Effect of epidural anesthesia on the optic nerve sheath diameter in patients with pre-eclampsia: a prospective observational study.

INTRODUCTION: Optic nerve sheath diameter (ONSD) reflects intracranial pressure and is increased in pre-eclampsia. Administrating a significant volume of epidural solution into the epidural space can potentially increase ONSD. We investigated the impact of epidural local anesthetic injection on ONSD in patients with pre-eclampsia. METHODS: Patients with pre-eclampsia (n=11) and normotensive pregnant women (n=11) received de novo epidural anesthesia for cesarean delivery. We administered 21 mL of an epidural solution containing 2% lidocaine and 50 µg fentanyl into the lumbar epidural space in incremental doses. ONSD was measured at baseline, 3, 10, and 20 min after completing the epidural injection, after delivery, and at the end of surgery. Primary outcome was the change in ONSD from baseline to 3 min after epidural injection in patients with pre-eclampsia and normotensive pregnant women. Serial changes in the ONSD were analyzed using a linear mixed model. RESULTS: At baseline and 3 min after epidural drug injection, ONSD was significantly larger in patients with pre-eclampsia than in normotensive mothers (5.7 vs 4.1 mm, p=0.001 and 5.4 vs 4.1 mm, p<0.001, respectively). However, there were no significant changes in ONSD at 3 min after injection from baseline in either group (p>0.999). Linear mixed model demonstrated that ONSD did not change after epidural anesthesia in either group (p=0.279 and p=0.347, respectively). CONCLUSIONS: Despite a higher baseline ONSD in pre-eclampsia, epidural anesthesia did not further increase ONSD. Our findings indicate that epidural anesthesia can be safely administered in patients with pre-eclampsia at risk of increased intracranial pressure, without other intracranial pathology. TRIAL REGISTRATION NUMBER: NCT04095832.

Risk factors for chloral hydrate sedation failure in pediatric patients: a retrospective analysis.

Background: This study aimed to investigate the risk factors for chloral hydrate sedation failure and complications in a tertiary children's hospital in South Korea. Methods: A retrospective analysis of pediatric procedural sedation with chloral hydrate between January 1, 2021, and March 30, 2022, was performed. The collected data included patient characteristics, sedation history, and procedure. Multivariable regression analysis was performed to identify the risk factors for procedural sedation failure and complications. Results: A total of 6691 procedural sedation were included in the analysis; sedation failure following chloral hydrate (50 mg/kg) occurred in 1457 patients (21.8%) and was associated with a higher rate of overall complications compared to those with successful sedation (17.5% [225 / 1457] vs. 6.2% [322 / 5234]; P < 0.001; odds ratio, 3.236). In the multivariable regression analysis, the following factors were associated with increased risk of sedation failure: general ward or intensive care unit inpatient (compared with outpatient); congenital syndrome; oxygen dependency; history of sedation failure or complications with chloral hydrate; procedure more than 60 min; and magnetic resonance imaging, radiotherapy, or procedures with painful or intense stimuli (all P values < 0.05). Factors contributing to the complications included general ward inpatient, congenital syndromes, congenital heart disease, preterm birth, oxygen dependency, history of complications with chloral hydrate, and current sedation failure with chloral hydrate (all P values < 0.05). Conclusions: To achieve successful sedation with chloral hydrate, the patient's sedation history, risk factors, and the type and duration of the procedure should be considered.

Effect of positive end expiratory pressure on non-hypoxic apnea time and atelectasis during induction of anesthesia in infant: A randomized controlled trial.

