Propofol Administration Research Articles

On the Use of FOPID Controllers for Maintenance Phase of General Anesthesia

This paper investigates the performance achievable with a fractional-order PID regulator controlling the Depth of Hypnosis (measured via the Bispectral Index Scale) through the administration of propofol during the maintenance phase of total intravenous anesthesia. In particular, two different methodologies were applied to tune the controller: in the first case, genetic algorithms (GAs) were used to minimize the integrated absolute error, while in the second case, the isodamping approach—a method that targets phase margin invariance with respect to the process dc gain—was employed. In both cases, the performance was extensively analyzed and compared with that of a standard PID controller by simulating multiple patients through a Monte Carlo method. The results demonstrate that a fractional-order PID controller can be effectively used to control the Depth of Hypnosis, but the improvement with respect to a standard PID controller is marginal.

Clinical Experience of Use of Kampo Medicine Shakuyakukanzoto for Muscle Spasms Caused by Tetanus.

Background Tetanus is an infectious disease caused by Clostridium tetani, which produces tetanospasmin. Intensive care using sedatives and muscle relaxants is required for the management of severe tetanus, however, long-term use of those medicines is associated with the occurrence of post-intensive care syndrome (PICS). Shakuyakukanzoto (SKT), which is clinically used for the treatment of pain associated with sudden myospasm widely, is one of Kampo medicines, and some studies showed that they are effective in treating muscle spasms caused by tetanus. The purpose of this study is to evaluate the usefulness of SKT in the management of tetanus patients from the viewpoint of the reduction of sedatives. Methods Patients who were diagnosed with tetanus and were treated in our hospital between January 2006 and December 2022 were included. Patients were divided into two groups, patients treated with SKT and those without SKT, and the background information and clinical courses, especially the reduction of sedatives, were compared between the two groups. Results There were five tetanus patients who were treated with SKT (SKT(+) group) and two tetanus patients without SKT (SKT(-) group), respectively. Intubation and mechanical ventilation were required for the management of generalized seizures in all seven patients, who were admitted to the intensive care unit (ICU). The administration of propofol could be discontinued after an average of 8.6 days (range: 3-22 days) from the initiation of SKT administration. The dosage of propofol was lower in patients who received SKT versus those who did not; midazolam and fentanyl exhibited a similar tendency. The mean durations of ICUand hospital stays for patients treated with or without SKT were almost equal (the mean durations of ICU stay in SKT(+) and SKT(-) groups were 22.6 and 24.0 days, and those of hospital stay in SKT(+) and SKT(-) groups were 35.2 and 36.0 days, respectively). All seven patients were discharged and transferred to another hospital for rehabilitation. Conclusions SKT may be useful in the management of myospasms in patients with tetanus. It may also prevent the occurrence of PICU in patients with tetanus who require intensive care by reducing the use of sedatives and analgesics.

Comparison of hemodynamic changes with general or local anesthesia during dental treatment in pediatric patients: A prospective clinical study.

Severe hemodynamic fluctuations during dental treatment can trigger highly undesirable physical reactions. A study was made to determine whether the administration of propofol and sevoflurane contributes to the stabilization of hemodynamic parameters during dental treatment in pediatric patients versus the use of local anesthesia alone. Forty pediatric patients needing dental treatment were assigned to either general anesthesia with local anesthesia (study group [SG]) or local anesthesia alone (control group [CG]). Two percent sevoflurane in oxygen (100% oxygen, 5 L/min) and continuous propofol infusion (target-controlled infusion [TCI], 2 μg/mL) were used as general anesthesia agents in SG; and 2% lidocaine with 1:80,000 adrenaline was used as local anesthesia in both groups. Heart rate, blood pressure and oxygen saturation were measured before starting dental treatment (baseline) and every 10 min during dental treatment. Blood pressure (p<.001), heart rate (p=.021) and oxygen saturation (p=.007) decreased substantially after the administration of general anesthesia. The levels of these parameters subsequently remained low and then recovered at the end of the procedure. On the other hand, the oxygen saturation values remained closer to baseline in SG versus CG. In contrast, the hemodynamic parameters experienced lesser fluctuations in CG than in SG. General anesthesia affords more favorable cardiovascular parameters during the entire dental treatment in comparison to local anesthesia alone (blood pressure and heart rate decrease significantly and oxygen saturation proves more stable and with values closer to baseline), and allows dental treatment to be performed on healthy, lacking cooperative ability children who otherwise could not be treated with local anesthesia alone. No side effects were observed in either group.

