Anesthesia Monitoring Research Articles

Perioperative care in acute liver failure: An anaesthesiologist perspective in the operating theatre.

Acute liver failure (ALF) is a life-threatening condition characterized by rapid liver function deterioration, necessitating a multidisciplinary approach for optimal perioperative care. This comprehensive review focuses on the critical role of the anaesthesiologist throughout the preoperative, intraoperative, and postoperative phases, addressing the unique challenges posed by ALF. The article begins with an exploration of ALF, underlining the urgency of timely referral to specialized hepatology centres. Liver transplantation emerges as a life-saving intervention, and the complex decision-making process is discussed, emphasizing the need for a multidisciplinary team to assess transplantation candidacy based on established prognostic criteria. In the preoperative phase, the review stresses the importance of early engagement with tertiary liver centres for timely referrals and identifies patients suitable for transplantation. Safe transport protocols are detailed, highlighting the meticulous planning required for the secure transfer of ALF patients between healthcare facilities. The intraoperative management section delves into the anaesthesiologist's key concerns, including neurological status, sepsis, acute kidney injury, body mass index, and preoperative fasting. Hemodynamic stability, fluid management, and coagulation balance during surgery are emphasized, with insights into anaesthesia techniques, vascular access, monitoring, and hemodynamic management tailored to the challenges posed by ALF patients. The postoperative care is thoroughly examined covering neurological, hemodynamic, metabolic, renal, and nutritional aspects. Management of ALF involves multidisciplinary team, including nephrology for continuous renal replacement therapy, transfusion medicine for plasma exchange, critical care for overall patient care, nutritionists for ensuring adequate nutrition, and hepatologists as the primary guides. In conclusion, the review recognizes the anaesthesiologist as a linchpin in the perioperative care of ALF patients. The integration of safe transport protocols and multidisciplinary approach is deemed crucial for navigating complexities of ALF, contributing to improved patient outcomes. This article serves as an invaluable resource for gastroenterologist and intensivists, enhancing their understanding of the anaesthesiologist's indispensable role in the holistic care of ALF patients in an ever-evolving healthcare landscape.

Depth of anesthesia monitoring in Norway-A web-based survey.

The bispectral index (BIS) monitor is the most frequently used electroencephalogram (EEG)-based depth of anesthesia (DoA) technology in Norwegian hospitals. However, there is limited knowledge regarding the extent and clinical impact of its use and how anesthesiologists and nurse anesthetists use the information provided by the DoA monitors in their clinical practice. This cross-sectional survey on the use of DoA monitors in Norway used a web-based questionnaire distributed to anesthesia personnel in all hospitals in Norway. Participation was voluntary and anonymized, and the web form could not track IP sources or respondents' locations. Three hundred and ninety-one nurse anesthetists (n = 324) and anesthesiologists (n = 67) responded. Among the EEG-based DoA monitoring tools, BIS was most often used to observe and assess patients' DoA (98%). Raw EEG waveform analysis (10%), EEG-spectrogram (9%), and suppression rate (10%) were seldom used. Twenty-seven percent of the anesthesia personnel were able to recognize a burst suppression pattern on EEG and its significance. Fifty-eight percent of the respondents considered clinical observations more reliable than BIS. Almost all respondents reported adjusting anesthetic dosage based on the BIS index values (80%). However, the anesthetic dose was more often increased (90%) because of high BIS index values than lowered (55%) because of low BIS index values. Despite our respondents' extensive use of DoA monitoring, the anesthesia personnel in our survey did not use all the information and the potential to guide the titration of anesthetics the DoA monitors provide. Thus, anesthesia personnel could generally benefit from increased knowledge of how EEG-based DoA monitoring can be used to assess and determine individual patients' need for anesthetic medication.

