Anesthetic Conditions Research Articles

Control Mechanisms of Sensorimotor System on Manipulation of Proprioceptive Inputs During Balance Maintenance

Proprioceptive inputs have crucial roles in control of the posture. The aim of the present study was to assess the effect of interfering with these signals on postural stability by ice-induced anaesthesia and local calf muscle fatigue. Seventeen healthy young individuals participated in this study to stand quietly and on an unstable platform under normal, anaesthesia, and fatigue conditions. A force platform calculated excursions of centre of pressure. Stabilogram-diffusion analysis was utilised to evaluate how body controls the posture with and without proprioceptive inputs. Time intervals of using the sensory feedback is significantly increased by anaesthesia in quiet standing (430 ms, p = 0.034) to note more delayed use of sensory information in a closed-loop. Additionally, fatigue significantly increased the time intervals of using sensory feedback during standing on the unstable platform (290 ms, p = 0.016). Interestingly, sensory interventions had no effect on the stability of the open-loop control of posture (short-term control), but they significantly influenced the closed-loop control (long-term control) (p < 0.004). Specifically, fatigue led to increased instabilities when the body used sensory inputs during both quiet standing (p = 0.021) and standing on the unstable platform (p = 0.041). These findings highlight the importance of proprioception in balance control for healthy individuals. Interfering with proprioceptive inputs, either through anaesthesia or fatigue, resulted in instabilities during balance maintenance. Our study provides new insights into the mechanisms underlying postural control, emphasising the significance of proprioceptive inputs. Understanding how proprioception affects balance maintenance may have implications for rehabilitation strategies, injury prevention, and the development of interventions to improve postural stability.

A novel method for the measurement of cardiovascular responses to lower body negative pressure in the awake instrumented rat.

Lower body negative pressure (LBNP) has been used for decades in humans to model arterial baroreceptor unloading and represents a powerful tool for evaluating cardiovascular responses to orthostatic challenges. However, LBNP studies in animals have been limited to conditions of anesthesia or sedation, where cardiovascular reflexes are altered. Given the consequent uncertainties, the usefulness of LBNP studies in these preclinical models has been severely hampered. Here, we developed an approach using a novel system to study LBNP responses in awake rats instrumented for telemetric blood pressure (BP) measurement. BP responses to progressive levels of LBNP (-3 to -15 mmHg) were first made in awake rats, followed by measurements under various treatments. In awake untreated rats, BP was well maintained up to -15 mmHg LBNP and there was a robust baroreceptor response in heart rate (HR). Under anesthesia with 3% isoflurane, BP was not maintained at LBNP below -3 mmHg and baroreceptor responses in HR were completely blocked, confirming the limited usefulness of this method under anesthesia. Interrogation of the autonomic pathways involved in the response revealed that muscarinic (atropine) and β1-adrenergic (atenolol) blockade, separately or together, blocked the HR responses, but BP remained well maintained. α1-adrenergic blockade (prazosin) severely blunted the ability to maintain BP in response to LBNP. These data are consistent with findings in human subjects in that the vascular component of the orthostatic reflex predominates in preserving BP. Validation of this novel method provides a valuable tool for investigating orthostatic (in)tolerance in a facile preclinical model.NEW & NOTEWORTHY Orthostatic hypotension or intolerance is a common but often underappreciated disorder that is associated with a variety of neurological comorbidities. LBNP studies provide a valuable tool to study these conditions, but heretofore could only be used in human subjects, since animal subjects needed to be anesthetized or sedated, which blunts or eliminates neurocardiovascular reflexes. This novel method allowing LBNP studies in awake rats will provide a valuable preclinical model for studying these disorders.

Perivascular space imaging during therapy for medulloblastoma.

Perivascular spaces (PVS) are fluid filled compartments surrounding the small blood vessels in the brain. The impact of radiotherapy and chemotherapy on PVS remains unclear. The aim of this study is to investigate treatment effects of radiotherapy and chemotherapy at four time points (TPs) in pediatric medulloblastoma (MB) patients. We examined 778 scans from 241 MB patients at baseline (0M), after 12 weeks (about 3 months) of radiotherapy and rest (3M), after chemotherapy completion (12M), and a follow-up (FollowUp) at 18- or 21-months post-baseline. PVS was segmented by applying Frangi filter on the white matter regions on T1 weighted images acquired at 3T Siemens MRI scanner using MPRAGE. PVS volume and ratio, defined as the ratio of PVS volume to the white matter volume, were measured at the four TPs. The data was first statistically analyzed using a full model where all data were included, then a paired model, which included only patients who completed consecutive measurements under the same anesthesia and shunt conditions. Both the full model and paired model showed that PVS (including ratio and volume) increased at 3M post-radiotherapy compared to baseline. During chemotherapy, PVS decreased significantly from 3M to 12M. Subsequently, from 12M to FollowUp, PVS increased again. MRI exams under anesthesia exhibited significantly lower PVS than those without anesthesia. Patients who had undergone a shunt procedure exhibited a significantly reduced PVS compared to those who had not undergone the procedure. We concluded that craniospinal irradiation led to an elevated PVS. Conversely, chemotherapy or time post-irradiation decreased PVS. Anesthesia and shunt procedures can also influence perivascular space ratio or volume.