Noninvasive Cardiac Output Monitoring (NICOM) in the Critically Ill Patient Undergoing Endotracheal Intubation: A Prospective Observational Study.

Background: Cardiovascular instability occurring during endotracheal intubation (ETI) in the critically ill is a commonly recognized phenomenon. However, this complication has not been evaluated in terms of the physiological cause (ie, decreased preload, contractility, or afterload) leading to the instability. Thus, the aim of the current investigation was to describe the hemodynamics occurring during ETI with noninvasive physiologic monitoring and to collect preliminary data on the hemodynamic effects of induction agents and positive pressure ventilation. Methods: A multicenter prospective study enrolling adult (≥18 years) critically ill patients undergoing ETI with noninvasive cardiac output monitoring in a medical/surgical intensive care unit from June 2018 to May 2019 was conducted. This study used the Cheetah Medical noninvasive cardiac output monitor to collect hemodynamic data during the peri-intubation period. Additional data collected included baseline characteristics such as illness severity, peri-intubation pharmacologic administration, and mechanical ventilation settings. Results: From the original 27 patients, only 19 (70%) patients had complete data and were included in the final analysis. Propofol was the most common sedative 8 (42%) followed by ketamine 6 (32%) and etomidate 5 (26%). Patients given propofol demonstrated a decrease in total peripheral resistance index (delta change [dynes × s/cm-5/m2]: -2.7 ± 778.2) but stabilization in cardiac index (delta change (L/min/m2]: 0.1 ± 1.5) while etomidate and ketamine demonstrated increases in total peripheral resistance index (etomidate delta change [dynes × s/cm-5/m2]: 302.1 ± 414.3; ketamine delta change [dynes × s/cm-5/m2]: 278.7 ± 418.9) but only etomidate resulted in a decrease in cardiac index (delta change [L/min/m2]: -0.3 ± 0.5). Positive pressure ventilation resulted in minimal changes to hemodynamics during ETI. Conclusions: The current study demonstrates that although propofol administration leads to a decrease in total peripheral resistance index, cardiac index is maintained while etomidate leads to a decrease in cardiac index with both etomidate and ketamine increasing total peripheral resistance index. These hemodynamic profiles are minimally affected by positive pressure ventilation. Study registration: ClinicalTrials.gov ID, NCT03525743.

OUTCOMES OF ERCP WITH NON-ANESTHESIOLOGIST ADMINISTERED PROPOFOL (NAAP)

OUTCOMES OF ERCP WITH NON-ANESTHESIOLOGIST ADMINISTERED PROPOFOL (NAAP)

Propofol anesthesia decreases the incidence of new-onset postoperative atrial fibrillation compared to desflurane in patients undergoing video-assisted thoracoscopic surgery: A retrospective single-center study.

Postoperative atrial fibrillation (POAF) increases postoperative morbidity, mortality, and length of hospital stay. Propofol is reported to modulate atrial electrophysiology and the cardiac autonomic nervous system. Therefore, we retrospectively examined whether propofol suppresses POAF in patients undergoing video-assisted thoracoscopic surgery (VATS) compared to desflurane. We retrospectively recruited adult patients who underwent VATS during the period from January 2011 to May 2018 in an academic university hospital. Between continuous propofol and desflurane administration during anesthetic maintenance, we investigated the incidence of new-onset POAF (within 48 hours after surgery) before and after propensity score matching. Of the 482 patients, 344 received propofol, and 138 received desflurane during anesthetic maintenance. The incidence of POAF in the propofol group was less than that in the desflurane group (4 [1.2%] vs. 8 patients [5.8%], odds ratio [OR]; 0.161, 95% confidence interval (CI), 0.040-0.653, p = 0.011) in the present study population. After adjustment for propensity score matching (n = 254, n = 127 each group), the incidence of POAF was still less in propofol group than desflurane group (1 [0.8%] vs. 8 patients [6.3%], OR; 0.068, 95% CI: 0.007-0.626, p = 0.018). These retrospective data suggest propofol anesthesia significantly inhibits POAF compared to desflurane anesthesia in patients undergoing VATS. Further prospective studies are needed to elucidate the mechanism of propofol on the inhibition of POAF.

