Effects of dexmedetomidine, propofol, sevoflurane and S-ketamine on the human metabolome: A randomised trial using nuclear magnetic resonance spectroscopy

Effects of S-ketamine on recovery quality in elderly patients with impaired intrinsic capacity after total knee arthroplasty: a single-centre, randomised, double-blind, placebo-controlled study protocol

INTRODUCTION

Elderly patients with impaired intrinsic capacity are at increased risk for delayed or suboptimal recovery from surgery. S-ketamine has been proven to improve postoperative recovery quality. However, limited trials are studying the postoperative recovery quality in elderly patients with impaired intrinsic capacity. Therefore, the objective of this study was to evaluate the impact of S-ketamine on the quality of recovery in elderly patients with impaired intrinsic capacity following total knee arthroplasty.

METHODS AND ANALYSIS

This is a single-centre, randomised, double-blind, placebo-controlled trial. Participants undergoing total knee arthroplasty will be randomly assigned in a 1:1 ratio to either the S-ketamine group (n=80) or the placebo group (n=80). The S-ketamine group will undergo an intravenous infusion of S-ketamine administered at a dosage rate of 0.2 mg·kg⁻1·h⁻1 for 1 hour. The placebo group will receive an intravenous saline infusion at an identical rate and duration. Postoperatively, the S-ketamine group will continuously infuse S-ketamine for 48 hours using a patient-controlled intravenous device, with a fixed rate of 0.01 mg·kg⁻¹·h⁻¹, a bolus dose of 0.02 mg·kg⁻¹, a lockout period of 10 min and a maximum infusion rate of 0.13 mg·kg⁻¹·h⁻¹. In contrast, the patient-controlled intravenous device for the placebo group will not contain S-ketamine. The primary outcome is the quality of recovery scores at 24 hours following total knee arthroplasty. Secondary outcomes encompass quality of recovery scores at 48 and 72 hours postoperatively, pain scores at rest and during movement, oral morphine equivalents, sleep quality assessments, depression scores, the Barthel Index and the time to meet discharge criteria.

ETHICS AND DISSEMINATION

Approval for the trial was granted by the Medical Ethics Committee of The Affiliated Hospital of Qingdao University (QYFYEC2024-74). Written informed consent will be obtained from each patient before enrolment. The results of this trial will be presented at scientific conferences and in peer--reviewed scientific journals.

TRIAL REGISTRATION NUMBER

ChiCTR2400087028.

Unraveling the mechanisms of propofol-induced psychological dependence: a multi-omics approach linked to gut microbiota in hippocampal function

Introduction

Drug abuse is becoming a global public health crisis. According to the United Nations, the number of drug users worldwide has increased dramatically over the past decade, with a surge in the number of drug abusers. The problem was exacerbated by the expanding market for illicit drugs and the increasing availability of synthetic drugs such as fentanyl. Clinical drug abuse is a problem that requires particular attention, and the potential addictive properties of some drugs and their mechanisms of action are currently unknown, which limits the development and implementation of drug addiction intervention strategies.

Methods

Eight-week-old C57BL/6J mice were used as study subjects. A mental dependence model was established using the conditional position preference experiment (CPP), and the hippocampal tissues of the model mice were subjected to RNA-seq transcriptome sequencing, LC-MS non-targeted metabolome sequencing, and intestinal macro-genome sequencing in order to discover propofol mental dependence signature genes. Correlation analyses of transcriptomics and metabolomics were performed using the Spearman method, and gene-metabolite networks were mapped using Cytoscape software. Real-time fluorescence quantitative PCR and immunoprotein blotting (Western blotting) methods were used to validate the characterized genes.

Results

After the conditioned position preference experiment, the conditioned preference scores of the 75 mg/kg propofol and 2 g/kg alcohol groups were significantly higher than those of the control saline group. 152 differential genes and 214 differential metabolites were identified in the 75 mg/kg group. Cluster analysis revealed that changes in the neuroactive ligand receptor pathway were most pronounced. Gut microbiomics assays revealed significant changes in five differential enterobacterial phyla (Campylobacter phylum, Thick-walled phylum, Anaplasma phylum, Actinobacteria phylum, and Chlorella verticillata phylum) in the 75 mg/kg propofol group, which may be related to changes in the differential expression of dopamine.