INTRODUCTION: This study aimed to assess the impact of positive-end-expiratory pressure (PEEP) on the non-hypoxic apnea time in infants during anesthesia induction with an inspired oxygen fraction of 0.8. METHODS: This age stratified randomized controlled trial included patients under 1 year of age. Preoxygenation was performed using an inspired oxygen fraction of 0.8 for 2 min. Inspired oxygen fraction of 0.8 was administered via a face mask with volume-controlled ventilation at a tidal volume of 6 mL.kg-1, with or without 7 cmH2O of PEEP. Tracheal intubation was performed after 3 min of ventilation; however, it was disconnected from the breathing circuit. Ventilation was resumed once the pulse oximetry readings reached 95%. The primary outcome was the non-hypoxic apnea time, defined as the time from the cessation of ventilation to achieving a pulse oximeter reading of 95%. The secondary outcome measures included the degree of atelectasis assessed by ultrasonography and the presence of gastric air insufflation. RESULTS: Eighty-four patients were included in the final analysis. In the positive end-expiratory pressure group, the atelectasis score decreased (17.0 vs. 31.5, p < .001; mean difference and 95% CI of 11.6, 7.5-15.6), while the non-hypoxic apnea time increased (80.1 s vs. 70.6 s, p = .005; mean difference and 95% CI of -9.4, -16.0 to -2.9), compared to the zero end-expiratory pressure group, among infants who are 6 months old or younger, not in those aged older than 6 months. DISCUSSION: The application of positive end-expiratory pressure reduced the incidence of atelectasis and extended the non-hypoxic apnea time in infants who are 6 months old or younger. However, it did not affect the incidence of atelectasis nor the non-hypoxic apnea time in patients aged older than 6 months.

Atmospheric particulate matter and hypoxaemia in Korean children receiving general anaesthesia: A retrospective analysis.

BACKGROUND: The association between the concentration of atmospheric particulate matter on the day of surgery and the occurrence of intra-operative hypoxaemia in children receiving general anaesthesia is unclear. OBJECTIVE: To investigate the association between the exposure to of particulate matter on the day of surgery and the occurrence of intra-operative hypoxaemia, defined as a pulse oximetry oxygen saturation of less than 90% for more than 1 min, in children. DESIGN: Retrospective study. SETTING: Single-centre. PARTICIPANTS: Children aged 18 years or younger who received general anaesthesia between January 2019 and October 2020. INTERVENTION: Information on daily levels of particulate matter with a diameter 10 µm or less and 2.5 µm or less measured within a neighbourhood corresponding to the area defined by the hospital's zip code was obtained from publicly available air-quality data. MAIN OUTCOME MEASURES: The primary outcome was intra-operative hypoxaemia, defined as a pulse oximetry oxygen saturation of less than 90% lasting for more than 1 min, manually verified by anaesthesiologists using vital sign registry data extracted at 2 s intervals. RESULTS: Of the patients finally analysed, 3.85% (489/13 175) experienced intra-operative hypoxaemia. Higher levels of particulate matter 10 µm or less in diameter (≥81 µg m-3, 472/12 900, 3.7%) were associated with an increased occurrence of intra-operative hypoxaemia compared with lower particulate matter concentrations [<81 µg m-3, 17/275, 6.2%; adjusted odds ratio, 1.71; 95% confidence interval (CI), 1.04 to 2.83; P = 0.035]. CONCLUSION: The level of particulate matter on the day of surgery pose a risk of intra-operative hypoxaemia in children receiving general anaesthesia. If the concentrations of particulate matter 10 µm or less in diameter on the day of surgery are high, children receiving general anaesthesia should be managed with increased caution.

Reversible Solar Heating and Radiative Cooling Devices via Mechanically Guided Assembly of 3D Macro/Microstructures.

Solar heating and radiative cooling are promising solutions for decreasing global energy consumption because these strategies use the Sun (≈5800 K) as a heating source and outer space (≈3 K) as a cooling source. Although high-performance thermal management can be achieved using these eco-friendly methods, they are limited by daily temperature fluctuations and seasonal changes because of single-mode actuation. Herein, reversible solar heating and radiative cooling devices formed via the mechanically guided assembly of 3D architectures are demonstrated. The fabricated devices exhibit the following properties: i) The devices reversibly change between solar heating and radiative cooling under uniaxial strain, called dual-mode actuation. ii) The 3D platforms in the devices can use rigid/soft materials for functional layers owing to the optimized designs. iii) The devices can be used for dual-mode thermal management on a macro/microscale. The devices use black paint-coated polyimide (PI) films as solar absorbers with multilayered films comprising thin layers of polydimethylsiloxane/silver/PI, achieving heating and cooling temperatures of 59.5 and -11.9 °C, respectively. Moreover, mode changes according to the angle of the 3D structures are demonstrated and the heating/cooling performance with skin, glass, steel, aluminum, copper, and PI substrates is investigated.

Effects of goal-directed analgesia using the analgesia nociception index in children undergoing surgery for moyamoya disease: A randomised controlled trial.