Optimization of inhaled anesthesia for Octodon degus using electroencephalography

Physiological responses to inhaled anesthetics vary among species. Therefore, a precise anesthetic technique is important for each individual species. In this study, we focused on the degu (Octodon degus), a small herbivorous rodent. Degus have recently begun to be used as laboratory models for brain research because of certain human-like characteristics, such as spontaneous development of Alzheimer's disease. In this study, we evaluated appropriate induction and maintenance anesthesia conditions for isoflurane and sevoflurane in degus by a stimulation test, electroencephalography (EEG), minimum alveolar concentration (MAC), and vital signs. During induction, more rapid time to loss of the righting reflex and deeper anesthesia in degus were observed in isoflurane. The MAC value for degus were 1.75 ± 0.0% in isoflurane and 2.25 ± 0.27% in sevoflurane. Whereas some degus were awake during maintenance anesthesia using both anesthetics at concentrations of ≤2%, no rats were awake when using sevoflurane at a concentration of 2%. The duration of the total flat EEG, a measure of the depth of maintenance anesthesia, was longer for isoflurane than for sevoflurane. Furthermore, higher concentrations of both anesthetics suppressed the respiratory rate in degus. These new findings regarding inhalation anesthesia in degus will contribute to future developments in the fields of laboratory animals and veterinary medicine.

A Comparison of Dexmedetomidine and Magnesium Sulfate as an Anesthetic Adjuvant in Trans-Sphenoidal Pituitary Surgery

Background: Trans-sphenoidal pituitary surgery is a minimally invasive procedure used for pituitary disorders. Objectives: This study aims to investigate the effects of dexmedetomidine and magnesium sulfate in improving anaesthesia conditions and pain control during trans-sphenoidal pituitary surgery. Methods: This prospective randomised clinical trial included 90 patients between 18 and 65 years of age, with American Society of Anaesthesiologists (ASA) physical status I and II, who were undergoing elective trans-sphenoidal pituitary surgery. Exclusion criteria included a change in surgical technique during surgery and patients who were transferred directly to the ICU with a tracheal tube. Patients were randomly assigned to three groups (group D: Dexmedetomidine, group M: Magnesium sulfate, and group C: Control), and various parameters such as haemodynamics, surgical field evaluation, and pain were assessed. Results: Ninety consecutive patients were included in this study. Forty-seven males (52.2%) and 43 females (47.8%) were evaluated. There were no significant differences among the three groups regarding gender distribution, age, or Body Mass Index (BMI). The mean age of the included patients was 46.27 ± 12.47 years. The measured mean arterial pressure was lower in group D compared to group M (P-value = 0.005). The other variable that statistically differed between the two groups was the numerical rating scale, which was lower in group D (P-value = 0.02). All measured variables in group D and group M were significantly lower compared to the control group, except for the extubation time. Conclusions: Adding dexmedetomidine as an adjuvant anaesthetic medication during trans-sphenoidal pituitary surgery could potentially enhance haemodynamic stability and improve surgeon satisfaction scores.

Effect of use of cuffed endotracheal tubes on the occurrence of postoperative extubation-related respiratory adverse events in pediatric patients with airway hypersensitivity: a retrospective cohort study.

Whether endotracheal tube (ETT) configuration (cuffed or uncuffed) influences the occurrence of respiratory adverse events (RAEs) in patients at risk remains largely unknown. We investigated the effects of cuffed ETTs on RAE occurrence after extubation in pediatric patients with airway hypersensitivity. Children aged < 8years with increased airway hypersensitivity (defined as upper airway symptoms, recent upper respiratory infection within 2weeks, or a history of asthma) who underwent general endotracheal anesthesia with inhaled agents between January 2021 and December 2022 were included. We retrospectively examined the patients' background and intraoperative anesthesia conditions by comparing the cuffed and uncuffed ETT groups. Multiple logistic regression analysis was performed to estimate the association between ETT configuration (cuffed vs. uncuffed) and the occurrence of RAEs or respiratory interventions (laryngospasm, peripheral capillary oxygen saturation < 92%, oxygen supplementation, epinephrine inhalation, or reintubation) after extubation. Cuffed ETTs were used in 163 patients and uncuffed ETTs in 143 patients. Apart from the frequency of upper airway surgery and intraoperative fluid balance, no significant differences in background characteristics were observed between the groups. RAEs after extubation were observed in 36 (22.1%) and 28 (19.6%) patients in each cuffed and uncuffed ETT groups. After adjusting for known RAE risk factors, no difference was observed in RAEs or respiratory interventions after extubation between both groups (odds ratio, 1.14; 95% confidence interval: 0.64, 2.06). In pediatric patients with airway hypersensitivity, the use of cuffed ETTs did not increase the occurrence of RAEs or respiratory interventions after extubation.

