Depth Of Anesthesia Research Articles

Clinical evaluation of bispectral index‐guided closed‐loop infusion of propofol for preschool children: A multi‐center randomized controlled study

ABSTRACTImportanceThe closed‐loop infusion system can automatically adjust and maintain the depth of anesthesia by using the propofol target‐controlled infusion (TCI) model under the feedback guidance of the bispectral index (BIS).ObjectiveTo evaluate the safety and superiority of closed‐loop TCI of propofol guided by BIS during maintenance of generalized intravenous anesthesia for preschool children.MethodsA total of 120 children aged 1–6 years were enrolled and were divided into a closed‐loop feedback group (Group C) and an open‐loop manual control group (Group O), with 60 participants in each group. For anesthesia maintenance, the propofol infusion rate was adjusted by the injection system under the guidance of BIS in Group C and was manually adjusted by anesthesiologists according to the BIS and clinical experience in Group O, to maintain a BIS level of 50. The time ratio of adequate anesthesia (40 ≤ BIS ≤ 60), light anesthesia (BIS > 60), and deep anesthesia (BIS < 40) were recorded.ResultsA total of 119 patients (59 in Group C and 60 in Group O) were enrolled in the study. Group C demonstrated a higher time ratio of adequate anesthesia (P = 0.014) compared to Group O. The time ratio of light anesthesia and the global score was lower in Group C than in Group O (P = 0.010, P = 0.015, respectively). The frequency of adjustment per unit of time was higher in Group C for propofol (P < 0.001), while it was lower for remifentanil (P = 0.010).InterpretationBIS‐guided closed‐loop infusion of propofol is safe and effective for preschool children. The depth of anesthesia is controlled more accurately and smoothly.

Effect of classical music on light-plane anaesthesia and analgesia in dogs subjected to surgical nociceptive stimuli

The objectives of this prospective, randomized, blinded, crossover, experimental study were to detect the potential anaesthetic- and analgesic-sparing effects of classical music provided to dogs undergoing skin surgery, and to investigate the role of substance P as an intraoperative pain indicator. Twenty dogs were included, each subjected to three different treatments: Chopin music, Mozart music and no music. They were premedicated with acepromazine, butorphanol and meloxicam and anaesthetized with propofol and isoflurane. Fentanyl was used as rescue analgesia. The anaesthetic depth was monitored by using the bispectral index along with standard anaesthetic monitoring, and autonomic nervous system responses were used to monitor the adequacy of analgesia. Furthermore, measurements of substance P serum concentration were carried out. Dogs exposed to music required less isoflurane and fentanyl. Furthermore, a statistically significant effect of time on substance P concentration was observed regardless of exposure to music, and there was a significant interaction effect between different timepoints and the type of acoustic stimulus. Classical music seems to have an isoflurane and fentanyl sparing effect on dogs undergoing minor surgery. Following surgical stimulation, the serum substance P concentration increases rapidly, and thus appears to be a potentially useful pain indicator.

Assessment of the depth of anesthesia with hidden Markov model based on cardiopulmonary variables

Assessment of the depth of anesthesia with hidden Markov model based on cardiopulmonary variables

