Anesthetic Dose Research Articles

The impact of erector spinae plane (ESP) block on neurophysiological monitoring in patients undergoing scoliosis repair

ABSTRACT Background Preventive analgesia is designed to ensure perioperative pain control. The erector spinae plane (ESP) block may abolish the neuroendocrine stress response and augments controlled hypotensive anesthesia. But to what extent does it interfere with spinal cord function. Methods The patient’s population is divided into Group N (control) and Group E (ESP Group). A baseline for the amplitude and/or latency of either somatosensory evoked potentials (SSEPs) or motor evoked potentials (MEPs) were collected (30 min after induction of anesthesia and after full reverse of muscle relaxant before performing ESP block) in group E, the change from the baseline was recorded as a percent decrease. The total dose of anesthetics, the adjuvant analgesics and the postoperative complications were recorded. Results The change in the latency and the amplitude of SSEPs and MEPs among the two groups showed a non-significant change from the baseline. The intra-operative fentanyl consumption was significantly lower in group E than in C. The mean was 21.5 ± 25 vs 178.2 ± 46 mg respectively. The total doses of propofol and dexmedetomidine were lower in group E than in C. 18% of the patients in group E requested a rescue analgesic at a median of 70 (65) min postoperatively vs 55% of those in group C that requested analgesics earlier at a median 16(6) min. Conclusion The ESP block can be safely used without interfering with the monitoring of the somatosensory and MEPs during complex spinal surgery.

Inadequate Spinal Anesthesia in Lumbar Spine Surgery Is Related to Volume of the Thecal Sac

Spinal anesthesia (SA) is used in lumbar surgery but initial adequate analgesia fails in some patients. In these cases, spinal redosing or conversion to general endotracheal anesthesia is required, both of which are detrimental to the patient experience and surgical workflow. We reviewed cases of lumbar surgery performed under spinal anesthesia from 2017 - 2021. We identified 12 cases of inadequate first dose, then selected 36 random patients as controls. We used a measurement tool to approximate the volume of the dural sac for each patient using T2-weighted sagittal MRI sequences. Patients who had an inadequate first dose of anesthesia had a significantly larger dural sac volume, 22.8 ± 7.9 cm3 in the inadequate dose group, and 17.4 ± 4.7 cm3 in controls (p=0.043). The inadequate dose group was significantly younger, 54.2 ± 8.8 years in failed first dose, and 66.4 ± 11.9 years in control (p=0.001). The groups did not differ by surgical procedure (p=0.238), level (p=0.353), ASA score (p=0.546), or co-morbidities. We found that age, larger height, and dural sac volume are risk factors for an inadequate first dose of SA. The availability of spinal MRI in patients undergoing spine surgery allows the preoperative measurement of their thecal sac size. In the future, this data may be used to personalize spinal anesthesia dosing based on individual anatomic variables and potentially reduce the incidence of failed spinal anesthesia in spine surgery.

Ketamine and fluoxetine exert similar actions on prelimbic and infralimbic responsivity to lateral septal nucleus stimulation in Wistar rats

Ketamine is a dissociative anesthetic that has been proposed to be a useful alternative in cases of a poor response to other treatments in patients with depression. Remarkably, beneficial clinical actions of ketamine are detected once its psychotropic actions disappear. Therefore, clinical actions may occur independently of dose. Most current studies focus on actions of ketamine on neurotrophic factors, but few studies have investigated actions of ketamine on neural structures for which actions of antidepressants have been previously explored. Lateral septal nucleus (LSN) stimulation reduces neural activity in the prelimbic cortex (PL) and infralimbic cortex (IL) subregions of the medial prefrontal cortex (mPFC). Fluoxetine increases inhibitory responsivity of the LSN-IL connection. In the present study, actions of an anesthetic dose of ketamine were compared with a high dose of fluoxetine on behavior and neural responsivity 24 h after drug administration. Fluoxetine reduced immobility in the forced swim test without changing locomotor activity in the open field test. Ketamine strongly decreased locomotor activity and did not produce changes in immobility. In another set of Wistar rats that received similar drug treatment regimens, the results indicated that LSN stimulation in saline-treated animals produced a long-lasting inhibitory afterdischarge in these mPFC subregions. Actions of ketamine on the LSN-mPFC connection reproduced actions of fluoxetine, consisting of accentuated inhibition of the LSN action on the mPFC. These findings suggest that independent of different actions on neurotransmission, the common final pathway of antidepressants lies in their actions on forebrain structures that are related to emotional regulation.