Effect of Anesthesia Induction with Midazolam on Hemodynamics in Abdominal Hysterectomy Surgeries

Objective: The primary task of anesthesiology is to control the patient's hemodynamic values, including blood pressure and heart rate, from pre-operative to post-operative. Many drugs are used alone or in combination for induction and maintenance of anesthesia. Various hemodynamic responses may develop to these drugs. In our study, we aimed to compare the effects of midazolam and propofol used alone in intravenous anesthesia induction on hemodynamics in patients undergoing abdominal hysterectomy. Materials and Methods: A total of 60 ASA I-II patients scheduled for abdominal hysterectomy were included in the study. During anesthesia induction, midazolam (0.2 mg/kg) was administered to Group M (n:30) and propofol 1% (2 mg/kg) was administered to Group P (n:30). Noninvasive systolic blood pressure, diastolic blood pressure, mean blood pressure and minute heart rate values were recorded. Results: Systolic blood pressure was significantly lower in group P than in M during intubation, skin incision, extubation and recovery. Conclusion:As a result, anesthesia induction with intravenous 0.2 mg/kg midazolam may cause higher systolic blood pressure values than 2 mg/kg propofol. It should not be overlooked that the hemodynamic response that will occur after the use of midazolam during anesthesia monitoring will vary depending on the anesthetic drugs and doses used together.

Monitoring of general anesthesia by qCON and qNOX indices versus conventional clinical parameters in urological surgery: A randomized controlled clinical trial

Background: Awareness during anesthesia is a major anesthetic concern. Depth of anesthesia is commonly assessed in clinical practice by the patient’s clinical signs and symptoms such as blood pressure, heart rate variability, and body movement. At present, many studies have focused on qCON monitoring for sedative depth, but only a few studies have focused on qNOX monitoring for analgesic depth. Aims and Objectives: The aim of the present study was to evaluate the relative efficacy of qCON and qNOX versus commonly used vital signs such as blood pressure and heart rate in monitoring the anesthetic depth and analgesia. Materials and Methods: A total of 100 patients of either sex and of ASA Physical status I & II, scheduled for urogenital surgeries, were selected and randomly placed into two groups. Group A was monitored by conventional clinical technique and Group B was monitored by qCON and qNOX indices. The primary outcome was the total dose of propofol and fentanyl required to maintain the depth of anesthesia and analgesia. The secondary outcomes were propofol and fentanyl adjustment frequency, infusion duration, and quality of recovery from anesthesia. Results: Results showed statistically significant differences between the two groups in mean dose of both propofol (P=0.000) and fentanyl (P=0.006), adjustment frequency of both propofol (P=0.000) and fentanyl (P=0.010), time required to voluntary eye-opening (P=0.000) and extubation time (P=0.000) and visual analog scale score (P=0.000). There was no statistically significant difference found in infusion duration (P=0.317) and Ramsay Sedation Score (P=0.709) between the groups. Conclusion: Using the qCON and qNOX indices, an anesthesiologist can monitor the depth of anesthesia and analgesia more effectively and can adjust the anesthetic or analgesic drug dosing in a better possible way with lesser requirement of drugs than with conventional clinical monitoring.

Permutation Entropy Does Not Track the Electroencephalogram-Related Manifestations of Paradoxical Excitation During Propofol-Induced Loss of Responsiveness: Results From a Prospective Observational Cohort Study.

During the anesthetic-induced loss of responsiveness (LOR), a "paradoxical excitation" with activation of β-frequencies in the electroencephalogram (EEG) can be observed. Thus, spectral parameters-as widely used in commercial anesthesia monitoring devices-may mistakenly indicate that patients are awake when they are actually losing responsiveness. Nonlinear time-domain parameters such as permutation entropy (PeEn) may analyze additional EEG information and appropriately reflect the change in cognitive state during the transition. Determining which parameters correctly track the level of anesthesia is essential for designing monitoring algorithms but may also give valuable insight regarding the signal characteristics during state transitions. EEG data from 60 patients who underwent general anesthesia were extracted and analyzed around LOR. We derived the following information from the power spectrum: (i) spectral band power, (ii) the spectral edge frequency as well as 2 parameters known to be incorporated in monitoring systems, (iii) beta ratio, and (iv) spectral entropy. We also calculated (v) PeEn as a time-domain parameter. We used Friedman's test and Bonferroni correction to track how the parameters change over time and the area under the receiver operating curve to separate the power spectra between time points. Within our patient collective, we observed a "paradoxical excitation" around the time of LOR as indicated by increasing beta-band power. Spectral edge frequency and spectral entropy values increased from 19.78 [10.25-34.18] Hz to 25.39 [22.46-30.27] Hz (P = .0122) and from 0.61 [0.54-0.75] to 0.77 [0.64-0.81] (P < .0001), respectively, before LOR, indicating a (paradoxically) higher level of high-frequency activity. PeEn and beta ratio values decrease from 0.78 [0.77-0.82] to 0.76 [0.73-0.81] (P < .0001) and from -0.74 [-1.14 to -0.09] to -2.58 [-2.83 to -1.77] (P < .0001), respectively, better reflecting the state transition into anesthesia. PeEn and beta ratio seem suitable parameters to monitor the state transition during anesthesia induction. The decreasing PeEn values suggest a reduction of signal complexity and information content, which may very well describe the clinical situation at LOR. The beta ratio mainly focuses on the loss of power in the gamma-band. PeEn, in particular, may present a single parameter capable of tracking the LOR transition without being affected by paradoxical excitation.

