ABSTRACT
Importance: The chronic neuronal burden of traumatic brain injury (TBI) is not fully characterized by routine imaging, limiting understanding of the role of neuronal substrates in adverse outcomes. Objective: To determine whether tissues that appear healthy on routine imaging can be investigated for selective neuronal loss using [11C]flumazenil (FMZ) positron emission tomography (PET) and to examine whether this neuronal loss is associated with long-term outcomes. Design, Setting, and Participants: In this cross-sectional study, data were collected prospectively from 2 centers (University of Cambridge in the UK and Weill Cornell Medicine in the US) between September 1, 2004, and May 31, 2021. Patients with TBI (>6 months postinjury) were compared with healthy control participants (all aged >18 years). Individuals with neurological disease, benzodiazepine use, or contraindication to magnetic resonance imaging were excluded. Data were retrospectively collated with nonconsecutive recruitment, owing to convenience and scanner or PET ligand availability. Data were analyzed between February 1 and September 30, 2023. Exposure: Flumazenil voxelwise binding potential relative to nondisplaceable binding potential (BPND). Main Outcomes and Measures: Selective neuronal loss identified with FMZ PET was compared between groups on voxelwise and regional scales, and its association with functional, cognitive, and psychological outcomes was examined using Glasgow Outcome Scale (GOS) scores, measures of sustained executive attention (animal and sustained fluency), and 36-Item Short Form Health Survey (SF-36) scores. Diffusion tensor imaging was used to assess structural connectivity of regions of cortical damage, and its association with thalamic selective neuronal loss. Results: In this study, 24 patients with chronic TBI (mean [SD] age, 39.2 [12.3] years; 18 men [75.0%]) and 33 healthy control participants (mean [SD] age, 47.6 [20.5] years; 23 men [69.7%]) underwent FMZ PET. Patients with TBI had a median time of 29 (range, 7-95) months from injury to scan. They displayed selective neuronal loss in thalamic nuclei, over and above gross volume loss in the left thalamus, and bilateral central, mediodorsal, ventral-lateral dorsal, anterior, and ventral anterior thalamic nuclei, across a wide range of injury severities. Neuronal loss was associated with worse functional outcome using GOS scores (left thalamus, left ventral anterior, and bilateral central, mediodorsal, and anterior nuclei), worse cognitive outcome on measures of sustained executive attention (left thalamus, bilateral central, and right mediodorsal nuclei), and worse emotional outcome using SF-36 scores (right central thalamic nucleus). Chronic thalamic neuronal loss partially mirrored the location of primary cortical contusions, which may indicate secondary injury mechanisms of transneuronal degeneration. Conclusions and Relevance: The findings of this study suggest that selective thalamic vulnerability may have chronic neuronal consequences with relevance to long-term outcome, suggesting the evolving and potentially lifelong thalamic neuronal consequences of TBI. FMZ PET is a more sensitive marker of the burden of neuronal injury than routine imaging; therefore, it could inform outcome prognostication and may lead to the development of individualized precision medicine approaches.
Subject(s)
Brain Injuries, Traumatic , Positron-Emission Tomography , Thalamus , Humans , Male , Female , Adult , Brain Injuries, Traumatic/diagnostic imaging , Brain Injuries, Traumatic/pathology , Brain Injuries, Traumatic/complications , Cross-Sectional Studies , Middle Aged , Positron-Emission Tomography/methods , Thalamus/diagnostic imaging , Thalamus/pathology , Flumazenil/analogs & derivatives , Neurons/pathologyABSTRACT
The decontamination process for plumage-contaminated wild birds, such as those affected by oil spills, is lengthy and involves manual restraint and manipulation of all body parts. Birds commonly react to this in ways that suggest they are extremely stressed (eg, struggling, vocalizing). We proposed to reduce stress during the wash process using sedation and hypothesized that the use of sedation would not negatively impact survival. Contaminated birds in need of washing were randomly selected to be either sedated (butorphanol 2 mg/kg IM + midazolam 1 mg/kg IM and flumazenil 0.1 mg/kg IM for reversal) or not sedated at 3 US rehabilitation centers over the course of 1 year. Response to sedation was rated on a scale of 0-4 with 0 as no effect to 4 as excessively sedate. Data such as cloacal temperatures at various time points, lengths of various portions of the wash process, preening behavior in the drying pen, and disposition were collected. No statistical differences were found between sedated and nonsedated birds for any of the data points collected, including survival. There was a significant association between birds with higher cloacal temperatures in the drying pen and with birds held longer in the drying pen with improved survival; however, these findings were unrelated to whether the birds were sedated. Our findings show that sedation with butorphanol 2 mg/ kg IM and midazolam 1 mg/kg IM reversed with flumazenil 0.1 mg/kg IM can be used during the wash process for wild birds without adverse effects. Careful attention must be given to heat support for all birds while drying to prevent hypothermia.
