCLUSION DEX reduces MMP23B,which may potentially contribute to STZ-induced intestinal barrier dysfunction,affecting TJ modification through mitochondrial dysfunction.

Effects of ulinastatin combined with dexmedetomidine on cognitive dysfunction and emergence agitation in elderly patients who underwent total hip arthroplasty

BACKGROUND With the continuous growth of the modern elderly population,the risk of fracture increases.Hip fracture is a common type of fracture in older people.Total hip arthroplasty(THA)has significant advantages in relieving chronic pain and promoting the recovery of hip joint function.AIM To investigate the effect of ulinastatin combined with dexmedetomidine(Dex)on the incidences of postoperative cognitive dysfunction(POCD)and emergence agitation in elderly patients who underwent THA.METHODS A total of 397 patients who underwent THA from February 2019 to August 2022.We conducted a three-year retrospective cohort study in Shaanxi Provincial People’s Hospital.Comprehensive demographic data were obtained from the electronic medical record system.We collected preoperative,intraoperative,and postoperative data.One hundred twenty-nine patients who were administered Dex during the operation were included in the Dex group.One hundred fifty patients who were intravenously injected with ulinastatin 15 min before anesthesia induction were included in the ulinastatin group.One hundred eighteen patients who were administered ulinastatin combined with Dex during the operation were included in the Dex+ulinastatin group.The patients’perioperative conditions,hemodynamic indexes,postoperative Mini-Mental State Examination(MMSE)scores,Ramsay score,incidence of POCD,and serum inflammatory cytokines were evaluated.RESULTS There was a significant difference in the 24 h visual analogue scale score among the three groups,and the score in the Dex+ulinastatin group was the lowest(P<0.05).Compared with the Dex and ulinastatin group,the MMSE scores of the Dex+ulinastatin group were significantly increased at 1 and 7 d after the operation(all P<0.05).Compared with those in the Dex and ulinastatin groups,incidence of POCD,levels of serum inflammatory cytokines in the Dex+ulinastatin group were significantly decreased at 1 and 7 d after the operation(all P<0.05).The observer’s assessment of the alertness/sedation score and Ramsay score of the Dex+ulinastatin group were significantly different from those of the Dex and ulinastatin groups on the first day after the operation(all P<0.05).CONCLUSION Ulinastatin combined with Dex can prevent the occurrence of POCD and emergence agitation in elderly patients undergoing THA.

Brain protective effect of dexmedetomidine vs propofol for sedation during prolonged mechanical ventilation in non-brain injured patients

BACKGROUND Dexmedetomidine and propofol are two sedatives used for long-term sedation.It remains unclear whether dexmedetomidine provides superior cerebral protection for patients undergoing long-term mechanical ventilation.AIM To compare the neuroprotective effects of dexmedetomidine and propofol for sedation during prolonged mechanical ventilation in patients without brain injury.METHODS Patients who underwent mechanical ventilation for>72 h were randomly assigned to receive sedation with dexmedetomidine or propofol.The Richmond Agitation and Sedation Scale(RASS)was used to evaluate sedation effects,with a target range of-3 to 0.The primary outcomes were serum levels of S100-βand neuron-specific enolase(NSE)every 24 h.The secondary outcomes were remifentanil dosage,the proportion of patients requiring rescue sedation,and the time and frequency of RASS scores within the target range.RESULTS A total of 52 and 63 patients were allocated to the dexmedetomidine group and propofol group,respectively.Baseline data were comparable between groups.No significant differences were identified between groups within the median duration of study drug infusion[52.0(IQR:36.0-73.5)h vs 53.0(IQR:37.0-72.0)h,P=0.958],the median dose of remifentanil[4.5(IQR:4.0-5.0)μg/kg/h vs 4.6(IQR:4.0-5.0)μg/kg/h,P=0.395],the median percentage of time in the target RASS range without rescue sedation[85.6%(IQR:65.8%-96.6%)vs 86.7%(IQR:72.3%-95.3),P=0.592],and the median frequency within the target RASS range without rescue sedation[72.2%(60.8%-91.7%)vs 73.3%(60.0%-100.0%),P=0.880].The proportion of patients in the dexmedetomidine group who required rescue sedation was higher than in the propofol group with statistical significance(69.2%vs 50.8%,P=0.045).Serum S100-βand NSE levels in the propofol group were higher than in the dexmedetomidine group with statistical significance during the first six and five days of mechanical ventilation,respectively(all P<0.05).CONCLUSION Dexmedetomidine demonstrated stronger protective effects on the brain compared to propofol for long-term mechanical ventilation in patients without brain injury.