BACKGROUND: The potential benefits of Analgesia Nociception Index guided intra-operative analgesia on intra-operative opioid consumption remains to be demonstrated in paediatric anaesthesia. OBJECTIVES: This study aimed to explore the effects of Analgesia Nociception Index guided analgesia on sufentanil consumption during anaesthesia and postoperative pain scores in paediatric patients with moyamoya disease. DESIGN: A prospective randomised controlled study. SETTING: Seoul National University Children's Hospital, Seoul, Republic of Korea. PATIENTS: A total of 40 children scheduled for encephaloduroarteriosynangiosis. MAIN OUTCOME MEASURES: The primary outcome was total intra-operative sufentanil consumption, and the secondary outcomes included postoperative pain scores and incidence of opioid-related adverse events. RESULTS: The Analgesia Nociception Index group showed lower intra-operative sufentanil consumption (in µg kg-1 h-1) compared with the Standard group (0.30 ±â€Š0.12 and 0.39 ±â€Š0.17, respectively; mean difference, -0.09; 95% confidence interval, -0.19 to 0.00; P = 0.049). Postoperatively, compared with the Standard group, the Analgesia Nociception Index group reported lower median pain scores at 18 and 24 h and maximum pain within 24 h (1 [0 to 2] vs. 3 [2 to 5]; P = 0.004, 1 [0 to 2] vs. 3 [1 to 4]; P = 0.041, and 4 [3 to 5] vs. 5 [4 to 7]; P = 0.045, respectively), with fewer patients experiencing nausea (3 [15%] vs. 10 [50%], P = 0.043). CONCLUSION: The Analgesia Nociception Index guided analgesic protocol can reduce intra-operative sufentanil consumption and postoperative pain within 24 h with fewer nausea symptoms in paediatric patients with moyamoya disease who undergo encephaloduroarteriosynangiosis. TRIAL REGISTRATION NUMBER: NCT05672212 (registered at clinicaltrials, principal investigator: K.E.H., registration date: 2 January 2023).

Threshold of somatic mosaicism leading to brain dysfunction with focal epilepsy.

Somatic mosaicism in a fraction of brain cells causes neurodevelopmental disorders, including childhood intractable epilepsy. However, the threshold for somatic mosaicism leading to brain dysfunction is unknown. In this study, we induced various mosaic burdens in focal cortical dysplasia type II (FCD II) mice, featuring mTOR somatic mosaicism and spontaneous behavioral seizures. The mosaic burdens ranged from approximately 1,000 to 40,000 neurons expressing the mTOR mutant in the somatosensory (SSC) or medial prefrontal (PFC) cortex. Surprisingly, approximately 8,000 to 9,000 neurons expressing the MTOR mutant, which are extrapolated to constitute 0.08-0.09% of total cells or roughly 0.04% of variant allele frequency (VAF) in the mouse hemicortex, were sufficient to trigger epileptic seizures. The mutational burden was correlated with seizure frequency and onset, with a higher tendency for electrographic inter-ictal spikes and beta- and gamma-frequency oscillations in FCD II mice exceeding the threshold. Moreover, mutation-negative FCD II patients in deep sequencing of their bulky brain tissues revealed somatic mosaicism of the mTOR pathway genes as low as 0.07% in resected brain tissues through ultra-deep targeted sequencing (up to 20 million reads). Thus, our study suggests that extremely low levels of somatic mosaicism can contribute to brain dysfunction.

Regulation of T Lymphocyte Functions through Calcium Signaling Modulation by Nootkatone.

Recent advancements in understanding the intricate molecular mechanisms underlying immunological responses have underscored the critical involvement of ion channels in regulating calcium influx, particularly in inflammation. Nootkatone, a natural sesquiterpenoid found in Alpinia oxyphylla and various citrus species, has gained attention for its diverse pharmacological properties, including anti-inflammatory effects. This study aimed to elucidate the potential of nootkatone in modulating ion channels associated with calcium signaling, particularly CRAC, KV1.3, and KCa3.1 channels, which play pivotal roles in immune cell activation and proliferation. Using electrophysiological techniques, we demonstrated the inhibitory effects of nootkatone on CRAC, KV1.3, and KCa3.1 channels in HEK293T cells overexpressing respective channel proteins. Nootkatone exhibited dose-dependent inhibition of channel currents, with IC50 values determined for each channel. Nootkatone treatment did not significantly affect cell viability, indicating its potential safety for therapeutic applications. Furthermore, we observed that nootkatone treatment attenuated calcium influx through activated CRAC channels and showed anti-proliferative effects, suggesting its role in regulating inflammatory T cell activation. These findings highlight the potential of nootkatone as a natural compound for modulating calcium signaling pathways by targeting related key ion channels and it holds promise as a novel therapeutic agent for inflammatory disorders.