SEDATION AND LARYNGOSPASM IN PEDIATRIC SURGERY

Introduction: The use of anesthetics in pediatrics is essential for diagnostic and therapeutic procedures. The incidence of post-anesthetic respiratory complications is often avoidable with appropriate intervention. Laryngospasm, a reflex obstruction of the vocal cords, is more common in children. Objective: To discuss respiratory complications, with an emphasis on laryngospasm, during the use of anesthetics in pediatric procedures. Method: The Medical Literature Analysis and Retrieval System Online (MEDLINE, via PUBMED), Latin American and Caribbean Health Sciences Literature (LILACS), Scientific Electronic Library Online (SciELO), and Virtual Health Library (VHL) databases were used. Seven articles were selected that met the systematic review criteria. Results: The incidence of laryngospasm is 0.87% in adults, 1.7% in children, and 2.82% in babies. In children, it occurs mainly during emergence from anesthesia. Risk factors include inadequate anesthesia, respiratory infections and multiple attempts at airway management. Drug combinations such as propofol, ketamine and fentanyl are used to minimize complications. Preventive measures include clearing secretions and adequate depth of anesthesia. Drugs such β2-adrenergic agonists, such as albuterol, are used to reduce respiratory resistance during intubation. Training strategies with low-cost simulators are effective for managing difficult airways in pediatrics. In pediatric surgery, the laryngeal mask is preferred to endotracheal intubation to reduce respiratory complications. Studies indicate that positive communication between anesthesia teams improves performance in critical situations. Conclusion: Laryngospasm is a serious complication in pediatric anesthesia, more common in children due to their anatomy and sensitive reflexes. Risk factors include respiratory infections, asthma, smoking, gastroesophageal reflux, and superficial anesthesia. Prevention involves the proper use of anesthetics, cleaning secretions and careful monitoring. Medications such as propofol, ketamine, and albuterol can reduce adverse effects. Simulator training and effective communication in anesthesia teams improve clinical performance. With proper management, most episodes are resolved without long-term complications.

Chaotic nature of the electroencephalogram during shallow and deep anesthesia: From analysis of the Lyapunov exponent

In conscious states, the electrodynamics of the cortex are reported to work near a critical point or phase transition of chaotic dynamics, known as the edge-of-chaos, representing a boundary between stability and chaos. Transitions away from this boundary disrupt cortical information processing and induce a loss of consciousness. The entropy of the electroencephalogram (EEG) is known to decrease as the level of anesthesia deepens. However, whether the chaotic dynamics of electroencephalographic activity shift from this boundary to the side of stability or the side of chaotic enhancement during anesthesia-induced loss of consciousness remains poorly understood. We investigated the chaotic properties of EEGs at two different depths of clinical anesthesia using the maximum Lyapunov exponent, which is mathematically regarded as a formal measure of chaotic nature, using the Rosenstein algorithm. In 14 adult patients, 12 s of electroencephalographic signals were selected during two depths of clinical anesthesia (sevoflurane concentration 2% as relatively deep anesthesia, sevoflurane concentration 0.6% as relatively shallow anesthesia). Lyapunov exponents, correlation dimensions and approximate entropy were calculated from these electroencephalographic signals. As a result, maximum Lyapunov exponent was generally positive during sevoflurane anesthesia, and both maximum Lyapunov exponents and correlation dimensions were significantly greater during deep anesthesia than during shallow anesthesia despite reductions in approximate entropy. The chaotic nature of the EEG might be increased at clinically deeper inhalational anesthesia, despite the decrease in randomness as reflected in the decreased entropy, suggesting a shift to the side of chaotic enhancement under anesthesia.

Bispectral Index Monitoring Effect on Delirium Occurrence and Nursing Quality Improvement in Post-anesthesia Care Unit Patients Recovering From General Anesthesia: A Randomized Controlled Trial.