Discussion

These findings suggest that 75 mg/kg propofol has a significant mind-dependent effect on the biology of drug addiction through neuroactive ligand-receptor interaction pathways in conjunction with the tricarboxylic acid cycle, and the metabolic pathways of alanine, aspartate, and glutamate that may influence intestinal microbial changes through bidirectional signaling.

Dexmedetomidine decreases cerebral hyperperfusion incidence following carotid stenting: A double-blind, randomized controlled trial

BACKGROUND

Cerebral hyperperfusion syndrome (CHS) is a severe complication after carotid artery stenting (CAS). Dexmedetomidine (Dex) is an α2 adrenoceptor agonist with sedative, analgesic, and neuroprotective properties. This randomized, double-blind, placebo-controlled trial (ChiCTR1900024416) aims to investigate whether prophylactic low-dose Dex decreases CH-induced brain injury following CAS.

METHODS

After obtaining written informed consent, patients aged 18-80 who underwent CAS were enrolled between July 2019 and October 2022. Patients were randomly assigned to receive either intravenous Dex (0.1 μg/kg/h, until post-operative day 3) (n = 80) or placebo (normal saline) (n = 80). The primary endpoint was the incidence of CH and CHS assessed up to the third post-operative day. The secondary endpoints included National Institute of Health Stroke Scale (NIHSS) and Modified Rankin Scale (mRS) scores within 30 days of operation, extubation time, discharge from the hospital within 7 days post-operation, length of hospital stay post-operation, and all-cause 30-day mortality. Blood samples were collected before and after surgery for lipidomics, brain-derived neurotrophic factor (BDNF), and neurofilament light chain (Nfl) measurements. Acceptability, safety, and efficacy were evaluated by Cox model and logistic model.

FINDINGS

CH occurred in 30 (37.5%) of 80 patients who received a placebo compared to 9 (11.2%) of 80 patients given Dex (prevalence: odds ratio [OR]: 0.21, 95% confidence interval [CI]: 0.088-0.467; p < 0.001; incidence: hazard ratio [HR]: 0.27, 95% CI: 0.14-0.50; p < 0.001). CHS was significantly higher in the placebo group (13.75%) than in the Dex group (2.5%) (prevalence: [OR]: 0.161, 95% CI: 0.024-0.626; p = 0.020; incidence: [HR]: 0.17, 95% CI: 0.06-0.52; p = 0.009). Dex significantly upregulated BDNF, decreased Nfl, and uniquely increased lysophosphatidylethanolamine.

CONCLUSIONS

A low prophylactic dose of Dex significantly reduced the incidence of CH and CHS up to 72 h after CAS.

FUNDING

This work was funded by National Natural Science Foundation of China (no. 82271288) and the Henan Provincial Science and Technology Research Project (nos. 242300421192 and JQRC2023004).

A metabolic profile of xenon and metabolite associations with 6-month mortality after out-of-hospital cardiac arrest: A post-hoc study of the randomised Xe-Hypotheca trial

PURPOSE

Out-of-hospital cardiac arrest (OHCA) carries a relatively poor prognosis and requires multimodal prognostication to guide clinical decisions. Identification of previously unrecognized metabolic routes associated with patient outcome may contribute to future biomarker discovery. In OHCA, inhaled xenon elicits neuro- and cardioprotection. However, the metabolic effects remain unknown.

MATERIALS AND METHODS

In this post-hoc study of the randomised, 2-group, single-blind, phase 2 Xe-Hypotheca trial, 110 OHCA survivors were randomised 1:1 to receive targeted temperature management (TTM) at 33°C with or without inhaled xenon during 24 h. Blood samples for nuclear magnetic resonance spectroscopy metabolic profiling were drawn upon admission, at 24 and 72 h.

RESULTS

At 24 h, increased lactate, adjusted hazard-ratio 2.25, 95% CI [1.53; 3.30], p<0.001, and decreased branched-chain amino acids (BCAA) leucine 0.64 [0.5; 0.82], p = 0.007, and valine 0.37 [0.22; 0.63], p = 0.003, associated with 6-month mortality. At 72 h, increased lactate 2.77 [1.76; 4.36], p<0.001, and alanine 2.43 [1.56; 3.78], p = 0.001, and decreased small HDL cholesterol ester content (S-HDL-CE) 0.36 [0.19; 0.68], p = 0.021, associated with mortality. No difference was observed between xenon and control groups.