Determination of optimal positive end-expiratory pressure using electrical impedance tomography in infants under general anesthesia: Comparison between supine and prone positions.

AIMS: This study determined the optimal positive end-expiratory pressure levels in infants in supine and prone positions under general anesthesia using electrical impedance tomography (EIT). METHODS: This prospective observational single-centre study included infants scheduled for surgery in the prone position. An electrical impedance tomography sensor was applied after inducing general anesthesia. The optimal positive end-expiratory pressure in the supine position was determined in a decremental trial based on EIT and compliance. Subsequently, the patient's position was changed to prone. Electrical impedance tomography parameters, including global inhomogeneity index, regional ventilation delay, opening pressure, the centre of ventilation, and pendelluft volume, were continuously obtained up to 1 h after prone positioning. The optimal positive end-expiratory pressure in the prone position was similarly determined. RESULTS: Data from 30 infants were analyzed. The mean value of electrical impedance tomography-based optimal positive end-expiratory pressure in the prone position was significantly higher than that in the supine position [10.9 (1.6) cmH2O and 6.1 (0.9) cmH2O, respectively (p < .001)]. Significant differences were observed between electrical impedance tomography- and compliance-based optimal positive end-expiratory pressure. Peak and mean airway, plateau, and driving pressures increased 1 h after prone positioning compared with those in the supine position. In addition, the centre of ventilation for balance in ventilation between the ventral and dorsal regions improved. CONCLUSION: The prone position required higher positive end-expiratory pressure than the supine position in mechanically ventilated infants under general anesthesia. EIT is a promising tool to find the optimal positive end-expiratory pressure, which needs to be individualized.

A wirelessly programmable, skin-integrated thermo-haptic stimulator system for virtual reality.

Sensations of heat and touch produced by receptors in the skin are of essential importance for perceptions of the physical environment, with a particularly powerful role in interpersonal interactions. Advances in technologies for replicating these sensations in a programmable manner have the potential not only to enhance virtual/augmented reality environments but they also hold promise in medical applications for individuals with amputations or impaired sensory function. Engineering challenges are in achieving interfaces with precise spatial resolution, power-efficient operation, wide dynamic range, and fast temporal responses in both thermal and in physical modulation, with forms that can extend over large regions of the body. This paper introduces a wireless, skin-compatible interface for thermo-haptic modulation designed to address some of these challenges, with the ability to deliver programmable patterns of enhanced vibrational displacement and high-speed thermal stimulation. Experimental and computational investigations quantify the thermal and mechanical efficiency of a vertically stacked design layout in the thermo-haptic stimulators that also supports real-time, closed-loop control mechanisms. The platform is effective in conveying thermal and physical information through the skin, as demonstrated in the control of robotic prosthetics and in interactions with pressure/temperature-sensitive touch displays.

Relationship between preinduction electroencephalogram patterns and propofol sensitivity in adult patients.

PURPOSE: To determine the precise induction dose, an objective assessment of individual propofol sensitivity is necessary. This study aimed to investigate whether preinduction electroencephalogram (EEG) data are useful in determining the optimal propofol dose for the induction of general anesthesia in healthy adult patients. METHODS: Seventy healthy adult patients underwent total intravenous anesthesia (TIVA), and the effect-site target concentration of propofol was observed to measure each individual's propofol requirements for loss of responsiveness. We analyzed preinduction EEG data to assess its relationship with propofol requirements and conducted multiple regression analyses considering various patient-related factors. RESULTS: Patients with higher relative delta power (ρ = 0.47, p < 0.01) and higher absolute delta power (ρ = 0.34, p = 0.01) required a greater amount of propofol for anesthesia induction. In contrast, patients with higher relative beta power (ρ = -0.33, p < 0.01) required less propofol to achieve unresponsiveness. Multiple regression analysis revealed an independent association between relative delta power and propofol requirements. CONCLUSION: Preinduction EEG, particularly relative delta power, is associated with propofol requirements during the induction of general anesthesia. The utilization of preinduction EEG data may improve the precision of induction dose selection for individuals.