The effect of intraoperative anesthesia depth monitoring on deliriumoccurrenceand improvement of nursing quality in the post-anesthesia care unit (PACU) remains unclear.We aimed to explore the effect of intraoperative anesthesia bispectral index (BIS) monitoring on delirium occurrence and improvement of nursing quality in the PACU for patients recovering from general anesthesia. This randomized controlled trial included 120 patients, aged 20-80 years, classified as grades I-III according to the American Society of Anesthesiologists. The BIS-guided group (group B) underwent intraoperative monitoring of BIS anesthesia depth (maintained within the anesthetic range (40-60)).The depth of anesthesia was not monitored in the non-BIS-guided group (group C). The patient's vital signs were recorded at the beginning of the operation (T0), upon entering the PACU (T1), 15 min after extubation (T2), and after leaving the PACU (T3). Delirium score, emergence period (extubation and PACU observation times), and adverse events in the PACU were monitored. The nursing activity score (NAS) was used to evaluate the quality of care. Group B exhibited significantly lower heart rate and mean arterial pressure at T1 and T2, shorter time to extubation and PACU observation time, and a significantly lower incidence of adverse events than group C. Group B had significantly lower Ricker sedation-agitation scores and a lower incidence of delirium than group C.The NAS was significantly lower for group B than for group C. Patients aged 60-80 years in group C experienced agitation, requiring 30% more frequent assistance from one or two nurses than those in group B. Intraoperative BIS monitoring can reduce the incidence of adverse events in the PACU, diminish the incidence of delirium during the recovery period in elderly patients, lessen the nursing workload, improve nursing quality, and promote patient rehabilitation, thus meriting clinical application.

Burst-Suppression EEG Reactivity to Photic Stimulation-A Translational Biomarker in Hypoxic-Ischemic Brain Injury.

The reactivity of an electroencephalogram (EEG) to external stimuli is impaired in comatose patients showing burst-suppression (BS) patterns following hypoxic-ischemic brain injury (HIBI). We explored the reactivity of BS induced by isoflurane in rat models of HIBI and controls using intermittent photic stimulation (IPS) delivered to one eye. The relative time spent in suppression referred to as the suppression ratio (SR) was measured on the contralateral fronto-occipital cortical EEG channel. The BS reactivity (BSR) was defined as the decrease in the SR during IPS from the baseline before stimulation (SRPRE). We found that BSR increased with SRPRE. To standardize by anesthetic depth, we derived the BSR index (BSRi) as BSR divided by SRPRE. We found that the BSRi was decreased at 3 days after transient global cerebral ischemia in rats, which is a model of brain injury after cardiac arrest. The BSRi was also reduced 2 months after experimental perinatal asphyxia in rats, a model of birth asphyxia, which is a frequent neonatal complication in humans. Furthermore, Oxytocin attenuated BSRi impairment, consistent with a neuroprotective effect in this model. Our data suggest that the BSRi is a promising translational marker in HIBI which should be considered in future neuroprotection studies.

Comparing the efficacy of adrenaline, clonidine, and dexmedetomidine in enhancing local anesthesia for impacted third molar extraction: a randomized controlled trial.

In human dentition, the most commonly impacted teeth are the mandibular third molars (M3M). The removal or extraction of these teeth often causes anxiety in patients due to the perceived pain involved in the process. Therefore, pain must be effectively managed using anesthesia. The use of newer local anesthetic drugs can help minimize side effects and drug interactions. Traditionally, adrenaline is used as a vasoconstrictor along with lignocaine. When combined with lignocaine, the alpha agonists dexmedetomidine and clonidine can extend the duration of anesthesia, thereby reducing the need for additional pain-relieving medications. This study used a randomized, triple-blind, parallel-arm design. Sixty patients were screened, and 45 systemically healthy patients requiring unilateral surgical removal of impacted mandibular third molars with similar difficulty (moderate-to-difficult according to the Modified Pederson's Index) were included in the study. Patients were allocated into three groups as follows: Group A: 2% Lignocaine Hydrochloride with 1:100,000 Adrenaline, Group C: 2% Lignocaine Hydrochloride with 15 µg/mL Clonidine, and Group D: 2% Lignocaine Hydrochloride with 1 µg/mL Dexmedetomidine. The evaluated parameters were the time of onset of anesthesia, depth of anesthesia, hemodynamic parameters, and duration of postoperative analgesia. Group D had a faster onset of action and prolonged duration of postoperative analgesia compared with Groups A and C. No statistically significant differences were observed between the three groups in terms of the depth of anesthesia and hemodynamic parameters. Group D exhibited a significantly more rapid onset of anesthesia than Groups A and C, and the postoperative analgesic effect in Group D was significantly prolonged (7.22 hours) compared with that in Groups A (4.54 hours) and C (2.1 hours). Patients receiving the Group D solution experienced an extended period of comfort without the need for analgesics for up to 7.22 hours post-procedure.