Est-ce qu’il souffre ? Enjeux éthiques de l’introduction d’un dispositif d’hétéroévaluation du confort en fin de vie

Avoiding suffering for patients at the end of life is a central objective of the palliative care, which engages caregivers on a daily basis at the bedside of patients and their families. However, there are many limits to this objective, linked to the definition of suffering, to the difficulty of assessing the suffering of others, and finally to the solutions available for its management. In an attempt to unravel some of these issues, we address the challenges of assessing suffering in palliative care, through self-evaluation, hetero-evaluation and physiological measurements. We present a technical tool designed for pain monitoring in intensive care anesthesia. The ethical issues raised by the extension of its use to the palliative care relate to its validation, to what the tool does or does not show, and to the question of setting its threshold. It's a question of rethinking the place left to technique in the work of care in palliative care, and the way in which we construct support with it. We will open up perspectives by outlining the role that palliative care research can play in exploring these issues.

Study protocol: Cerebral characterization of sensory gating in disconnected dreaming states during propofol anesthesia using fMRI.

Disconnected consciousness describes a state in which subjective experience (i.e., consciousness) becomes isolated from the external world. It appears frequently during sleep or sedation, when subjective experiences remain vivid but are unaffected by external stimuli. Traditional methods of differentiating connected and disconnected consciousness, such as relying on behavioral responsiveness or on post-anesthesia reports, have demonstrated limited accuracy: unresponsiveness has been shown to not necessarily equate to unconsciousness and amnesic effects of anesthesia and sleep can impair explicit recollection of events occurred during sleep/sedation. Due to these methodological challenges, our understanding of the neural mechanisms underlying sensory disconnection remains limited. To overcome these methodological challenges, we employ a distinctive strategy by combining a serial awakening paradigm with auditory stimulation during mild propofol sedation. While under sedation, participants are systematically exposed to auditory stimuli and questioned about their subjective experience (to assess consciousness) and their awareness of the sounds (to evaluate connectedness/disconnectedness from the environment). The data collected through interviews are used to categorize participants into connected and disconnected consciousness states. This method circumvents the requirement for responsiveness in assessing consciousness and mitigates amnesic effects of anesthesia as participants are questioned while still under sedation. Functional MRI data are concurrently collected to investigate cerebral activity patterns during connected and disconnected states, to elucidate sensory disconnection neural gating mechanisms. We examine whether this gating mechanism resides at the thalamic level or results from disruptions in information propagation to higher cortices. Furthermore, we explore the potential role of slow-wave activity (SWA) in inducing disconnected consciousness by quantifying high-frequency BOLD oscillations, a known correlate of slow-wave activity. This study represents a notable advancement in the investigation of sensory disconnection. The serial awakening paradigm effectively mitigates amnesic effects by collecting reports immediately after regaining responsiveness, while still under sedation. Ultimately, this research holds the potential to understand how sensory gating is achieved at the neural level. These biomarkers might be relevant for the development of sensitive anesthesia monitoring to avoid intraoperative connected consciousness and for the assessment of patients suffering from pathologically reduced consciousness. European Union Drug Regulating Authorities Clinical Trials Database (EudraCT), identifier 2020-003524-17.