Subject(s)
Birds , Butorphanol , Hypnotics and Sedatives , Midazolam , Restraint, Physical , Animals , Restraint, Physical/veterinary , Hypnotics and Sedatives/pharmacology , Hypnotics and Sedatives/administration & dosage , Butorphanol/administration & dosage , Butorphanol/pharmacology , Midazolam/pharmacology , Midazolam/administration & dosage , Decontamination/methods , Animals, Wild , Flumazenil/pharmacology , Flumazenil/administration & dosageABSTRACT
BACKGROUND: Flumazenil is a competitive benzodiazepine (BZD) antagonist most used for treating delirium in BZD overdoses. Since its introduction, many have expressed concerns about its safety secondary to the risk of inducing BZD withdrawal and refractory seizures. STUDY QUESTION: What is the incidence of adverse drug events after the administration of flumazenil in patients with suspected iatrogenic BZD delirium? STUDY DESIGN: This is a retrospective cross-sectional study of patients from a single center from 2010 to 2013. Patients experiencing delirium after receiving BZDs in the hospital were included if they had a bedside toxicology consult and were administered flumazenil. Patients were excluded if they were given BZDs for ethanol withdrawal or if they did not have mental status documentation before and after flumazenil administration. Descriptive statistics were calculated. MEASURES AND OUTCOMES: The primary outcome was the incidence of adverse drug events after flumazenil administration. The secondary outcome was the efficacy of flumazenil determined by the patient's mental status. RESULTS: A total of 501 patient records were reviewed, and 206 patients were included in the final analysis. Of those patients, 172 (83.5%) experienced an objective improvement in their mental status within 1 hour after flumazenil administration. A total of 5 patients experienced adverse events (2.4%), 95% confidence interval (0.78, 5.54). Of these, 3 patients experienced minor agitation or restlessness without pharmacologic intervention. Two patients experienced moderate agitation or restlessness that resolved with haloperidol or physostigmine administration. No patients had a reported seizure, 95% confidence interval (0.0, 1.77). CONCLUSIONS: Flumazenil seems to be a safe and effective intervention for the reversal of delirium secondary to iatrogenic BZD administration.
Subject(s)
Benzodiazepines , Delirium , Drug-Related Side Effects and Adverse Reactions , Flumazenil , Benzodiazepines/adverse effects , Benzodiazepines/antagonists & inhibitors , Delirium/drug therapy , Delirium/etiology , Retrospective Studies , Cross-Sectional Studies , Flumazenil/adverse effects , Flumazenil/therapeutic use , Humans , Male , Female , Adult , Middle Aged , Incidence , Drug-Related Side Effects and Adverse Reactions/epidemiology , Iatrogenic DiseaseABSTRACT
The optimal anesthetic agent for radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) and its impact on the recovery profiles remain uncertain. We compared the recovery and hemodynamic parameters between the remimazolam-flumazenil and propofol groups during RFCA. Patients were randomized into the remimazolam-flumazenil and propofol groups. The primary outcome measure was the time to eye opening following the discontinuation of anesthetic agents. Secondary outcomes included time to extubation, time to discharge from the operating room, intraprocedural hemodynamic variables and postoperative quality outcomes. Fifty-three patients were included in the final analysis (n = 26 in the remimazolam-flumazenil and n = 27 in the propofol group). The time to eye opening was significantly shorter in the remimazolam-flumazenil group compared to the propofol group (median [interquartile range]: 174 [157-216] vs. 353 [230-483] s, P < 0.001). The mean blood pressure and bispectral index were significantly higher in the remimazolam-flumazenil group compared to the propofol group (mean difference [95% CI], 7.2 [1.7-12.7] mmHg and 6 [3-8]; P = 0.011 and < 0.001, respectively), which were within target ranges in both groups. Other secondary outcomes were comparable between the groups. Consequently, remimazolam emerges as a promising anesthetic agent, characterized by rapid recovery and stable hemodynamics, during RFCA of AF.Trial registration: NCT05397886.