The Agreement Between Transthoracic and Transesophageal Echocardiography in the Assessment of Right Ventricular Diastolic Dysfunction Grades in Adult Patients Undergoing Cardiac Surgery: A Prospective Observational Study.

Introduction The importance of right ventricular (RV) diastolic function in cardiac surgery cannot be overstated, as it significantly affects prognosis and long-term outcomes. Conventionally, RV diastolic dysfunction (RVDD) is assessed and graded using criteria from either the American Society of Echocardiography (ASE) or the British Society of Echocardiography (BSE), with measurements done by transthoracic echocardiography (TTE). However, during cardiac surgery, perioperative echocardiographic evaluation is done predominantly by transesophageal echocardiography (TEE). This study aimed to assess the agreement between TTE and TEE in grading RVDD using both ASE and BSE criteria. Methods Key two-dimensional (2D) and Doppler parameters were measured in 81 patients undergoing cardiac surgery by both TTE and TEE after anesthesia induction within 10 minutes of each other, under similar hemodynamic, anesthetic, and ventilatory conditions. RVDD gradings were done separately by TTE and TEE with both ASE and BSE criteria using the measured values of the key parameters by TTE and TEE, respectively. RVDD gradings derived from TTE were compared with those derived from TEE. The tricuspid inflow Doppler and tricuspid annular tissue Doppler parameters were measured in TEE in both mid-esophageal RV inflow-outflow (MERVIO) and deep transgastric RV inflow-outflow (DTGRVIO) views. Gradings were done separately for both views of TEE by using the Doppler values measured in the respective views (TEE-MERVIO and TEE-DTGRVIO). The TTE-derived RVDD grades were compared with those derived by both TEE-MERVIO and TEE-DTGRVIO. Weighted κ values were used to assess observed agreement beyond chance. Inter-rater reliability of the RVDD grades derived by both TTE and TEE (both views) was also checked. Individual 2D and Doppler parameters were compared between TTE and TEE in terms of Bland-Altman limits of agreement. Results As per ASE criteria, disagreement of RVDD by ≥1 grade was seen in 43 (53.1%) patients and by 2 grades in eight (9%)patients when comparing TTE and TEE-MERVIO, yielding a weighted κ of 0.14 (p=0.123). Disagreement by ≥1 grade was observed in 32 (39.5%) patients and by 2 grades in 10 (12.3%) patients when comparing TTE and TEE-DTGRVIO, yielding a weighted κ of 0.3 (p=0.002). Using the BSE Criteria, disagreement of RVDD grades occurred in nine (11.1%) patients when comparing TTE and TEE-MERVIO, yielding an unweighted κ of 0.25 (p=0.295). Disagreement occurred in 12 (14.8%) patients when comparing TTE and TEE-DTGRVIO, yielding an unweighted κ of 0.260 (p=0.187). There was almost perfect agreement between independent raters regarding both TTE- and TEE-derived RVDD grades per the ASE criteria, and substantial to almost perfect agreement per BSE criteria. Bland-Altman analysis of paired data between the TTE- and TEE-measured values of individual 2D and Doppler parameters showed wide limits of agreement. Conclusions This study revealed, at best, only fair agreement between TTE and TEE in grading RVDD. The measured 2D and Doppler echocardiographic parameters showed wide limits of agreement between TTE and TEE. We recommend further researchto develop a TEE-based algorithm for grading RVDD, and to evaluate the prognostic effectiveness of perioperative TEE for predicting adverse clinical outcomes associated with RVDD.

