Anesthesia,Anesthetics,and Postoperative Cognitive Dysfunction in Elderly Patients

Postoperative cognitive dysfunction(POCD)remains a major issue that worsens the prognosis of elderly surgery patients.This article reviews the current research on the effect of different anesthesia methods and commonly utilized anesthetics on the incidence of POCD in elderly patients,aiming to provide an understanding of the underlying mechanisms contributing to this condition and facilitate the development of more reasonable anesthesia protocols,ultimately reducing the incidence of POCD in elderly surgery patients.

Inhaled volatile anesthetics in the intensive care unit

The discovery and utilization of volatile anesthetics has significantly transformed surgical practices since their inception in the mid-19th century.Recently,a paradigm shift is observed as volatile anesthetics extend beyond traditional confines of the operating theatres,finding diverse applications in intensive care settings.In the dynamic landscape of intensive care,volatile anesthetics emerge as a promising avenue for addressing complex sedation requirements,managing refractory lung pathologies including acute respiratory distress syndrome and status asthmaticus,conditions of high sedative requirements including burns,high opioid or alcohol use and neurological conditions such as status epilepticus.Volatile anesthetics can be administered through either inhaled route via anesthetic machines/devices or through extracorporeal membrane oxygenation circuitry,providing intensivists with multiple options to tailor therapy.Furthermore,their unique pharmacokinetic profiles render them titratable and empower clinicians to individualize management with heightened accuracy,mitigating risks associated with conventional sedation modalities.Despite the amounting enthusiasm for the use of these therapies,barriers to widespread utilization include expanding equipment availability,staff familiarity and training of safe use.This article delves into the realm of applying inhaled volatile anesthetics in the intensive care unit through discussing their pharmacology,administration considerations in intensive care settings,complication considerations,and listing indications and evidence of the use of volatile anesthetics in the critically ill patient population.

Comparative studies on the binding site of anesthetics to GABA a receptors using in silico docking methods

Although the GABAA receptor(GABAAR)has been proposed as the main action site for sevoflurane,isoflurane,halothane,enflurane,propofol,and benzodiazepines(BZDs),binding of these anesthetics with high-resolution structures of the GABAAR have been rarely examined by comparative docking analyses.Moreover,various combinations of ligands on more GABAARs with various subtypes need to be analyzed to understand the elaborate action mechanism of GABAARs better because some GABAA ligands showed specificity toward the distinct subtypes of the GABAAR.Methods:We performed in silico docking analysis to compare the binding modes of sevoflurane,isoflurane,halothane,enflurane,propofol,and BZDs to the GABAAR based on one of the most recently provided 3D structures.We performed the docking analysis and the affinity-based ranking of the binding sites.Results:Our docking studies revealed that isoflurane,halothane,and enflurane docked in an extracellular domain(ECD)on GABAARs,in contrast to sevoflurane.Conclusion:Our results supported a multi-site mechanism for the allosteric modulation of propofol.Propofol was bound to the pore or favored various subsites in the transmembrane domain(TMD).Our result confirmed that different chemically related BZD ligands interact via distinct binding modes rather than by using a common binding mode,as previously suggested.

Adjuvants to local anesthetics: Current understanding and future trends

Although beneficial in acute and chronic pain management, the use of local anaesthetics is limited by itsduration of action and the dose dependent adverse effects on the cardiac and central nervous system. Adjuvants or additives are often used with local anaesthetics for its synergistic effect by prolonging the duration of sensory-motor block and limiting the cumulative dose requirement of local anaesthetics. The armamentarium of local anesthetic adjuvants have evolved over time from classical opioids to a wide array of drugs spanning several groups and varying mechanisms of action. A large array of opioids ranging from morphine, fentanyl and sufentanyl to hydromorphone, buprenorphine and tramadol has been used with varying success. However, their use has been limited by their adverse effect like respiratory depression, nausea, vomiting and pruritus, especially with its neuraxial use. Epinephrine potentiates the local anesthetics by its antinociceptive properties mediated by alpha-2 adrenoreceptor activation along with its vasoconstrictive properties limiting the systemic absorption of local anesthetics. Alpha 2 adrenoreceptor antagonists like clonidine and dexmedetomidine are one of the most widely used class of local anesthetic adjuvants. Other drugs like steroids(dexamethasone), anti-inflammatory agents(parecoxib and lornoxicam), midazolam, ketamine, magnesium sulfate and neostigmine have also been used with mixed success. The concern regarding the safety profile of these adjuvants is due to its potential neurotoxicity and neurological complications which necessitate further research in this direction. Current research is directed towards a search for agents and techniques which would prolong local anaesthetic action without its deleterious effects. This includes novel approaches like use of charged molecules to produce local anaesthetic action(tonicaine and n butyl tetracaine), new age delivery mechanisms for prolonged bioavailability(liposomal, microspheres and cyclodextrin systems) and further studies with other drugs(adenosine, neuromuscular blockers, dextrans).