Impact of dexmedetomidine-assisted anesthesia in elderly patients undergoing radical resection of colon cancer

BACKGROUND Radical resection of colon cancer under general anesthesia is one of the main treatment methods for this malignancy.However,due to the physiological charac-teristics of elderly patients,the safety of perioperative anesthesia needs special attention.As anα2-adrenergic receptor agonist,dexmedetomidine(Dex)has attracted much attention from anesthesiologists due to its stabilizing effect on heart rate and blood pressure,inhibitory effect on inflammation,and sedative and analgesic effects.Its application in general anesthesia may have a positive impact on the quality of anesthesia and postoperative recovery in elderly patients undergoing radical resection of colon cancer.METHODS A total of 165 colon cancer patients who underwent radical surgery for colon cancer under general anesthesia at Qingdao University Affiliated Haici Hospital,Qingdao,China were recruited and divided into two groups:A and B.In group A,Dex was administered 30 min before surgery,while group B received an equivalent amount of normal saline.The hemodynamic changes,pulmonary compliance,airway pressure,inflammatory factors,confusion assessment method scores,Ramsay Sedation-Agitation Scale scores,and cellular immune function indicators were compared between the two groups.RESULTS Group A showed less intraoperative hemodynamic fluctuations,better pulmonary compliance,and lower airway resistance compared with group B.Twelve hours after the surgery,the serum levels of TLR-2,TLR-4,IL-6,and TNF-αin group A were significantly lower than those of group B(P<0.05).After extubation,the Ramsay Sedation-Agitation Scale score of group A patients was significantly higher than that of group B patients,indicating a higher level of sedation.The incidence of delirium was significantly lower in group A than in group B(P<0.05).CONCLUSION The use of Dex as an adjunct to general anesthesia for radical surgery in elderly patients with colon cancer results in better effectiveness of anesthesia.

Application value of dexmedetomidine in anesthesia for elderly patients undergoing radical colon cancer surgery

BACKGROUND Colon cancer presents a substantial risk to the well-being of elderly people worldwide.With advancements in medical technology,surgical treatment has become the primary approach for managing colon cancer patients.However,due to age-related physiological changes,especially a decline in cognitive function,older patients are more susceptible to the effects of surgery and anesthesia,increasing the relative risk of postoperative cognitive dysfunction(POCD).There-fore,in the surgical treatment of elderly patients with colon cancer,it is of pa-ramount importance to select an appropriate anesthetic approach to reduce the occurrence of POCD,protect brain function,and improve surgical success rates.METHODS One hundred and seventeen patients with colon cancer who underwent elective surgery under general anesthesia were selected and divided into two groups:A and B.Group A received Dex before anesthesia induction,and B group received an equivalent amount of normal saline.Changes in the mini-mental state exami-nation,regional cerebral oxygen saturation(rSO2),bispectral index,glucose uptake rate(GluER),lactate production rate(LacPR),serum S100βand neuron-specific enolase(NSE),POCD,and adverse anesthesia reactions were compared between the two groups.RESULTS Surgical duration,duration of anesthesia,and intraoperative blood loss were comparable between the two groups(P>0.05).The overall dosage of anesthetic drugs used in group A,including propofol and remifentanil,was significantly lower than that used in group B(P<0.05).Group A exhibited higher rSO2 values at the time of endotracheal intubation,30 min after the start of surgery,and immediately after extubation,higher GluER values and lower LacPR values at the time of endotra-cheal intubation,30 min after the start of surgery,immediately after extubation,and 5 min after extubation(P<0.05).Group A exhibited lower levels of serum S100βand NSE 24 h postoperatively and a lower incidence of cognitive dysfunction on the 1st and 5th postoperative days(P<0.05).CONCLUSION The use of Dex in elderly patients undergoing radical colon cancer surgery helps maintain rSO2 Levels and reduce cerebral metabolic levels and the incidence of anesthesia-and surgery-induced cognitive dysfunction.