The effectiveness of combined anesthesia in comparison with general anesthesia in thyroid and parathyroid surgery: a single-center prospective randomized study

BACKGROUND. Operations on the organs of the anterior surface of the neck (thyroidectomy, carotidectomy, plastic surgery, etc.) are widespread in the Russian Federation. The development of adequate anesthesiological support for these interventions is an urgent task of modern anesthesiology. The introduction of combined regional anesthesia techniques into surgical practice makes it possible to minimize postoperative complications, manifested in the form of severe pain syndrome, postoperative nausea and vomiting. AIM. To conduct a comparative assessment of the effectiveness of combined (general + regional) and only general anesthesia during operations on the thyroid and parathyroid glands. MATERIALS AND METHODS. In a prospective randomized study, 60 patients operated on for thyroid and parathyroid gland diseases were divided into 2 groups: in group 1, general anesthesia was performed in combination with blockade of the internal fascia of the neck and bilateral blockade of the superficial branches of the cervical plexus, as well as the Berry ligament area under ultrasound navigation; patients of group 2 were operated on in conditions of combined general anesthesia. The hemodynamic profile during surgery, plasma cortisol concentration, required doses of fentanyl, intensity of postoperative pain syndrome, need for anesthesia, and recovery time were evaluated. RESULTS. Combined (general + regional) anesthesia was characterized by a decrease in fentanyl consumption compared with the group receiving only general anesthesia (p 0.0001), a decrease in cortisol content in blood plasma 12 hours after extubation (p=0.0439), a reduction in median pain after tracheal extubation 3 and 12 hours after surgery (p=0.0190, p 0.0001), as well as a twofold reduction in the time interval from the end of the operation to the moment of extubation (p=0.0001). The assessment of patients on the Aldreth awakening scale in the group of people who underwent combined anesthesia indicates a higher willingness of patients to be transferred from the operating room to the awakening ward (p=0.0114). CONCLUSION. The study demonstrated the effectiveness and safety of the combined anesthesia technique in thyroid and parathyroid surgery, which provides adequate anesthetic protection for patients.

Effect of topical application and local infiltration of anesthetic agent on pain associated with wedging and matrix placement during proximal restoration

ABSTRACT Aims: To evaluate the pain perceived by the patient during the secured placement of the matrix and wedge under different anesthetic conditions using a visual analog scale. Methods and Material: Ninety patients with proximal surface lesions were included and assigned to three groups (n = 30). Before the matrix and wedge placement, the patient received either the anesthetic or placebo agents. VAS score measures the pain the patient perceives after the matrix and wedge placement. Statistical Analysis Used: Statistical analysis was done using the SPSS package, and the results were subjected to the Kruskal–Wallis test. Results: There was no statistically significant difference between the two groups who received one of the anesthetic agents. However, a statistically significant difference was present between the two anesthetic groups and the control group, which was chlorhexidine gel. Conclusions: Topical anesthetic gel effectively reduces pain during the placement of the matrix and wedge, resulting in better matrix band adaptation and, ultimately, the restoration’s good marginal adaptation.

Dynamic oxygen assessment techniques enable determination of anesthesia's impact on tissue.

Tissue oxygenation is well understood to impact radiosensitivity, with reports demonstrating a significant effect of breathing condition and anesthesia type on tissue oxygenation levels and radiobiological response. However, the temporal kinetics of intracellular and extracellular oxygenation have never been quantified, on the timescale that may affect radiotherapy studies. C57BL/6 mice were anesthetized using isoflurane at various percentages or ketamine/xylazine (ket/xyl: 100/10 mg/kg) (N = 48). Skin pO2 was measured using Oxyphor PdG4 and tracked after anesthetization began. Oxyphor data was validated with relative measurements of intracellular oxygen via protoporphyrin IX (PpIX) delayed fluorescence (DF) imaging. Ex vivo localization of both PdG4 Oxyphor and PpIX were quantified. Under all isoflurane anesthesia conditions, leg skin pO2 levels significantly increased from 12-15 mmHg at the start of anesthesia induction (4-6 minutes) to 24-27 mmHg after 10 minutes (p < 0.05). Ketamine/xylazine anesthesia led to skin pO2 maintained at 15-16 mmHg throughout the 10-minute study period (p < 0.01). An increase of pO2 in mice breathing isoflurane was demonstrated with Oxyphor and PpIX DF, indicating similar intracellular and extracellular oxygenation. These findings demonstrate the importance of routine anesthesia administration, where consistency in the timing between induction and irradiation may be crucial to minimizing variability in radiation response.

Videolaryngoscopy during Urgent Cesarean Delivery: Association with Neonatal Intensive Care Unit Admission.