SQI-DOANet: electroencephalogram-based deep neural network for estimating signal quality index and depth of anaesthesia.


Monitoring the depth of anaesthesia (DOA) during surgery is of critical importance. However, accurate and real-time estimation of DOA remains a challenging task. In this paper, we proposed a signal quality index (SQI) network (SQINet) for assessing the electroencephalogram (EEG) signal quality and a DOA network (DOANet) for analyzing EEG signals to precisely estimate DOA. The two networks are termed SQI-DOANet.
Approach:
The SQINet contained a shallow convolutional neural network to quickly determine the quality of the EEG signal. The DOANet comprised a feature extraction module for extracting features, a dual attention module for fusing multi-channel and multi-scale information, and a gated multilayer perceptron module for extracting temporal information. The performance of the SQI-DOANet model was validated by training and testing the model on the large VitalDB database, with the bispectral index (BIS) as the reference standard.
Main results:
The proposed DOANet yielded a Pearson correlation coefficient with the BIS score of 0.88 in the 5-fold cross-validation, with a mean absolute error (MAE) of 4.81. The mean Pearson correlation coefficient of SQI-DOANet with the BIS score in the 5-fold cross-validation was 0.82, with an MAE of 5.66.
Significance:
The SQI-DOANet model outperformed three compared methods. The proposed SQI-DOANet may be used as a new deep learning method for DOA estimation. The code of the SQI-DOANet will be made available publicly at https://github.com/YuRui8879/SQI-DOANet.&#xD.

Comparative analysis of the consistency of anesthesia depth between anesthesia index and Narcotrend index in monitoring pediatric tonsillectomy/adenoidectomy surgery

Objective: To analyze the consistency of the anesthesia index (AI) and Narcotrend index (NI) in monitoring the depth of anesthesia in pediatric tonsil/adenoidectomy. Methods: A total of 129 children who underwent elective tonsil/adenoidectomy at Xijing Hospital Affiliated to Air Force Medical University from July 2022 to October 2023 were prospectively enrolled. Both AI monitoring by ConView monitor and NI monitoring by Narcotrend monitor were conducted for children after they were admitted to the operating room, while Propofol-remifentanil combined with total intravenous anesthesia was used during the operation and the anesthetic dose was adjusted to maintain the NI value at 40-60. In addition, the AI and NI values were recorded at following time points: quiet eyes closing (T1), the beginning of induction (T2), loss of consciousness (T3), tracheal intubation (T4), the beginning of surgery (T5), during tonsil excision (T6), adenoidectomy (T7), the end of surgery (T8), consciousness recovery (T9) and tracheal extubation (T10). Bland-Altman consistency analysis was used to evaluate the consistency of the results of the two types of anesthesia depth monitoring, AI value and NI value. Receiver operator characteristic (ROC) curve and area under curve (AUC) were used to analyze the predictive efficacy of AI and NI values for the state of consciousness of children. The intraoperative awareness was followed up at 24 hours, 1 week and 1 month after surgery. Results: In 129 cases, there were 78 boys and 51 girls, with an average age of (7.2±3.2) years and an operation time of (72.8±14.0) min. No AI data were missing, but 13 NI data were missing, with a missing rate of 10.1% (13/129). At time points T1-T10, the AI values were 67.5±19.2 and the NI values were 67.2±19.2. Bland-Altman consistency analysis showed that the difference in value between AI and NI was 0.3 (95%CI:-0.1-0.6, P=0.120), with an out-of-consistency range of 4.0% (51/1 290). Before anesthesia induction, AI and NI values were maintained at a high level; with the beginning of anesthesia induction and the disappearance of the children's consciousness, both AI and NI values gradually decreased; after discontinuing the infusion of anesthetics, the values of AI and NI gradually increased, and the change trend of AI and NI in each stage of the perioperative period was consistent, and there was no significant difference between the two groups at each time point (all P>0.05). ROC curve analysis showed that the cut-off value for predicting the state of consciousness using AI was 72.5, with an AUC of 0.73 (95%CI: 0.70-0.75), and the cut-off value of NI was 79.5 and the AUC was 0.74 (95%CI: 0.72-0.77). There was no significant difference in AUC between the two indices (P=0.310). None of the children had intraoperative awareness. Conclusion: Both AI and NI can be used to monitor the depth of anesthesia in pediatric tonsil/adenoidectomy with high accuracy.