CONCLUSIONS

In OHCA patients receiving TTM with or without xenon, high lactate and alanine and decreased BCAAs and S-HDL-CE associated with increased mortality. It remains to be established whether current observations on BCAAs, and possibly alanine and lactate, could reflect neural damage via their roles in the metabolism of the neurotransmitter glutamate. Xenon did not significantly alter the measured metabolic profile, a potentially beneficial attribute in the context of compromised ICU patients.

TRIAL REGISTRATION

Trial Registry number: ClinicalTrials.gov Identifier: NCT00879892.

Effects of S-ketamine added to patient-controlled analgesia on early postoperative pain and recovery in patients undergoing thoracoscopic lung surgery: A randomized double-blinded controlled trial

STUDY OBJECTIVE

To investigate whether the addition of S-ketamine to patient-controlled hydromorphone analgesia decreases postoperative moderate-to-severe pain and improves the quality of recovery (QoR) in patients undergoing thoracoscopic lung surgery.

DESIGN

Single-center prospective randomized double-blinded controlled trial.

SETTING

Tertiary university hospital.

PATIENTS

242 patients undergoing thoracoscopic lung surgery.

INTERVENTIONS

Patients were randomized to receive intravenous patient-controlled analgesia (IV-PCA) with hydromorphone alone or hydromorphone combined with S-ketamine (0.5 mg/kg/48 h, 1 mg/kg/48 h, or 2 mg/kg/48 h).

MEASUREMENTS

Primary outcome was proportion of patients with moderate-to-severe pain. (numerical rating scale [NRS] pain scores ≥4 when coughing) within 2 days after surgery. Postoperative QoR scores and other prespecified outcomes were also recorded.

MAIN RESULTS

Of 242 enrolled patients, 220 were included in the final analysis. The results demonstrated that the incidence of postoperative moderate-to-severe pain was significantly different between the hydromorphone group and combined S-ketamine group (absolute difference, 27.9%; 95% confidence interval [CI], 11.7% to 42.1%; P < 0.001). Patients who received S-ketamine had lower NRS pain scores at rest and when coughing on postoperative day 1 (POD1; median difference 1 and 1, P < 0.001) and postoperative day 2 (POD2; median difference 1 and 1, P < 0.001). The QoR-15 scores were higher in the combined S-ketamine group on POD1 (mean difference 6, P < 0.001) and POD2 (mean difference 6, P < 0.001) than in the hydromorphone group. A higher dose of S-ketamine was associated with deeper sedation. No differences were detected in the other safety outcomes.

CONCLUSIONS

Addition of S-ketamine to IV-PCA hydromorphone significantly reduced the incidence of postoperative moderate-to-severe pain and improved the QoR in patients undergoing thoracoscopic lung surgery.

TRIAL REGISTRATION

Chinese Clinical Trail Register (identifier: ChiCTR2200058890).

A single extraction 96-well method for LC-MS/MS quantification of urinary eicosanoids, steroids and drugs

Urinary eicosanoid concentrations reflect inflammatory processes in multiple diseases and have been used as biomarkers of disease as well as suggested for patient stratification in precision medicine. However, implementation of urinary eicosanoid profiling in large-scale analyses is restricted due to sample preparation limits. Here we demonstrate a single solid-phase extraction of 300 µL urine in 96-well-format for prostaglandins, thromboxanes, isoprostanes, cysteinyl-leukotriene E4 and the linoleic acid-derived dihydroxy-octadecenoic acids (9,10- and 12,13-DiHOME). A simultaneous screening protocol was also developed for cortisol/cortisone and 7 exogenous steroids as well as 3 cyclooxygenase inhibitors. Satisfactory performance for quantification of eicosanoids with an appropriate internal standard was demonstrated for intra-plate analyses (CV = 8.5-15.1%) as well as for inter-plate (n = 35) from multiple studies (CV = 22.1-34.9%). Storage stability was evaluated at - 20 °C, and polar tetranors evidenced a 50% decrease after 5 months, while the remaining eicosanoids evidenced no significant degradation. All eicosanoids were stable over 3.5-years in urine stored at - 80 °C. This method will facilitate the implementation of urinary eicosanoid quantification in large-scale screening.

