General Anesthetic Agents Research Articles

The role of microglia in neurocognitive deficits induced by general anaesthetic agents during neurodevelopment

AbstractBackground and AimsMicroglia are the innate immune cells of central nervous system which play critical roles in brain homeostasis. Recently, the effects of general anesthetic agents (GAAs) on microglia and their potential neurotoxicity in neurodevelopment have attracted the attention of anesthesiologists and neuroscientists.MethodsHere, we review the physiology of microglia in neurodevelopment, the potential mechanisms of GAAs on microglia and the consequent changes in microglial function.OutcomesMicroglia‐mediated neuroinflammation is a key mechanism of neurocognitive deficits during neurodevelopment. In addition, microglia could be primed by active inflammatory processes and have innate immune memory, both of which make them a potential candidate responsible of long‐term neural deficits.ConclusionThis review aims in summarizing the in vivo and in vitro studies associating microglia with general anesthesia and describing how GAAs induce neurocognitive deficits via microglia to further explore the effects of GAAs on neurodevelopment.

A narrative review of gas separation and conservation technologies during xenon anesthesia.

Xenon gas has significant advantages over conventional general anesthetic agents but its use has been limited by the cost associated with its production. Xenon also has significant potential for medical use in the treatment of acquired brain injuries and for mental health disorders. As the demand for xenon gas from other industries increases, the costs associated with its medical use are only likely to increase. One solution to mitigate the significant cost of xenon use in research or medical care is the conservation of xenon gas. During delivery of xenon anesthesia, this can be achieved either by separating xenon from the other gases within the anesthetic circuit, conserving xenon and allowing other gases to be excluded from the circuit, or by selectively recapturing xenon utilized during the anesthetic episode at the conclusion of the case. Several technologies, including the pressurization and cooling of gas mixtures, the utilization of gas selective membranes and the utilization of gas selective adsorbents have been described in the literature for this purpose. These techniques are described in this narrative review along with important clinical context that informs how these technologies might be best applied. Whilst these technologies are discussed in the context of xenon general anesthesia, they could be applied in the delivery of xenon gas inhalation for other therapeutic purposes.

Successful Management of an Acute Dystonic Reaction Induced by an Anesthetic Agent

Acute dystonic reactions (ADRs) are movement abnormalities characterized by involuntary muscle contractions that typically manifest after exposure to a triggering agent, such as a medication. The specific muscle groups affected determine the type of reaction. For instance, an oculogyric crisis primarily affects the ocular muscles, while oromandibular dystonia involves jaw opening and tongue protrusion. We present the rare case of a 68-year-old man with amyotrophic lateral sclerosis who was successfully treated for an ADR. The patient was admitted with loss of consciousness due to respiratory failure. Tracheostomy was promptly performed under sedation with multiple general anesthetic agents. Immediately after tracheostomy, the patient communicated via eye-blinking without any notable abnormalities, just as before the procedure. However, the following day, he became unresponsive to verbal cues and exhibited a decreased level of consciousness, accompanied by tongue dyskinesia, deviation of both eyes to the left, and loss of visual tracking. The patient’s vital signs remained stable. Brain imaging and an electroencephalogram revealed no abnormalities. Treatment with midazolam produced initial improvement; however, due to a significant side effect of hypotension, the treatment was switched to oral diazepam. The patient’s condition gradually improved, and the medication was eventually discontinued without further ADR episodes.

Comparison of Hemodynamic Parameters Based on the Administration of Remimazolam or Sevoflurane in Patients under General Anesthesia in the Beach Chair Position: A Single-Blinded Randomized Controlled Trial.

