Epidural dexmedetomidine or esketamine versus fentanyl to decrease ropivacaine use for labor analgesia: A randomized non-inferiority study.

Background: Epidural nonopioid adjuvants also reduce local anesthetic use. We aimed to test the hypothesis that, compared with the present standard fentanyl, the hourly consumption of local anesthetic was at least as good when dexmedetomidine or esketamine was combined with local anesthetic for patient-controlled epidural analgesia (PCEA). Methods: A total of 120 laboring nulliparous subjects requiring labor analgesia were recruited for the final statistical analysis. Subjects were randomized to receive 0.075 % ropivacaine added with one of three equivalent adjuvants: 0.4 µg/mL fentanyl, 0.4 µg/mL dexmedetomidine, or 1.0 mg/mL esketamine. The primary outcome was hourly ropivacaine consumption. Compared with the fentanyl group, a 20 % difference in hourly local anesthetic consumption between the dexmedetomidine and esketamine groups was considered a clinical difference (non-inferiority margin). Results: The hourly ropivacaine consumption of the fentanyl group was 12.4 (95 % confidence interval CI 11.2 to 13.6) ml/h, so the prespecified non-inferiority limit was 2.5 ml/h. The hourly ropivacaine consumption of the fentanyl group was not inferior to that of the dexmedetomidine group (12.4 ml/h vs. 11.9 ml/h, risk difference, 0.5; 95 % confidence interval CI, -1.0 to 2.0, meeting criteria for non-inferiority). However, the hourly ropivacaine consumption of the esketamine group was 14.3 ml/h, and that of the fentanyl group was 12.4 ml/h (risk difference, 1.9, 95 % CI, 0.2 to 3.6), failing to confirm non-inferiority with a non-inferiority margin of 20 %. The incidence of pruritus was highest in the fentanyl group, whereas the occurrence of mild dizziness was highest in the esketamine group. Conclusions: In setting of the conditions of this study, epidural dexmedetomidine was non-inferior compared with epidural fentanyl in combination with ropivacaine for PCEA during labor. Meanwhile, we failed to establish the non-inferiority of epidural esketamine compared with epidural fentanyl in combination with ropivacaine for labor analgesia.

Parallel Aluminum-Cobalt Oxide Nanosheet Arrays with High-Temperature Ferromagnetism.

Parallel nanomaterials possess unique properties and show potential applications in industry. Whereas, vertically aligned 2D nanomaterials have plane orientations that are generally chaotic. Simultaneous control of their growth direction and spatial orientation for parallel nanosheets remains a big challenge. Here, a facile preparation of vertically aligned parallel nanosheet arrays of aluminum-cobalt oxide is reported via a collaborative dealloying and hydrothermal method. The parallel growth of nanosheets is attributed to the lattice-matching among the nanosheets, the buffer layer, and the substrate, which is verified by a careful transmission electron microscopy study. Furthermore, the aluminum-cobalt oxide nanosheets exhibit high-temperature ferromagnetism with a 919 K Curie temperature and a 5.22 emu g-1 saturation magnetization at 300 K, implying the potential applications in high-temperature ferromagnetic fields.

Effect of positive end-expiratory pressure on pulmonary compliance and pulmonary complications in patients undergoing robot-assisted laparoscopic radical prostatectomy: a randomized control trial.