Differential Effect of Global Signal Regression Between Awake and Anesthetized Conditions in Mice

Introduction: In resting-state functional magnetic resonance imaging (rs-fMRI) studies, global signal regression (GSR) is a controversial preprocessing strategy. It effectively eliminates global noise driven by motion and respiration but also can introduce artifacts and remove functionally relevant metabolic information. Most preclinical rs-fMRI studies are performed in anesthetized animals, and anesthesia will alter both metabolic and neuronal activity. Methods: In this study, we explored the effect of GSR on rs-fMRI data collected under anesthetized and awake state in mice (n = 12). We measured global signal amplitude, and also functional connectivity (FC), functional connectivity density (FCD) maps, and brain modularity, all commonly used data-driven analysis methods to quantify connectivity patterns. Results: We found that global signal amplitude was similar between the awake and anesthetized states. However, GSR had a different impact on connectivity networks and brain modularity changes between states. We demonstrated that GSR had a more prominent impact on the anesthetized state, with a greater decrease in functional connectivity and increased brain modularity. We classified mice using the change in amplitude of brain modularity coefficient (ΔQ) before and after GSR processing. The results revealed that, when compared with the largest ΔQ group, the smallest ΔQ group had increased FCD in the cortex region in both the awake and anesthetized states. This suggests differences in individual mice may affect how GSR differentially affects awake versus anesthetized functional connectivity. Discussion: This study suggests that, for rs-fMRI studies which compare different physiological states, researchers should use GSR processing with caution.

Effects of continuous intravenous infusion with propofol on intestinal metabolites in rats

Microbial metabolites play an important role in regulating intestinal homeostasis and immune responses. Propofol is a common anesthetic in clinic, but it is not clear whether it affects intestinal metabolites in rats. Tail vein puncture was performed after adaptive feeding for 1 month in eight 2-month-old rats and they were given continuous intravenous infusion of propofol for 3 h. The feces of rats were divided into different groups based on time periods, with before and after anesthesia with propofol on days 1, 3 and 7 labeled as groups P, A1, A3 and A7, respectively. The effect of continuous intravenous infusion with propofol on rat fecal metabolites was determined using the non-targeted metabolomics technique gas chromatography coupled with a time-of-flight mass spectrometer analysis. The types and contents of metabolites in rat feces were changed after continuous intravenous infusion with propofol, but the changes were not statistically significant. The contents of the metabolites 3-hydroxyphenylacetic acid and palmitic acid increased from day 3 to 7, and it was shown that the two metabolites were positively correlated at a statistically significant level. Linoleic acid decreased to its lowest level on day 3, and it returned to pre-anesthesia level on day 7. At the same time, linoleic acid metabolism was a metabolic pathway that was co-enriched 7 days after infusion with propofol. Spearman correlation analysis showed that there was significant correlation between some differential metabolites and differential microorganisms. It was observed that zymosterol 1, cytosin and elaidic acid were negatively correlated with Alloprevotella in the A3 vs. P group. In the A7 vs. P group, cortexolone 3 and coprostan-3-one were positively correlated with Faecalibacterium, whilst aconitic acid was negatively correlated with it. In conclusion, the present study revealed statistically insignificant effects of continuous intravenous propofol on the intestinal metabolites in rats.

Evaluating the effects of S-ketamine on postoperative delirium in elderly patients following total hip or knee arthroplasty under intraspinal anesthesia: a single-center randomized, double-blind, placebo-controlled, pragmatic study protocol

Introduction

Postoperative delirium (POD) is an acute, transient brain disorder associated with decreased postoperative quality of life, dementia, neurocognitive changes, and mortality. A small number of trials have explored the role of S-ketamine in the treatment of POD due to its neuroprotective effects. Surprisingly, these trials have failed to yield supportive results. However, heterogeneity in delirium assessment methodologies, sample sizes, and outcome settings as well as deficiencies in S-ketamine use methods make the evidence provided by these studies less persuasive. Given the severe impact of POD on the health of elderly patients and the potential for S-ketamine to prevent it, we believe that designing a large sample size, and rigorous randomized controlled trial for further evaluation is necessary.