Effect of Inhalational Anesthetics on Cytotoxicity and Intracellular Calcium Differently in Rat Pheochromocytoma Cells (PC12)

Isoflurane, a commonly used inhaled anesthetic, induces apoptosis in rat pheochromocytoma cells （PC12） in a concentration- and time-dependent manner with unknown mechanism. We hypothesized that isoflurane induced apoptosis by causing abnormal calcium release from the endoplasmic reticulum （ER） via activation of inositol 1,4,5-trisphosphate （IP3） receptors. Alzheimer＇s presenilin-1 （PS 1） mutation increased activity of IP3 receptors and therefore rendered cells vulnerable to isoflurane-induced cytotoxicity. Sevoflurane and desflurane had less ability to disrupt intracellular calcium homeostasis and thus being less potent pared the cytotoxic effects of various inhaled to cause cytotoxicity. This study examined and com-anesthetics on PC12 cells transfected with the Alzheimer＇s mutated PS 1 （L286V） and the disruption of intracellular calcium homeostasis. PC 12 cells transfected with wild type （WT） and mutated PS 1 （L286V） were treated with equivalent of 1 MAC of isoflurane, sevoflurane and desflurane for 12 h. MTT reduction and LDH release assays were performed to evaluate cell viability. Changes of calcium concentration in cytosolic space （[Ca^2＋]c） were determined after exposing different types of cells to various inhalational anesthetics. The effects of IP3 receptor antagonist xestospongin C on isoflurane-induced cytotoxicity and calcium release from the ER in L286V PC12 cells were also determined. The results showed that isoflurane at 1 MAC for 12 h induced cytoxicity in L286V but not WT PC12 cells, which was also associated with greater and faster elevation of peak [Ca^2＋]c in L286V than in the WT cells. Xestospongin C significantly ameliorated isoflurane cytotoxicity in L286V cells, as well as inhibited the calcium release from the ER in L286V cells. Sevoflurane and desflurane at equivalent exposure to isoflurane did not induce similar cytotoxicity or elevation of peak [Ca^2＋]c in L286V PC 12 cells. These results suggested that isoflurane induced cytoxicity by partially causing abnormal calcium release from the ER via activation of IP3 receptors in L286V PC12 cells. Sevoflurane and desflurane at equivalent exposure to isoflurane did not induce similar elevation of [Ca^2＋]c or neurotoxicity in PC 12 cells transfected with the Alzheimer＇s PS 1 mutation.

Why Labor Epidural Causes Fever and Why Lidocaine Burns on Injection? Role of TRPV 1 Receptor in Hyperthermia: Possible Explanation of Mechanism of Hyperthermia during Labor Epidural and Burning Sensation on Injection of Local Anesthetics

The mechanisms of epidural-associated fever remain incompletely understood [1-3]. We propose that action of local anesthetic on TPRV1. The transient receptor potential cation channel subfamily V member 1 (TRPV1), also known as the capsaicin receptor and the vanilloid receptor can explain this effect and explain mechanism of burning sensation on local anesthetic injected subcutaneously or intramuscular. Role of TRPV1 receptor was not discussed previously in Obstetric Anesthesia literature. Based on available data, we propose that Local Anesthetics work as agonist/antagonist on TPRV1 receptors. Antagonist action may cause hyperthermia through modifying thermoregulation [4], agonist action may cause hyperthermia thru release of IL-6 and other mediators of inflammation [5-10]. Agonist action may explain burning sensation on injection of Local Anesthetics. Burning sensation can be diminished by increasing pH of Local Anesthetic solution, because vanillin receptors are stimulated by acidification through lower pH [11,12].