Effect of Dexmedetomidine on Maintaining Perioperative Hemodynamic Stability in Elderly Patients:A Systematic Review and Meta-analysis

Objective Dexmedetomidine is a highly selective alpha-2 adrenergic receptor agonist with sedative and analgesic properties but without respiratory depression effect and has been widely used in perioperative anesthesia.Here we performed a systematic review and meta-analysis to evaluate the effect of dexmedetomidine on maintaining perioperative hemodynamic stability in elderly patients.Methods PubMed,Web of Science,the Cochrane Library,China National Knowledge Infrastructure(CNKI),and Wanfang Data were searched for randomized-controlled trials(RCTs)on the application of dexmedetomidine in maintaining perioperative hemodynamic stability in elderly patients from their inception to September,2021.The standardized mean differences(SMD)with 95%confidence interval(CI)were employed to analyze the data.The random-effect model was used for the potential clinical inconsistency.Results A total of 12 RCTs with 833 elderly patients(dexmedetomidine group,546 patients;control group,287 patients)were included.There was no significant increase in perioperative heart rate(HR),mean arterial pressure(MAP),and diastolic blood pressure(DBP)in the dexmedetomidine group before and during the operation.In addition,the variations of hemodynamic indexes including HR,MAP,SBP(systolic blood pressure),and DBP were significantly lower in the dexmedetomidine group compared with the control group(HR:SMD=-0.87,95%CI:-1.13 to-0.62;MAP:SMD=-1.12,95%CI:-1.60 to-0.63;SBP:SMD=-1.27,95%CI:-2.26 to-0.27;DBP:SMD=-0.96,95%CI:-1.33 to-0.59).Subgroup analysis found that with the prolongation of 1.0μg/kg dexmedetomidine infusion,the patient’s heart rate declined in a time-dependent way.Conclusion Dexmedetomidine provides more stable hemodynamics during perioperative period in elderly patients.However,further well-conducted trials are required to assess the effective and safer doses of dexmedetomidine in elderly patients.

Influences of dexmedetomidine on stress responses and postoperative cognitive and coagulation functions in patients undergoing radical gastrectomy under general anesthesia

BACKGROUND Radical gastrectomy(RG)is commonly used in the treatment of patients with gastric cancer(GC),but this procedure may lead to stress responses,postoperative cognitive dysfunction,and blood coagulation abnormalities in patients.AIM To investigate the influences of dexmedetomidine(DEX)on stress responses and postoperative cognitive and coagulation functions in patients undergoing RG under general anesthesia(GA).METHODS One hundred and two patients undergoing RG for GC under GA from February 2020 to February 2022 were retrospectively reviewed.Of these,50 patients had received conventional anesthesia intervention[control group(CG)]and 52 patients had received DEX in addition to routine anesthesia intervention[observation group(OG)].Inflammatory factor(IFs;tumor necrosis factor-α,TNF-α;interleukin-6,IL-6),stress responses(cortisol,Cor;adrenocorticotropic hormone,ACTH),cognitive function(CF;Mini-Mental State Examination,MMSE),neurological function(neuron-specific enolase,NSE;S100 calciumbinding protein B,S100B),and coagulation function(prothrombin time,PT;thromboxane B2,TXB2;fibrinogen,FIB)were compared between the two groups before surgery(T0),as well as at 6 h(T1)and 24 h(T2)after surgery.RESULTS Compared with T0,TNF-α,IL-6,Cor,ACTH,NSE,S100B,PT,TXB2,and FIB showed a significant increase in both groups at T1 and T2,but with even lower levels in OG vs CG.Both groups showed a significant reduction in the MMSE score at T1 and T2 compared with T0,but the MMSE score was notably higher in OG compared with CG.CONCLUSION In addition to a potent inhibitory effect on postoperative IFs and stress responses in GC patients undergoing RG under GA,DEX may also alleviate the coagulation dysfunction and improve the postoperative CF of these patients.

Clinical Observation of Hemodynamic and Cerebral Protective Effects of Different Doses of Dexmedetomidine in Patients with Traumatic Brain Injury

Background: Patients with craniocerebral trauma may suffer ischemic brain injury and neurological dysfunction due to immune inflammation and neuroendocrine reactions. Dexmedetomidine (Dex) is one of the commonly used anesthetic drugs in clinic. Studies have shown Dex has the function of protecting brain nerves and inhibiting inflammation. However, there are few studies on the effects of different doses of dexmedetomidine on patients undergoing surgery. The purpose of this study is to observe the effects of different doses of Dex on hemodynamics and brain protection in patients undergoing brain trauma surgery. Materials and Methods: Eighty patients with craniocerebral trauma surgery were randomly divided into study group (group A, n = 40) and control group (group B, n = 40) by random number table method. Dex pump volume was 0.5 μg/kg/h in group A and 1.0 μg/kg/h in group B. Heart rate (HR) and mean arterial pressure (MAP) were recorded before anesthesia induction (T0), immediately after endotracheal intubation (T1) and at the end of operation (T2). The serum levels of central nervous system specific protein (S-100β) and neuron specific enolase (NSE) were measured and compared between the two groups at T0 and T2. Results: HR and MAP in group A were significantly higher than those in group B at T2, and the difference was statistically significant (P P β and NSE in both groups at T2 were lower than those at T0, and the concentrations of S-100β and NSE in group A were significantly lower than those in group B at T2 (P Conclusions: 0.5 μg/kg dose of Dex is stable in hemodynamics and has a better protective effect on brain function in patients with traumatic brain injury.