Subject(s)
Anesthesia, General , Atrial Fibrillation , Catheter Ablation , Flumazenil , Propofol , Humans , Atrial Fibrillation/surgery , Atrial Fibrillation/drug therapy , Propofol/administration & dosage , Male , Female , Middle Aged , Catheter Ablation/methods , Flumazenil/administration & dosage , Anesthesia, General/methods , Aged , Anesthesia Recovery Period , Benzodiazepines/administration & dosage , Hemodynamics/drug effects , Anesthetics, Intravenous/administration & dosageABSTRACT
PURPOSE OF REVIEW: Remimazolam is a novel benzodiazepine anesthetic/sedative, designed as a rapidly metabolized carboxylic acid. Since its recent launch, the role of remimazolam in modern anesthesia and sedation practice is still evolving. This review aims to outline the clinical pharmacology and clinical utility of remimazolam to elucidate its potential advantages and limitations. RECENT FINDINGS: Remimazolam is "short-acting" but not ultra-short-acting compared with propofol based on context-sensitive decrement times. But compared to propofol, the availability of the benzodiazepine antagonist, flumazenil, is considered an advantage, particularly in certain emergency situations such as in patients with difficult airways. However, because flumazenil is shorter acting than remimazolam when remimazolam accumulates or is present in a high concentration, the reappearance of remimazolam sedation may occur after the initial reversal of anesthesia/sedation from flumazenil administration. Although it is beneficial that remimazolam causes less respiratory depression and hypotension than propofol, serious respiratory depression and hypotension can still occur. Remimazolam administration causes minimal or no pain on injection. Remimazolam is associated with less postoperative nausea and vomiting than inhaled anesthetics, but propofol is clearly superior in this regard. The anesthetic/sedative effects may be prolonged by severe hepatic impairment; remimazolam tolerance can occur in long-term benzodiazepine users. SUMMARY: Remimazolam may be beneficial to use in procedural sedation and general anesthesia for patients with difficult airways or hemodynamic instability. Further clinical studies with remimazolam are warranted to identify the potential benefits in other settings and patient populations.
Subject(s)
Benzodiazepines , Hypnotics and Sedatives , Humans , Benzodiazepines/adverse effects , Benzodiazepines/pharmacology , Hypnotics and Sedatives/adverse effects , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/pharmacology , Anesthesia/methods , Anesthesia/adverse effects , Flumazenil/pharmacology , Propofol/adverse effects , Propofol/administration & dosageABSTRACT
Purpose: Remimazolam tosilate is a novel ultrafast-acting benzodiazepine that has a rapid emergence even after continuous infusion when using flumazenil. So far, relatively few articles are still focusing on the quality of recovery after general anesthesia with remimazolam, especially in day surgery. This study aimed to compare the early postoperative quality of recovery of remimazolam tosilate with flumazenil and propofol in patients undergoing day surgery. Patients and Methods: 137 patients scheduled for day surgery were randomly divided into the remimazolam tosilate or propofol group. The primary endpoint was the incidence of overall recovery assessed with the early postoperative quality of recovery scale (PostopQRS) on postoperative day 1 (POD 1). The Richmond Agitation-Sedation Scale (RASS) scores in the post-anesthesia care unit (PACU), extubation time, postoperative recovery profiles, and perioperative data were documented. Any adverse events were recorded. Results: The incidence of overall recovery on POD1 was 47.7% in the remimazolam tosilate group and 65.1% in the propofol group (odds ratio, 0.52; 95% confidence interval (CI) 0.26 to 1.06; P = 0.072). In general, the overall recovery of the PostopQRS increased over time, and its interaction between time and group was significant (P = 0.003). Among the five dimensions of PostopQRS, there exist statistical differences between groups including emotional state and cognitive recovery. Upon arrival at the PACU, the remimazolam group was more sedated and took longer to recover to a RASS score similar to propofol. The frequency of application of vasoactive drugs during anesthesia was similar in both groups (P = 0.119). Despite rapid emergence with remimazolam after flumazenil reversal, re-sedation (10.8%) or somnolence (60%) in the PACU was observed, and the length of PACU stay in patients treated with remimazolam tosilate was longer than that of the propofol (35 min vs 30 min, P<0.001). Conclusion: General anesthesia with remimazolam tosilate in conjunction with flumazenil reversal permits rapid recovery of consciousness in day surgery, but there was a notable occurrence of re-sedation or somnolence observed in PACU.