Anesthetic Action of Volatile Anesthetics by Using Paramecium as a Model

Although empirically well understood in their clinical administration, volatile anesthetics are not yet well comprehended in their mechanism studies. A major conundrum emerging from these studies is that there is no validated model to assess the presumed candidate sites of the anesthetics. We undertook this study to test the hypothesis that the single-celled Paramecium could be anesthetized and served as a model organism in the study of anesthetics. We assessed the motion of Paramecium cells with Expert Vision system and the chemoresponse of Paramecium cells with T-maze assays in the presence of four different volatile anesthetics, including isoflurane, sevoflurane, enflurane and ether. Each of those volatiles was dissolved in buffers to give drug concentrations equal to 0.8, 1.0, and 1.2 EC50, respectively, in clinical practice. We could see that after application of volatile anesthetics, the swimming of the Paramecium cells was accelerated and then suppressed, or even stopped eventually, and the index of the chemoresponse of the Paramecium cells （denoted as Iche） was decreased. All of the above impacts were found in a concentration-dependent fashion. The biphasic effects of the clinical concentrations of volatile anesthetics on Paramecium simulated the situation of high species in anesthesia, and the inhibition of the chemoresponse also indicated anesthetized. In conclusion, the findings in our studies suggested that the single-celled Paramecium could be anesthetized with clinical concentrations of volatile anesthetics and therefore be utilized as a model organism to study the mechanisms of volatile anesthetics.

Analysis of the Effect of Anesthetics Comprising of Remifentanil Combined with Propofol During Thyroidectomy

Objective:To analyze the anesthetic effect of remifentanil combined with propofol during thyroidectomy.Methods:A total of 70 patients who underwent thyroidectomy during November 2018 to November 2019 in Chongqing Eleventh People’s Hospital were selected and recruited.These patients were divided into control group and observation group by random number table method.Each group consisted of 35 patients.The patients in the control group was given intravenous anesthesia comprising of propofol combined with intermittent fentanyl anesthesia,whereas the patients in the observation group was given intravenous anesthesia comprising of remifentanil combined with propofol.Results:The heart rate and mean arterial pressure of the observation group after anesthesia for 30 minutes were lower than those of the control group,and the differences were statistically significant(P<0.05).The total incidence of adverse reactions in the observation group was lower than that of the control group,and the differences were statistically significant(P<0.05).Conclusion:Remifentanil combined with propofol is effective in thyroidectomy.This combination can reduce the risk of adverse reactions and maintain stable hemodynamic parameters.

Neuroendocrine,epigenetic,and intergenerational effects of general anesthetics

The progress of modern medicine would be impossible without the use of general anesthetics(GAs).Despite advancements in refining anesthesia approaches,the effects of GAs are not fully reversible upon GA withdrawal.Neurocognitive deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the elderly.Human studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research,but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such effects.The latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents,which are far more extensively studied than any other species.Our most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently anticipated.Specifically,we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities(somatic effects),but also epigenetic reprogramming of germ cells(germ cell effects).The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring,who may be affected even at levels of anesthesia that are not harmful to the exposed parents.The large number of patients who require general anesthesia,the even larger number of their future unexposed offspring whose health may be affected,and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of GAs.In this mini review,we discuss emerging experimental findings on neuroendocrine,epigenetic,and intergenerational effects of GAs.

Different Volumes of Local Anesthetics in Ultrasound-Guided Combined Interscalene-Supraclavicular Block for Traumatic Humeral Fracture