Background: We aimed to evaluate whether the administration of remimazolam as a maintenance agent for general anesthesia affects the occurrence of hypotension compared with sevoflurane when switching to the beach chair position (BCP). Methods: We conducted a prospective randomized controlled trial from June 2023 to October 2023 in adult patients undergoing orthopedic surgery under general anesthesia in the BCP. A total of 78 participants were randomly allocated to the remimazolam (R) or sevoflurane (S) groups. The primary outcome was the incidence of hypotension that occurred immediately after switching to a BCP. The secondary outcomes included differences between the study groups in perioperative blood pressure (BP), heart rate (HR), endotracheal tube extubation time, postoperative complications, and hospital length of stay (LOS). Results: The incidence of hypotension immediately after switching to a BCP was significantly higher in the S group. The risk factors associated with hypotension included sevoflurane administration and a high baseline systolic BP. In the receiver operating characteristic curve analysis for the occurrence of hypotension after the transition to a BCP, the cutoff value for systolic BP was 142 mmHg. The perioperative BP and HR were higher in the R group at several timepoints. Postoperative endotracheal tube extubation time was shorter in the R group. There were no significant differences in the postoperative complications or hospital LOS between the two groups. Conclusions: Remimazolam should be considered as an anesthetic agent to prevent hypotension when switching to BCP, and hypotension may occur frequently in patients with high baseline BP.

Quality of Postoperative Recovery in Total Intravenous Anesthesia between Remimazolam and Propofol for Intraoperative Neurophysiological Monitoring: A Prospective Double-Blind Randomized Controlled Trial.

This study compared the overall postoperative recovery of patients who underwent total intravenous anesthesia with remimazolam or propofol, using the Quality of Recovery-15 questionnaire (QoR-15). Seventy-two patients who underwent spine surgery with intraoperative neurophysiological monitoring (IONM) were randomly categorized into the remimazolam group (group R) or propofol group (group P). On the first postoperative day, the QoR-15 scores for groups P and R were 114 and 112, respectively, indicating no significant difference (p = 0.691). Similarly, group-time interaction effects on QoR-15 scores were not significantly different. In the post-anesthesia care unit, the pain intensity at rest was notably higher in group P than in group R (3.0 [0.0] vs. 2.8 [0.5], respectively, p = 0.009). Although the intraoperative consumption of remifentanil was higher in group R (1452.4 µg vs. 2066.8 µg, respectively, p < 0.001), the intraoperative use of vasopressors was lower in group R (1705.6 µg vs. 286.1 µg, respectively, p < 0.001) compared to group P. Group R exhibited significantly lower variability in mean blood pressure over time compared to group P. Remimazolam was viewed as a promising intravenous agent for general anesthesia, showing potential to replace propofol in spine surgery with IONM, considering both recovery quality and intraoperative hemodynamic stability.

Exploring the Utility of remimazolam in cesarean sections under general anesthesia: A preliminary retrospective analysis and Implications for future study

BackgroundRemimazolam has recently been introduced as a maintenance agent for general anesthesia. However, the effect of remimazolam on peripartum prognosis has not been reported. Therefore, this study aimed to compare the effects of remimazolam and propofol for uterotonic drugs following cesarean section. MethodsThe electronic medical records of 51 adult women who underwent elective cesarean sections by single obstetrician under general anesthesia were collected. Participants were categorized into two groups: the propofol group and the remimazolam group. General anesthesia was maintained by continuous infusion of propofol or remimazolam after delivery. The number of uterotonic drugs administered during the cesarean section, the estimated blood loss (EBL), and length of hospital stay (LOS) after delivery were assessed. ResultsOf the 51 patients included in the study, 35 were in the propofol group and 16 in the remimazolam group. In the remimazolam group, five patients (31.3%, 5/16) received more uterotonics than the standard regimen. Conversely, in the propofol group, 19 patients (54.3%, 19/35) were injected with more uterotonics than the standard regimen. Logistic regression analysis showed that abnormal positioning of the placenta (P = 0.079) and not using remimazolam (P = 0.100) were the most relevant factors associated with the increased use of uterotonics. There was no significant difference in EBL between the two groups. The use of remimazolam was clinically relevant with a shorter LOS (P = 0.059). ConclusionsThe use of remimazolam as a maintenance agent did not result in significantly higher use of intrapartum uterotonics compared to the use of propofol. These results cannot exclude all adverse effects of remimazolam during cesarean delivery. Further randomized controlled trials must be conducted to obtain high-quality evidence.