COMPARISON OF EFFICACY OF INTRAVENOUS LIGNOCAINE VERSUS BUTORPHANOL AS PRETREATMENT IN REDUCING PAIN DUE TO PROPOFOL INJECTION.

Background And Aims: Propofol is almost an ideal intravenous anesthetic agent but pain on injection becomes a major side effect. This study compares the efcacy of lignocaine and butorphanol in reducing the pain on propofol injection. Methods: After obtaining approval from institutional ethical committee and consent, hundred patients aged between 18 to 60 years, belonging to ASA physical status I and II posted for elective surgeries were randomly allocated into two groups of 50 each, group L received intravenous Lignocaine 40mg and group B received Butorphanol 2mg with manual venous occlusion one minute prior to propofol administration. The grade of the pain was assessed using Mc Crirrick and Hunter scale. Hemodynamic parameters were also monitored. Analysis was done by SPSS software. Chi square test and Fisher exact test was used for incidence of pain and severity of pain respectively. P value &lt;0.05 was considered statistically signicant. Results: Both the groups were similar with respect to demographic variables. The incidence of pain was 18% in group receiving butorphanol and 38% in group receiving lignocaine with p value of 0.026. The severity of pain, grade I was 18% in group receiving butorphanol and 26% in group receiving lignocaine, the severity of pain, grade II was 12% in group receiving lignocaine and 0% in group receiving butorphanol with p value of 0.014. Conclusion: Pretreatment with Butorphanol 2mg is more effective than 2% lidocaine (40 mg) in minimizing the incidence and severity of pain associated with propofol injection.

Low-Dose Propofol with Peribulbar Anaesthesia for Cataract Surgery

In this paper, we investigate the effect of sedation using low-dose propofol on patient reported outcome measures (PROMS) in patients undergoing cataract surgery. This is a randomised, single-blinded observational prospective study. Patients undergoing elective cataract surgery using peribulbar anaesthesia over consecutive cataract lists were selected for this trial. Patients were randomised to receive either no sedation or low-dose propofol (20 to 30 mg followed by 10 mg increments until the patient developed slurred speech alone) prior to the administration of local anaesthesia. Pain, satisfaction, anxiety, needle recall, pulse, and blood pressure (BP) were measured. A total of 97 patients were included, 50 of whom received propofol. There were 4 senior surgeons and anaesthetists. There were no ocular or systemic complications and all patients had uncomplicated surgery. Anxiety (p = 0.026), needle recall (p < 0.001), difference in systolic BP (p = 0.043), and pulse (p = 0.046) were dependent on patient age (p < 0.001) and the use of propofol (p = 0.007). Lower pain was associated with propofol (p = 0.008), as well as lower anxiety (p = 0.002), and increased patient age (p = 0.014). The administration of propofol was significantly associated with lower needle recall (p < 0.001), pre- to post-operative difference in systolic BP (p = 0.029), and mean BP (p = 0.044). Low-dose propofol given immediately prior to administration of local anaesthesia was associated with reduced pain and needle recall, as well as lower BP.

A Case Report: Anaesthesia for Awake Craniotomy

Background: Awake craniotomy is a neurosurgical technique that enables the precise localization of functional neural networks through intraoperative brain mapping and real-time monitoring. This operative method has been popularized in recent years due to decreased postoperative morbidities. We present a case of 31 years old female who was presented with episodes of generalized tonic colonic seizures. She had a history of recurring seizures occurring 2 to 3 times a week. Upon further investigations, she was diagnosed with brain space-occupying lesions initially suspected as low-grade glioma. Considering lesion site, the patient was deemed a suitable candidate for an awake craniotomy. To achieve conscious sedation, the patient received infusions of Remifentanil and Propofol at varying rates. During the procedure, the patient was under sedation and regularly tested for response to predetermined commands. The tumour was successfully excised by using a combination of local anaesthesia on the scalp and the administration of propofol and boluses through a systemic infusion. This case report highlights the importance of the team work among anaesthesia and surgeons where local /regional anaesthesia can be combined with sedation to perform a surgical procedure in certain conditions.