The role of depth of general anesthesia in serum CGRP and SP level in diabetes patients.

Diabetes, which is associated with cardiovascular disease and related microvascular complications, affects life expectancy and decrease quality of life. A trial reports that the risk of patients with diabetes having cardiovascular disease is 2-4 times compared with that in patients without diabetes. This study aims to investigate the relationship between depth of general anesthesia in patients with diabetes mellitus. This clinical study totally includes 40 patients with diabetes mellitus, and these patients are divided into following two groups: diabetes mellitus deep anesthesia group and diabetes mellitus light anesthesia group, and then these patients receive general anesthesia combined with laparoscopic surgery. Preoperative patient general data and intraoperative patient general data are collected and analyzed. Calcitonin gene-related peptide (CGRP) and substance P (SP) level are determined by Enzyme-linked immunosorbent assay (ELISA). This study included a total of 40 patients. There were no significant differences in demographic and preoperative patient general data between the two groups. Measurements were taken for operative time, anesthesia time, recovery time after drug withdrawal, dwell time in the recovery room, intraoperative fluid volume, intraoperative blood loss, and intraoperative urine output between the two groups. Significant differences were observed in the recovery time after drug withdrawal between the two groups. CGRP and SP level in diabetes mellitus deep anesthesia group are evidently more than those in diabetes mellitus light anesthesia group. CGRP and SP level are involved in the diabetes mellitus and up-regulated CGRP and SP can prevent the development of diabetes mellitus. Our study extends the existing literature by addressing a gap in knowledge regarding the impact of anesthesia depth on neuropeptide levels in diabetes mellitus patients. By delineating this relationship, we aim to contribute to the advancement of perioperative care practices and ultimately improve outcomes for individuals with diabetes undergoing surgical procedures. Our study's findings provide valuable insights into the complex interactions between anesthesia, neuropeptides, and diabetes mellitus, offering the potential for personalized perioperative care, enhanced pain management, and improved surgical outcomes. These implications highlight the clinical relevance of our research and its potential to inform future advancements in perioperative care for diabetic patients undergoing surgery.

Comparison of sevoflurane and propofol in combination with remifentanil on the quality of postoperative recovery in patients undergoing laparoscopic bariatric surgery.

This study aimed to evaluate and compare the effects of sevoflurane + remifentanil (Sev + Rem) and propofol + remifentanil (Pro + Rem) on the postoperative recovery quality of patients undergoing laparoscopic bariatric surgery to determine which anesthesia regimen provides a better overall recovery experience. Sixty patients were divided into two groups based on the treatments they underwent: Sev + Rem (n = 30) and Pro + Rem (n = 30). The Sev + Rem group received sevoflurane inhalation (0.5%, increasing to 0.5-4%) and remifentanil via target-controlled infusion. The Pro + Rem group received propofol [4-8 mg/(kg·h)] and remifentanil via target-controlled infusion. Anesthesia depth was maintained at a bispectral index of 40-60 in both groups. Perioperative data, hemodynamic parameters, and postoperative recovery quality were assessed. Compared to the Pro + Rem group, the dose of remifentanil in the Sev + Rem group was significantly lower (1693.67 ± 331.75 vs. 2,959 ± 359.77, p < 0.001), the proportion of patients used norepinephrine was markedly higher [16 (53.33) vs. 8 (26.67), p = 0.035], and the time of extubation was earlier (356.33 ± 63.17 vs. 400.3 ± 50.11, p = 0.004). The Hemodynamic results showed the HR in the Sev + Rem group was faster than that in the Pro + Rem group at the beginning of surgery and 1 h post-surgery (67.37 ± 4.40 vs. 64.33 ± 4.44, p = 0.010, 69.07 ± 4.23 vs. 66.40 ± 5.03, p = 0.030). In regard to the assessment of postoperative recovery quality, the emotional state scores in the Sev + Rem group were significantly lower than the Pro + Rem group (36.83 ± 2.79 vs. 39.50 ± 4.64, p = 0.009). The two anesthesia modalities (Sev + Rem and Pro + Rem) have their advantages and disadvantages for patients undergoing laparoscopic bariatric surgery and have comparable effects on postoperative recovery quality.