Literature Review: Gambaran Monitoring Kedalaman Anestesi Pada Anestesi Umum

The term "depth of anesthesia" refers to the extent to which a general anesthetic agent anesthetizes the central nervous system with a specific concentration of force at the time the drug is administered. The depth level of anesthesia plays an important role in determining surgical complications, and it is very important to keep the depth level of anesthesia under control for the operation to be successful. The purpose of this study is to determine the Monitoring Picture of Anesthesia Depth in General Anesthesia. The literature search will be conducted between 2018 and 2023. The methodof journals and scientific articles contained in this study are national and international journals that have been accounted for their validity. Sources of information obtained from databases are Google Scholar, Science Direct, and PubMed. Anesthesia depth monitoring with the most popular modern technique in practice is the Bixpectral Index Score (BIS) monitor. Anesthesia depth monitoring using BIS is more accurate than traditional anesthesia depth monitoring. Objective assessment of the depth of sedation can use the BIS tool that provides the best prediction of the patient's degree of consciousness to] prevent the patient from waking up and remember actions, drug additions, and wake predictions more accurately by looking at changes in brain electrical activity depicted through EEG

Time to Wake Up! The Ongoing Search for General Anesthetic Reversal Agents.

How general anesthetics work remains a topic of ongoing study. A parallel field of research has sought to identify methods to reverse general anesthesia. Reversal agents could shorten patients' recovery time and potentially reduce the risk of postoperative complications. An incomplete understanding of the mechanisms of general anesthesia has hampered the pursuit for reversal agents. Nevertheless, the search for reversal agents has furthered understanding of the mechanisms underlying general anesthesia. The study of potential reversal agents has highlighted the importance of rigorous criteria to assess recovery from general anesthesia in animal models, and has helped identify key arousal systems (e.g., cholinergic, dopaminergic, and orexinergic systems) relevant to emergence from general anesthesia. Furthermore, the effects of reversal agents have been found to be inconsistent across different general anesthetics, revealing differences in mechanisms among these drugs. The presynapse and glia probably also contribute to general anesthesia recovery alongside postsynaptic receptors. The next stage in the search for reversal agents will have to consider alternate mechanisms encompassing the tripartite synapse.

General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain.

General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells. Oligodendrocytes perform essential roles in the central nervous system, including myelin sheath formation, axonal metabolism, and neuroplasticity regulation. They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation, differentiation, and apoptosis. Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes. These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways, but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function. In this review, we summarize the effects of general anesthetic agents on oligodendrocytes. We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.

Overexpression of SESN1 improves mitochondrial damage and mitophagy, a potential therapeutic strategy for cognitive dysfunction after anaesthesia.

Postoperative cognitive dysfunction (POCD) is a prevalent central nervous system complication predominantly observed in elderly patients. Sevoflurane, a general anaesthetic agent, has been implicated in the development of POCD, yet the underlying regulatory mechanisms potentially involving Sestrin1 (SESN1), a stress-responsive protein that plays a critical role in cellular homeostasis and protection against stress-induced damage, including oxidative stress and DNA damage, remain elusive. This study endeavoured to elucidate the impact of SESN1 on sevoflurane-induced cognitive impairment in rats. Employing a model in which SESN1 was transfected into SD male rats and cognitive dysfunction was induced by sevoflurane. The Morris Water Maze test was used for behavioural evaluation, Enzyme-Linked Immunosorbent Assay, Western blotting and immunofluorescence were applied to assess the influence of SESN1 on the inflammatory response and mitophagy in the rat hippocampus. The study further aimed to uncover the putative mechanism by which SESN1, through SIRT1, might modulate cognitive function. Concurrently, levels of malondialdehyde, superoxide dismutase and mitochondrially produced ATP within the rat hippocampus were quantified. Experimental outcomes suggested that SESN1 overexpression significantly mitigated the deleterious effects of sevoflurane anaesthesia, ameliorated neuroinflammation and inflammasome activation, modified mitochondrial function and facilitated mitophagy. Additionally, SESN1, via the activation of SIRT1, may suppress inflammasome activation and mitochondrial dysfunction. Collectively, these findings underscore SESN1's integral role in counteracting sevoflurane-induced cognitive impairment, impeding inflammasome activation, enhancing mitochondrial function and fostering mitophagy, which appear to be intricately linked to SESN1-mediated SIRT1 activation. SESN1 is a novel therapeutic target for POCD, potentially advancing neuroprotective strategies in clinical settings.