Evaluating Dentists' Knowledge and Practices in the Use of Local Anesthetics and Unintended Effects in Pediatric Patients

Objective: This cross-sectional study aimed to evaluate a group of Turkish dentists' awareness, preparedness, and competence regarding the unintended effects of LAs in pediatric patients. Methods: In this study, the questionnaire form titled ' Evaluation of the Knowledge Level of Dentists Regarding the Use of Local Anesthesia and its Unintended Effects in Pediatric Patients' prepared in a digital environment was sent to dentists via Google survey application. The study investigated dentists' awareness and knowledge of the maximum dose of local anesthetic (LA) drugs. The most commonly used LA drugs and the most common complications related to these anesthetics were also determined. Results: According to the results obtained, the dentists' most frequently preferred LA substances were Articaine+Adrenaline (A+A) and Lidocaine+Adrenaline (L+A). It was found that 91% of the participants performed aspiration before LA applications. It was found that 74% of the dentists participating in the study did not calculate the maximum dose per kilogram when performing local anesthesia in pediatric patients. The three complications encountered by the participating dentists during local anesthesia were found to be anesthetic failure (73%), facial paralysis (26%), and syncope (19%), respectively. In addition, 90% of the dentists who were asked about the first drug they would prefer in anaphylaxis answered adrenaline. When asked about the route of adrenaline injection, the majority of the dentists (64%) responded intramuscularly. Conclusion: Although the occurrence of anaphylaxis during dental procedures is rare, when it does occur, it can lead to severe complications that may result in death. Dentists should be familiar with the signs of systemic complications that may arise from using LAs. When these findings are encountered after anesthesia, it should be considered that a systemic complication may have occurred, and urgent intervention should be performed. Any delay may cause consequences that may threaten the patient's life. This subject, which is of critical importance in dentistry, should be considered more in undergraduate and postgraduate education, and the level of knowledge should be increased by providing further training courses to update the information.

Spatio-temporal electroencephalographic power distribution in experimental pigs receiving propofol.

When assessing the spatio-temporal distribution of electroencephalographic (EEG) activity, characteristic patterns have been identified for several anesthetic drugs in humans. A shift in EEG power from the occipital to the prefrontal regions has been widely observed during anesthesia induction. This has been called "anteriorization" and has been correlated with loss of consciousness in humans. The spatio-temporal distribution of EEG spectral power in pigs and its modulation by anesthetics have not been described previously. The aim of the present study was to analyze EEG power across an anterior-posterior axis in pigs receiving increasing doses of propofol to 1) characterize the region of highest EEG power during wakefulness, 2) depict its spatio-temporal modification during propofol infusion, and 3) determine the region demonstrating the most significant modulations across different doses administered. Six pigs with a body weight of 33.3 ± 3.6 kg and aged 11.3 ± 0.5 weeks were included in a prospective experimental study. Electroencephalographic activity was collected at the occipital, parietal and prefrontal regions at increasing doses of propofol (starting at 10 mg kg-1 h-1 and increasing it by 10 mg kg-1 h-1 every 15 minutes). The EEG power was assessed using a generalized linear mixed model in which propofol doses and regions were treated as fixed effects, whereas pig was used as a random effect. Pairwise comparisons of marginal linear predictions were used to assess the change in power when the specific propofol dose (or region) was considered. During both wakefulness and propofol infusion, the highest EEG power was located in the prefrontal region (p<0.001). The EEG power, both total and for each frequency band, mostly followed the same pattern, increasing from awake until propofol 20 mg kg-1 h-1 and then decreasing at propofol 30 mg kg-1 h-1. The region showing the strongest differences in EEG power across propofol doses was the prefrontal. In juvenile pigs receiving increasing doses of propofol, the prefrontal region showed the highest EEG power both during wakefulness and propofol administration and was the area in which the largest frequency-band specific variations were observed across different anesthetic doses. The assessment of the spectral EEG activity at this region could be favorable to distinguish DoA levels in pigs.