Dexmedetomidine-induced anesthesia in elderly patients undergoing hip replacement surgery

BACKGROUND A femoral neck fracture is a common and frequently reported issue in orthopedics, with a greater rate of incidence among the elderly. Due to their advanced age and the presence of some primary diseases, both anesthesia and surgery are increasingly difficult in elderly patients with a femoral neck fractures. In fact,general anesthesia can easily induce complications such as cognitive dysfunction,which is not conducive to postoperative recovery.AIM To analyze the efficacy of dexmedetomidine in inducing anesthesia for elderly patients undergoing hip replacement surgery.METHODS A total of 98 elderly patients undergoing hip replacement in our hospital from June 2020 to June 2021 were randomly divided into control group(49 cases) and observation group(49 cases). The control group was given general anesthesia, and the observation group was combined with dexmedetomidine for anesthesia on the basis of the control group. Both groups were observed until the patients were discharged. The vital signs, serum inflammatory factors and renal function indexes of the two groups were compared before, during and 6 h after operation.The postoperative recovery and adverse events of the two groups were statistically analyzed.RESULTS Compared with the mean arterial pressure of the two groups, the intraoperative and postoperative 6 h was higher than that before the operation, the intraoperative was lower than the postoperative 6 h(P < 0.05);the blood oxygen saturation of the two groups was higher than that before operation and 6 h after operation, and the observation group was higher than the control group 6 h after operation(P < 0.05). The heart rate of the two groups was lower during and 6 h after operation than that before operation, and higher at 6 h after operation than that during operation(P < 0.05).The levels of serum C-reactive protein, tumor necrosis factor-α, interleukin-1β and kidney injury molecule-1 in the two groups were higher during operation and 6 h after operation than those before operation(P < 0.05). The level of serum urea nitrogen in the two groups was higher than that before operation, and that in the observation group was lower than that in the control group(P < 0.05). During hospitalization, the first time of getting out of bed, recovery time of grade Ⅱ muscle strength, recovery time of grade Ⅲ muscle strength and hospitalization time in the observation group were shorter than those in the control group(P < 0.05).CONCLUSION Dexmedetomidine can effectively improve the vital signs of elderly patients undergoing hip replacement surgery, reduce the body’s inflammatory response and renal function damage, and promote postoperative recovery. Meanwhile, dexmedetomidine showcased a good safety profile and a good anesthetic outcome.

Hemodynamic instability following intravenous dexmedetomidine infusion for sedation under brachial plexus block: Two case reports

BACKGROUND Dexmedetomidine(DMED)is frequently used as a sedative in several medical fields.The benefits of DMED include enhanced quality of regional anesthesia,prolonged analgesia,and postoperative opioid-sparing when administered intravenously or perineurally in combination with regional anesthesia.Severe hemodynamic complications,such as profound bradycardia and hypotension,can occur after DMED administration in critically ill patients or overdosage;however,there are few reports of complications with DMED administration following brachial plexus block(BPB).CASE SUMMARY We present two cases of hemodynamic instability that occurred following the initial loading of DMED under supraclavicular BPB.A healthy 29-year-old man without any medical history showed profound bradycardia after receiving a loading dose of DMED 0.9μg/kg for 9 min.DMED administration was promptly stopped,and after receiving a second dose of atropine,the heart rate recovered.A 62-year-old woman with a history of cardiomyopathy became hypotensive abruptly,requiring the administration of inotrope and vasopressors after receiving a reduced loading dose of 0.5μg/kg for 10 min.Half of the recommended loading dose of DMED was administered due to the underlying heart dysfunction.Decrea-sed blood pressure was maintained despite the intravenous administration of ephedrine.With continuous infusion of dopamine and norepinephrine,the vital signs were maintained within normal ranges.Inotropic and vasopressor support was required for over 6 h after the initial loading dose of DMED.CONCLUSION DMED administration following BPB could trigger hemodynamic instability in patients with decreased cardiac function as well as in healthy individuals.