BACKGROUND: To observe the effects of different positive end-expiratory pressure (PEEP) ventilation strategies on pulmonary compliance and complications in patients undergoing robotic-assisted laparoscopic prostate surgery. METHODS: A total of 120 patients with the American Society of Anesthesiologists Physical Status Class I or II who underwent elective robotic-assisted laparoscopic prostatectomy were enrolled. We randomized the patients divided into divided into three groups of 40 patients each: PEEP0, PEEP5, or PEEP10. Master Anesthetist used volume control ventilation intraoperatively with an intraoperative deep muscle relaxation strategy. Respiratory mechanics indexes were recorded at six time-points: 10 mimuts after anaesthesia induction, immediately after pneumoperitoneum establishment, 30 min, 60 min, 90 min, and at the end of pneumoperitoneum. Arterial blood gas analysis and oxygenation index calculation were performed 10 mimuts after anaesthesia induction, 60 mimuts after pneumoperitoneum, and after tracheal extubation. Postoperative pulmonary complications were also recorded. RESULTS: After pneumoperitoneum, peak inspiratory pressure (Ppeak), plateau pressure (Pplat), mean pressure (Pmean), driving pressure (ΔP), and airway resistance (Raw) increased significantly, and pulmonary compliance (Crs) decreased, persisting during pneumoperitoneum in all groups. Between immediately after pneumoperitoneum establishment, 30 min, 60 min, and 90 min, pulmonary compliance in the 10cmH2OPEEP group was higher than in the 5cmH2OPEEP (P < 0.05) and 0cmH2OPEEP groups(P < 0.05). The driving pressure (ΔP) immediately after pneumoperitoneum establishment, at 30 min, 60 min, and 90 min in the 10cmH2OPEEP group was lower than in the 5cmH2OPEEP (P < 0.05) and 0cmH2OPEEP groups (P < 0.05). Sixty min after pneumoperitoneum and tracheal extubation, the PaCO2 did not differ significantly among the three groups (P > 0.05). The oxygenation index (PaO2/FiO2) was higher in the PEEP5 group than in the PEEP0 and PEEP10 groups 60 min after pneumoperitoneum and after tracheal extubation, with a statistically significant difference (P < 0.05). In postoperative pulmonary complications, the incidence of atelectasis was higher in the PEEP0 group than in the PEEP5 and PEEP10 groups, with a statistically significant difference (p < 0.05). CONCLUSION: The use of PEEP at 5cmH2O during RARP increases lung compliance, improves intraoperative oxygenation index and reduces postoperative atelectasis. TRIAL REGISTRATION: This study was registered in the China Clinical Trials Registry on May 30, 2020 (Registration No. ChiCTR2000033380).

Determination of the Dose-Response Relationship of Epidural Dexmedetomidine Combined with Ropivacaine for Labor Analgesia.

Background: The safety and efficacy of dexmedetomidine for epidural labor analgesia have been reported in numerous literatures, but the optimal dose has not been fully determined. The objective of this study was to determine the dose-response relationship of epidural dexmedetomidine (combined with ropivacaine) for labor analgesia. Methods: A total of 120 full-term laboring parturients requesting epidural labor analgesia were enrolled in the study from July 5, 2020 to September 22, 2021. The parturients were randomly assigned to receive 0, 0.1, 0.2, 0.3, 0.4 or 0.5 µg/mL dexmedetomidine combined with 0.075% ropivacaine epidurally. An effective dose was defined as numerical rating scale (NRS) pain score ≤3 at 30-minutes of epidural drug injection. The dose-response relationship of dexmedetomidine (with ropivacaine) for epidural labor analgesia was performed using probit regression. The median effective dose (ED50) and the 95% effective dose (ED95) values for epidural dexmedetomidine combined with 0.075% ropivacaine with 95% confidence intervals (CIs) were derived by interpolation. Results: The estimated values of ED50 and ED95 with 95% CIs for epidural dexmedetomidine (combined with 0.075% ropivacaine) were 0.085 (0.015 to 0.133) µg/mL and 0.357 (0.287 to 0.493) µg/mL, respectively. No differences were found among groups for sensory block level, number of parturients with Bromage score >0, total dosage of analgesics, cesarean delivery rate, fetal birth weight, Apgar score at 1-minute, Apgar score at 5-minutes and adverse effects. Compared with other groups, group dexmedetomidine 0.5 µg/mL had a longer duration of the first stage of labor. Conclusion: The ED50 and ED95 values of dexmedetomidine for epidural labor analgesia was 0.085 and 0.357 µg/mL under the conditions of this study. Dexmedetomidine is a suitable adjuvant for epidural labor analgesia.

Identification of the risk factors in perioperative respiratory adverse events in children under general anesthesia and the development of a predictive model.