Assessment of seizure duration and utility of using SedLine® EEG tracing in veterans undergoing electroconvulsive therapy: a retrospective analysis

BackgroundElectroconvulsive therapy (ECT) endures as a definitive treatment for refractory depression and catatonia and is also considered an effective treatment for a number of other severe psychiatric disorders (Lisanby, N Engl J Med 357:1939-1945, 2007)(Weiner and Prudic, Biol Psychiatry 73:105-106, 2013). GA is an essential component of the ECT procedure for various reasons (Lee, Jenkins and Sparkle, Life 11, 2021). Monitoring anesthetic effects on the brain is desirable as anesthetic agents affect seizure duration and recovery (Rasulo, Hopkins, Lobo, et al, Neurocrit Care 38:296-311, 2023) (Jones , Nittur , Fleming and Applegate, BMC Anesthesiol 21:105, 2021) (Soehle , Kayser , Ellerkmann and Schlaepfer, BJA 112:695-702, 2013). Perioperative anesthetic effects on consciousness can be assessed with brain function monitoring using raw electroencephalogram (EEG) traces and processed EEG indices.ObjectiveWe examined the usefulness and utility of the SedLine® anesthetic effect monitor during ECT procedures. We hypothesized that the seizure duration as measured by the EEG tracing of the ECT machine is equivalent to the duration assessed by the SedLine® EEG tracing. A secondary objective was to describe the SedLine® patient state indices (PSI) at different phases of treatment.MethodsFollowing IRB approval, we analyzed the data of the electronic medical records of 45 ECT treatments of 23 patients in an urban VA medical center between July 01, 2021, and March 30, 2022. We compared the seizure duration in minutes and seconds as measured either by the ECT machine EEG tracing or the SedLine® EEG tracing. We then collected SedLine® processed EEG indices at four different stages during the treatment. Appropriate comparative and observational statistical analyses were applied.ResultsThere was no significant difference in measured seizure duration between the two methods examined (p < 0.05). We observed a lag of the SedLine PSI value at the time before stimulus delivery and limited PSI utility during the course of ECT.ConclusionThe SedLine® EEG tracing can be an alternative to the machine EEG tracing for the determination of seizure duration. The SedLine® processed EEG indices are not consistently useful before and after ECT delivery. Anesthetic effect monitoring during ECT is feasible.

The Effect of Topical Benzydamine Hydrochloride and Cuff Pressure Monitorization on Postoperative Sore Throat Due to Intubation.

Postoperative sore throat (POST) is the most common discomfort after endotracheal intubation. Damage to the tracheal mucosa caused by inappropriate endotracheal tube (ETT) cuff pressure has been shown as the major factor. Monitoring the ETT cuff pressure at a certain value reduces this damage. Benzydamine hydrochloride (BH) has proven to be effective on sore throat and studies have shown that it is also effective on POST. In this study, the efficacy of BH and ETT cuff pressure monitoring on POST was evaluated. After ethics committee approval 210 patients in the ASA (American Society of Anesthesiologists) I-III risk group undergoing elective surgery were included in the study. Routine anesthesia monitoring, induction, and maintenance were provided. Patients were randomly divided into three groups. Thirty minutes before surgery, the posterior pharyngeal wall was sprayed with BHin group 1and distilled water in groups 2 and 3. Intraoperatively, the first and second groups were monitored to keep the ETT cuff pressure between 22 and 26 cmH2O, while no intervention was performed in the third group. The incidence and severity of postoperative dysphagia, hoarseness, and POST were questioned. There was no difference between demographic data, and gender was not associated with POST. There was a statistically significant difference between the first and second groups and the third group in terms of all three symptoms questioned (p<0.01). No difference was observed between the first and second groups. Side effect rates were similar. Smoking was not found to be associated with symptoms. The incidence and severity of POST, dysphagia, and hoarseness are reduced when the ETT cuff is inflated with a pressure of 22-26 cmH2O after intubation with a manometer and maintained at this pressure range throughout the operation. There was no beneficial effect of BH.

Surface-Enhanced Raman Spectroscopy for Quantitative Analysis of Anesthetic Agents: Toward Personalized Drug Monitoring in Anesthesia

Surface-Enhanced Raman Spectroscopy for Quantitative Analysis of Anesthetic Agents: Toward Personalized Drug Monitoring in Anesthesia

Intraoperative pediatric electroencephalography monitoring: an updated review.