Clonidine use during dexmedetomidine weaning:A systematic review

BACKGROUND Dexmedetomidine is a centrally acting alpha-2A adrenergic agonist that is commonly used as a sedative and anxiolytic in the intensive care unit(ICU),with prolonged use increasing risk of withdrawal symptoms upon sudden discontinuation.As clonidine is an enterally available alpha-2A adrenergic agonist,it may be a suitable agent to taper off dexmedetomidine and reduce withdrawal syndromes.The appropriate dosing and conversion strategies for using enteral clonidine in this context are not known.The objective of this systematic review is to summarize the evidence of enteral clonidine application during dexmedetomidine weaning for prevention of withdrawal symptoms.AIM To systematically review the practice,dosing schema,and outcomes of enteral clonidine use during dexmedetomidine weaning in critically ill adults.METHODS This was a systematic review of enteral clonidine used during dexmedetomidine weaning in critically ill adults(≥18 years).Randomized controlled trials,prospective cohorts,and retrospective cohorts evaluating the use of clonidine to wean patients from dexmedetomidine in the critically ill were included.The primary outcomes of interest were dosing and titration schema of enteral clonidine and dexmedetomidine and risk factors for dexmedetomidine withdrawal.Other secondary outcomes included prevalence of adverse events associated with enteral clonidine use,re-initiation of dexmedetomidine,duration of mechanical ventilation,and ICU length of stay.RESULTS A total of 3427 studies were screened for inclusion with three meeting inclusion criteria with a total of 88 patients.All three studies were observational,two being prospective and one retrospective.In all included studies,the choice to start enteral clonidine to wean off dexmedetomidine was made at the discretion of the physician.Weaning time ranged from 13 to 167 h on average.Enteral clonidine was started in the prospective studies in a similar protocolized method,with 0.3 mg every 6 h.After starting clonidine,patients remained on dexmedetomidine for a median of 1-28 h.Following the termination of dexmedetomidine,two trials tapered enteral clonidine by increasing the interval every 24 h from 6 h to 8h,12h,and 24 h,followed by clonidine discontinuation.For indicators of enteral clonidine withdrawal,the previously tolerable dosage was reinstated for several days before resuming the taper on the same protocol.The adverse events associated with enteral clonidine use were higher than patients on dexmedetomidine taper alone with increased agitation.The re-initiation of dexmedetomidine was not documented in any study.Only 17(37%)patients were mechanically ventilated with median duration of 3.5 d for 13 patients in one of the 2 studies.ICU lengths of stay were similar.CONCLUSION Enteral clonidine is a strategy to wean critically ill patients from dexmedetomidine.There is an association of increased withdrawal symptoms and agitation with the use of a clonidine taper.

Dexmedetomidine mediates the mechanism of action of ferroptosis in mice with Alzheimer’s disease by regulating the mTOR-TFR1 pathway

BACKGROUND Alzheimer’s disease(AD)is the most common neurodegenerative disorder,and there are currently no effective drugs to delay progression of the disease.Ferroptosis may play a vital part in AD,and is therefore receiving increasing attention by researchers.AIM To investigate the effects of dexmedetomidine(Dex)on ferroptosis in AD mouse hippocampus.METHODS Hippocampal neurons(HNs)HT22 were induced by amyloidβ-protein(Aβ)and both in vitro and in vivo AD mouse models were prepared via injections.The cellcounting kit-8 assay and immunofluorescence technique were adopted to determine cell proliferation activity and intracellular Fe2+levels,and the TBA method and microplate method were employed for malondialdehyde and glutathione measurements,respectively.Hippocampal tissue damage was determined using hematoxylin and eosin and Nissl staining.Mouse learning and memory ability in each group was assessed by the Morris water maze test,and the expression levels of mammalian target of rapamycin(mTOR)signal molecules and ferroptosis-related proteins transferrin receptor 1(TFR1),SLC7A11 and glutathione peroxidase 4 were examined by western blotting.RESULTS Dex enhanced lipid peroxidation and iron influx in mouse HNs in both in vitro and in vivo experiments,while inhibition of the mTOR axis blocked this process.These findings demonstrate that Dex can inhibit ferroptosis-induced damage in mouse HNs by activating mTOR-TFR1 signaling to regulate ferroptosis-associated proteins,thus alleviating cognitive dysfunction in AD mice.CONCLUSION Dex can activate the mTOR-TFR1 axis to inhibit ferroptosis in mouse HNs,thereby improving the learning and memory ability of mice.