Background: Procedures that require anesthesia of entire length of the arm should have combined Interscalene block (ISB) and Supraclavicular block (SCB) to ensure adequate block. However, dual block requires high dose of local anesthetic (LA). We examined if Ultrasound (U/S) guided block helps to decrease the required volume of LA by visualizing trunks, so we only need injection of LA toward cervical nerve roots C5 and C6 aiming to block branches escaped from supraclavicular block. Patients and methods: Ninety-three patients were randomly allocated into one of three equal groups, each included 31 patients. All patients received SCB 20 ml (10 ml Bupivacaine 0.5% plus 10 ml lidocaine 2%) and ISB with different volumes of LA according to the group as follow: group A: 20 ml, group B: 15 ml, and group C: 10 ml. Result: No significant difference in onset of block (sensory and motor) and duration of block (motor only) between the three groups (P value > 0.05). The duration of sensory block was significantly longer in group A (760.65 ± 30.87 minutes) than in either group B (740.48 ± 21.15 minutes, P value P value P value P value P value P value < 0.001). Conclusion: A reduced volume of LA can be used in ultra sound guided ISB in combined with SCB to give satisfactory level of anesthesia to entire length of the arm, but the sensory block duration and duration of post-operative analgesia will be decreased significantly with decreasing the volume.

Toxic keratopathy associated with abuse of topical anesthetics and amniotic membrane transplantation for treatment

AIMTo evaluate the clinical findings of toxic keratopathy associated with abuse of topical anesthetics and the treatment efficacy of amniotic membrane transplantation (AMT).METHODSFifteen eyes of 10 patients with abuse of topical anesthetics were included in this study. The data collected included patients' demographic information, initial best corrected visual acuity (BCVA), clinical findings, time to AMT, duration of epithelization, additional treatments, posttreatment BCVA, and the results of psychiatric examination.RESULTSAll patients were male, with the mean age of 37.9&#x000b1;5.4y. The patients had received 0.5% proparacaine hydrochloride due to pain resulting from foreign bodies, such as welding flash burns and car battery explosions, for a mean of 18.2&#x000b1;12.4d. The mean initial BCVA of the patients was 0.069&#x000b1;0.100. All patients had persistent epithelial defects, stromal infiltration, ring ulcer, and corneal edema. Initially, medical treatment was attempted in all cases. Because of severe pain, persistent epithelial defects and progressing stromal thinning did not improve with medical treatment, thus, the patients underwent AMT. The mean posttreatment BCVA of the patients was 0.33&#x000b1;0.27. All of them, except for two patients, showed improved visual acuity. One patient underwent evisceration for corneal melting and endophthalmitis in another center, and one patient underwent evisceration for severe pain of unknown origin. All 5 patients who consented to a psychiatric examination had depression, had personality disorder, and used tobacco.CONCLUSIONAMT appears to be an effective method for pain relief, rapid epithelial and stromal healing; however, visual prognosis is still poor despite medical and surgical interventions.

Designing General Anesthetics That Have a Better Safety Profile

General anesthetics constitute some of the most important and widely-used therapeutic drugs in the pharmacotherapeutic armamentarium. They are routinely used effectively and with adequate precaution-safety throughout the world for a multitude of clinical applications, predominantly as adjunctive agents for surgical procedures. Nevertheless, they have potential adverse effects (such as a drop in blood pressure and the inhibition of steroid production), particularly in vulnerable populations such as the very young and the frail elderly. It would be desirable therefore to have alternative agents that are just as efficacious, but have a better safety profile in a broader spectrum of patients. Toward this end, an anesthetic based on a unique chemical core (viz., an N-arylpyrrole derivative) has been reported in preclinical models to produce anesthetic effects without hemodynamic suppression. This lead could pave the way for new general anesthetics that are safer and easier to use.

Study of physisorption of volatile anesthetics on phos-pholipid monolayers using a highly sensitive quartz crystal microbalance (HS-QCM)

We have investigated the interactions between phospholipid monolayers and volatile anest-hatics. Two monolayers (dihexadecyl phosphate (DHP) and dipalmitoyl phosphatidyl choline (DPPC) and two anesthetics (halothane and enflurane) were used to observe these interac-tions using a highly sensitive quartz crystal microbalance (HS-QCM). The concentration of each anesthetic in aqueous solution was kept at 4 mM. The frequency of QCM showed no change when halothane was added to the DHP monolayer, however, it responded and de-creased when interaction occurred with DPPC monolayer. In case of enflurane addition the frequency decreased in both the monolayers of DHP and DPPC. The frequency change followed the following order of monolayer-anesthetic interactions: DHP-halothane <DPPC-halothane <DHP-enflurane <DPPC-enflurane. These re-sults showed that the response of anesthetics to the monolayers i.e. the physisorption not only depends on the anesthetic structure, the type of anesthetic hydrate formed, but also the hydrophilic polar group structure of the monolayer or the monolayer/water interface had an important role in physisorption.