Subject(s)
Benzodiazepines , Hypnotics and Sedatives , Propofol , Humans , Propofol/administration & dosage , Female , Male , Prospective Studies , Middle Aged , Benzodiazepines/administration & dosage , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/pharmacology , Adult , Ambulatory Surgical Procedures , Anesthesia Recovery Period , Aged , Flumazenil/administration & dosage , Flumazenil/pharmacology , Flumazenil/therapeutic useABSTRACT
Introduction: In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl3, F-EtOAc, F-MeOH) of Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) root examined by using a pentylenetetrazol-induced model (PTZ) on mice. Methods: HE and its fractions as well as AE, in concentrations of (100, 200 and 400 mg/kg), valproate (Val) (100 and 200 mg/kg), and saline (negative control) (10 mg/kg) were injected intraperitoneally (i.p.) 30 min before PTZ (80 mg/kg, i.p.). The time taken before the onset of myoclonic convulsions (MC), MC duration, time taken before the onset of generalized tonic-clonic seizures (GTCS), the duration of GTCS, and the percentage of GTCS and mortality protection recorded. The plant's anticonvulsant mechanisms were assessed using flumazenil (5 mg/kg, i.p.) before AE (100, 200, and 400 mg/kg, i.p.) injection. GraphPad Prism software was used to compare the differences between various treatment groups with one-way analysis of variance (ANOVA) followed by TukeyKrammer multiple comparison tests. Results: All the plant samples except F-EtOAc significantly delayed the onset and decreased the duration of PTZ-induced MCS and GTCS, and significantly reduced the GTCS and mortality rate. Pretreatment with flumazenil diminished the significant anticonvulsant effects of AE against PTZ-induced seizures. Conclusions: It can report that extract of P. daurica ssp. macrophylla might be a helpful guide for future studies in the treatment of epilepsy.(AU)
Introducción: Epilepsia es el término usado para un grupo de trastornos caracterizado por las convulsiones espontáneas recurrentes. Un estudio enfocado en los productos naturales de los recursos tradicionales ofrece ventajas significativas que se están utilizando de manera más amplia en modelos animales de epilepsia y candidatos a mayor desarrollo clínico y sus fracciones (F-CHCl3, F-EtOAc, F-MeOH) de Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) raíz examinada utilizando un modelo inducido por pentilentetrazol (PTZ) en ratones. Métodos: La maceración dinámica utilizada para extraer HE de la planta y técnica de cromatografía en columna de sílice utilizada para obtener F-CHCl3, F-EtOAc, así como fracciones de F-MeOH. La extracción de raíces secas se utilizó con agua destilada y se provocó AE. Las muestras de plantas (100, 200 y 400 mg/kg), valproato (Val) (100 y 200 mg/kg) y suero (control negativo) se inyectaron por vía intraperitoneal (ip) 30 min antes de PTZ (80 mg/kg, ip). El tiempo transcurrido antes del comienzo de convulsiones mioclónicas (MC), duración de las MC, tiempo transcurrido antes del comienzo de convulsiones tónico-clónicas generalizadas (GTCS), la duración de GTCS, así como el porcentaje de GTCS y protección contra la mortalidad registrada. Los mecanismos anticonvulsivos de planta fueron evaluados mediante el uso de flumazenil (5 mg/kg, ip) antes de AE (100, 200 y 400 mg/kg, ip) inyección. Se utilizaba el software GraphPad Prism® comparando las diferencias entre varios grupos de tratamiento con un análisis unilateral de variación (ANOVA) seguido por las pruebas de comparación múltiple de Tukey's Krammer. Resultados: Todas las muestras de plantas, excepto F-EtOAc, retrasaron de manera considerable el inicio, y disminuyeron la duración de PTZ inducidos por MCS y GTCS, y redujo significativamente el GTCS, así como la tasa de mortalidad...(AU)
Subject(s)
Animals , Anticonvulsants , Seizures , Epilepsy/drug therapy , Flumazenil/therapeutic use , Receptors, GABA , Paeonia , Neurology , Nervous System Diseases , Models, AnimalABSTRACT
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.
Subject(s)
Anesthesia Recovery Period , Anesthetics, Intravenous , Flumazenil , Propofol , Humans , Flumazenil/therapeutic use , Male , Female , Adult , Middle Aged , Benzodiazepines/administration & dosage , Postoperative Nausea and Vomiting , Length of Stay/statistics & numerical data , OutpatientsABSTRACT
INTRODUCTION: In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl3, F-EtOAc, F-MeOH) of Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) root examined by using a pentylenetetrazol-induced model (PTZ) on mice. METHODS: HE and its fractions as well as AE, in concentrations of (100, 200 and 400mg/kg), valproate (Val) (100 and 200mg/kg), and saline (negative control) (10mg/kg) were injected intraperitoneally (i.p.) 30min before PTZ (80mg/kg, i.p.). The time taken before the onset of myoclonic convulsions (MC), MC duration, time taken before the onset of generalized tonic-clonic seizures (GTCS), the duration of GTCS, and the percentage of GTCS and mortality protection recorded. The plant's anticonvulsant mechanisms were assessed using flumazenil (5mg/kg, i.p.) before AE (100, 200, and 400mg/kg, i.p.) injection. GraphPad Prism software was used to compare the differences between various treatment groups with one-way analysis of variance (ANOVA) followed by Tukey-Krammer multiple comparison tests. RESULTS: All the plant samples except F-EtOAc significantly delayed the onset and decreased the duration of PTZ-induced MCS and GTCS, and significantly reduced the GTCS and mortality rate. Pretreatment with flumazenil diminished the significant anticonvulsant effects of AE against PTZ-induced seizures. CONCLUSIONS: It can report that extract of P. daurica ssp. macrophylla might be a helpful guide for future studies in the treatment of epilepsy.