持续输注超低剂量右美托咪定对老年CAS患者血流动力学和术后认知功能的影响

目的探讨持续输注超低剂量右美托咪定对行颈动脉支架置入术(CAS)的老年患者血流动力学稳定性和术后认知功能的影响。方法选取106例于首都医科大学附属北京世纪坛医院择期行CAS的老年患者,随机分为右美托咪定组(D组,n=52)和对照组(C组,n=54)。观察2组患者麻醉诱导前15 min(T0)、麻醉诱导后5 min(T1)、置入支架前5 min(T2)、置入支架后5 min(T3)、气管拔管后5 min(T4)的血流动力学和脑灌注变化;计算平均动脉压(MAP)、心率(HR)和脑氧饱和度(rSO_(2))的标准差(SD),分别记作SD_(MAP)、SD_(HR)和SD_(rSO_(2))。应用蒙特利尔认知评估量表(MoCA)对患者进行认知功能评估,比较患者术前、术后认知功能的变化,评价2组患者术后认知功能障碍(POCD)的发生情况。结果D组患者SD_(MAP)、SD_(HR)和SD_(rSO_(2))均明显低于C组(P<0.05);D组麻醉药及血管活性药使用量明显低于C组(P<0.05);D组拔管时间明显短于C组(P<0.05);D组术后1 d MoCA评分明显高于C组,术后30 d POCD发生率明显低于C组(P<0.05)。结论持续输注超低剂量右美托咪定可维持血流动力学和脑灌注稳定,减少麻醉药物用量,促进术后认知功能恢复。

右美托咪定辅助全身麻醉对老年无痛肠镜检查患者血流动力学及认知功能的影响

目的探讨右美托咪定(DEX)辅助全身麻醉对老年无痛肠镜检查患者血流动力学及认知功能的影响。方法将2020年7月至2022年2月在焦作市第二人民医院门诊手术室行无痛肠镜检查的老年患者180例,根据随机数字表法分为对照组(n=90)和观察组(n=90)。对照组患者给予常规全身麻醉(舒芬太尼+丙泊酚麻醉诱导,丙泊酚麻醉维持);观察组患者在术前准备后加用DEX辅助全身麻醉。比较2组患者的血流动力学指标[平均动脉压(MAP)、心率(HR)]、全麻用药量、苏醒时间、认知功能[简易精神状况检查量表(MMSE)]评分、不良反应发生率。结果2组患者麻醉前(T0)各项指标的差异均无统计学意义(P>0.05);与T0时比较,麻醉10 min后(T1)、肠镜达回盲部(T2)、检查后退镜(T3)、术后10 min(T4)时两组患者的MAP、HR均显著降低,但观察组患者在T1、T2、T3、T4时的MAP、HR均显著高于对照组(P<0.05)。与对照组比较,观察组患者的全麻用药量显著降低,苏醒时间显著缩短,术后1、2、3 d的MMSE评分显著升高,认知功能障碍发生率及不良反应发生率均显著降低(P<0.05)。结论DEX可有效改善老年无痛肠镜检查患者的血流动力学及认知功能,减少全麻用药量,缩短患者苏醒时间,且安全性较好。