Parturients are at increased risk for difficult airway management with subsequent fetal complications. Videolaryngoscopy was opined to be the new standard of airway care to facilitate orotracheal intubation under urgent care conditions. We examined in parturients requiring general anesthesia for urgent cesarean delivery the association of the type of laryngoscopy technique and time required to facilitate orotracheal intubation with the incidence of subsequent neonatal intensive care unit (NICU) admission. Following institutional review board approval, 431 parturients aged 18 years and older who underwent urgent cesarean section requiring general anesthesia were entered into this study. Patient characteristics, maternal comorbidities, and indications for urgent cesarean delivery were collected from the electronic medical records from January 2013 to November 2018. Orotracheal intubation times by type of laryngoscopy (video or direct) and NICU admission rates also were collected. A measure of effect size, risk differences with 95% confidence intervals (CIs), were calculated for the likelihood of NICU admission by difficult orotracheal intubation and by type of laryngoscopy used to secure the airway. Videolaryngoscopy as the primary type of laryngoscopy was used in 24.1% (95% CI 20.3%-28.3%) of general anesthetics. The incidence of difficult orotracheal intubation was 4.4% (95% CI 2.8%-6.7%), with a higher incidence observed with videolaryngoscopy (8.7%) than with direct laryngoscopy (3.1%) and a risk difference of 5.6% (95% CI 0.001%-11.3%). The incidence of NICU admission was 38.4% (95% CI 34.0%-43.1%). Times for successful orotracheal intubation were longer with videolaryngoscopy. Videolaryngoscopy had a higher association for NICU admission (47%) than for direct laryngoscopy (36%), with a risk difference of 11.4% (95% CI 0.01%-22.3%). Videolaryngoscopy did not decrease the incidence of difficult orotracheal intubation, and it did not decrease the time associated with orotracheal intubation. Videolaryngoscopy was associated with a higher association of NICU admission. These results suggest that videolaryngoscopy does not supplant direct laryngoscopy as the standard of care for orotracheal intubation under urgent care conditions of general anesthesia for cesarean section.

ENLIGHTED phase 3 study: Efficacy and safety of padeliporfin vascular targeted photodynamic therapy (VTP) for treatment of low-grade upper tract urothelial cancer (LG UTUC).

TPS4622 Background: Padeliporfin VTP has demonstrated safety and efficacy for UTUC treatment in a Phase 1 study (NCT03617003). Padeliporfin VTP is a combination product: a drug, padeliporfin administered IV; a device: a laser light delivery system/laser-source of light emitting near-infrared (NIR) light at 753nm; and an optic fiber delivering the light endoluminally to the vicinity of UTUC tumors within the collecting system. We report the preliminary efficacy and safety outcomes of Padeliporfin VTP for Treatment of LG UTUC in ENLIGHTED, a Phase 3 trial (NCT04620239). Methods: This is an open-label phase 3 study from USA, EU and Israel. Key inclusion criteria is up to 2 biopsy-proven LG UTUC with index tumor ≤15mm in the kidney and≤20mm in the ureter with an absence of high-grade cells on cytology. VTP is performed via retrograde upper tract endoscopy under anesthetic and low light conditions, Padeliporfin is injected IV and a laser light diffuser fiber 20-40 mm is positioned in proximity of the tumor through the scope. After Padeliporfin injection, the laser fiber is illuminated for 10 min. The fiber can be repositioned to provide up to 3 treatments within the upper tract. Patients are treated in two phases: Induction(ITP) and Maintenance Treatment Phases (MTP). ITP consists of 1-3 VTPs provided at 4-week intervals until achieving complete response (CR) or treatment failure. Patients achieving CR will proceed to the MTP and be followed with endoscopic evaluation every 3 months with VTP provided for recurrent tumors only up to 12 months. Patients with high-grade recurrences will be deemed treatment failures and removed from the study to standard of care treatment. Patients completing the MTP, will be followed for an additional 48 months for long-term outcomes. Primary outcome is CR on endoscopic evaluation and selective cytology at the time of primary response evaluation (28 ± 3 days post last treatment) during padeliporfin VTP ITP. A total of 100 patients are to be enrolled. As of 21 Jan 2024, 17 patients have been treated. 13 patients completed ITP and had CR 10/13 (77%) and PR 3/13 (23%). Patients baseline characteristics: age 67±12 years; gender: 9(53%) males and 8(47%) females; tumors location: 5(29%) in ureter, 13(76%) in the kidney; number of tumors: 7(41%) 2 tumors, 10(59%) 1 tumor. The most frequent treatment related adverse events were: flank pain 17%, vomiting 8%, fatigue 8%, nausea 6%, hematuria 6%, all Grade 1-2, resolved within few days. Grade 3 serious adverse events 9% (flank pain, hypertension, renal colic, urinary tract infection) were resolved within 2-7 days. To date Padeliporfin VTP has shown evidence of safety and efficacy with preliminary data that is consistent with prior experience. Recruitment for the ENLIGHTED trial is ongoing with results expected to provide basis for approval of a new therapy that clinically benefits pts. Clinical trial information: NCT04620239 .