Development of three Drosophila melanogaster strains with different sensitivity to volatile anesthetics

Background The mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved. Methods Median effective doses （ED50） of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6-10 were cultured for breeding sensitive offspring （$1）. So did median ones of percentile 48-52 for breeding median offspring （M1）, resistant ones of percentile 91-95 for breeding resistant offspring （R1）. Process was repeated through 31 generations, in the 37th generation, S37, M37 and R37 were used to determine ED5o for enflurane, isoflurane, sevoflurane, desfiurane, halothane, methoxyflurane, chloroform and trichloroethylene, then ED50 values were correlated with minimum alveolar concentration （MAC） values in human. Results From a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20：1.00：0.53 for females and 1.22：1.00：0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED50 values in three strains correlated directly with MAC values in human. Conclusions Three Drosophila melanogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED50 are directly correlated with MAC in human for eight volatile anesthetics.

Volatile anesthetics inhibit the activity of calmodulin by interacting with its hydrophobic site

Background Volatile anesthetics （VAs） may affect varied and complex physiology processes by manipulating Ca2＋-calmodulin （CAM）. However, the detailed mechanism about the action of VAs on CaM has not been elucidated. This study was undertaken to examine the effects of VAs on the conformational change, hydrophobic site, and downstream signaling pathway of CaM, to explore the possible mechanism of anesthetic action of VAs. Methods Real-time second-harmonic generation （SHG） was performed to monitor the conformational change of CaM in the presence of VAs, each plus 100 μmol/L Ca2＋. A hydrophobic fluorescence indicator, 8-anilinonaphthalene-l-sulfonate （ANS）, was utilized to define whether the VAs would interact with CaM at the hydrophobic site or not. High-performance liquid chromatography （HPLC） was carried out to analyze the activity of CaM-dependent phosphodiesterase （PDE1） in the presence of VAs. The VAs studied were ether, enflurane, isoflurane, and sevoflurane, with their aqueous concentrations 7.6, 9.5, 11.4 mmol/L; 0.42, 0.52, 0.62 mmol/L; 0.25, 0.31, 0.37 mmol/L and 0.47, 0.59, 0.71 mmol/L respectively, each were equivalent to their 0.8, 1.0 and 1.2 concentration for 50% of maximal effect （EC50） for general anesthesia. Results The second-harmonic radiation of CaM in the presence of Ca2＋ was largely inhibited by the VAs. The fluorescence intensity of ANS, generated by binding of Ca2＋ to CaM, was reversed by the VAs. HPLC results also showed that AMP, the product of the hydrolysis of cAMP by CaM-dependent PDE1, was reduced by the VAs. Conclusions Our findings demonstrate that the above VAs interact with the hydrophobic core of Ca2＋-CaM and the interaction results in the inhibition of the conformational change and activity of CaM. This in vitro study may provide us insight into the possible mechanism of anesthetic action of VAs in vivo.

Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection

BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer.However,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this procedure.AIM To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric cancer.METHODS A total of 80 patients were involved in this research.The subjects were divided into two groups:Propofol group and sevoflurane group.The evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(SAS)and self-rating depression scale(SDS).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also measured.RESULTS The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane group.Additionally,the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol group.The sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol group.Moreover,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol group.CONCLUSION Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric cancer.Propofol anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative recovery.Sevoflurane anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental state.Therefore,the selection of anesthetic agents should be based on the individual patient's specific circumstances.

Nurse anesthetists’perceptions and experiences of managing emergence delirium:A qualitative study