Methods

This is a single-center, randomized, double-blind, placebo-controlled, pragmatic study. Subjects undergoing total hip or knee arthroplasty will be randomized in a 1:1 ratio to intervention (n = 186) and placebo (n = 186) groups. This trial aims to explore the potential role of S-ketamine in the prevention of POD. Its primary outcome is the incidence of POD within 3 postoperative days. Secondary outcomes include the number of POD episodes, the onset and duration of POD, the severity and subtype of POD, pain scores and opioid consumption, sleep quality, clinical outcomes, and safety outcomes.

Discussion

To our knowledge, this is the first pragmatic study that proposes to use S-ketamine to prevent POD. We reviewed a large body of literature to identify potential preoperative confounding variables that may bias associations between the intervention and primary outcome. We will use advanced statistical methods to correct potential confounding variables, improving the test's power and external validity of test results. Of note, the patient population included in this trial will undergo intraspinal anesthesia. Although large, multicenter, randomized controlled studies have found no considerable difference in the effects of regional and general anesthesia on POD, patients receiving intraspinal anesthesia have less exposure to at-risk drugs, such as sevoflurane, propofol, and benzodiazepines, than patients receiving general anesthesia. At-risk drugs have been shown to negatively interfere with the neuroprotective effects of S-ketamine, which may be the reason for the failure of a large number of previous studies. There is currently a lack of randomized controlled studies evaluating S-ketamine for POD prevention, and our trial helps to fill a gap in this area.Trial registration: http://www.chictr.org.cn, identifier ChiCTR2300075796.

Efficacy and safety of remimazolam tosilate versus propofol in patients undergoing day surgery: a prospective randomized controlled trial

BACKGROUND

Remimazolam tosilate (RT) is a novel short-acting GABA (A) receptor agonist that has a rapid recovery from procedural sedation and can be fully reversed by flumazenil. To date, there have been relatively few articles comparing RT and propofol for general anesthesia. This study aimed to assess the efficacy and safety of RT with or without flumazenil compared with propofol in general anesthesia for day surgery.

METHODS

115 patients scheduled for day surgery were randomized into three groups: RT (n = 39), RT + flumazenil (n = 38) and propofol (n = 38). The primary endpoints were anesthesia induction time and time until fully alert. Anesthesia success rate, bispectral index (BIS) values, injection pain, opioid and vasopressor dosages, postoperative recovery profiles and perioperative inflammatory and cognitive changes were assessed. Any adverse events were recorded.

RESULTS

Induction times were similar among the three groups (P = 0.437), but the median time until fully alert in patients treated with RT was longer than that of the propofol or RT + flumazenil groups (17.6 min vs. 12.3 min vs. 12.3 min, P < 0.001). The three groups had comparable postoperative recovery quality and inflammatory and cognitive state changes (P > 0.05). Smaller percentages of patients who received RT (26.3%) and RT + flumazenil (31.6%) developed hypotension during anesthesia maintenance compared with propofol (68.4%), and consequently less ephedrine (P < 0.001) and phenylephrine (P = 0.015) were needed in the RT group. Furthermore, serum triglyceride levels were lower (P < 0.001) and injection pain was much less frequent in the RT with or without flumazenil groups compared with the propofol group (5.3% vs. 0% vs. 18.4%).

CONCLUSION

RT permits rapid induction and comparable recovery profile compared with propofol in general anesthesia for day surgery, but has a prolonged recovery time without flumazenil. The safety profile of RT was superior to propofol in terms of hypotension and injection pain.

TRIAL REGISTRATION

The study was registered at Chinese Clinical Trial Registry http://www.chictr.org.cn/ (Registration date: 19/7/2021; Trial ID: ChiCTR2100048904).

Efficacy and safety of Ciprofol for procedural sedation and anesthesia in non-operating room settings

STUDY OBJECTIVE

Ciprofol, a novel intravenous anesthetic, provides rapid recovery in patients undergoing colonoscopy. We aimed to examine the efficacy and safety of ciprofol in comparison with propofol for sedation or anesthesia in non-operating room settings including endoscopic submucosal dissection, endoscopic retrograde cholangiopancreatography, and flexible bronchoscopy (FB).

DESIGN

Prospective, randomized, double-blind, parallel-group clinical trial.

SETTING

University-affiliated teaching hospital.

PATIENTS

We recruited 207 patients scheduled for an endoscopic procedure from October 2021 to December 2021.