Effects of Dexmedetomidine on the Recovery Quality of Donors Undergoing Pure Laparoscopic Donor Hepatectomy

To investigate the effects of intraoperative intravenous administration of dexmedetomidine (DEX) on the recovery quality of donors undergoing pure laparoscopic donor hepatectomy. A total of 56 liver donors who were going to undergo scheduled pure laparoscopic donor hepatectomy were enrolled and randomly assigned to two groups, a DEX group ( n=28) and a control group ( n=28). Donors in the DEX group received DEX infusion at a dose of 1 μg/kg over 15 minutes through a continuous pump, which was followed by DEX at 0.4 μg/(kg·h) until the disconnection of the portal branch. Donors in the control group were given an equal volume of 0.9% normal saline at the same infusion rate and over the same period of time as those of the dex infusion in the DEX group. The primary outcome was the incidence of emergence agitation (EA). The Aono's Four-point Scale (AFPS) score was used to assess EA. The secondary observation indicators included intraoperative anesthesia and surgery conditions, spontaneous respiration recovery time, recovery time, extubation time, scores for the Ramsay Sedation Scale, the incidence of chills, numeric rating scale (NRS) score for pain, and blood pressure and heart rate after extubation. The incidence of EA was 10.7% and 39.3% in the DEX group and the control group, respectively, and the incidence of EA was significantly lower in the DEX group than that in the control group ( P=0.014). The APFS scores after extubation in the DEX group were lower than those in the control group (1 [1, 1] vs. 2 [1, 3], P=0.005). Compared to the control group, the dosages of intraoperative propofol and remifentanil were significantly reduced in the DEX group ( P<0.05). During the recovery period, the number of donors requiring additional boluses of analgesia, the blood pressure, and the heart rate were all lower in the DEX group than those in the control group ( P<0.05). No significant differences between the two groups were observed in the spontaneous respiration recovery time, recovery time, extubation time, the incidence of chills, NRS score, scores for the Ramsay Sedation Scale, and the length-of-stay in postanesthesia care unit (PACU) ( P>0.05). DEX can reduce the incidence of EA after pure laparoscopic donor hepatectomy and improve the quality of recovery without prolonging postoperative recovery time or extubation time.

Multimodal monitoring using the Analgesia Nociception Index (ANI) during catheter ablation of the heart in patients with sinus rhythm and short-term induced atrial arrhythmia: prospective observational study

INTRODUCTION: Сatheter ablation (CA) is a painful procedure requiring an assessment of the balance between nociception associated with surgical trauma and anesthesia induced antinociception. OBJECTIVE: To evaluate the effectiveness of the monitoring system “ANI Monitor” for anesthesia and intensive care in patients with sinus rhythm and short-term induced (&lt; 1 min) atrial arrhythmia (STIAA). MATERIALS AND METHODS: The study group of our trial consisted of 94 patients with CA and ANI Monitor. The control group consisted of 94 patients, selected using the “copy-pair” method, with standard (hemodynamic) monitoring. A Numerical Rating Scale (NRS) was used for assessment the intensity of pain. At the stage of femoral vein catheterization in all patients regional anesthesia was performed, at the CA stage, procedural sedation and/or analgesia (PSA) was titrated with the administration of propofol and fentanyl (under the control with ANI Monitor). Statistical data processing was carried out using Statistica 10.0 and SPSS programs. RESULTS: At the stage of CA under PSA, negative correlation was found between NRS and ANIm in patients with sinus rhythm and STIAA (r = −0.37). At the threshold of 56.0 the sensitivity and specificity of ANIm in detecting NRS ˃ 3 were 60 and 100 %, respectively, corresponding to ROC curve AUC of 0.81. Significant changes in hemodynamic reactivity were not registered. It was revealed the reduction of fentanyl administration in patients of the study group (0.04 ± 0.02 and 0.05 ± 0.03 µg/kg/min, respectively, p &lt; 0.001) under the control of ANI Monitor. CONCLUSIONS: ANI Monitor during CA in patients with sinus rhythm and STIAA was more effective in detecting harmful nociceptive stimuli compared to standard (hemodynamic) monitoring. The use of ANI Monitor to control the fentanyl administration could create conditions for opioid-sparing anesthesia.

Emergence characteristics comparing endotracheal tube to reinforced laryngeal mask airway during endoscopic sinus surgery - A randomised controlled study.