BACKGROUND: This study explored the risk factors of perioperative respiratory adverse events in children under 12 years old undergoing general anesthesia surgery. A prediction model was constructed according to the related risk factors to provide a basis for timely clinical intervention and decision-making. METHODS: Children under 12 years old who underwent general anesthesia in our hospital between January 2016 and December 2020 were included in this study. The clinical data, including age, gender, weight, American Society of Anesthesiologists (ASA) grade classification, operation season, preoperative hospital stay, anesthesia time, and postoperative pain score, were collated. Continuous variables were converted to categorical variables. Logistic regression analysis was used to screen independent risk factors and a nomogram was constructed to predict the probability of adverse events. Fitting curves and receiver operating characteristic (ROC) curves were utilized to verify the model. RESULTS: Logistic regression analyses demonstrated that age [odds ratio (OR) =1.32, 95% confidence interval (CI): 1.08 to 1.49], body weight (OR =1.49, 95% CI: 1.21 to 1.84), anesthesia time (OR =1.61, 95% CI: 1.32 to 1.78), and surgery season (OR =1.12, 95% CI: 1.07 to 1.39) were independent risk factors for respiratory adverse events in children undergoing general anesthesia (P<0.05). The risk of respiratory-related adverse events increased in children with grade II ASA classification compared to children with grade I ASA classification (P<0.05). Similarly, the risk of respiratory adverse events increased in children with level III pain scores compared to children with level I pain scores (P<0.05). The calibration curve showed that the predicted curve was consistent with the actual curve. The area under the ROC curve (AUC) was 0.707, indicating that model showed great predictive ability. CONCLUSIONS: Age, weight, anesthesia time, operation season, ASA grade, and pain score were identified as independent risk factors for respiratory adverse events in children undergoing general anesthesia. Using the above risk factors, a nomogram was established to predict the risk of respiratory system-related adverse events. The predicted results were highly consistent with the actual risk, and the false positive rate was within a reasonable range.

Dexmedetomidine alleviates insulin resistance in hepatocytes by reducing endoplasmic reticulum stress.

PURPOSE: Dexmedetomidine (DEX) stabilizes intraoperative blood glucose levels and reduces insulin resistance (IR), a common perioperative complication. However, the molecular mechanisms underlying these effects remain unclear. Since endoplasmic reticulum stress (ERS) is a mechanism of IR, this study sought to examine whether DEX can effectively alleviate IR by reducing ERS. METHODS: HepG2 and LO2 cells were treated with different concentrations of insulin. The glucose content assay and Cell Counting Kit-8 (CCK-8) were then employed to determine the optimal insulin concentration capable of inducing IR without affecting cell viability. Insulin-resistant hepatocytes were cultured with different concentrations of DEX for 24 h, and the glucose concentration in the supernatant was measured. ERS was assessed by qPCR and western blotting. The latter was also used to quantify the expression of phosphorylated protein kinase B (p-AKT), phosphoenolpyruvate carboxykinase (PEPCK), and glucose 6 phosphatase (G6Pase), which are key proteins involved in the action of insulin. RESULTS: After 48-h of culturing with 10 µg/mL insulin, glucose consumption in hepatocytes was found to be reduced. IR hepatocytes cultured with 10, 100, or 1000 ng/ml DEX for 24 h showed a concentration-dependent increase in glucose consumption. Elevated mRNA and protein levels of ERS markers binding immunoglobulin protein (BIP) and ER protein 29 (ERp29), were reversed by DEX treatment. Moreover, reduced p-AKT and increased PEPCK and G6Pase protein levels in IR hepatocytes were also restored following DEX treatment. CONCLUSION: DEX may alleviate IR in hepatocytes by reducing ERS serving to restore insulin action via the IRS-1/PI3K/AKT pathway.

Breeding and preliminarily phenotyping of a congenic mouse model with alopecia areata.

In the current study, the alopecia areata gene was introduced into the C57BL/6 (B6) mouse through repeated backcrossing/intercrossing, and the allelic homozygosity of congenic AA(tj)mice (named B6.KM-AA) was verified using microsatellites. The gross appearance, growth characteristics, pathological changes in skin, and major organs of B6.KM-AA mice were observed. Counts and proportions of CD4⁺ and CD8⁺ T lymphocytes in peripheral blood were determined by flow cytometry. Results show that congenic B6.KM-AA mice were obtained after 10 generations of backcrossing/intercrossing. B6.KM-AA mice grew slower than B6 control mice and AA skin lesions were developed by four weeks of age. The number of hair follicles was reduced, but hair structures were normal. Loss of hair during disease progression was associated with CD4⁺ and CD8⁺ T lymphocytes infiltration peri-and intra-hair follicles. No pathological changes were found in other organs except for the skin. In the peripheral blood of B6.KM-AA mice, the percentage of CD4⁺ T cells was lower and percentage of CD8⁺ T cells higher than in control mice. These findings indicate that B6.KM-AA mice are characterized by a dysfunctional immune system, retarded development and T-cell infiltration mediated hair loss, making them a promising new animal model for human alopecia areata.