INTERVENTIONS

Patients were randomized into three groups according to the dose during induction (n = 69 each): 1) ciprofol 6 mg/kg/h, 2) ciprofol 8 mg/kg/h, or 3) propofol 40 mg/kg/h. Ciprofol or propofol was administered throughout the procedure.

MEASUREMENTS

The primary outcome was the success rate of sedation or anesthesia for the procedures. Secondary outcomes included induction time, endoscope insertion time, recovery time, discharge time, incidence of drug-related adverse events (AEs), neurological and inflammatory outcomes.

MAIN RESULTS

The procedure success rates in the three groups were 100%. The induction time in the 6 (3.3 ± 1.0 min) and 8 mg/kg/h (2.9 ± 0.6 min) ciprofol groups was longer than that in the propofol group (2.5 ± 0.6 min) only in patients undergoing FB (p = 0.004). The time for patients to be fully alert and discharged from the post-anesthesia care unit was comparable across the three groups (p > 0.05). The incidence of drug-related AEs in the propofol and 6 and 8 mg/kg/h ciprofol groups was 84.1%, 76.8%, and 79.7%. No pain on injection was reported by ciprofol groups. Neurological outcomes and inflammatory responses were comparable among the three groups.

CONCLUSIONS

Ciprofol induced a level of sedation or anesthesia equivalent to that induced by propofol in non-operating room settings except for a prolonged induction time in patients undergoing FB. Ciprofol had a safety profile similar to that of propofol. No pain on injection was reported by ciprofol.

Plasma metabolic profiling implicates dysregulated lipid metabolism and glycolytic shift in hyperinflammatory ARDS

Using latent class analysis (LCA) of clinical and protein biomarkers, researchers have identified two phenotypes of the acute respiratory distress syndrome (ARDS) with divergent clinical trajectories and treatment responses. We investigated whether plasma metabolites differed among patients with LCA-derived hyperinflammatory and hypoinflammatory ARDS, and we tested the prognostic utility of adding metabolic clusters to LCA phenotypes. We analyzed data from 93 patients with ARDS and sepsis enrolled in a multicenter prospective cohort of critically ill patients, comparing 970 metabolites between the two LCA-derived phenotypes. In all, 188 metabolites were differentially abundant between the two LCA-derived phenotypes. After adjusting for age, sex, confounding medications, and comorbid liver and kidney disease, 82 metabolites remained significantly different. Patients with hyperinflammatory ARDS had reduced circulating lipids but high levels of pyruvate, lactate, and malate. Metabolic cluster and LCA-derived phenotypes were each significantly and independently associated with survival. Patients with hyperinflammatory ARDS may be experiencing a glycolytic shift leading to dysregulated lipid metabolism. Metabolic profiling offers prognostic information beyond what is captured by LCA phenotypes alone. Deeper biological profiling may identify key differences in pathogenesis among patients with ARDS and may lead to novel targeted therapies.

Circulating oxylipin and bile acid profiles of dexmedetomidine, propofol, sevoflurane, and S-ketamine: a randomised controlled trial using tandem mass spectrometry

Background

This exploratory study aimed to investigate whether dexmedetomidine, propofol, sevoflurane, and S-ketamine affect oxylipins and bile acids, which are functionally diverse molecules with possible connections to cellular bioenergetics, immune modulation, and organ protection.

Methods

In this randomised, open-label, controlled, parallel group, Phase IV clinical drug trial, healthy male subjects (n=160) received equipotent doses (EC50 for verbal command) of dexmedetomidine (1.5 ng ml-1; n=40), propofol (1.7 μg ml-1; n=40), sevoflurane (0.9% end-tidal; n=40), S-ketamine (0.75 μg ml-1; n=20), or placebo (n=20). Blood samples for tandem mass spectrometry were obtained at baseline, after study drug administration at 60 and 130 min from baseline; 40 metabolites were analysed.

Results

Statistically significant changes vs placebo were observed in 62.5%, 12.5%, 5.0%, and 2.5% of analytes in dexmedetomidine, propofol, sevoflurane, and S-ketamine groups, respectively. Data are presented as standard deviation score, 95% confidence interval, and P-value. Dexmedetomidine induced wide-ranging decreases in oxylipins and bile acids. Amongst others, 9,10-dihydroxyoctadecenoic acid (DiHOME) -1.19 (-1.6; -0.78), P<0.001 and 12,13-DiHOME -1.22 (-1.66; -0.77), P<0.001 were affected. Propofol elevated 9,10-DiHOME 2.29 (1.62; 2.96), P<0.001 and 12,13-DiHOME 2.13 (1.42; 2.84), P<0.001. Analytes were mostly unaffected by S-ketamine. Sevoflurane decreased tauroursodeoxycholic acid (TUDCA) -2.7 (-3.84; -1.55), P=0.015.