Subject(s)
Anticonvulsants , Paeonia , Animals , Mice , Anticonvulsants/pharmacology , Anticonvulsants/therapeutic use , Pentylenetetrazole/toxicity , Flumazenil , Seizures/chemically induced , Seizures/drug therapyABSTRACT
Dimdazenil (Junoenil®) is a small-molecule, oral, partial positive allosteric modulator of the gamma-aminobutyric acid (GABA)A receptor that is being developed by Zhejiang Jingxin Pharmaceutical in collaboration with Evotec for the treatment of insomnia. Dimdazenil is designed to overcome issues associated with full GABAA receptor agonists, such as tolerance, withdrawal symptoms and associated adverse effects. On 29 November 2023, dimdazenil oral capsules received approval in China for the short-term treatment of insomnia. This article summarizes the milestones in the development of dimdazenil leading to this first approval for insomnia.
Subject(s)
Drug Approval , Sleep Initiation and Maintenance Disorders , Humans , Sleep Initiation and Maintenance Disorders/drug therapy , China , GABA Modulators/pharmacology , GABA Modulators/therapeutic use , GABA Modulators/adverse effects , GABA Modulators/administration & dosage , Receptors, GABA-A/metabolism , Receptors, GABA-A/drug effects , Administration, Oral , Flumazenil/pharmacology , Flumazenil/therapeutic useABSTRACT
Purpose: To evaluate the effect of flumazenil antagonizing remimazolam on postoperative nausea and vomiting (PONV) after gynecologic day surgery. Patients and Methods: 141 cases of gynaecological daycase surgery patients in Weifang People's Hospital were selected, randomized into group F (flumazenil group, 71 cases) and group C (control group, 70 cases). Dexamethasone 5 mg, flurbiprofen axetil 50 mg, and droperidol 1 mg were given intravenously before induction of anesthesia in both groups. Anesthesia induction: Remimazolam 0.25mg / kg was injected within 1 minute. After the patient fell asleep, mivacurium chloride 0.2mg / kg was injected for 30 seconds and alfentanil 20ug / kg was injected for 30 seconds. Anesthesia maintenance: Remimazolam 1mg/kg/h and alfentanil 40ug/kg/h were continuously pumped by micro pump. Stopping the injection of remimazolam and alfentanil at the end of the operation. Flumazenil 0.2 mg was given to antagonize remimazolam in group F after 1 minute. Group C was given an equal volume of saline. The incidence of PONV in the postoperative PACU and over a 24-hour period, patient awakening time, and general patient information were recorded. Results: The incidence of PONV in both groups within 24 hours was 50.70% in group F was significantly higher than 32.86% in group C. The difference was statistically significant (P < 0.05). The incidence of PONV in the PACU was 5.6% in group F and 8.6% in group C. The difference was not statistically significant (p > 0.05). Conclusion: Flumazenil antagonism of remimazolam increases the incidence of PONV within 24 hours in gynecologic day surgery patients and has no significant effect on the incidence of PONV in the PACU.
Subject(s)
Flumazenil , Gynecologic Surgical Procedures , Postoperative Nausea and Vomiting , Female , Humans , Alfentanil , Ambulatory Surgical Procedures , Antiemetics/pharmacology , Benzodiazepines , Flumazenil/pharmacology , Gynecologic Surgical Procedures/adverse effects , Postoperative Nausea and Vomiting/drug therapyABSTRACT
PURPOSE: Type 2 diabetes mellitus (T2DM) is associated with a greater risk of Alzheimer's disease. Synaptic impairment and protein aggregates have been reported in the brains of T2DM models. Here, we assessed whether neurodegenerative changes in synaptic vesicle 2 A (SV2A), γ-aminobutyric acid type A (GABAA) receptor, amyloid-ß, tau and receptor for advanced glycosylation end product (RAGE) can be detected in vivo in T2DM rats. METHODS: Positron emission tomography (PET) using [18F]SDM-8 (SV2A), [18F]flumazenil (GABAA receptor), [18F]florbetapir (amyloid-ß), [18F]PM-PBB3 (tau), and [18F]FPS-ZM1 (RAGE) was carried out in 12-month-old diabetic Zucker diabetic fatty (ZDF) and SpragueDawley (SD) rats. Immunofluorescence staining, Thioflavin S staining, proteomic profiling and pathway analysis were performed on the brain tissues of ZDF and SD rats. RESULTS: Reduced cortical [18F]SDM-8 uptake and cortical and hippocampal [18F]flumazenil uptake were observed in 12-month-old ZDF rats compared to SD rats. The regional uptake of [18F]florbetapir and [18F]PM-PBB3 was comparable in the brains of 12-month-old ZDF and SD rats. Immunofluorescence staining revealed Thioflavin S-negative, phospho-tau-positive inclusions in the cortex and hypothalamus in the brains of ZDF rats and the absence of amyloid-beta deposits. The level of GABAA receptors was lower in the cortex of ZDF rats than SD rats. Proteomic analysis further demonstrated that, compared with SD rats, synaptic-related proteins and pathways were downregulated in the hippocampus of ZDF rats. CONCLUSION: These findings provide in vivo evidence for regional reductions in SV2A and GABAA receptor levels in the brains of aged T2DM ZDF rats.