Characterizing brain dynamics during ketamine-induced dissociation and subsequent interactions with propofol using human intracranial neurophysiology

Ketamine produces antidepressant effects in patients with treatment-resistant depression, but its usefulness is limited by its psychotropic side effects. Ketamine is thought to act via NMDA receptors and HCN1 channels to produce brain oscillations that are related to these effects. Using human intracranial recordings, we found that ketamine produces gamma oscillations in prefrontal cortex and hippocampus, structures previously implicated in ketamine’s antidepressant effects, and a 3 Hz oscillation in posteromedial cortex, previously proposed as a mechanism for its dissociative effects. We analyzed oscillatory changes after subsequent propofol administration, whose GABAergic activity antagonizes ketamine’s NMDA-mediated disinhibition, alongside a shared HCN1 inhibitory effect, to identify dynamics attributable to NMDA-mediated disinhibition versus HCN1 inhibition. Our results suggest that ketamine engages different neural circuits in distinct frequency-dependent patterns of activity to produce its antidepressant and dissociative sensory effects. These insights may help guide the development of brain dynamic biomarkers and novel therapeutics for depression.

Propofol exerts anti-anhedonia effects via inhibiting the dopamine transporter

Lasker's award-winning drug propofol is widely used in general anesthesia. The recreational use of propofol is reported to produce a well-rested feeling and euphoric state; yet, the neural mechanisms underlying such pleasant effects remain unelucidated. Here, we report that propofol actively and directly binds to the dopamine transporter (DAT), but not the serotonin transporter (SERT), which contributes to the rapid relief of anhedonia. Then, we predict the binding mode of propofol by molecular docking and mutation of critical binding residues on the DAT. Fiber photometry recording on awake freely moving mice and [18F] FP-CIT-PET scanning further establishes that propofol administration evokes rapid and lasting dopamine accumulation in nucleus accumbens (NAc). The enhanced dopaminergic tone drives biased activation of dopamine-receptor-1-expressing medium spiny neurons (D1-MSNs) in NAc and reverses anhedonia in chronically stressed animals. Collectively, these findings suggest the therapeutic potential of propofol against anhedonia, which warrants future clinical investigations.

EEG responses to standardised noxious stimulation during clinical anaesthesia: a pilot study.

During clinical anaesthesia, the administration of analgesics mostly relies on empirical knowledge and observation of the patient's reactions to noxious stimuli. Previous studies in healthy volunteers under controlled conditions revealed EEG activity in response to standardised nociceptive stimuli even at high doses of remifentanil and propofol. This pilot study aims to investigate the feasibility of using these standardised nociceptive stimuli in routine clinical practice. We studied 17 patients undergoing orthopaedic trauma surgery under general anaesthesia. We evaluated if the EEG could track standardised noxious phase-locked electrical stimulation and tetanic stimulation, a time-locked surrogate for incisional pain, before, during, and after the induction of general anaesthesia. Subsequently, we analysed the effect of tetanic stimulation on the surgical pleth index as a peripheral, vegetative, nociceptive marker. We found that the phase-locked evoked potentials after noxious electrical stimulation vanished after the administration of propofol, but not at low concentrations of remifentanil. After noxious tetanic stimulation under general anaesthesia, there were no consistent spectral changes in the EEG, but the vegetative response in the surgical pleth index was statistically significant (Hedges' g effect size 0.32 [95% confidence interval 0.12-0.77], P=0.035). Our standardised nociceptive stimuli are not optimised for obtaining consistent EEG responses in patients during clinical anaesthesia. To validate and sufficiently reproduce EEG-based standardised stimulation as a marker for nociception in clinical anaesthesia, other pain models or stimulation settings might be required to transfer preclinical studies into clinical practice. DRKS00017829.

Pharmacokinetics of intravenous propofol in southern white rhinoceros (Ceratotherium simum simum) after intramuscular etorphine-butorphanol-medetomidine-azaperone.