小剂量右美托咪定联合瑞马唑仑对蛛网膜下腔阻滞手术患者术中镇静效果观察

目的比较单纯瑞马唑仑和小剂量右美托咪定联合瑞马唑仑持续泵注的辅助镇静效果,探讨瑞马唑仑联合用药方法。方法选取2023年1~5月昆山市中医医院择期椎管内麻醉下肢手术患者50例,ASA分级Ⅰ或Ⅱ级、采用随机数字表法将患者分为对照组(C组,n=25)和试验组(S组,n=25),C组持续泵注瑞马唑仑0.3 mg/(kg·h)至术毕;S组持续泵注右美托咪定1.2μg/(kg·h),20 min后下调至0.4μg/(kg·h),同时泵注瑞马唑仑0.3 mg/(kg·h),20 min后下调至0.2 mg/(kg·h)。观测并记录患者在入室后10 min(T_(0))和静脉给药后10 min(T_(1))、20 min(T_(2))、45 min(T_(3))、60 min(T_(4))、术中(T_(5))、术毕(T_(6))的循环改变。观察并记录镇静起效、出现浅睡眠、出现深睡眠的时间和脑电双频谱指数(BIS)值,术中最低BIS值和Ramsay评分;观察记录停药后BIS值回升情况及苏醒时间;分别在患者入室后、患者出现浅睡眠和深睡眠时、手术结束时采集中心静脉血气,分析和比较中心静脉血氧饱和度(ScvO_(2))、中心静脉血二氧化碳分压(PcvCO_(2));统计术中不良反应。结果C组和S组镇静起效时间分别为(10.14±3.33)min、(9.32±2.62)min,差异无统计学意义(P>0.05),S组出现浅睡眠和深睡眠的时间较C组明显缩短,差异有统计学意义(P<0.05)。S组患者深度睡眠时BIS值和术中最低BIS值均低于C组,术中Ramsay镇静评分高于C组,差异有统计学意义(P<0.05);停药后5 min、10 min、15 min,S组患者的BIS值均低于C组,差异有统计学意义(P<0.01)。停药后10 min,S组苏醒12例,C组苏醒22例,差异有统计学意义(P<0.01)。与T_(0)比较,浅睡眠、熟睡时和手术结束时2组患者的PcvCO_(2)、ScvO_(2)和PcvCO_(2)均升高(P<0.01);组间比较,熟睡时S组ScvO_(2)和PcvCO_(2)高于C组,差异有统计学意义(P<0.05)。C组出现呛咳、烦躁等不良反应4例,6例患者全程警觉状态,S组无不良反应。结论持续泵注小剂量右美托咪定联合瑞马唑仑,镇静效果平稳、可靠,术中循环稳定,术毕苏醒平稳,不良反应少;不同镇静深度的临床表现特征明显,依据Ramsay评分及时调整静脉注射速度,可安全地应用于蛛网膜下腔阻滞手术患者术中辅助镇静。

右美托咪定通过下调Dectin-1表达抑制免疫细胞浸润保护缺血/再灌注损伤的心肌

目的:探索右美托咪定(Dex)保护缺血/再灌注(I/R)诱导的心肌损伤的分子机制。方法:小鼠在体实验分组如下:野生型小鼠对照(Control)组、假手术(Sham)组、野生型小鼠缺血/再灌注模型(WT I/R)组和Dex预处理(WT Dex)组,Dectin-1基因敲除小鼠缺血/再灌注模型(KO I/R)组和Dex预处理(KO Dex)组,每组6只。TTC染色并测定小鼠心脏梗死区域(%),HE染色和病理学分析小鼠心肌损伤情况,ELISA测定小鼠血清TNF-α、IL-6和IL-10的水平,流式细胞术(FCM)计数和分选小鼠心肌浸润M2巨噬细胞和中性粒细胞,qPCR测定上述分选细胞中Dectin-1 mRNA表达情况。结果:TTC结果显示Control组和Sham组小鼠心肌未发生梗死;与WT I/R组相比,WT Dex组、KO I/R组和KO Dex组小鼠心肌梗死体积显著减少(P<0.05)。与KO I/R组相比,KO Dex组小鼠心肌梗死体积也明显减小(P<0.05)。HE染色结果显示WT I/R组小鼠心肌排列杂乱,出现大量断裂心肌纤维,WT Dex组、KO I/R组和KO Dex组小鼠心肌纤维存在少许断裂的情况,结构破坏不显著,心肌排列较为整齐;KO Dex组小鼠心肌损伤程度小于KO I/R组。ELISA结果显示,与Sham组相比,WT I/R组小鼠血清TNF-α和IL-6水平显著升高,IL-10水平显著降低;与WT I/R组相比,WT Dex组和KO I/R组小鼠血清TNF-α和IL-6水平显著降低,IL-10水平显著升高;与KO I/R组相比,KO Dex组小鼠血清TNF-α和IL-6水平显著降低,IL-10水平显著升高(P<0.05)。FCM结果显示,与Sham组相比,WT I/R组小鼠心肌浸润大量M2巨噬细胞和中性粒细胞(P<0.05);与WT I/R组相比,WT Dex组、KO I/R组和KO Dex组小鼠心肌浸润的M2巨噬细胞和中性粒细胞显著降低(P<0.05);KO I/R组和KO Dex组之间差异无统计学意义(P>0.05)。qPCR结果显示,与Sham组相比,WT I/R组小鼠心肌浸润的M2巨噬细胞和中性粒细胞中Dectin-1 mRNA表达量显著上调(P<0.05);与WT I/R组相比,Dex组则显著降低(P<0.05);KO I/R组和KO Dex组小鼠不表达Dectin-1。结论:Dex预处理对I/R损伤心肌的保护机制涉及降低I/R后小鼠心肌浸润的M2巨噬细胞和中性粒细胞数量,这一过程可能是通过抑制Dectin-1的表达来实现的。