During endoscopic sinus surgery, anaesthetic conditions significantly impact the intraoperative surgical field and bleeding during emergence. While the endotracheal tube (ETT) has been traditionally used in sinus surgery, a reinforced laryngeal mask airway (RLMA) that produces less upper airway stimulation may result in smoother emergence. A randomised controlled trial of 72 patients undergoing elective sinus surgery was conducted, with the allocation of airway technique to either ETT with a throat pack or RLMA. The primary outcome measure was emergence time, measured by time to opening eyes on commands at the cessation of anaesthesia, and the secondary outcomes were time to removal of airway device, remifentanil use, procedure times, mean arterial pressure (MAP) and the RLMA grade of blood contamination. The continuous variables were analysed using Student's t-tests and discrete variables, count tables were analysed using Fisher's exact tests. There was no significant difference in the emergence time between the ETT and RLMA groups (P = 0.83). Remifentanil use was significantly higher in the ETT group than in the RLMA group (P = 0.022). The ETT group showed a significantly increased total anaesthetic time (P = 0.01). MAP was not significant during preinduction, maintenance or post-RMLA removal. The highest grade of contamination was grade 2 in RLMA. RLMA had lower rates of postoperative adverse events. RLMA comparable to ETT in terms of emergence time. The RMLA group had lower remifentanil use, anaesthesia duration and fewer postoperative adverse events such as cough and throat pain.

Comparative assessment of hemodynamic parameters during anesthesia in orthopedic and traumatological operations on the lower extremities in children

Objective. To conduct a comparative analysis of hemodynamic parameters during orthopedic and traumatological operations on the lower extremities in children performed under conditions of multicomponent balanced general and combined anesthesia. Materials and methods. A single-center prospective study. The present study included 60 children aged 6 to 17 years who underwent planned orthopedic and trauma surgery interventions on the lower extremities. Patients were divided into two groups depending on the method of anesthesia: Group 1 (n = 25) - multicomponent balanced general anesthesia, Group 2 (n = 35) - combined anesthesia (multicomponent balanced general anesthesia in combination with regional blocks of the sciatic and femoral nerves). To solve these problems, a comparative analysis of heart rate, systolic, diastolic and mean arterial blood pressure was carried out at seven stages of the study: 1st stage - initial, child on the operating table; 2nd stage - induction of anesthesia; 3rd stage - placement of the laryngeal mask; 4th stage - start of the operation; 5th stage - traumatic stage of the operation; 6th stage - completion of the operation; 7th stage - after removal of the laryngeal mask. Results. In all cases, the surgical interventions were successful. The study found that in the group of children who underwent multicomponent general anesthesia at the 4th (start of surgery), 5th (traumatic stage of surgery) and 6th (end of surgery) stages, heart rate (HR) was higher compared to the group of combined anesthesia. Systolic and mean arterial blood pressure during the traumatic phase of surgery were also higher in children undergoing multicomponent general anesthesia. The values of diastolic blood pressure did not differ between groups throughout the study with the exception of the 3rd stage (laryngeal mask placement) where lower values were observed in patients of the Group 1. Diastolic blood pressure values did not differ between groups throughout the study, with the exception of 3th stage (laryngeal mask placement), where lower values were noted in Group 1 patients. Conclusion. Combined methods of anesthesia based on the combination of multicomponent general anesthesia and conductive peripheral nerve blocks provide the greatest hemodynamic stability during orthopedic and traumatologic surgeries on the lower extremities in children.

Anesthetic Oxygen Use and Sex Are Critical Factors in the FLASH Sparing Effect

IntroductionUltra-high dose-rate (UHDR) radiation has been reported to spare normal tissue compared to conventional dose-rate (CDR) radiation. However, important work remains to be done to improve the reproducibility of the FLASH effect. A better understanding of the biological factors that modulate the FLASH effect may shed light on the mechanism of FLASH sparing. Here, we evaluate whether sex and/or use of 100% oxygen as carrier gas during irradiation contribute to the variability of the FLASH effect. MethodsC57BL/6 mice (24 male, 24 female) were anesthetized using isoflurane mixed with either room air or 100% oxygen. Subsequently, the mice received 27 Gy of either 9 MeV electron UHDR or CDR to a 1.6 cm2 diameter area of the right leg skin using the Mobetron linear accelerator. The primary post-radiation endpoint was time to full thickness skin ulceration. In a separate cohort of mice (4 male, 4 female) skin oxygenation was measured using PdG4 Oxyphor under identical anesthesia conditions. ResultsIn the UHDR group, time to ulceration was significantly shorter in mice that received 100% oxygen compared to room air, and amongst them female mice ulcerated sooner compared to males. However, no significant difference was observed between male and female UHDR mice that received room air. Oxygen measurements showed significantly higher tissue oxygenation using 100% oxygen as the anesthesia carrier gas compared to room air, and female mice showed higher levels of tissue oxygenation compared to males under 100% oxygen. ConclusionThe FLASH sparing effect is significantly reduced using oxygen during anesthesia compared to room air. The FLASH sparing was significantly lower in female mice compared to males. Both tissue oxygenation and sex are likely sources of variability in UHDR studies. These results suggest an oxygen-based mechanism for FLASH, as well as a key role for sex in the FLASH skin sparing effect.