To determine the pharmacokinetics of a single bolus of intravenous (IV) propofol after intramuscular administration of etorphine, butorphanol, medetomidine, and azaperone in 5 southern white rhinoceros to facilitate reproductive evaluations. A specific consideration was whether propofol would facilitate timely orotracheal intubation. 5 adult, female, zoo-maintained southern white rhinoceros. Rhinoceros were administered etorphine (0.002 mg/kg), butorphanol (0.02 to 0.026 mg/kg), medetomidine (0.023 to 0.025 mg/kg), and azaperone (0.014 to 0.017 mg/kg) intramuscularly (IM) prior to an IV dose of propofol (0.5 mg/kg). Physiologic parameters (heart rate, blood pressure, respiratory rate, and capnography), timed parameters (eg, time to initial effects and intubation), and quality of induction and intubation were recorded following drug administration. Venous blood was collected for analysis of plasma propofol concentrations using liquid chromatography-tandem mass spectrometry at various time points after propofol administration. All animals were approachable following IM drug administration, and orotracheal intubation was achieved at 9.8 ± 2.0 minutes (mean ±SD) following propofol administration. The mean clearance for propofol was 14.2 ± 7.7 ml/min/kg, the mean terminal half-life was 82.4 ± 74.4 minutes, and the maximum concentration occurred at 2.8 ± 2.9 minutes. Two of 5 rhinoceros experienced apnea after propofol administration. Initial hypertension, which improved without intervention, was observed. This study provides pharmacokinetic data and insight into the effects of propofol in rhinoceros anesthetized using etorphine, butorphanol, medetomidine, and azaperone. While apnea was observed in 2 rhinoceros, propofol administration allowed for rapid control of the airway and facilitated oxygen administration and ventilatory support.

Paraventricular thalamus controls consciousness transitions during propofol anaesthesia in mice

BackgroundThe neuronal mechanisms underlying propofol-induced modulation of consciousness are poorly understood. Neuroimaging studies suggest a potential role for non-specific thalamic nuclei in propofol-induced loss of consciousness. We investigated the contribution of the paraventricular thalamus (PVT), a midline thalamic nucleus that has been implicated in arousal control and general anaesthesia with inhaled anaesthetics, to loss and recovery of consciousness during propofol anaesthesia. MethodsPolysomnographic recordings and righting reflex test were used to determine the transitions of loss and recovery of righting reflex, used as a measure of consciousness in mice, during propofol anaesthesia in mice under conditions mimicking clinical propofol administration. PVT neuronal activities were monitored using fibre photometry and regulated using optogenetic and chemogenetic methods. ResultsPopulation activities of PVT glutamatergic neurones began to decrease before propofol-induced loss of consciousness and rapidly increased to a peak at the onset of recovery of consciousness. Chemogenetic inhibition of PVT calretinin-expressing (PVTCR) neurones shortened onset (from 176 [35] to 127 [26] s; P=0.001) and prolonged return (from 1568 [611] to 3126 [1616] s; P=0.002) of righting reflex. Conversely, chemogenetic activation of PVTCR neurones exerted opposite effects. Furthermore, optogenetic silencing of PVTCR neurones accelerated transitions to loss of consciousness (from 205 [35] to 158 [44] s; P=0.027) and slowed transitions to recovery of consciousness (from 230 [78] to 370 [99] s; P=0.041). During a steady period of unconsciousness maintained with continuous propofol infusion, brief optical activation of PVTCR neurones restored cortical activity and arousal with a latency of about 5 s. ConclusionsThe paraventricular thalamus contributes to the control of consciousness transitions in propofol anaesthesia in mice. This provides a potential neuroanatomical target for controlling consciousness to reduce anaesthetic dose requirements and side effects.

The Development and Optimization of Lipid-Based Self-Nanoemulsifying Drug Delivery Systems for the Intravenous Delivery of Propofol.