极低剂量右美托咪定对老年患者全身麻醉苏醒期呛咳的影响

目的探讨极低剂量右美托咪定对老年患者颈动脉支架置入术(CAS)全身麻醉苏醒期呛咳的影响。方法选择择期行CAS的无症状单侧重度颈动脉狭窄老年患者111例,男75例,女36例,年龄≥65岁,BMI 18~32 kg/m^(2),ASAⅡ或Ⅲ级。采用随机数字表法将患者分为两组:右美托咪定组(D组,n=55)和对照组(C组,n=56)。D组于麻醉诱导前给予右美托咪定0.2~0.5μg/kg,麻醉诱导后至手术结束前30 min静脉输注极低剂量右美托咪定0.1~0.2μg·kg^(-1)·h^(-1);C组不给予右美托咪定。两组麻醉方案及术中用药方案相同。记录麻醉诱导前15 min(T_(0))、麻醉诱导后5 min(T_(1))、支架置入前5 min(T_(2))、支架置入后5 min(T_(3))、气管拔管后5 min(T_(4))的MAP和HR。记录术中丙泊酚和瑞芬太尼用量、麻醉苏醒期呛咳、躁动、呼吸抑制(SpO_(2)<90%)、拔管时间以及术后穿刺处感染、术后24 h VAS疼痛评分、术后恶心呕吐的发生情况。结果与C组比较,D组T_(1)、T_(2)时MAP明显升高,T_(3)、T_(4)时MAP明显降低,T_(1)、T_(3)、T_(4)时HR明显减慢(P<0.05),术中丙泊酚和瑞芬太尼用量明显减少(P<0.05),麻醉苏醒期呛咳、躁动发生率明显降低(P<0.05)。两组呼吸抑制发生率、拔管时间、术后24 h VAS疼痛评分以及术后恶心呕吐发生率差异无统计学意义,两组均未发生术后穿刺处感染。结论极低剂量右美托咪定可有效维持术中血流动力学稳定性,降低麻醉苏醒期呛咳、躁动发生率,且不增加术后不良反应,提高全身麻醉苏醒质量。

右美托咪定对腹腔镜肾部分切除术患者远期肾功能的保护作用

目的观察右美托咪定(DEX)对腹腔镜肾部分切除术(LPN)患者术后远期肾功能的保护作用。方法选取2021年5月至2022年12月安徽医科大学第二附属医院择期行LPN患者80例,根据随机对照表法将患者随机分为右美托咪定组和对照组,每组40例。右美托咪定组在肾动脉阻断前30 min给予DEX负荷量0.6 mg/kg,之后改为维持剂量0.5μg/(kg·h)并持续到手术结束前30 min。对照组静脉泵注相同剂量和时间的生理盐水。记录患者麻醉诱导前(T_(0))、插管即刻(T_(1))、肾动脉阻断即刻(T_(2))、肾动脉开放即刻(T_(3))和拔管即刻(T_(4))的平均动脉压(MAP)和心率(HR)。监测患者术前以及术后1、6个月^(99m)Tc-DTPA肾小球滤过率(GFR)、血清胱抑素C(Cys-C)和血清肌酐(SCr),并根据公式计算出基于SCr的估计GFR(eGFRcr)、基于SCr和Cys-C的估计GFR(eGFRcr-cys)和基于Cys-C的估计GFR(eGFRcys)。观察患者术前以及术后24 h和48 h血清中性粒细胞明胶酶相关载脂蛋白(NGAL)和尿肾损伤分子-1(KIM-1)含量。结果T_(1)、T_(4)时,右美托咪定组MAP低于对照组(P<0.05),T_(2)时,MAP高于对照组(P<0.05);T_(1)时,右美托咪定组HR低于对照组(P<0.05)。术后24 h和48 h,右美托咪定组血清NGAL和尿KIM-1低于对照组(P<0.05)。术后1、6个月,右美托咪定组手术侧^(99m)Tc-DTPA GFR值高于对照组(P<0.05),而两组对侧^(99m)Tc-DTPA GFR和总^(99m)Tc-DTPA GFR值比较,差异无统计学意义(P>0.05)。术后1、6个月,右美托咪定组eGFRcr-cys和eGFRcys值高于对照组(P<0.05),但两组eGFRcr值比较,差异无统计学意义(P>0.05)。结论DEX可对LPN术后远期肾功能产生保护作用,是防治LPN术后慢性肾脏病发生和发展的潜在治疗药物。