Intraoperative electroencephalography (EEG) monitoring under pediatric anesthesia has begun to attract increasing interest, driven by the availability of pediatric-specific EEG monitors and the realization that traditional dosing methods based on patient movement or changes in hemodynamic response often lead to imprecise dosing, especially in younger infants who may experience adverse events (e.g., hypotension) due to excess anesthesia. EEG directly measures the effects of anesthetics on the brain, which is the target end-organ responsible for inducing loss of consciousness. Over the past ten years, research on anesthesia and computational neuroscience has improved our understanding of intraoperative pediatric EEG monitoring and expanded the utility of EEG in clinical practice. We now have better insights into neurodevelopmental changes in the developing pediatric brain, functional connectivity, the use of non-proprietary EEG parameters to guide anesthetic dosing, epileptiform EEG changes during induction, EEG changes from spinal/regional anesthesia, EEG discontinuity, and the use of EEG to improve clinical outcomes. This review article summarizes the recent literature on EEG monitoring in perioperative pediatric anesthesia, highlighting several of the topics mentioned above.

To assess the safety of laparoscopy in patients with CSF catheters draining distally into the abdomen.

This study evaluates the safety of laparoscopic procedures in patients with cerebrospinal fluid (CSF) catheters draining distally into the abdomen. A systematic search across PubMed, Scopus, and Ovid databases using pertinent keywords yielded 47 relevant papers, encompassing 197 cases, for analysis. In the pediatric cohort (n = 129), male (49.6%) and female (34.1%) cases were reported, while gender remained unspecified in 16.3%. Shunt indications included unspecified (126 cases) and Meningomyelocele (3 cases). Laparoscopic procedures encompassed gastric (72.1%), urologic (21.7%), and other (6.2%) indications. Peri-operative shunt management included subcostal incision and clamping (1), ICP monitoring and drainage (2), and distal shunt flow confirmation (1). The prevalent complication was mechanical obstruction (10.1%), followed by pseudocyst formation (1.5%) and infection (2.3%). In the adult cohort (n = 61), males (60.6%) and females (39.3%) with a median age of 55 years were observed. Management strategies encompassed sponge packing and mobilization (11), distal shunt flow confirmation (2), shunt clamping (3), Transcranial Doppler monitoring (2), and no manipulation (30). Shunt infection emerged as the primary complication (2). Overall, 24 patients encountered VP shunt-related complications post-laparoscopy. This study underscores the safety of laparoscopic interventions in patients with ventriculoperitoneal or lumboperitoneal shunts when facilitated by interdisciplinary cooperation. A meticulous preoperative assessment for shunt track localization, intraoperative visualization of shunt tip with CSF flow, vigilant perioperative anesthetic monitoring, and shunt dysfunction surveillance are crucial for favorable outcomes in laparoscopic procedures for these patients.

Study of Total Intravenous Anaesthesia in laparoscopic Surgery

Background: Total intravenous anaesthesia in laparoscopic surgery is safer than open laparotomy operationsbecause propofol, a sedative hypnotic agent with excellent recovery drug and having anti-emetic properties, andnew synthetic opioids (fentanyl congeners) provide excellent analgesia; hence, TIVA has become more popular inlaparoscopic surgery.Method: 45 adult patients aged between 18 to 65 undergoing laparoscopic surgery were studied. A solutionof propofol containing different concentrations of sufentanil (1 μgm per ml and 2 μgmper ml) was infused.Patient’s HR, SBP, DBP, MAP, and peripheral O2 saturation from the anaesthesia monitor was taken as a baselinemeasurement. All the hemodynamic parameters were recorded intra-operatively at different intervals of duration.Results: The changes in mean values of hemodynamic values were insignificant, and only significant parameterswere noted. 158.12 (± 80.9) mean value time to rescue analgesia (in minutes) Post-surgical complications are 3(6.6%) Nausea and vomitingConclusion: Propofol, containing different concentrations of sufentanil, provides hemodynamic stability withthe least post-surgical complications; hence, total intravenous anaesthesia is an ideal substitute for inhalationanaesthesia in laparoscopic surgery because inhalation anaesthesia has a higher risk of hemodynamic instability.

Role of artificial intelligence in perioperative monitoring in anaesthesia.

Artificial intelligence (AI) is making giant strides in the medical domain, and the field of anaesthesia is not untouched. Enhancement in technology, especially AI, in many fields, including medicine, has proven to be far superior, safer and less erratic than human decision-making. The intersection of anaesthesia and AI holds the potential for augmenting constructive advances in anaesthesia care. AI can improve anaesthesiologists' efficiency, reduce costs and improve patient outcomes. Anaesthesiologists are well placed to harness the advantages of AI in various areas like perioperative monitoring, anaesthesia care, drug delivery, post-anaesthesia care unit, pain management and intensive care unit. Perioperative monitoring of the depth of anaesthesia, clinical decision support systems and closed-loop anaesthesia delivery aid in efficient and safer anaesthesia delivery. The effect of various AI interventions in clinical practice will need further research and validation, as well as the ethical implications of privacy and data handling. This paper aims to provide an overview of AI in perioperative monitoring in anaesthesia.