Propofol is a relatively short-acting potent anesthetic lipophilic drug used during short surgical procedures. Despite the success of propofol intravenous emulsions, drawbacks to such formulations include inherent emulsion instability, the lack of a safe vehicle to prevent sepsis, and concern regarding hyperlipidemia-related side effects. The aim of the current investigation was to develop a novel, lipid-based self-nanoemulsifying drug delivery system (SNEDDS) for propofol with improved stability and anesthetic activity for human use. A series of SNEDDS formulations were developed using naturally obtained medium-chain/long-chain mono-, di-, and triglycerides, glyceryl monocaprylate, and water-soluble cosolvents with hydrogenated castor oil constructing ternary phase diagrams for propofol. The developed SNEDDS formulations were characterized using visual observation, particle size analysis, zeta potential, transmission electron microscopy, equilibrium solubility, in vitro dynamic dispersion and stability, and in vivo sleeping disorder studies in rats. The in vivo bioavailability of the SNEDDSs in rats was also studied to compare the representative formulations with the marketed product Diprivan®. Medium-chain triglycerides (M810) with mono-diglycerides (CMCM) as an oil blend and hydrogenated castor oil (KHS15) as a surfactant were selected as key ingredients in ternary phase diagram studies. The nanoemulsifying regions were identified from the studies and a number of SNEDDSs were formulated. Results from the characterization studies demonstrated the formation of efficient nanosized particles (28-45 nm globule size, 0.10-0.20 PDI) in the optimized SNEDDS with a drug loading of 50 mg/g, which is almost 500-fold higher than free propofol. TEM analysis showed the formation of spherical and homogeneous nanoparticles of less than 50 nm. The dissolution rate of the representative SNEDDS was faster than raw propofol and able to maintain 99% propofol in aqueous solution for around 24 h. The optimized liquid SNEDDS formulation was found to be thermodynamically stable. The intravenous administration of the SNEDDS in male Wistar rats induced a sleeping time of 73-88 min. The mean plasma concentrations after the IV administration of propofol nano-formulations PF2-SNEDDS and PF8-SNEDDS were 1348.07 ± 27.31 and 1138.66 ± 44.97 µg/mL, as compared to 891.44 ± 26.05 µg/mL (p = 0.05) observed after the IV administration of raw propofol. Propofol-loaded SNEDDS formulations could be a potential pharmaceutical product with improved stability, bioavailability, and anesthetic activity.

The Role of Analgesia in the Identification and Treatment of Digestive Tract Lesions: A Randomized, Prospective, Double-Blind Study.

The association of sedation with analgesia in endoscopic procedures represents the ideal combination of anesthetic drugs, which allows these exploratory procedures to be carried out safely, in an outpatient setting. The aim of this study is to compare the results of the use of simple Propofol or Propofol associated with Fentanyl in order to ensure optimal sedation necessary for the detection of benign or malignant lesions of the digestive tract. In this study, 80 patients aged between 18 and 80 years were included, 40 in Group 1 who were administered Propofol alone and 40 in Group 2 in which Propofol was administered associated with Fentanyl. The onset of anesthetic sleep was 19.3±5.1 seconds in Lot 2 versus 29.6±9.1 seconds in Lot 1. The average dose of Propofol used was 203.6±82.8 mg in Lot 1 and in Lot 2 it was lower, 166.3±8.3mg. Cardio respiratory changes were more frequent in Lot 2. The wake-up time was 3.2±1.2 minutes in Lot 1 as a result of the administration of Propofol alone and 7±1.4 minutes in Lot 2. The discharge time was equal for patients in both groups. The degree of postanesthesia safisfaction was 10 for all patients from Lot 2, due to the analgesia provided by the administration of Fentanyl. The use of Propofol associated with Fentanyl in gastrointestinal endoscopic procedures is associated with a rapid recovery of cognitive function at the time of discharge and minimal adverse events, ensuring optimal conditions of analgesia and stability of vital functions.

Wide-Awake Olecranon Fracture Fixation: Is it Possible?

The wide-awake local anesthesia no tourniquet technique has been widely performed in hand and wrist surgery with remarkable results. However, its use on the elbow has rarely been reported. Here we describe the use of wide-awake local anesthesia no tourniquet in olecranon fracture fixation in 4 cases. Tumescent anesthesia was injected from the proximal ulna to approximately 10 cm distally and into the periosteum and fracture site, approximately 25 minutes before skin incision. The fracture underwent closed reduction and was fixed using a long 6.5-mm cancellous screw with a washer through a small incision. No tourniquet was applied and none or mild sedation was administered. At the end of the operation, patients were asked to perform active elbow flexion-extension and forearm pronosupination movements under an image intensifier to test the range of motion and fracture stability. The surgical procedure was completed in all 4 cases. Two patients reported mild pain during ulnar medullary canal reaming, with pain scores of 3 and 4 on a 10-point scale, respectively. One case was resolved with additional local anesthetic injection. The other case required the administration of intravenous propofol. Both patients were able to actively move the elbow at the end of the operation. The use of wide-awake local anesthesia no tourniquet for olecranon fracture fixation has the advantage of obviating the need for an arm tourniquet, general anesthesia or heavy sedation, preoperative tests, and discontinuing routine medications (including anticoagulants). The stability of the elbow fixation was tested by active motion during surgery. This simple, safe, low-cost, and reproducible technique may be a good option for patients with contraindications or high risk of general or regional nerve block anesthesia. Therapeutic IV.