Conclusions

Dexmedetomidine-induced oxylipin alterations may be connected to pathways associated with organ protection. In contrast to dexmedetomidine, propofol emulsion elevated DiHOMEs, oxylipins associated with acute respiratory distress syndrome, and mitochondrial dysfunction in high concentrations. Further research is needed to establish the behaviour of DIHOMEs during prolonged propofol/dexmedetomidine infusions and to verify the sevoflurane-induced reduction in TUDCA, a suggested neuroprotective agent.

Clinical trial registration

NCT02624401.

An intravenous anesthetic drug-propofol, influences the biological characteristics of malignant tumors and reshapes the tumor microenvironment: A narrative literature review

Malignant tumors are the second leading cause of death worldwide. This is a public health concern that negatively impacts human health and poses a threat to the safety of life. Although there are several treatment approaches for malignant tumors, surgical resection remains the primary and direct treatment for malignant solid tumors. Anesthesia is an integral part of the operation process. Different anesthesia techniques and drugs have different effects on the operation and the postoperative prognosis. Propofol is an intravenous anesthetic that is commonly used in surgery. A substantial number of studies have shown that propofol participates in the pathophysiological process related to malignant tumors and affects the occurrence and development of malignant tumors, including anti-tumor effect, pro-tumor effect, and regulation of drug resistance. Propofol can also reshape the tumor microenvironment, including anti-angiogenesis, regulation of immunity, reduction of inflammation and remodeling of the extracellular matrix. Furthermore, most clinical studies have also indicated that propofol may contribute to a better postoperative outcome in some malignant tumor surgeries. Therefore, the author reviewed the chemical properties, pharmacokinetics, clinical application and limitations, mechanism of influencing the biological characteristics of malignant tumors and reshaping the tumor microenvironment, studies of propofol in animal tumor models and its relationship with postoperative prognosis of propofol in combination with the relevant literature in recent years, to lay a foundation for further study on the correlation between propofol and malignant tumor and provide theoretical guidance for the selection of anesthetics in malignant tumor surgery.

Effects of subanaesthetic S-ketamine on postoperative delirium and cognitive function in elderly patients undergoing non-cardiac thoracic surgery: a protocol for a randomised, double-blinded, placebo-controlled and positive-controlled, non-inferiority trial (SKED trial)

INTRODUCTION

Postoperative delirium (POD) is a common and distressing complication after thoracic surgery. S-ketamine has neuroprotective properties as a dissociative anaesthetic. Emerging literature has indicated that S-ketamine can reduce cognitive impairment in patients with depression. However, the role of S-ketamine in preventing POD remains unknown. Therefore, this study aims to evaluate the effect of intraoperative prophylactic S-ketamine compared with that of dexmedetomidine on the incidence of POD in elderly patients undergoing non-cardiac thoracic surgery.

METHODS AND ANALYSIS

This will be a randomised, double-blinded, placebo-controlled, positive-controlled, non-inferiority trial that enrolled patients aged 60-90 years undergoing thoracic surgery. The patients will be randomly allocated in a ratio of 1:1:1 to S-ketamine, dexmedetomidine or normal saline placebo groups using computer-generated randomisation with a block size of six. The primary outcome will be the incidence of POD within 4 days after surgery and this will be assessed using a 3-Minute Diagnostic Confusion Assessment Method two times per day. The severity and duration of POD, the incidence of emergence delirium, postoperative pain, quality of sleep, cognitive function, and the plasma concentrations of acetylcholine, brain-derived neurotrophic factor, tumour necrosis factor-α and incidence of adverse events will be evaluated as secondary outcomes.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Institutional Review Board of the Cancer Hospital and the Institute of Guangzhou Medical University (ZN202119). At the end of the trial, we commit to making a public disclosure available, regardless of the outcome. The public disclosure will include a publication in an appropriate journal and an oral presentation at academic meetings.

TRIAL REGISTRATION NUMBER

ChiCTR2100052750 (NCT05242692).