Effects of Continuous Analgesic Titrated Spinal Anesthesia in Elderly Patients Undergoing Hip Fracture Surgery

Background and Objectives: Anesthetizing elderly patients with hip fractures poses a significant challenge in emergency settings, particularly given the aging population both in Algeria and worldwide. With a high prevalence of comorbidities and polypharmacy, effective anesthetic management becomes paramount. Continuous titrated spinal anesthesia (CTSA) has emerged as a promising technique for addressing these complexities by proposing lower doses of local anesthetic (LA) in this patient population. Methods: This retrospective study involved 40 elderly patients (&gt;65 years) undergoing hip fracture repair. Patients received intermittent dosing of a local anesthetic solution via an intrathecal catheter, utilizing 0.25 ml increments of 0.5% isobaric bupivacaine and 0.25 ml of fentanyl (12.5 μg). Evaluation criteria included hemodynamic stability, incidence of hypotension, extent of sensory and motor blockade, total ephedrine consumption, and patient and surgeon satisfaction. Results: A female predominance was noted, with a mean age of 75 years, and 72% classified as ASA ≥ III. Pertrochanteric fractures accounted for 47% of cases, followed by femoral neck fractures at 53%. Nearly all patients achieved a sensory level ≥ D10, with a failure rate of only 2%. Sedation supplementation was required in 20% of cases, with conversion to general anesthesia in one patient. Complications were minimal, including arterial hypotension (3%), vasoconstrictor use (2%), and bradycardia (0.8%). Overall, both patients and surgeons reported high levels of satisfaction. Conclusions: Our findings demonstrate that CTSA is an effective technique for elderly patients undergoing hip fracture repair, offering the advantages of reduced LA doses, excellent hemodynamic stability, and minimal side effects. Its simplicity and cost-effectiveness further enhance its appeal in clinical practice.

Abstract PO2-01-12: Preoperative cryoablation in 52 Her2- Luminal invasive ductal carcinomas ≤ 2cm. Analysis of the tumor specimen

Abstract Objective: 1st: Assess the presence of residual infiltrating component in the surgical specimen of patients with Luminal Her2- tumors ≤ 2cm and ultrasound-negative axilla, following ultrasound-guided cryoablation. 2nd: Demonstrate that preoperative seed placement prior to cryoablation does not interfere with tumor cell elimination by freezing. Methods: Between April 2021 and April 2023, we performed preoperative cryoablation on 52 patients aged 53 to 79 years (mean 64) with 52 unifocal invasive ductal carcinomas (IDC) measuring 4 to 20 mm (mean 10), low grade (24 G1, 28 G2), 31 Luminal A and 21 B, Ki67 between 3 and 30% (mean 13). On ultrasound, all IDCs were visible and axilla-negative. 26 of them (50%) were referred from the screening program of the Community of Madrid. The tumor-to-skin surface distance ranged from 2 to 18 mm (mean 9 mm). All patients underwent mammography-tomosynthesis, staging, and biopsy under ultrasound guidance. The minimum time elapsed until surgery was 6 days, and the maximum was 78 days (mean 22). All patients underwent mammography-tomosynthesis, staging, and biopsy under ultrasound guidance. MRI was performed to rule out extensive intraductal component in 17 out of 20 patients with associated intraductal carcinoma (IDC) in the diagnostic biopsy. Preoperative marking with ferromagnetic seed placement was performed in all cases prior to cryoablation, using a single dose of anesthesia and through the same skin access. We used the ICEfx Galil Boston Scientific cryoablation system with 17G or 14G needles, applying the standard triple-phase protocol: freezing-passive thawing-freezing for approximately 40 minutes. The correct placement of the seed was subsequently confirmed by mammography. Results: There were no significant complications in any case. Out of 52 low-risk unifocal IDCs: -32 were pure IDCs (without associated intraductal component in diagnostic biopsy): no residual IDC was identified in the tumor specimen. -20 were mixed IDCs (with associated IDC in the diagnostic biopsy): *In 4 cases, residual IDC was found in the surgical specimen, with some foci of IDC remaining at the periphery of the post-cryoablation necrosis. *In 8 patients, foci of IDC were detected distant from the cryoablation zone. The pathologist determined that all samples had tumor-free margins. Conclusions: Cryoablation is effective in 100% of cases for pure infiltrating tumors ≤ 2cm. The presence of scattered IDC nests away from the cryoablation zone or at the margin of fat necrosis does not indicate technique failure, as all surgical specimens were determined to have tumor-free margins by the pathologist. For mixed infiltrating tumors, the ice ball should broadly cover the tumor size estimated by ultrasound and MRI. Standard adjuvant treatment will equalize the risk of recurrence with conventional lumpectomy. Table 1: 52 cases IDC unifocal ≤2cm Table 2: IDC Pure ≤2cm. Table 3: IDC mixed: IDC+DCIs ≤2cm Analysis of surgical specimen Citation Format: Maria José Roca Navarro, Pilar Zamora, Ylenia Navarro Monforte, Diego Garrido Alonso, Vicenta Córdoba Chicote, Teresa Diaz de Bustamante Durban, José María Oliver Goldaracena, Laura Yebenes Gregorio, Covadonga Marti, Jose Ignacio Sanchez-Mendez, Elisa Moreno, Laura Frías Aldeguer, Adolfo Loayza Galindo, Alberto Berjón García, Marcos Melendez Gisper, Carmen Martín Hervás, Lara Miralles, Cristina Escabias del Pozo, Younes Abadi, Elisa York Pineda, Gonzalo Garzón Moll, David Hardisson Hernáez, Alicia Hernández Gutiérrez, César Casado Sánchez, Virginia Martínez Marín, Shirin Zarbakhsh, Joaquin Gomez Ramirez. Preoperative cryoablation in 52 Her2- Luminal invasive ductal carcinomas ≤ 2cm. Analysis of the tumor specimen [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-01-12.