BACKGROUND This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium(ED),a common and complex postoperative complication in the post-anesthesia care unit.The role of nurses in managing ED is critical,yet research on their understanding and management strategies for ED is lacking.AIM To investigate anesthetic nurses’cognition and management experiences of ED in hopes of developing a standardized management protocol.METHODS This study employed a descriptive phenomenological approach from qualitative research methodologies.Purposeful sampling was utilized to select 12 anesthetic nurses from a tertiary hospital in Shanghai as research subjects.Semi-structured interviews were conducted,and the data were organized and analyzed using Colaizzi’s seven-step analysis method,from which the final themes were extracted.RESULTS After analyzing the interview content,four main themes and eight subthemes were distilled:Inefficient cognition hinders the identification of ED(conceptual ambiguity,empirical identification),managing diversity and challenges(patientcentered safe care,low level of medical-nursing collaboration),work responsibilities and pressure coexist(heavy work responsibilities,occupational risks and stress),demand for high-quality management(expecting the construction of predictive assessment tools and prevention strategies,and pursuing standardized management processes to enhance management effectiveness).CONCLUSION Nursing managers should prioritize the needs and suggestions of nurses in order to enhance their nursing capabilities and provide guidance for standardized management processes.

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.

Anesthetic effect of phenobarbital sodium on female BALB/c mice

Objective:Anesthetics are of great importance in avoiding severe pain and suffering in animals and ensuring experimental progress.This study was aimed at elucidating the anesthesia score of phenobarbital sodium as a general anesthetic at different concentrations and doses in BALB/c mice,and finding the suitable anesthesia strategies for experimental surgeries.Methods:Phenobarbital sodium was administrated intraperitoneally at the doses of 75,100,125,150,and 200 mg/kg and randomly in different concentrations(2%,5%,and 10%)to female BALB/c mice.The anesthesia score was evaluated based on the stimulus index including tail-pinch,front and hind limb withdrawal,and eyelid reflexes.The speed and duration of anesthesia in different groups were recorded per the occurrence and duration of the righting reflex.Results:The anesthetic effect of phenobarbital sodium on female BALB/c mice showed an obvious dose-dependency.Respiratory suppression caused by high-dose anesthesia may lead to mouse death.Based on the anesthesia score,when the phenobarbital sodium treatment was greater than or equal to five percent or 200 mg/kg,more than 80%mice meet the anesthesia depth that surgical operation needed.The rates of achieving surgical anesthesia depth(standard-reaching rate)in mice treated with 2%sodium phenobarbital were 0%in the 75 mg/kg group,0%in the 100 mg/kg group,50%in the 125 mg/kg group,66.7%in the 150 mg/kg group,and 100%in the 200 mg/kg group.The standard-reaching rate of mice treated with 5%concentration of phenobarbital sodium were:0%in the 75 mg/kg group,0%in the 100 mg/kg group,83.33%in the 125 mg/kg group,100%in the 150 mg/kg group,and 100%in the 200 mg/kg group.The standard-reaching rate of mice treated with 10%concentration of phenobarbital sodium were:50%in the 75 mg/kg group,66.7%in the 100 mg/kg group,100%in the 125 mg/kg group,100%in the 150mg/kg group,and 100%in the 200 mg/kg group.Sedation and hypnosis were induced in the low-concentration dose group,and anesthesia was induced in the high-concentration dose group.In the 5%and 125 mg/kg phenobarbital sodium groups,the mortality rate of mice was 0,the anesthesia induction time was(35.5±7.92)minutes,and the anesthesia duration was(106±39.59)minutes.In the 5%and 150 mg/kg phenobarbital sodium groups,the mortality rate of mice was 0,the anesthesia induction time was(34.83±5.27)minutes,and the anesthesia duration was(131.7±36.75)minutes.Conclusion:Phenobarbital sodium alone can provide appropriate general anesthesia in female BALB/c mice.Both the concentration and dose of phenobarbital sodium can affect the anesthetic effect.On the basis of our findings,we recommend the 5%and 125 mg/kg and 5%and 150 mg/kg concentration–dose combinations of phenobarbital sodium for anesthetizing mice according to the surgical requirement.

全身麻醉经可视麻醉喉镜会厌囊肿切除术

会厌囊肿是耳鼻咽喉科常见疾病,严重者会有窒息危险,明确诊断后应尽早手术切除[1]。我科采用全身麻醉经可视麻醉喉镜会厌囊肿切除术,取得了良好效果。1.1临床资料。2013年4月~2014年3月我科就诊25例会厌囊肿患者,男11例,女14例,年龄27~65岁,平均年龄47.9岁,术前均常规检查排除手术及麻醉禁忌,喉动态镜检查了解会厌囊肿的位置、大小,术前准备完善。1.2方法。患者仰卧位,经鼻或经口气管插管,