Cytochrome P450 2B6 and UDP-Glucuronosyltransferase Enzyme-Mediated Clearance of Ciprofol (HSK3486) in Humans: The Role of Hepatic and Extrahepatic Metabolism.

Ciprofol (HSK3486) is a novel intravenous agent for general anesthesia. In humans, HSK3486 mainly undergoes glucuronidation to form M4 [fraction of clearance (fCL): 62.6%], followed by the formation of monohydroxylated metabolites that further undergo glucuronidation and sulfation to produce M5-1, M5-2, M5-3, and M3 (summed fCL: 35.2%). However, the complete metabolic pathways of HSK3486 in humans remain unclear. In this study, by comparison with chemically synthesized reference standards, three monohydroxylated metabolites [M7-1, 4-hydroxylation with an unbound intrinsic clearance (CLint,u) of 2211 μl/min/mg; M7-2, ω-hydroxylation with a CLint,u of 600 μl/min/mg; and M7-3, (ω-1)-hydroxylation with a CLint,u of 78.4 μl/min/mg] were identified in human liver microsomes, and CYP2B6 primarily catalyzed their formation. In humans, M7-1 was shown to undergo glucuronidation at the 4-position and 1-position by multiple UDP-glucuronosyltransferases (UGTs) to produce M5-1 and M5-3, respectively, or was metabolized to M3 by cytosolic sulfotransferases. M7-2 was glucuronidated at the ω position by UGT1A9, 2B4, and 2B7 to form M5-2. UGT1A9 predominantly catalyzed the glucuronidation of HSK3486 (M4). The CLint,u values for M4 formation in human liver and kidney microsomes were 1028 and 3407 μl/min/mg, respectively. In vitro to in vivo extrapolation analysis suggested that renal glucuronidation contributed approximately 31.4% of the combined clearance. In addition to HSK3486 glucuronidation (M4), 4-hydroxylation (M7-1) was identified as another crucial oxidative metabolic pathway (fCL: 34.5%). Further attention should be paid to the impact of CYP2B6- and UGT1A9-mediated drug interactions and gene polymorphisms on the exposure and efficacy of HSK3486. SIGNIFICANCE STATEMENT: This research elucidates the major oxidative metabolic pathways of HSK3486 (the formation of three monohydroxylated metabolites: M7-1, M7-2, M7-3) as well as definitive structures and formation pathways of these monohydroxylated metabolites and their glucuronides or sulfate in humans. This research also identifies major metabolizing enzymes responsible for the glucuronidation (UGT1A9) and oxidation (CYP2B6) of HSK3486 and characterizes the mechanism of extrahepatic metabolism. The above information is helpful in guiding the safe use of HSK3486 in the clinic.