Measure of the prediction capability of EEG features for depth of anesthesia in pigs

Measure of the prediction capability of EEG features for depth of anesthesia in pigs

Bispectral Index Monitoring and Combinations in Anesthesia Safety

Anesthesia should ideally provide an adequate level of hypnosis (sleep, unawareness/non-recall), analgesia and a suitable environment for surgery (immobility, muscle relaxation). Monitoring of the depth of anesthesia is recommended to reduce awareness during anesthesia and to improve the administration of anesthetic drugs. The bispectral index (BIS) is a numerical scale based on the analysis of EEG parameters and can reduce the adverse effects associated with over- or under-dosing of anesthetic drugs. BIS is the most studied and best documented method of cerebral monitoring This summary is based on selected literature on BIS monitoring and its combination with other monitoring modalities over the last 20 years.

Dexmedetomidine as a total intravenous anesthetic in pediatric patients undergoing cleft lip and palate surgery: a case series

BackgroundSurgery for pediatric cleft lip and palate repair often utilizes high-dose opioids and inhaled anesthesia, thereby causing postoperative complications such as desaturation and/or severe agitation after anesthesia. These complications are detrimental to the child and medical personnel and cause tremendous psychologic stress to parents. Our aim is to decrease these complications through dexmedetomidine, an alpha-2 receptor agonist with anxiolytic, sympatholytic, and analgetic properties. Devoid of respiratory depressant effect, it allows patients to maintain effective ventilation and reduce agitation, postoperatively. Its unique anesthetic property may shed light on providing safe anesthesia and gentle emergence to this young, vulnerable population.Case presentationA total of 21 patients of Sundanese ethnicity, aged 3 months to 8 years (9 males and 12 females), underwent cleft lip or cleft palate surgery using total intravenous dexmedetomidine. Anesthesia was induced using sevoflurane, fentanyl, and propofol, and airway was secured. Intravenous dexmedetomidine 1.5 μg/kg was administered within 10 minutes, and a maintenance dose of 1.5 μg/kg/hour was continued as the sole anesthetic maintenance agent thereafter. Hemodynamics and anesthetic depth using Patient State Index (SEDLine™ monitor, Masimo Corporation, Irvine, CA, USA) were monitored carefully throughout the surgical procedure. Dexmedetomidine did not cause any hemodynamic derangements or postoperative complications in any of our patients. We found agitation in 9.5% (2/21) of patients.ConclusionDexmedetomidine can be used as a total intravenous anesthetic agent to maintain anesthesia and provide gentle emergence to infants and young children undergoing cleft lip and palate repair.

Substantia Innominata Glutamatergic Neurons Modulate Sevoflurane Anesthesia in Male Mice.