Measuring spatial visual loss in rats by retinotopic mapping of the superior colliculus using a novel multi-electrode array technique

BackgroundThe retinotopic map property of the superior colliculus (SC) is a reliable indicator of visual functional changes in rodents. Electrophysiological mapping of the SC using a single electrode has been employed for measuring visual function in rat and mouse disease models. Single electrode mapping is highly laborious requiring long-term exposure to the SC surface and prolonged anesthetic conditions that can adversely affect the mapping data. New methodTo avoid the above-mentioned issues, we fabricated a fifty-six (56) electrode multi-electrode array (MEA) for rapid and reliable visual functional mapping of the SC. Since SC is a dome-shaped structure, the array was made of electrodes with dissimilar tip lengths to enable simultaneous and uniform penetration of the SC. ResultsSC mapping using the new MEA was conducted in retinal degenerate (RD) Royal College of Surgeons (RCS) rats and rats with focal retinal damage induced by green diode laser. For SC mapping, the MEA was advanced into the SC surface and the visual activities were recorded during full-filed light stimulation of the eye. Based on the morphological examination, the MEA electrodes covered most of the exposed SC area and penetrated the SC surface at a relatively uniform depth. MEA mapping in RCS rats (n=9) demonstrated progressive development of a scotoma in the SC that corresponded to the degree of photoreceptor loss. MEA mapping in the laser damaged rats demonstrated the presence of a scotoma in the SC area that corresponded to the location of retinal laser injury. Comparison with existing methods and conclusionsThe use of MEA for SC mapping is advantageous over single electrode recording by enabling faster recordings and reducing anesthesia time. This study establishes the feasibility of the MEA technique for rapid and efficient SC mapping, particularly advantageous for evaluating therapeutic effects in retinal degenerate rat disease models.

Is ureteroscopy and active stone treatment safe and effective in octogenarians? A review of current literature.

With the aging of our patient population, and the increasing incidence of kidney stone disease in the elderly, active stone treatment is becoming more common. In this review of current literature, we aim to assess safety and efficacy of ureteroscopy (URS) as primary treatment for urolithiasis in the octogenarians. A scoping review of literature according to the PRISMA guidelines was performed, using the relevant search terms. Original articles were screened and included. A narrative review of the studies is provided, with emphasis on outcomes of URS in the elderly. 10 studies were included in the analysis. URS performed in the elderly population showed a good safety and efficacy, with stone-free rates (SFR) comparable to the general population. URS specific complication rates seems to be comparable to the other age groups, with postoperative events mostly related to anaesthesia and pre-existing medical conditions. The overall complication rate was still low, with a slightly prolonged hospital stay. Predictors for SFR were age, severe comorbidities and stone burden. URS for stone treatment in the elderly population is safe and effective, with comparable surgical outcomes to that of the general population. As comorbidities play an important role in the fitness for surgery and overall survival, risks and benefit of active stone treatment should be carefully balanced in this group.

Comparative effects of intravenous esmolol and lidocaine on bispectral index during propofol-fentanyl induction in patients scheduled for elective surgeries under general anaesthesia

INTRODUCTION: Laryngoscopy and endotracheal intubation at induction of anaesthesia have been associated with awareness and haemodynamic fluctuations. Agents that can mitigate these effects should create better anaesthetic conditions. This study aimed to compare the effects of intravenous esmolol and lidocaine on the bispectral index (BIS) and haemodynamic responses during induction of general anaesthesia with propofol/fentanyl in adult patients scheduled for elective surgical procedures.&#x0D; METHODS: This was a prospective randomized controlled study in ninety patients aged 18-65 years who were randomized into three groups to receive either IV esmolol 0.5 mg/kg, IV lidocaine 1.5 mg/kg or normal saline prior to induction of general anaesthesia.&#x0D; RESULTS: The esmolol group had a significantly shorter induction time (p&lt;0.0001) and a lower dose of propofol consumed (p&lt;0.0001) than the lidocaine group. The mean pulse rate was significantly lower at the 1st min to 4th min post-intubation in esmolol and lidocaine groups compared to the control group (p values; 1 min= 0.005, 2 min= 0.008, 3 min= 0.023, 4 min= 0.018). There was a significant difference in the systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) in the three groups at 2 min post-intubation.&#x0D; CONCLUSION: Pre-induction intravenous esmolol 0.5 mg/kg was more effective than intravenous lidocaine 1.5 mg/kg in reducing the induction dose of propofol and the induction time. Esmolol also prevented increases in BIS better than lidocaine following endotracheal intubation but both agents were equally effective in attenuating the haemodynamic changes associated with laryngoscopy and endotracheal intubation.