Intelligent algorithm based on deep learning to predict the dosage for anesthesia: A study on prediction of drug efficacy based on deep learning.

Anesthetic drugs play a vital role during surgery, however, due to individual differences and complex physiological mechanisms, the prediction of anesthetic drug dosage has always been a challenging problem. In this study, we propose a model for predicting the dosage of anesthetic drugs based on deep learning to help anesthesiologists better control their dosage during surgical procedures. We design a model based on the artificial neural network to predict the dosage of preoperative anesthetic, and use the SELU activation function and the loss function for weighted regularization to solve the problem of unbalanced sample. Moreover, we design a CNN-based model for the prior extraction of intraoperative features by using a 7 × 1 convolution kernel to enhance the receptive field, and combine maximum pooling and average pooling to extract key features while eliminating noise. A predictive model based on the LSTM network is designed to predict the intraoperative dosage of the anesthetic, and the bidirectional propagation-based LSTM network is used to improve the ability to learn the trend of changes in the physiological states of the patient during surgery. An attention module is added before the connection layer to appropriately attend to areas containing prominent features. The results of experiments showed that the proposed method reduced values of the MAPE to 15.83% and 12.25% compared with the traditional method in predictions of the preoperative and intraoperative doses of the anesthetic, respectively, and increased the values of to 0.887 and 0.915, respectively. The intelligent anesthesia prediction algorithm designed in this study can effectively predict the dosage of anesthetic drugs needed by patients, assist clinical judgment of anesthetic drug dose, and assist the anesthesiologists to ensure the smooth progress of the operation.

6301717 Evaluation of current practice of local anaesthetic dose in relation with height and weight for caesarean sections

6301717 Evaluation of current practice of local anaesthetic dose in relation with height and weight for caesarean sections