Citrobacter freundii induces sepsis with new-onset status seizure in an adult: A case report and literature review.

Sepsis with brain abscess induced by Citrobacter freundii in adults has rarely been reported and is extremely pathogenic with a high mortality rate. Early diagnosis of the infection still remains challenging. A 27-year-old woman was transferred to our emergency department for fever, status seizure and refractory hypotension. Administration of midazolam, propofol and sodium valproate could not attenuate the seizure except for the addition of vecuronium. The blood white blood cell count was 42.91 (109/L) with 80% neutrophils, and procalcitonin was 22.46ng/mL. Both deoxyribonucleic acid and ribonucleic acid of C freundii were detected in blood by metagenomic next-generation sequencing of pathogens,the diagnosis of septic shock and brain abscess caused by C freundii was highly suspected. On day 1, antibiotics of cefoperazone sodium and sulbactam sodium 6g/day, immunoglobulin, and hydrocortisone were used with suspected septic shock. Continuous renal replacement therapy was used to eliminate excessive lactate, ammonia, myohemoglobin and creatinine. On day 2, a brain computed tomography scan revealed multiple patchy slightly low densities in the brain, antibiotics were adjusted to meropenem intravenously 3g/day. On day 2, a brain computed tomography scan revealed multiple patchy slightly low densities in the brain, she died on day 3. Clinicians should consider the possibility of brain abscess when evaluating a patient with new-onset dizziness, fever, seizure, or other neurologic symptoms or signs, especially for patients whose mental status changes. metagenomic next generation sequencing and resistance genes could be considered when cerebrospinal fluid or blood results are negative and clinical manifestations are highly suspected of infection or when the treatment time is limited.

Dexmedetomidine decreases the 50% effective dose (ED50) of intravenous propofol required to prevent tracheal intubation response in Beagles.

To determine the 50% effective dose (ED50) of intravenous propofol required for successfully preventing tracheal intubation response in Beagles co-induced with dexmedetomidine. 36 adult male Beagles. The dogs were randomly assigned to either group D1, group D2, or group C (received 1 µg/kg, 2 µg/kg dexmedetomidine intravenously, or the same amount of normal saline as dexmedetomidine, 10 mL). The first dog in each group received 6 mg/kg of propofol for induction. The pump speed of propofol was 600 mL/h. The dosage varied with increments or decrements of 0.5 mg/kg based on the Dixon up-and-down method. The duration of eye-opening after propofol administration was recorded. Changes in heart rate (HR) and respiratory rate (RR) were recorded at 5 timepoints: after entering the operation room and prior to propofol administration (T1), 1 and 3 min after propofol administration (T2 and T3), 3 and 5 min after intubation (T4 and T5). The required ED50 of propofol that prevented tracheal intubation response in D1, D2, and C groups were 6.4 mg/kg (95% CI, 6.1 to 6.7 mg/kg), 5.8 mg/kg (95% CI, 5.67 to 6 mg/kg), and 8.3 mg/kg (95% CI, 8 to 8.5 mg/kg), respectively. The recovery time of group D2 was significantly longer than that of groups D1 and C (P < .05). The differences in HR among the 3 groups were significant from T2 up to T5 timepoint (P < .05). The differences in RR among the 3 groups were significant at T2 and T3 timepoints (P < .05). Dexmedetomidine pre-injection reduces the amount of propofol required for endotracheal intubation response in Beagles, thereby reducing the respiratory inhibition induced by propofol.

Modifications in gamma-aminobutyric acid type A receptor subunit gene expression after macrophage differentiation and propofol administration in THP-1 cells

Modifications in gamma-aminobutyric acid type A receptor subunit gene expression after macrophage differentiation and propofol administration in THP-1 cells