Subject(s)
Aniline Compounds , Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Ethylene Glycols , Fluorine Radioisotopes , Pyridines , Pyrrolidines , Rats , Animals , Flumazenil/metabolism , Receptors, GABA-A/metabolism , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Experimental/metabolism , Synaptic Vesicles/metabolism , Proteomics , Rats, Zucker , Positron-Emission Tomography/methods , Brain/diagnostic imaging , Brain/metabolism , gamma-Aminobutyric Acid/metabolismABSTRACT
BACKGROUND: Remimazolam, a short acting benzodiazepine, is being used for general anaesthesia. The results of studies comparing recovery after propofol with that of remimazolam are inconsistent. Given that flumazenil reverses the sedative effects of remimazolam, we hypothesised that it would speed up recovery from remimazolam general anaesthesia. OBJECTIVES: The aim of this trial was to compare the speed of recovery from general anaesthesia between propofol and remimazolam reversed with flumazenil in patients undergoing minimally invasive breast surgery. DESIGN: Randomised, single-centre, double-blind controlled trial. SETTING: A tertiary teaching hospital in South Korea from August 2022 to December 2022. PATIENTS: Adult patients (≥19âyears of age) about to undergo general anaesthesia for scheduled breast cancer surgery. INTERVENTIONS: Patients were randomly allocated to either the propofol or the remimazolam/flumazenil group. The emergence process was monitored by only one anaesthesiologist. MAIN OUTCOME MEASURES: The primary outcome was the time to eye opening to command during recovery from the general anaesthesia. Time to removal of the supraglottic airway (SGA) time to discharge, and the Riker sedation agitation scale (SAS) score (1 to 4) during emergence were compared as secondary outcomes. RESULTS: The remimazolam group had a significantly shorter mean time to eye opening than the propofol group [127â±â51 vs. 314â±â140âs; mean difference 187âs (95% confidence interval (CI), 133 to 241âs; P â<â0.001]. The remimazolam group also had shorter times to SGA removal [169â±â51 vs. 366â±â149âs; mean difference 198âs (95% CI, 140 to 255âs); P â<â0.001] and time to discharge from the operating room [243â±â55 vs. 449â±â159âs; mean difference 206âs (95% CI, 145 to 267âs); P â<â0.001]. The SAS scores during emergence also differed significantly, with 1 patient in the propofol group and 25 in the remimazolam group attaining scores of 4 ( P â<â0.001). CONCLUSION: Administration of remimazolam with flumazenil may be a promising option for patients undergoing breast cancer surgery, providing faster recovery and better SAS scores than propofol during emergence from general anaesthesia. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05435911).
Subject(s)
Breast Neoplasms , Propofol , Adult , Humans , Female , Flumazenil , Anesthesia, Intravenous , Benzodiazepines , Anesthesia, General , Breast Neoplasms/surgeryABSTRACT
Hypotensive influences of benzodiazepines and other GABAA receptor ligands, recognized in clinical practice, seem to stem from the existence of "vascular" GABAA receptors in peripheral blood vessels, besides any mechanisms in the central and peripheral nervous systems. We aimed to further elucidate the vasodilatatory effects of ligands acting through GABAA receptors. Using immunohistochemistry, the rat aortic smooth muscle layer was found to express GABAA γ2 and α1-5 subunit proteins. To confirm the role of "vascular" GABAA receptors, we investigated the vascular effects of standard benzodiazepines, midazolam, and flumazenil, as well as the novel compound MP-III-058. Using two-electrode voltage clamp electrophysiology and radioligand binding assays, MP-III-058 was found to have modest binding but substantial functional selectivity for α5ß3γ2 over other αxß3γ2 GABAA receptors. Tissue bath assays revealed comparable vasodilatory effects of MP-III-058 and midazolam, both of which at 100 µmol/L concentrations had efficacy similar to prazosin. Flumazenil exhibited weak vasoactivity per se, but significantly prevented the relaxant effects of midazolam and MP-III-058. These studies indicate the existence of functional GABAA receptors in the rat aorta, where ligands exert vasodilatory effects by positive modulation of the benzodiazepine binding site, suggesting the potential for further quest for leads with optimized pharmacokinetic properties as prospective adjuvant vasodilators.