PHARMACOGENETICS OF ANESTHESIOLOGICAL SUPPORT

Pharmacogenetics studies the relationship between a person’s individual genetic characteristics and the human body’sresponse to the action of various drugs, particularly the occurrence of undesirable side eff ects. Thanks to the development of the latest technologies and methods, this branch of medical genetics and clinical pharmacology is developing very actively. Data are being accumulated, special databases are being created with the aim of creating individual genetic passports in the future, which will allow the selection of personalized treatment schemes.Anesthesiology is a special area of pharmacogenetic research because, more than any other medical specialty, it ischaracterized by polypharmacy-the simultaneous or sequential administration of many drugs. The same dose of a drug may be inadequate for some patients and may be life-threatening or cause unwanted side eff ects for others. Today, information about genetic factors is being used by clinicians to prescribe drugs to tailor drug therapy to a patient’s genome. In anesthesiology, the principles of pharmacogenetics have been explained for neuromuscular blocking agents, opioid metabolism, different types of anesthetics, and postoperative nausea and vomiting. On the other hand, a large number of anesthetics have a narrow therapeutic index.This review summarizes the most recent data from the scientifi c literature on the pharmacogenetics of diff erent types ofanesthetics. Inhalational anesthetics are halogenated derivatives of methyl ethyl ether, the exact mechanism of action of which is not yet fully understood. One of the rare but very serious side eff ects of all halogenated anesthetics is malignant hyperthermia, a genetically determined autosomal dominant disorder that manifests as a hypermetabolic response to drug administration. The dosage of intravenous anesthetics should also be carefully determined, taking into account the patient’s age, cardiovascular, hepatic, and renal status, concomitant drug therapy, and genetic factors. Ontogeny and genetic variability of drug-metabolizing enzymes are interrelated because genetic variability in drug-metabolizing enzyme expression cannot be assessed until the required protein is suffi ciently expressed. Pharmacogenetic variants may contribute to unpredictable drug exposure at the same weight- based drug dose.There are a number of potentially clinically applicable pharmacogenetic data in newborns, but more research is needed toconfi rm these fi ndings and understand how to incorporate them into clinical care.The selection of drugs and dosing regimens based on a patient’s pharmacogenomic profi le may be an important part of thefuture of medicine. Personalized treatment based on the specifi c variants in the genome will ultimately reduce the incidence of side eff ects and length of hospital stay for patients and save healthcare costs. Although pharmacogenomics and its application in clinical practice are still in their infancy, different variants and their implications for many clinical areas, including anesthesiology, are emerging every day.

Incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery: a multi- center prospective observational study

BackgroundFailed spinal anaesthesia causes prolonging of operation time, insufficient analgesia for surgery and needs repeating spinal anaesthesia which in turn causes local anaesthesia toxicity, high spinal and total spinal, and conversion to general anaesthesia. However, the problem remains unexplored in Amhara regional state comprehensive specialized hospitals.ObjectiveTo determine incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery in selected Amhara National Regional State comprehensive specialized hospitals, Northwest Ethiopia, 2023.MethodsMulti-center prospective observational study was conducted. Data was collected using questionnaire and checklist. All consecutive scheduled emergency and elective patients were included in the study. Data was transformed from Epi data to SPSS and logistic regression analysis was done. Both crude and adjusted odds ratio were used to assess the strength of association. Variables with a p-value of less than 0.05 were considered as statistically significant.ResultsA total of 532 patients were included in this study with a response rate of 98%. Incidence of failed spinal anaesthesia was 22.4% (CI = 19-25.9). Emergency surgery (AOR = 7.01, CI = 4.5–12.7), dose of bupivacaine of ≤ 10 mg (AOR = 3.02, CI = 1.3–10.2), work experience of anaesthetist < 2 years (AOR = 3.1, CI = 1.7–5.72), bloody CSF (AOR = 8.5, CI = 2.53–18.5), hyperbaric local anaesthetic drug (AOR = 3.3, 95% CI = 3.2–8.2) and local anaesthetist without adjuvants (AOR = 5.25, CI = 2.62–14.2) were associated failed spinal anaesthesia.Conclusion and recommendationThe incidence of failed spinal anaesthesia was high in Amhara Region comprehensive specialized hospitals. We suggest that anaesthesia providers should minimize failure by using adjuvants and appropriate dose of local anaesthetic. Additionally, simulation training should be given for anaesthesia trainees to improve their skills and to produce competent professionals.

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.

Comparison of diffusion ranges at different local anesthetic volumes during superior laryngeal nerve block

ObjectivesUltrasound-guided superior laryngeal nerve (SLN) block is a practical and painless approach to avoid the hemodynamic stress response during endotracheal intubation and relieve sore throat after laryngeal surgery. The main purpose of this study was to establish an optimal dosage of local anesthetic when performing SLN block to help anesthetists balance analgesia and side effects.MethodsTwenty fresh larynx specimens were obtained immediately after resection and then injected with 2-, 3-, 4-, or 5- mL of a lidocaine-blue dye mixture at bilateral SLN puncture sites. Superficial areas of deposited blue dye were measured. Dye leakage and surrounding dyed tissue were recorded. Another 40 patients were included in the ultrasound investigation. Distances between the internal branch of the SLN (iSLN) and adjacent structures were calculated.ResultsThe dye spread area was greater with the administration of larger doses, especially to the visceral space. A 2- or 3-mL injection of local anesthetic was sufficient to infiltrate the SLN gap. A higher incidence of dye leaking out of the thyrohyoid membrane and anterior epiglottis space was observed; furthermore, there was substantially more dyed hyoid/thyroid cartilage with 4 and 5 mL of injected dye mixture than 2 mL. There was no significant difference between the specimen and ultrasound measurements of for length of iSLN-adjacent structures.ConclusionsIn the Chinese population, 2- or 3- mL of local anesthetic is a safe dose during SLN block. A larger volume could overflow from the cavity to cause complications. The thyrohyoid membrane combined with the superior laryngeal artery is a reliable target for positioning the iSLN during ultrasound-guided regional anesthesia.