The Effect of Postoperative Single-Injection Adductor Canal Block in Total Knee Arthroplasty Under Spinal Anesthesia With Intraoperative Dexmedetomidine Infusion.

Background: Single-injection adductor canal block (SACB) is one of the multimodal pain managements in total knee arthroplasty. The effect of an intrathecal local anesthetic is prolonged with an intraoperative dexmedetomidine infusion. Currently, SACB's effect along with the prolonged spinal anesthesia effect by dexmedetomidine has not been studied elsewhere. Methods: Seventy-eight patients were randomized to either the SACB group (n = 39) or the control group (n = 39). Spinal anesthesia and continuous infusion of dexmedetomidine were performed intraoperatively. The SACB was performed using 15 mL of either 0.5% ropivacaine or normal saline in postanesthesia care unit postoperatively. Primary endpoint examined the average numerical rating scale (NRS) pain scores at 2, 6, 12, and 24 hours after SACB while resting or moving. The secondary outcomes were the morphine equivalent, postoperative nausea and vomiting score, quadriceps strength, and overall satisfaction score. Results: The SACB group showed a lower average NRS pain score until 24 hours than the control group (2.4 vs 3.3 resting, 3.4 vs 4.1 moving). Resting and moving NRS scores at 6 and 12 hours were significantly lower in the SACB group, whereas no difference was found at 2, 24, and 48 hours, regardless of movement. The satisfaction score was higher in the SACB group than in the control group (9 [7.3-10.0] vs 7 [5.3-8.8]), and morphine equivalent at 2 hours was lower in the SACB group (2 [1-3]) than in the control group (2.9 [1.6-4]). Conclusions: SACB provided an additional analgesic effect in patients undergoing total knee arthroplasty under spinal anesthesia with continuous dexmedetomidine intravenous infusion.

Effect of converting from propofol to remimazolam with flumazenil reversal on recovery from anesthesia in outpatients with mental disabilities: a randomized controlled trial.

BACKGROUND: General anesthesia is often necessary for dental treatment of outpatients with mental disabilities. Rapid recovery and effective management of postoperative nausea and vomiting (PONV) are critical for outpatients. This study aimed to investigate the effect of transitioning from propofol to remimazolam with flumazenil reversal administered toward the end of surgery during propofol-based total intravenous anesthesia (TIVA) on recovery. METHODS: Adults with mental disabilities scheduled to undergo dental treatment were randomly assigned to receive either propofol-based TIVA (Group P) or propofol-remimazolam-based TIVA with flumazenil reversal (Group PR). Propofol was replaced with remimazolam 1 h before the end of surgery in Group PR; moreover, 0.5 mg of flumazenil was administered after the neuromuscular blockade reversal agent. The primary outcome was the duration of stay in the post-anesthesia care unit (PACU). The secondary outcomes included time to eye-opening, time to extubation, occurrence of PONV, and quality of recovery. RESULTS: Fifty-four patients were included in this study. The duration of stay in the PACU in Group PR was significantly shorter than that in Group P (mean difference, 8.7 min; confidence interval [95% CI], 3.3-14.2; P = 0.002). Group PR exhibited a shorter time to eye opening (mean difference, 5.4 min; 95% CI, 3.3-8.1; P < 0.001) and time to extubation (mean difference, 5.5 min; 95% CI, 3.6-7.9; P < 0.001) than Group P. Neither group required the administration of rescue analgesics, and the incidence of PONV was not reported. CONCLUSIONS: Transitioning from propofol to remimazolam 1 h before the end of surgery followed by flumazenil reversal reduced the duration of stay in the PACU and the time to eye opening and extubation without affecting the incidence of PONV and quality of recovery. TRIAL REGISTRATION NUMBER: Clinical Research Information Service (KCT0007794), Clinical trial first registration date: 12/10/2022.

Functional bio-inspired hybrid fliers with separated ring and leading edge vortices.