Accumulated evidence suggests that brain regions that promote wakefulness also facilitate emergence from general anesthesia (GA). Glutamatergic neurons in the substantia innominata (SI) regulate motivation-related aversive, depressive, and aggressive behaviors relying on heightened arousal. Here, we hypothesize that glutamatergic neurons in the SI are also involved in the regulation of the effects of sevoflurane anesthesia. With a combination of fiber photometry, chemogenetic and optogenetic tools, behavioral tests, and cortical electroencephalogram recordings, we investigated whether and how SI glutamatergic neurons and their projections to the lateral hypothalamus (LH) regulate sevoflurane anesthesia in adult male mice. Population activity of glutamatergic neurons in the SI gradually decreased upon sevoflurane-induced loss of consciousness (LOC) and slowly returned as soon as inhalation of sevoflurane discontinued before recovery of consciousness (ROC). Chemogenetic activation of SI glutamatergic neurons dampened the animals' sensitivity to sevoflurane exposure, prolonged induction time (mean ± standard deviation [SD]; 389 ± 67 seconds vs 458 ± 53 seconds; P = .047), and shortened emergence time (305 seconds, 95% confidence interval [CI], 242-369 seconds vs 207 seconds, 95% CI, 135-279 seconds; P = .004), whereas chemogenetic inhibition of these neurons facilitated sevoflurane anesthesia. Furthermore, optogenetic activation of SI glutamatergic neurons and their terminals in LH induced cortical activation and behavioral emergence from different depths of sevoflurane anesthesia. Our study shows that SI glutamatergic neuronal activity facilitates emergence from sevoflurane anesthesia and provides evidence for the involvement of the SI-LH glutamatergic pathway in the regulation of consciousness during GA.

The effect of BIS-guided anaesthesia on the incidence of postoperative nausea and vomiting in children: a prospective randomized double-blind study

BackgroundPostoperative nausea and vomiting (PONV) is a significant problem following paediatric surgery, and volatile anaesthetics are an important cause of this phenomenon. BIS-guided anaesthesia, by reducing the consumption of anaesthetics, leads to a decrease in PONV in adult patients.Study objectiveEvaluate the role of BIS-guided anaesthesia in reducing the incidence of paediatric PONV.DesignProspective, randomized, double-blind study.SettingA single center study in university hospital in Czech republic, from June 2021 to November 2022.PatientsA total of 163 children, aged 3–8 years with ASA I-II who underwent endoscopic adenoidectomy under general anaesthesia were included.InterventionsIn the intervention group, the depth of anaesthesia was maintained to values between 40 and 60 of BIS.Main outcome measureThe primary outcome was the incidence of postoperative nausea and vomiting during 24 h after surgery.ResultsThe use of BIS-guided anaesthesia led to a significant decrease in the incidence of nausea and vomiting compared to the control group [17% vs. 53%; RR (95%CI) 0.48 (0.27–0.86); p < 0.001and 16% vs. 34%; RR (95%CI) 0.33 (0.20–0.54); p = 0.01, respectively].ConclusionsBIS-guided anaesthesia decreases the incidence of postoperative nausea and vomiting in children undergoing adenoidectomy.Trial registrationClinicaltrials.gov identifier: NCT04466579.

National survey on perioperative cognitive dysfunction

BackgroundPerioperative cognitive dysfunction (PCD) is a very prevalent clinical syndrome due to the progressive aging of the surgical population.The aim of our study is to evaluate the clinical practice of Spanish anesthesiologists surveyed regarding this entity. Material and methodsProspective online survey conducted by the Neurosciences Section and distributed by SEDAR. Results544 responses were obtained, with a participation rate of 17%. 54.4% of respondents never make a preoperative assessment of cognitive impairment, only 7.5% always do it. 79.6% lack an intraoperative management protocol for the patient at risk of PCD. In the anesthetic planning, only 23.3% of the patients was kept in mind. Eighty-nine percent considered regional anesthesia with or without sedation preferable to general anesthesia for the prevention of PCD. 88.8% considered benzodiazepines to present a high risk of PCD. 71.7% considered that anesthetic depth monitoring could prevent postoperative cognitive deficit. Routine evaluation of postoperative delirium is low, only 14%. More than 80% recognize that PCD is underdiagnosed. ConclusionsAmong Spanish anesthesiologists surveyed, PCD is still a little known and underappreciated entity. It is necessary to raise awareness of the need to detect risk factors for PCD, as well as postoperative assessment and diagnosis. Therefore, the development of guidelines and protocols and the implementation of continuing education programs in which anesthesiologists should be key members of multidisciplinary teams in charge of perioperative care are suggested.