Correlations between preoperative fluid status assessed by bioimpedance analysis and hypotension during anaesthesia induction.

Hypovolaemia is presumed to be a common risk factor of postinduction hypotension (PIH), despite worldwide improvement in preoperative volume optimization. Correct assessment of fluid status in patients undergoing general anaesthesia remains a major challenge for anaesthesiologists. Bioimpedance analysis (BIA) is a sensitive method that allows objective assessment of patient fluid status as it can detect subclinical changes. The study's main purpose was to determine the correlation between the preoperative BIA assessed fluid status and PIH. This was an observational single centre study that included patients undergoing elective surgery. We defined PIH as the blood pressure decrease occurring during the first 10 minutes after induction of anaesthesia and orotracheal intubation before surgical incision. We standardized BIA evaluation, patient pre anaesthetic and preoperative preparation, technique and monitoring of anaesthesia. Our study included 115 patients. The mean age of the population was 58.1 years and the median values for total and intracellular water were 35.1 L and 19.3 L, respectively. In the univariable and multivariable analysis, only total body and intracellular water were associated with different definitions of PIH. There was no correlation between any of the BIA-derived parameters of fluid status and the duration of PIH. Our study shows that in elective surgery, bioimpedance could detect subtle, subclinical fluid parameters that are associated with PIH.

Kalman filtering to reduce measurement noise of sample entropy: An electroencephalographic study.

In the analysis of electroencephalography (EEG), entropy can be used to quantify the rate of generation of new information. Entropy has long been known to suffer from variance that arises from its calculation. From a sensor's perspective, calculation of entropy from a period of EEG recording can be treated as physical measurement, which suffers from measurement noise. We showed the feasibility of using Kalman filtering to reduce the variance of entropy for simulated signals as well as real-world EEG recordings. In addition, we also manifested that Kalman filtering was less time-consuming than moving average, and had better performance than moving average and exponentially weighted moving average. In conclusion, we have treated entropy as a physical measure and successfully applied the conventional Kalman filtering with fixed hyperparameters. Kalman filtering is expected to be used to reduce measurement noise when continuous entropy estimation (for example anaesthesia monitoring) is essential with high accuracy and low time-consumption.

Effectiveness Assessment of Bispectral Index Monitoring Compared with Conventional Monitoring in General Anesthesia: A Systematic Review and Meta‐Analysis

Background and Objective. The Bispectral Index (BIS) is utilized to guide the depth of anesthesia monitoring during surgical procedures. However, conflicting results regarding the benefits of BIS for depth of anesthesia monitoring have been reported in numerous studies. The purpose of this meta‐analysis and systematic review was to assess the effectiveness of BIS for depth of anesthesia monitoring. Search Methods. A systematic search of Ovid‐MEDLINE, Cochrane, and PubMed was conducted from inception to April 20, 2023. Clinical trial registers and grey literature were also searched, and reference lists of included studies, as well as related review articles, were manually reviewed. Selection Criteria. The inclusion criteria were randomized controlled trials without gender or age restrictions. The control groups used conventional monitoring, while the intervention groups utilized BIS monitoring. The exclusion criteria included duplicates, reviews, animal studies, unclear outcomes, and incomplete data. Data Collection and Analysis. Two independent reviewers screened the literature, extracted data, and assessed methodological quality, with analyses conducted using R 4.0 software. Main Results. Forty studies were included. In comparison to the conventional depth of anesthesia monitoring, BIS monitoring reduced the postoperative cognitive dysfunction risk (RR = 0.85, 95% CI: 0.73∼0.99, P = 0.04), shortened the eye‐opening time (MD = −1.34, 95% CI: −2.06∼−0.61, P &lt; 0.01), orientation recovery time (MD = −1.99, 95% CI: −3.62∼−0.36, P = 0.02), extubation time (MD = −2.54, 95% CI: −3.50∼−1.58, P &lt; 0.01), and postanesthesia care unit stay time (MD = −7.11, 95% CI: −12.67∼−1.55, P = 0.01) and lowered the anesthesia drug dosage (SMD = −0.39, 95% CI: −0.63∼−0.15, P &lt; 0.01).​ Conclusion. BIS can be used to effectively monitor the depth of anesthesia. Its use in general anesthesia enhances the effectiveness of both patient care and surgical procedures.