Recent advances in passive flying systems inspired by wind-dispersed seeds contribute to increasing interest in their use for remote sensing applications across large spatial domains in the Lagrangian frame of reference. These concepts create possibilities for developing and studying structures with performance characteristics and operating mechanisms that lie beyond those found in nature. Here, we demonstrate a hybrid flier system, fabricated through a process of controlled buckling, to yield unusual geometries optimized for flight. Specifically, these constructs simultaneously exploit distinct fluid phenomena, including separated vortex rings from features that resemble those of dandelion seeds and the leading-edge vortices derived from behaviors of maple seeds. Advanced experimental measurements and computational simulations of the aerodynamics and induced flow physics of these hybrid fliers establish a concise, scalable analytical framework for understanding their flight mechanisms. Demonstrations with functional payloads in various forms, including bioresorbable, colorimetric, gas-sensing, and light-emitting platforms, illustrate examples with diverse capabilities in sensing and tracking.

Effectiveness of head-mounted ultrasound display for radial arterial catheterisation in paediatric patients by anaesthesiology trainees: A randomised clinical trial.

BACKGROUND: The effectiveness of head mounted real-time ultrasound displays (hereafter referred to as 'smart glasses') in improving hand-eye coordination in less experienced individuals, such as trainees in anaesthesia, is unclear. OBJECTIVES: To compare the first-attempt success rate of smart glasses-assisted ultrasound-guided paediatric radial artery catheterisation with conventional ultrasound guided catheterisation performed by anaesthesiology trainees. DESIGN: Prospective randomised controlled trial. SETTINGS: Tertiary university hospital from September 2021 to February 2023. PATIENTS: One hundred and twenty-two paediatric patients (age <7 years, weight ≥3 kg) who required radial artery cannulation during general anaesthesia. INTERVENTIONS: The participants were randomly assigned to either the ultrasound screen group (control) or the smart glasses group prior to radial artery catheterisation. MAIN OUTCOME MEASURES: The primary outcome was the first attempt success rate. Secondary outcomes included the number of attempts, use of transfixion technique, overall complication rate, and clinical anaesthesiology (CA) year of the operators. RESULTS: A total of 119 paediatric patients were included in the analysis. The smart glasses group exhibited higher first-attempt success rate than did the control group (89.8% [53/59] vs. 71.7% [43/60]; P  = 0.023; odds ratio (OR) 3.49; (95% confidence interval (CI) 1.27-9.6). The overall number of attempts [median, 1; interquartile range (IQR), 1-1; range, 1-3 vs. median, 1; IQR, 1-2; range, 1-4; P   =  0.006], use of transfixion technique (12/59 [20.3%] vs. 28/60 [46.7%]; P  = 0.002), and overall complication rate (6.8% [4/59] vs. 30.0% [18/60]; P  = 0.002) were lower in the smart glasses group than in the control group. However, among paediatric anaesthesiology fellows (CA 5 years), the first- (89.3% [25/28] vs. 80.8% [21/26]; P  = 0.619) and second-attempt success rates (96.4% [27/28] vs. 80.8% [21/26]; P  = 0.163) did not differ between the two groups. CONCLUSIONS: Smart glasses-assisted ultrasound guided radial artery catheterisation improved the first attempt success rate among anaesthesiology trainees, reducing the number of attempts and overall complication rates in small paediatric patients. Smart glasses were more effective for anaesthesia residents (CA 2-4 years) but were not effective for paediatric anaesthesiology fellows (CA 5 years). TRIAL REGISTRATION: ClinicalTrials.gov (NCT05030649) ( https://classic.clinicaltrials.gov/ct2/show/NCT05030649 ).

Preoperative frailty assessment with ultrasound in elderly patients scheduled for total knee arthroplasty.