5-HT&lt;sub&gt;3&lt;/sub&gt; receptors in GtoPdb v.2023.3

The 5-HT3 receptor (nomenclature as agreed by the NC-IUPHAR Subcommittee on 5-Hydroxytryptamine (serotonin) receptors [69]) is a ligand-gated ion channel of the Cys-loop family that includes the zinc-activated channels, nicotinic acetylcholine, GABAA and strychnine-sensitive glycine receptors. The receptor exists as a pentamer of 4 transmembrane (TM) subunits that form an intrinsic cation selective channel [7]. Five human 5-HT3 receptor subunits have been cloned and homo-oligomeric assemblies of 5-HT3A and hetero-oligomeric assemblies of 5-HT3A and 5-HT3B subunits have been characterised in detail. The 5-HT3C (HTR3C, Q8WXA8), 5-HT3D (HTR3D, Q70Z44) and 5-HT3E (HTR3E, A5X5Y0) subunits [86, 125], like the 5-HT3B subunit, do not form functional homomers, but are reported to assemble with the 5-HT3A subunit to influence its functional expression rather than pharmacological profile [127, 66, 161]. 5-HT3A, -C, -D, and -E subunits also interact with the chaperone RIC-3 which predominantly enhances the surface expression of homomeric 5-HT3A receptor [161]. The co-expression of 5-HT3A and 5-HT3C-E subunits has been demonstrated in human colon [85]. A recombinant hetero-oligomeric 5-HT3AB receptor has been reported to contain two copies of the 5-HT3A subunit and three copies of the 5-HT3B subunit in the order B-B-A-B-A [9], but this is inconsistent with recent reports which show at least one A-A interface [99, 154]. The 5-HT3B subunit imparts distinctive biophysical properties upon hetero-oligomeric 5-HT3AB versus homo-oligomeric 5-HT3A recombinant receptors [35, 44, 59, 88, 143, 132, 82], influences the potency of channel blockers, but generally has only a modest effect upon the apparent affinity of agonists, or the affinity of antagonists ([19], but see [44, 33, 38]) which may be explained by the orthosteric binding site residing at an interface formed between 5-HT3A subunits [99, 154]. However, 5-HT3A and 5-HT3AB receptors differ in their allosteric regulation by some general anaesthetic agents, small alcohols and indoles [142, 139, 73]. The potential diversity of 5-HT3 receptors is increased by alternative splicing of the genes HTR3A and HTR3E [67, 21, 127, 126, 123]. In addition, the use of tissue-specific promoters driving expression from different transcriptional start sites has been reported for the HTR3A, HTR3B, HTR3D and HTR3E genes, which could result in 5-HT3 subunits harbouring different N-termini [156, 82, 123]. To date, inclusion of the 5-HT3A subunit appears imperative for 5-HT3 receptor function.

AS-IV enhances the antitumor effects of propofol in NSCLC cells by inhibiting autophagy.

Non-small cell lung cancer (NSCLC) is one of the most lethal malignant tumors. It has been shown that the general anesthetic agents, propofol and astragaloside IV (AS-IV) both exert antitumor effects in NSCLC. However, the effects of the combination of propofol with AS-IV in NSCLC remain unclear. Cell counting kit-8, and EdU and Transwell assays were performed to evaluate NSCLC cell viability, proliferation, and migration. Cell apoptosis and autophagy were observed by flow cytometric analysis and TUNEL and LC3 staining, respectively. AS-IV notably enhanced the anti-proliferative, pro-apoptotic, and anti-migratory properties of propofol in NSCLC cells. Moreover, AS-IV remarkably facilitated the anti-autophagy effect of propofol in NSCLC cells by downregulating LC3, Beclin 1, and ATG5. Significantly, the pro-apoptotic ability of the AS-IV/propofol combination in NSCLC cells was further enhanced by the autophagy inhibitor 3-MA, suggesting that autophagy plays a tumor-promoting role in NSCLC cells. Collectively, AS-IV could facilitate the antitumor abilities of propofol in NSCLC cells by inhibiting autophagy. These findings may be beneficial for future studies on the use of AS-IV and propofol for the treatment of NSCLC.

General anesthetic agents induce neurotoxicity through astrocytes.

Neuroscientists have recognized the importance of astrocytes in regulating neurological function and their influence on the release of glial transmitters. Few studies, however, have focused on the effects of general anesthetic agents on neuroglia or astrocytes. Astrocytes can also be an important target of general anesthetic agents as they exert not only sedative, analgesic, and amnesic effects but also mediate general anesthetic-induced neurotoxicity and postoperative cognitive dysfunction. Here, we analyzed recent advances in understanding the mechanism of general anesthetic agents on astrocytes, and found that exposure to general anesthetic agents will destroy the morphology and proliferation of astrocytes, in addition to acting on the receptors on their surface, which not only affect Ca2+ signaling, inhibit the release of brain-derived neurotrophic factor and lactate from astrocytes, but are even involved in the regulation of the pro- and anti-inflammatory processes of astrocytes. These would obviously affect the communication between astrocytes as well as between astrocytes and neighboring neurons, other neuroglia, and vascular cells. In this review, we summarize how general anesthetic agents act on neurons via astrocytes, and explore potential mechanisms of action of general anesthetic agents on the nervous system. We hope that this review will provide a new direction for mitigating the neurotoxicity of general anesthetic agents.