Subject(s)
Flumazenil , Midazolam , Animals , Rats , Midazolam/pharmacology , Flumazenil/pharmacology , Benzodiazepines/pharmacology , Aorta , Receptors, GABA-A , gamma-Aminobutyric AcidABSTRACT
BACKGROUND: This report describes the successful rescue of a 12-year-old girl who ingested large quantities of clonazepam tablets. METHODS: The patient was promptly treated with flumazenil and hemoperfusion to alleviate the symptoms of central depression. Therapeutic drug monitoring was used to evaluate detoxification efficacy. The authors analyzed the rescue protocol for clonazepam poisoning based on the pathophysiology, clinical manifestations, and pharmacokinetics of clonazepam overdose. RESULTS: The patient responded well to the treatment and was discharged from the hospital without adverse events. CONCLUSIONS: This case study demonstrated the effectiveness and safety of combining flumazenil with hemoperfusion as a treatment for clonazepam poisoning. This study aimed to provide insights into more effective methods for treating clonazepam overdose and contribute to the ongoing issue of managing this condition.
Subject(s)
Clonazepam , Flumazenil , Child , Female , Humans , Clonazepam/poisoning , Flumazenil/therapeutic useABSTRACT
BACKGROUND: General anaesthesia can immobile patients during interventional neuroradiology to improve image quality. Remimazolam, an ultrashort-acting benzodiazepine, is advantageous for haemodynamic stability. This study compared remimazolam and propofol anaesthesia during neuroradiology procedures regarding intraoperative hypotensive events and rapid recovery. METHODS: This single-masked randomised-controlled study included 76 participants who underwent elective endovascular embolisation in a single centre. Patients were randomised between a continuous remimazolam infusion (n = 38) or a target-controlled propofol infusion group (n = 38). In the remimazolam group, flumazenil (0.2 mg) was administered at the end of the procedure. Phenylephrine was titrated to maintain the mean arterial pressure within ± 20% of the baseline value. The primary outcome was the total phenylephrine dose during the procedure. RESULTS: The total phenylephrine dose was 0.0 [0.0-30.0] µg in the remimazolam group and 30.0 [0.0-205.0] µg in the propofol group (p = 0.001). Hypotensive events were observed in 11 (28.9%) patients in the remimazolam group and 23 (60.5%) patients in the propofol group (p = 0.001). Recovery times to spontaneous breathing, eye-opening, extubation, and orientation were shorter in the remimazolam group than in the propofol group (all p < 0.001). CONCLUSIONS: Remimazolam anaesthesia showed superior haemodynamic stability compared with propofol anaesthesia during neuroradiology procedures. Systematic use of flumazenil enabled rapid recovery from remimazolam anaesthesia. REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry; Registration number: UMIN000047384; URL: https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000054046.
Subject(s)
Propofol , Humans , Flumazenil/therapeutic use , Benzodiazepines , Anesthesia, General , Phenylephrine/therapeutic useABSTRACT
General anxiety disorders are among the most prevalent mental health problems worldwide. The emergence and development of anxiety disorders can be due to genetic (30-50%) or non-genetic (50-70%) factors. Despite medical progress, available pharmacotherapies are sometimes ineffective or can cause undesirable side effects. Thus, it becomes necessary to discover new safe and effective drugs against anxiety. This study evaluated the anxiolytic effect in adult zebrafish (Danio rerio) of a natural pyrroloformamide (PFD), N-(4,5-dihydro-5-oxo-1,2-dithiolo-[4,3,b]-pyrrole-6-yl)-N-methylformamide, isolated from a Streptomyces sp. bacterium strain recovered from the ascidian Eudistoma vannamei. The complete structure of PFD was determined by a detailed NMR analysis, including 1H-13C and 1H-15N-HBMC data. In addition, conformational and DFT computational studies also were performed. A group of fishes (n = 6) was treated orally with PFD (0.1, 0.5 and 1.0 mg/mL; 20 µL) and subjected to locomotor activity and light/dark tests, as well as, acute toxicity 96 h. The involvement of the GABAergic and serotonergic (5-HT) systems was investigated using flumazenil (a silent modulator of GABA receptor) and 5-HT1, 5-HT2A/2C and 5-HTR3A/3B receptors antagonists, known as pizotifen, granisetron and cyproheptadine, respectively. PFD was nontoxic, reduced locomotor activity and promoted the anxiolytic effect in zebrafish. Flumazenil did not inhibit the anxiolytic effect of the PFD via the GABAergic system. This effect was reduced by a pretreatment with pizotifen and granisetron, and was not reversed after treatment with cyproheptadine. Molecular docking and dynamics studies confirmed the interaction of PFD with the 5-HT receptor.Communicated by Ramaswamy H. Sarma.