Balanced anesthesia in pigeons (Columba livia): a protocol that ensures stable vital parameters and feasibility during long surgeries in cognitive neuroscience.

In neuroscience, numerous experimental procedures in animal models require surgical interventions, such as the implantation of recording electrodes or cannulas before main experiments. These surgeries can take several hours and should rely on principles that are common in the field of research and medicine. Considering the characteristics of the avian respiratory physiology, the development of a safe and replicable protocol for birds is necessary to minimize side effects of anesthetic agents, circumvent technical limitations due to the insufficient availability of patient monitoring, and to maintain stable intraoperative anesthesia. Through the consistent and responsible implementation of the threeR principle of animal welfare in science ("Replace, Reduce, Refine"), we aimed to optimize experimental methods to minimize the burden on pigeons (Columba livia) during surgical procedures. Here, surgeries were conducted under balanced anesthesia and perioperative monitoring of heart rate, oxygen saturation, body temperature, and the reflex state. The protocol we developed is based on the combination of injectable and inhalative anesthetic drugs [ketamine, xylazine, and isoflurane, supported by the application of an opiate for analgesia (e.g., butorphanol, buprenorphine)]. The combination of ketamine and xylazine with a pain killer is established in veterinary medicine across a vast variety of species. Practicability was verified by survival of the animals, fast and smooth recovery quantified by clinical examination, sufficiency, and stability of anesthesia. Independent of painful stimuli like incision or drilling, or duration of surgery, vital parameters were within known physiological ranges for pigeons. Our approach provides a safe and conservative protocol for surgeries of extended duration for scientific applications as well as for veterinary medicine in pigeons which can be adapted to other bird species.

Is There a Risk of Stroke During Anterior Cervical Discectomy? A Randomized Controlled Trial.

To examine the effects of different retractor techniques for anterior cervical discectomy on cerebral oxygen saturation. In this study, a prospective comparative design was employed to examine the effects of different retractor techniques on a cohort of 48 adult patients with ASA I-II classification who underwent anterior cervical discectomy under general anesthesia. The study was conducted under assessor-blinded conditions, and the patients were divided equally into two groups: the self-retaining retractor group and the hand-held retractor group. In addition to standard anaesthesia monitoring, the utilization of cerebral oximetry monitoring was implemented for all patients. A total of 7 measurements were obtained at various stages, including preoperative, during anaesthesia induction, surgical positioning, surgical retraction, release of retractors, after correction of extension position, and prior to extubation. The main objective of this study was to evaluate the impact of neck position and surgical retraction on brain perfusion, as measured by regional cerebral oximetry. Sociodemographic data, duration of operation, hemodynamic parameters, bilateral regional cerebral oxygen saturation (rScO2), and Mini Mental State Examination (MMSE) scores did not differ significantly between the two groups. In both groups, the bilateral rScO2 decreased significantly with positioning and the left rScO2 decreased significantly following the installation of retractors. Only the left rScO2 increased significantly upon the release of both retractors. Following the correction of the neck position, bilateral rScO2 increased significantly in both groups (p < 0.001). The rScO2 of the left carotid artery was shown to significantly decrease due to the indirect impact of the retractors. After extending the head and neck, bilateral rScO2 values decreased significantly in both groups. However, despite this decline, there was no significant decrease in brain perfusion that would result in ischemia. The absence of a statistically significant distinction between the groups implies that it is unlikely to have an impact on brain perfusion.

An overview of unresolved issues in the perioperative management of liver transplant patients.

Over the past decade, the field of solid organ transplantation has undergone significant changes, with some of the most notable advancements occurring in liver transplantation. Recent years have seen substantial progress in preoperative patient optimization protocols, anesthesia monitoring, coagulation management, and fluid management, among other areas. These improvements have led to excellent perioperative outcomes for all surgical patients, including those undergoing liver transplantation. In the last few decades, there have been numerous publications in the field of liver transplantation, but controversies related to perioperative management of liver transplant recipients persist. In this review article, we address the unresolved issues surrounding the anesthetic management of patients scheduled for liver transplantation.