Determination of Sufentanil in Human Plasma Using Ultra-high Performance Liquid Chromatography Coupled with Tandem Mass Spectrometry (UPLC–MS/MS)

Background: Sufentanil, an opioid analgesic, is used as an induction agent for general anesthesia during surgery. Sufentanil is more active than other anesthetics and has a narrow therapeutic range. Therefore, a precise dosage regimen is necessary when administering sufentanil. Objective: This study aimed to develop a bioanalytical method for the determination of sufentanil within the sensitive concentration range more than that in a previous study utilizing protein precipitation (PP) and determine the plasma concentration of sufentanil. Methods: A method for quantitating sufentanil was developed using ultra–high performance liquid chromatography coupled with mass spectrometry (UPLC–MS/MS) and detection by electrospray ionization (ESI). The internal standard was sufentanil-d5. Chromatographic separation was performed using an Acquity UPLC HSS T3 column (50 × 2.1 mm, 1.8 μm) from Waters (Milford, MA, USA). Protein precipitation (PP) was used for sample preparation, and gradient elution was conducted using a mobile phase consisting of 1 mL of 2M ammonium acetate in 99% formic acid in 1 L of water or in 1 L of acetonitrile. The total run time for the analysis was 5 min, and the flow rate was 0.4 mL/min. Results: Standard curves were linear over ranges of 0.025–30 ng/mL for sufentanil with a correlation coefficient (r2) greater than 0.9998. The lower limit of quantification (LLOQ) was 0.025 ng/mL. The intra– and inter–day accuracies were 97.66%–108.8% and 101.25%–103.17%, respectively, and the precision did not exceed 15% for sufentanil. Conclusion: This study developed a validated, simple, sensitive, and convenient UPLC–MS/MS method for quantifying sufentanil in human plasma. This method was applied to determine sufentanil concentration in the plasma of patients undergoing surgery. The bioanalytical method using PP showed a sufficiently sensitive concentration range. This method could be applied to various pharmacokinetic studies of sufentanil.

Etomidate versus Propofol for Electroconvulsive Therapy in Patients with Major Depressive Disorders in Terms of Clinical Responses to Treatment: A Retrospective Analysis.

General anesthetic agents may be associated with the clinical efficacy of electroconvulsive therapy (ECT), as they may influence seizure quality and duration. Hence, a retrospective study was conducted to compare the clinical effects and seizure variables of etomidate and propofol during ECT. Patients treated with ECT under anesthesia with etomidate (n = 43) or propofol (n = 12) were retrospectively analyzed. Seizure variables (seizure duration, intensity, and threshold) and hemodynamic changes during ECT were assessed and recorded. Clinical responses to treatment were evaluated using the Clinical Global Impression scale and mood at discharge after the course of ECT. Adverse effects were also recorded. The demographic characteristics were similar between the two groups. There were no significant differences in the Clinical Global Impression scale scores, mood at discharge, and adverse effects between the two groups (p > 0.05); however, etomidate was associated with a significantly longer motor (42.0 vs. 23.65 s, p < 0.001) and electroencephalogram (51.8 vs. 33.5 s, p < 0.001) seizure duration than propofol. In conclusion, etomidate showed more favorable seizure profiles than propofol during ECT; however, both agents (etomidate and propofol) were associated with similar clinical efficacy profiles at discharge.