BACKGROUND: Frailty, a decline in physical and cognitive reserve capacity, renders patients susceptible to various stressors and has been linked to adverse outcomes and increased healthcare utilization. This study aimed to determine whether ultrasound measurements of the rectus abdominis (RA) and biceps brachii (BB) could predict frailty in patients scheduled for total knee arthroplasty. METHODS: Frailty was assessed using the Clinical Frailty Scale in adults aged ≥60 years. Ultrasound measurements of the rectus abdominis, BB, and quadriceps femoris muscles, along with thigh circumference measurements, were obtained before surgery. The predictive ability of the unadjusted and BMI- and body surface area (BSA)-adjusted measurements were evaluated using receiver operating characteristic curve analysis and area under the curve (AUC) values. Postoperative outcomes, such as admission to the intensive care unit or skilled nursing facility, delirium, falls, re-hospitalization, and 30-day mortality were recorded. RESULTS: We analyzed data from 148 patients. BB thickness provided a fair prediction of frailty. Average measurements of both BB adjusted for BMI (0.708, 95% CI 0.602-0.814; P<0.001), and BSA (0.708, 95% CI 0.598-0.817; P<0.001) had the highest AUC values. RA muscle measurements could not discriminate frailty. The BMI-adjusted measurements for: right quadriceps femoris thickness (AUC 0.614, 95% CI 0.503-0.725; P=0.044), left thigh circumference (AUC 0.648, 95% CI 0.528-0.769; P=0.016), and average thigh circumference (AUC 0.630, 95% CI 0.511-0.750; P=0.033) had statistically significant but poor AUC values. CONCLUSIONS: Preoperative ultrasound measurements of the bilateral BB can fairly predict frailty in patients scheduled for total knee arthroplasty.

Realism of Tactile Texture Playback: A Combination of Stretch and Vibration.

This study investigates the effects of two stimulation modalities (stretch and vibration) on natural touch sensation on the volar forearm. The skin-textile interaction was implemented by scanning three textures across the left forearm. The resulting skin displacements were recorded by the digital image correlation technique to capture the information imparted by the textures. The texture recordings were used to create three playback modes (stretch, vibration, and both), which were reproduced on the right forearm. Two psychophysical experiments compared the texture scans to rendered texture playbacks. The first experiment used a matching task and found that to maximize perceptual realism, i.e., similarity to a physical reference, subjects preferred the rendered texture to have a playback intensity of 1X-2X higher on DC components (stretch), and 1X-3.5X higher on AC components (vibration), varying across textures. The second experiment elicited similarity ratings between the texture scans and playbacks and showed that a combination of stretch and vibration was required to create differentiated texture sensations. However, the intensity amplification and use of two stimuli were still insufficient to create fully realistic texture sensations. We conclude that mechanisms beyond single-site uniaxial stimuli are needed to reproduce realistic textural sensations.

Comparison of remimazolam and dexmedetomidine for intraoperative sedation in patients undergoing lower extremity surgery under spinal anesthesia: a randomized clinical trial.

BACKGROUND: Dexmedetomidine sedation has advantages, such as low incidence of respiratory depression and prolonged block duration, but also significant disadvantages, such as slow onset, high rate of sedation failure, and a long context-sensitive half-life. Remimazolam provides rapid sedation and recovery, high sedation efficacy and has minimal hemodynamic effects. We hypothesized that patients who received remimazolam would require less rescue midazolam than dexmedetomidine. METHODS: Patients (n=103) scheduled for surgery under spinal anesthesia were randomized to receive dexmedetomidine (DEX group) or remimazolam (RMZ group) targeting a Modified Observer's Assessment of Alertness/Sedation score of 3 or 4. Rescue midazolam was administered if the patient failed to be sedated after the initial loading dose or despite infusion rate adjustment. RESULTS: Rescue midazolam administration was significantly higher in the DEX group (0% vs 39.2%; p<0.001). Patients in the RMZ group reached the target sedation level more rapidly. The incidences of bradycardia (0% vs 25.5%; p<0.001) and hypertension (0% vs 21.6%; p<0.001) were higher in the DEX group. Respiratory depression occurred at a higher rate in the RMZ group (21.2% vs 2.0%; p=0.002), but no patients required manual ventilation. Patients in the RMZ group recovered faster, had a shorter PACU stay and higher satisfaction scores. Hypotensive episodes in the PACU were more frequent in the DEX group (1.9% vs 29.4%; p<0.001). CONCLUSIONS: Remimazolam showed excellent sedation efficacy, minimal hemodynamic effects, and fewer adverse events in the PACU than dexmedetomidine. However, it is important to note that respiratory depression was more frequent with the use of remimazolam. TRIAL REGISTRATION NUMBER: NCT05447507.