Adjusting and validating a procedure for parenteral anaesthesia in neonatal mice.

For neonatal pups, parenteral anaesthesia is said to be not reliable as low doses induce no anaesthesia whereas high doses render high mortality rates. In this work we have adapted parenteral anaesthesia procedures approved for pups >7 days of age, to anaesthetize neonatal animals (postnatal days 3-4; P3-P4) for keeping them immobile for a long period. In our first experiment we analysed the behaviour of P3-P4 mouse pups for 70 min after intraperitoneal administration of low (37.5/3.75 mg/kg) or high (50/5) doses of a ketamine/xylazine anaesthetic mixture, both in the low range as compared with dosages employed in adults. Pups became immobile in ≈7 min and remained immobile for ≈45 min, irrespective of the age and dose of anaesthesia, younger pups (P3) being apparently more sensitive to the dosage. In the second experiment, we studied the response of P3 pups to mildly nociceptive stimulations, performed with a 4.0 g von Frey filament applied to the dorsal aspect of their paws. These stimuli elicited reaction in 100% of the cases in non-anaesthetized pups. The results indicate that the high dose significantly reduced responses as compared with the low dose of anaesthesia. With the low dose, <40% of the pups were unresponsive to nociceptive stimulation, whereas the high dose resulted in 50-60% of the animals not responding. Mortality was low irrespective of age or dose, suggesting that doses can be further increased if needed for invasive experimental procedures.

Magnesium Sulfate and Its Versatility in Anesthesia: A Comprehensive Review.

In the field of general anesthesia, magnesium sulfate (MgSO4) has become a valuable adjunct because it provides a range of benefits that enhance and optimize conventional aesthetic procedures. This review highlights the various intra-anesthetic benefits of MgSO4 while examining its complex function in the treatment using anesthesia. Magnesium inhibits the release of acetylcholine at the motor endplate and blocks calcium channels at presynaptic nerve terminals. This reduces the amplitude of endplate potential and the excitability of muscle fibers, which increases the potency of a neuromuscular blockade by nondepolarizing neuromuscular blockers. This activity may lessen the need for primary muscle relaxants. Moreover, its capacity to potentially reduce the total amount of main aesthetic agents needed emphasizes its function in maximizing anesthesia dosage, ensuring sufficient depth while perhaps potentially reducing adverse effects linked with increased dosages. MgSO4's adaptable qualities present a viable path for improving anesthetic outcomes, possibly improving patient safety and improving surgical results.

MULTIMODAL ANESTHESIA AS AN IMPORTANT COMPONENT OF ERAS

Introduction. The ideology of Fast Track-Surgery (FTS) and Enhanced Recovery After Surgery (ERAS) represents modern trends in global surgical practice. Anesthesiology aims to provide ideal and universal solutions for protecting patients from surgical aggression. A multimodal approach, which includes multilevel, multifaceted antinociception, is well-founded, where maximum effectiveness is combined with minimal side effects.&#x0D; The aim. To analyze the issue of multimodal pain management as an important component of ERAS (Enhanced Recovery After Surgery) from modern sources of literature for optimizing perioperative care in the minimally invasive surgery department.&#x0D; Materials and methods. Bibliosemantic, comparative, and systemic analysis methods were employed. The proposed recommendations were developed based on an analysis of modern literature, the results of randomized trials and meta-analyses, as well as our own studies dedicated to the study of perioperative pain issues.&#x0D; The results. It has been proven that the use of opioids in anesthesia practice is decreasing. New and modern methods of continuous monitoring of vital organs in patients are being introduced as supplements to classical monitoring protocols. These methods are used to avoid excessive or inadequate dosing of anesthetics, adjust the concentration of substances used, reduce post-anesthesia complications, and improve patient comfort. The method of perioperative energy monitoring significantly complements the "International Standards for Safe Anesthetic Practice", WFSA (2010), and enhances perioperative patient safety by detecting metabolic disturbances and implementing appropriate pathogenetic correction. The importance of regional anesthesia under ultrasound control, nociception-antinociception balance management, and the impact of these methods on opioid consumption, patient satisfaction, and postoperative recovery have been proven.&#x0D; Conclusions. The most commonly used combination of drugs for multimodal analgesia often includes acetaminophen and NSAIDs (strong recommendation). It has been proven that deep and prolonged sedation in intensive care unit (ICU) patients is associated with worse outcomes, longer mechanical ventilation duration, extended ICU and hospital stays, and higher rates of complications, including infections and sometimes even death.