Pyrroloformamide (PFD), isolated from the marine Streptomyces sp. associated ascidian Eudistoma vannamei, showed no toxicity in adult zebrafish but reduced its locomotor activity.The structural elucidation of PFD was determined by the analysis of 1D and 2D NMR and HRESIMS data.The density functional theory (DFT) study confirmed the existence of two conformers as determined by NMR spectra.The serotonergic system modulated the anxiolytic effect of PFD via the 5-HT receptor in adult zebrafish.Molecular docking and dynamics studies confirmed the interaction of PFD with the 5-HT receptor.
Subject(s)
Anti-Anxiety Agents , Animals , Anti-Anxiety Agents/pharmacology , Anti-Anxiety Agents/therapeutic use , Zebrafish , Serotonin , Flumazenil/pharmacology , Pizotyline , Molecular Docking Simulation , Granisetron , CyproheptadineABSTRACT
Among opioids, buprenorphine presents a favorable safety profile with a limited risk of respiratory depression. However, fatalities have been reported when buprenorphine is combined to a benzodiazepine. Potentiation of buprenorphine interaction with opioid receptors (ORs) with benzodiazepines, and/or vice versa, is hypothesized to explain this drug-drug interaction (DDI). The mutual DDI between buprenorphine and benzodiazepines was investigated at the neuroreceptor level in nonhuman primates (n = 4 individuals) using brain PET imaging and kinetic modelling. The binding potential (BPND) of benzodiazepine receptor (BzR) was assessed using 11C-flumazenil PET imaging before and after administration of buprenorphine (0.2 mg, i.v.). Moreover, the brain kinetics and receptor binding of buprenorphine were investigated in the same individuals using 11C-buprenorphine PET imaging before and after administration of diazepam (10 mg, i.v.). Outcome parameters were compared using a two-way ANOVA. Buprenorphine did not impact the plasma nor brain kinetics of 11C-flumazenil. 11C-flumazenil BPND was unchanged following buprenorphine exposure, in any brain region (p > 0.05). Similarly, diazepam did not impact the plasma or brain kinetics of 11C-buprenorphine. 11C-buprenorphine volume of distribution (VT) was unchanged following diazepam exposure, in any brain region (p > 0.05). To conclude, our PET imaging findings do not support a neuropharmacokinetic or neuroreceptor-related mechanism of the buprenorphine/benzodiazepine interaction.
Subject(s)
Benzodiazepines , Buprenorphine , Animals , Benzodiazepines/metabolism , Flumazenil/pharmacokinetics , Buprenorphine/metabolism , Positron-Emission Tomography/methods , Diazepam/metabolism , Receptors, GABA-A/metabolism , Brain/diagnostic imaging , Brain/metabolismABSTRACT
Peganum harmala L. and Lavandula angustifolia are two traditional herbs with probable antiseizure effects. This study evaluated the effects of these two herbal extracts on pentylenetetrazol- (PTZ-) induced seizures in mice. We prepared hydroalcoholic extracts using P. harmala seeds and the aerial parts of L. angustifolia and then randomly divided 190 mice into 19 groups. Normal saline (10 mg/kg), diazepam (2 mg/kg), P. harmala (2.5, 5, 10, 15, 30, 45, and 60 mg/kg), and L. angustifolia (200, 400, 600, and 800 mg/kg) were intraperitoneally (IP) administrated 30 min before an IP administration of PTZ (90 mg/kg). Animals were observed for behavioral changes for one hour. In addition, the effects of flumazenil and naloxone on the antiseizure activity of P. harmala and L. angustifolia were assessed. P. harmala showed antiseizure activity at the dose of 10 mg/kg; it prolonged the seizure latency and decreased the seizure duration. The mortality protection rate was 90% for this herbal extract. L. angustifolia (600 mg/kg) prolonged the seizure latency and decreased both seizure duration and mortality. Neither flumazenil nor naloxone significantly reversed the antiseizure activities of P. harmala and L. angustifolia. In mice, the hydroalcoholic extracts of P. harmala and L. angustifolia showed antiseizure activity against PTZ-induced seizures. We could not delineate the exact antiseizure mechanisms of these extracts in the current study.