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

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

General Anaesthetic Agents and its Implication on the Cardiovascular System: A Systemic Review

Background: This review evaluates the possible cardiac side effects of general anesthetic agents upon usage. Cardiac as well as non-cardiac surgery may precipitate adverse events including ischaemia, diverse arrhythmias and reperfusion injury. Volatile and non-volatile anesthetic agents possess cardiovascular effects that can lead to depression of cardiac contractility, arterial pressure, ventricular resistance and reflex tachycardia. However, as not all studies have demonstrated improved outcomes, the risk for undesirable haemodynamic effects must be weighed against the possible benefits of using anaesthetic agents either pre-operatively, intra-operatively or post-operatively during both cardiac and non-cardiac surgeries as well as in patients with coronary artery disease. The halogenated agents all have similar circulatory effects as seen in young, healthy volunteers during maintenance anesthesia (Cahalan MK et al., 1991; Eis S &amp; Kramer J, 2022). The effects of anesthetics on the cardiovascular system have a complicated character, and almost all the anesthetic agents have a dose-related myocardial depression and decreases in heart rate and arterial pressure. During anesthesia, individual responses of patients against procedures such as induction, intubation, and surgical stimulation are influenced by many factors, including preoperatively used drugs, anesthesia type, preferred anesthetic agents, and the autonomic nervous system (Fee JPH et al., 1997, Pagel PS et al., 1991; Smith G et al., 2022).

Determination of Embryotoxic Effects of In Ovo Administered Propofol on Peripheral Blood Alpha Naphthyl Acetate Esterase and Acid Phosphatase-Positive Lymphocytes.

The aim of this study is to determine the possible embryotoxic effects of propofol, a general anaesthetic agent that is commonly used in clinical practice, on peripheral blood lymphocytes using enzyme histochemical techniques. For this purpose, 430 laying hen fertile eggs were used for this study. The eggs were divided into 5 groups as control, solvent-control (saline), 2.5 mg kg-1 propofol, 12.5 mg kg-1 propofol, and 37.5 mg kg-1 propofol, and injections were performed via the air sac just before the incubation. The peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios were determined on the hatching day. No statistically significant difference was found between both alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios of the control and solvent-control groups. However, when compared with the control and solvent-control groups, statistically significant decreases were observed in the peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios of the chicks from the propofol-injected groups. Besides, the difference between 2.5 mg kg-1 and 12.5 mg kg-1 propofol groups is not significant, whereas the difference between these 2 groups and the 37.5 mg kg-1 propofol group was statistically significant (P < .05). It was concluded that propofol given to fertilised chicken eggs just before incubation caused significant decreases in both the peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios.

Diagnostic Accuracy of Tympanometry for Diagnosis of Fluid the Middle Ears of Children with Otitis Media with Effusion staking Myringotomy as Gold Standard

Objective: To determine the diagnostic accuracy of tympanometry for diagnosing fluid in the middle ears of children with Otitis Media with Effusion taking myringotomy as a gold standard.&#x0D; Study Design: Cross-sectional study&#x0D; Place and Duration of Study: Department of ENT &amp; Head and Neck Surgery, Combined Military Hospital, Peshawar Pakistan, from Oct 2018 to Sep 2020.&#x0D; Methodology: A total of 201 patients who underwent tympanometry followed by myringotomy of aged between 3 to 12 years of either gender were included. All patients underwent tympanometry. After that, myringotomy was carried out through a radial incision in the anteroinferior quadrant using a general inhalational anaesthetic agent. The operative findings at myringotomy were recorded. The presence of fluid on intraoperative findings using myringotomy was considered positive for the presence of fluid in the middle ears of children.&#x0D; Results: The age range of the patients was from 3-12 years, with a mean age of 7.35±2.41 years. Of these 207 patients,133(64.18%) were males, and 74(35.82%) were females. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of tympanometry for diagnosis of fluid in the middle ears of children with Otitis Media with Effusion taking myringotomy as the gold standard was 85.7%, 86.3%, 89.4%, 81.7% and 85.9% respectively.&#x0D; Conclusion: This study concluded that the diagnostic accuracy of tympanometry for the diagnosis of fluid in the middle ears of children with Otitis Media with Effusion is quite high.