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 &amp; 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.

Efficacy of transversus abdominis plane block on postoperative nausea and vomiting: a meta-analysis of randomized controlled trial

BackgroundPostoperative nausea and vomiting (PONV) is a common postoperative complication, and Transversus abdominis plane (TAP) block can provide effective analgesia for surgical operation. However, but there is not enough evidence to prove its advantage for nausea and vomiting. The objective of this meta-analysis was to evaluate the efficacy of TAP block on PONV.MethodsTwo independent researchers conducted searches for randomized controlled trials (RCTs) in PubMed, Embase, and Cochrane Central Register of Controlled Trials. We used Review Manager software for meta-analysis.ResultsIn this meta-analysis, twenty-six trials with 1981 patients were examined. The results showed that TAP block reduced postoperative nausea (Risk Difference (RD) = -0.10, 95% confidence interval (CI): -0.15 to -0.05) compared with no TAP block. TAP block reduced the dose of fentanyl (Standardized Mean Difference (SMD) = -1.17, 95% CI: -2.07 to -0.26) and morphine (SMD = -1.12, 95% CI: -2.10 to -0.13) compared with no TAP block, when the timing of administration was before surgery (RD = -0.13, 95% CI: -0.19 to -0.07). TAP block reduced postoperative nausea when the ropivacaine dosage is ≤ 100 mg (RD = -0.13, 95% CI: -0.21 to -0.06), bupivacaine dosage ≥ 100 mg ( RD = -0.08, 95% CI: -0.13 to -0.03), and when the ropivacaine concentration was ≤ 0.375% (RD = -0.11, 95% CI: -0.18 to -0.04). TAP block significantly reduced the incidence of nausea when the types of opioid drugs in PCA is tramadol (RD = -0.13, 95% CI: -0.24 to -0.03). TAP block could reduce the VAS (SMD= -0.99, 95% CI: -1.29 to -0.70) and reduce the time of extubation (SMD = -0.71, 95% CI: -1.34 to -0.08).ConclusionThe meta-analysis conducted in this study revealed that TAP block could reduce the incidence of PONV, and the efficacy of TAP block may be influenced by factors such as administration time, local anesthetic dosage and concentration, types of opioid drugs in PCA.

Risk factors for postoperative nausea and vomiting after video-assisted thoracic surgery esophagectomy: a prospective cohort study.

Video-assisted thoracic surgery esophagectomy (VATS-E) may increase the risk of postoperative nausea and vomiting (PONV) because it uses a high dosage of anesthesia through a long operative duration. However, no study has examined the risk factors for PONV after VATS-E. Therefore, we investigated the risk factors for PONV to support the appropriate risk management of PONV after VATS-E. This prospective cohort study included 155 patients who underwent VATS-E at the Showa University Hospital between April 1st, 2020 and November 30th, 2022. The primary outcome was the incidence of PONV within 24 h after surgery. Significant independent risk factors associated with the incidence of PONV were selected using multivariate analysis. The association between the number of risk factors for PONV and incidence of PONV was analyzed. One-hundred fifty-three patients were included in the analysis. The patients' median age was 67 years (range, 44-88), and 79.1% were male. PONV occurred in 35 (22.9%) patients. In the multivariate analysis, remifentanil dosage > 89.0 ng/kg/ min, albumin ≤ 3.5 g/dL, and eGFR < 60 mL/min/1.73 m 2 were independent significant risk factors for PONV. A significant association was observed between the incidence of and the number of risk factors for PONV (0 factor, 5.8%; 1 factor, 27.3%; ≥ 2 factors, 40.0%; p = 0.001). These three risk factors are useful indicators for selecting patients at high risk of developing PONV after VATS-E. In these patients, avoiding the development of PONV will be possible by performing appropriate risk management.