Functional Magnetic Resonance Imaging of Brain Function and Emergence Agitation of Patients with Dexmedetomidine-Assisted General Anesthesia under Comfortable Nursing Intervention

In order to explore the effects of dexmedetomidine (DEX) on functional magnetic resonance imaging (fMRI) and emergence agitation of patients who underwent general anesthesia surgery with sevoflurane under comfortable nursing intervention, 66 patients who received upper abdominal surgery were selected as research objects. According to nursing and anesthesia methods, the patients were randomly divided into control group (routine nursing and anesthesia), group A (routine nursing and DEX-assisted anesthesia), and group B (comfortable nursing and DEX-assisted anesthesia). The differences in the brain fMRI characteristics, hemodynamic indexes, anesthesia recovery indexes, and nursing satisfaction in the perioperative period were evaluated. The results showed that the regional homogeneity values were different in different brain regions, but there was no difference in the Z value of functional connectivity(P > 0.05). Compared with the control group, heart rate, mean arterial pressure, awakening time, extubation time, the Riker sedation-agitation scale (SAS) score, and anesthetic dosage were signally decreased in group A and group B, while the Ramsay scores, the postanesthesia care unit (PACU) stay, and anesthesia maintenance time in the two groups was obviously increased(P < 0.05). Compared with group A, the extubation time, the SAS score, PACU stay, and hospital stay were all remarkably reduced in group B, while the nursing satisfaction score was greatly increased(P < 0.05). To sum up, DEX was helpful to safely and effectively reduce the occurrence of emergence agitation in patients under general anesthesia surgery with sevoflurane. Besides, comfortable nursing intervention could further reduce the incidence of emergence agitation in patients with general anesthesia, shorten the length of hospital stay, and improve nursing satisfaction.

Bispectral Index Monitoring and Observer Rating Scale Correlate with Dreaming during Propofol Anesthesia for Gastrointestinal Endoscopies

Background and objectives: Dreaming is a commonly reported side effect of propofol anesthesia. Materials and Methods: We investigated the inci-dence and character of dreams in patients undergoing intravenous propofol anesthesia and cor-related it with an observer rating scale of facial expression on the seven-point scale from pain to smile. A total of 124 patients undergoing gastrointestinal endoscopy were recruited in the pro-spective observational study. Bispectral index (BIS), blood pressure (BP), and pulse were moni-tored. Upon emergence from anesthesia, the patient’s facial expression was rated numerically. Thereafter, patients were asked whether they had dreams and to rate their dreams as pleasant or unpleasant. The mean age of participants was 53; body mass index, 26.17; duration of procedure, 20 min; and average propofol dose, 265 mg. Results: Dreaming was reported by 43% of patients. Dreams were pleasant in all but one patient. There was a significant correlation of the observer’s rating of facial expression with dreaming (r = 0.260; p = 0.004). Dreamers had higher scores of observer rating of facial expression (1 (0–2) vs. 0.5 (0–1), p = 0.006). Conclusions: BIS values were lower in the dreamers vs. non-dreamers 2 min after the endoscopy started (48 (43–62) vs. 59 (45–71), p = 0.038). Both BIS and observer ratings correlate with dreaming in patients undergoing gastrointestinal endos-copy. Trial registration number: NCT04235894.

On no man's land: Subjective experiences during unresponsive and responsive sedative states induced by four different anesthetic agents

To understand how anesthetics with different molecular mechanisms affect consciousness, we explored subjective experiences recalled after responsive and unresponsive sedation induced with equisedative doses of dexmedetomidine, propofol, sevoflurane, and S-ketamine in healthy male participants (N = 140). The anesthetics were administered in experimental setting using target-controlled infusion or vapouriser for one hour. Interviews conducted after anesthetic administration revealed that 46.9% (n = 46) of arousable participants (n = 98) reported experiences, most frequently dreaming or memory incorporation of the setting. Participants receiving dexmedetomidine reported experiences most often while S-ketamine induced the most multimodal experiences. Responsiveness at the end of anesthetic administration did not affect the prevalence or content of reported experiences. These results demonstrate that subjective experiences during responsive and unresponsive sedation are common and anesthetic agents with different molecular mechanisms of action may have different effects on the prevalence and complexity of the experiences, albeit in the present sample the differences between drugs were minute.