Effect of Atracurium and Rocuronium on the State and Response Entropy during Isoflurane Anesthesia: Randomized Prospective Study

Abstract Background Several researches have inspected the impact of inhalation anesthetics, intravenous anesthetics, and muscle relaxants on spectral entropy, but many didn’t evaluate the extent of neuromuscular block. Besides, they didn’t inspect the impact of distinct degrees of neuromuscular blockade on spectral entropy under dissimilar saturations of isoflurane inhalation. Hence, this study evaluated variant degrees of minimum alveolar concentration (MAC) to estimate the isoflurane concentration, along with various level of neuromuscular blockade. Aim of this study is to evaluate the effect of muscle relaxants (atracurium and rocuronium) on entropy readings (state, response entropy and response- state difference) during isoflurane anesthesia. This is a prospective randomized study where forty patients were included and divided into two study groups; patients in Group A received atracurium, while patients in Group R received rocuronium. State and response entropy were observed under MAC 0.8% and 1% under 50% and 100% neuromuscular blockage. Results There was a positive correlation between state (SE) and response entropy (RE) at baseline, different MAC, and different train of four (TOF) for both atracurium and rocuronium. State and response entropy decreased with increasing MAC of isoflurane (p &amp;lt; 0.001), while atracurium and rocuronium at TOF 50% and 100% showed no effect on SE or RE or RE-SE (P &amp;gt; 0.05). Conclusions State and response entropy can be used effectively to evaluate depth of anesthesia at different isoflurane MAC and atracurium or rocuronium doses. Registration number: ClinicalTrials.gov Identifier: NCT 05097508, Registered 5 October 2021 - prospectively registered, http://www.ClinicalTrial.gov

Comparative clinical study of attenuation of hemodynamic response to laryngoscopy and endotracheal intubation using clinical assessment guidance versus neuromuscular block monitoring guidance

Background: The hemodynamic response to the stress of laryngoscopy and endotracheal intubation does not present a problem for most patients, except in cardiovascular or cerebral disease. Various anesthetic techniques and drugs are available to control the hemodynamic response to laryngoscopy and intubation. However administration of an additional drug may adversely affect hemodynamics of the patient or unnecessarily increase the depth of anesthesia. Hence a non pharmacological measure to reduce response is preferred. The purpose of this study was to compare the hemodynamic response during laryngoscopy and intubation when choice of the moment of intubation is directed by either clinical assessment and neuromuscular monitoring with train of four. Methods: A total of 60 patients were randomised into two groups. In Group M endotracheal intubation was done after train of four count became zero in adductor pollicis muscle. In Group C timing of intubation was determined clinically by assessment of jaw muscle relaxation. Changes in heart rate (HR), systolic BP (SBP), diasolic BP (DBP), mean arterial pressure (MAP), time between the administration of neuromuscular blocking agent and endotracheal intubation was recorded. Results were analysed by the analysis of variance and chi square test. Results: Heart rate, SBP, DBP and mean arterial pressure were significantly higher in Group C as compared to Group M after laryngoscopy and endotracheal intubation (P&lt;0.05). The mean time required for onset of intubation was significantly shorter in Group C compared to Group M. Conclusion: The objective assessment of neuromuscular relaxation prior to endotracheal intubation provides better attenuation of hemodynamic responses. Keywords: hemodynamic response; laryngoscopy; endotracheal intubation; neuromuscular block