Anesthesia Emergence Research Articles

Malnutrition in emergency general surgery: a survey of National Emergency Laparotomy Audit Leads.

Patients who are malnourished and have emergency general surgery, such as a laparotomy, have worse outcomes than those who are not malnourished. It is paramount to identify these patients and minimise this risk. This study aimed to describe current practices in identifying malnutrition in patients undergoing a laparotomy, specifically focusing on screening, assessment, nutrition pathways and barriers encountered by clinicians. Following piloting and validity assessment, anaesthetic and surgical National Emergency Laparotomy Audit (NELA) Leads at hospitals across England and Wales were emailed an invitation to a survey. Responses were gathered using Qualtrics. Descriptive analysis and correlation with laparotomy volume and professional role were performed in SPSSv26. University of Sheffield ethical approval was obtained (UREC 046205). The results from the survey are reported according to the CHERRIES guidelines. The survey was completed by 166/289 NELA Leads from 117/167 hospitals (57.4% and 70.1% response rates, respectively). Participants reported low rates of nutritional screening (42/166; 25.3%) and assessment (26/166; 15.7%) for malnutrition preoperatively. More than one third of respondents (40.1%) had no awareness of local screening tools; indeed, the Malnutrition Universal Screening Tool (MUST) was used by approximately half of respondents (56.6%). Contrary to guidelines, NELA Leads report albumin levels continue to be used to determine malnutrition risk (73.5%; 122/166). Postoperative nutrition pathways were common (71.7%; 119/166). Reported barriers to nutritional screening and assessment included a lack of time, training and education, organisational support and ownership. Participants indicated nutrition risk is inadequately identified and is an important missing data item from NELA. There was no significant correlation with hospital laparotomy volume in relation to screening or assessment for malnutrition, the use of nutritional support pathways or organisational barriers. There was interprofessional agreement across a number of domains, although some differences did exist. Wide variation exists in the current practice of identifying malnutrition risk in NELA patients. Barriers include a lack of time, knowledge and ownership. Nutrition pathways that encompass the preoperative phase and incorporation of nutrition data in NELA may support improvements in care.

Prelimbic cortical pyramidal neurons to ventral tegmental area projections promotes arousal from sevoflurane anesthesia.

General anesthesia has been used in surgical procedures for approximately 180 years, yet the precise mechanism of anesthetic drugs remains elusive. There is significant anatomical connectivity between the ventral tegmental area (VTA) and the prelimbic cortex (PrL). Projections from VTA dopaminergic neurons (VTADA ) to the PrL play a role in the transition from sevoflurane anesthesia to arousal. It is still uncertain whether the prelimbic cortex pyramidal neuron (PrLPyr ) and its projections to VTA (PrLPyr -VTA) are involved in anesthesia-arousal regulation. We employed chemogenetics and optogenetics to selectively manipulate neuronal activity in the PrLPyr -VTA pathway. Electroencephalography spectra and burst-suppression ratios (BSR) were used to assess the depth of anesthesia. Furthermore, the loss or recovery of the righting reflex was monitored to indicate the induction or emergence time of general anesthesia. To elucidate the receptor mechanisms in the PrLPyr -VTA projection's impact on anesthesia and arousal, we microinjected NMDA receptor antagonists (MK-801) or AMPA receptor antagonists (NBQX) into the VTA. Our findings show that chemogenetic or optogenetic activation of PrLPyr neurons prolonged anesthesia induction and promoted emergence. Additionally, chemogenetic activation of the PrLPyr -VTA neural pathway delayed anesthesia induction and promoted anesthesia emergence. Likewise, optogenetic activation of the PrLPyr -VTA projections extended the induction time and facilitated emergence from sevoflurane anesthesia. Moreover, antagonizing NMDA receptors in the VTA attenuates the delayed anesthesia induction and promotes emergence caused by activating the PrLPyr -VTA projections. This study demonstrates that PrLPyr neurons and their projections to the VTA are involved in facilitating emergence from sevoflurane anesthesia, with the PrLPyr -VTA pathway exerting its effects through the activation of NMDA receptors within the VTA.

Effect of Remimazolam Supplementation on Propofol Requirements During Hysteroscopy: A Double-Blind, Dose-Response Study.

Propofol is commonly used for procedural sedation but may increase side effects in a dose-dependent manner. Remimazolam, an ultrashort-acting benzodiazepine, has been approved for procedural sedation but may delay awakening. This study tested the hypothesis that remimazolam as a supplement reduces effect-site propofol concentration (Ceprop) required to suppress response to cervical dilation in patients undergoing hysteroscopy. One hundred and fifty patients who were scheduled for hysteroscopy were randomized to receive 0, 0.05, 0.1, 0.15, or 0.2 mg·kg-1 intravenous remimazolam, followed by a bolus of sufentanil 0.15 μg⋅kg-1, and a target-controlled propofol infusion. The initial target Ceprop was 3.5 μg·mL-1 and was increased or decreased in subsequent patients by steps of 0.5 μg·mL-1 according to whether there was loss of response to cervical dilation in the previous patient. We used up-down sequential analysis to determine values of Ceprop that suppressed response to cervical dilation in 50% of patients (EC50). The EC50 of propofol for suppressing response to cervical dilation was lower in patients given 0.1 mg·kg-1 (2.08 [95% confidence interval, CI, 1.88-2.28] μg·mL-1), 0.15 mg⋅kg-1 (1.83 [1.56-2.10] μg·mL-1), and 0.2 mg⋅kg-1 (1.43 [1.27-1.58] μg·mL-1) remimazolam than those given 0 mg⋅kg-1 (3.67 [3.49-3.86] μg·mL-1) or 0.05 mg⋅kg-1 (3.47 [3.28-3.67] μg·mL-1) remimazolam (all were P < .005). Remimazolam at doses of 0.1, 0.15, and 0.2 mg·kg-1 decreased EC50 of propofol by 43.3% (95% CI, 41.3%-45.5%), 50.3% (48.0%-52.8%), and 61.2% (58.7%-63.8%), respectively, from baseline (remimazolam 0 mg⋅kg-1). Propofol consumption was lower in patients given 0.1 mg⋅kg-1 (4.15 [3.51-5.44] mg·kg-1), 0.15 mg⋅kg-1 (3.54 [3.16-4.46] mg·kg-1), and 0.2 mg⋅kg-1 (2.74 [1.73-4.01] mg·kg-1) remimazolam than those given 0 mg⋅kg-1 (6.09 [4.99-7.35] mg·kg-1) remimazolam (all were P < .005). Time to anesthesia emergence did not differ significantly among the 5 groups. For women undergoing hysteroscopic procedures, remimazolam at doses from 0.1 to 0.2 mg·kg-1 reduced the EC50 of propofol inhibiting response to cervical dilation and the total propofol requirement. Whether the combination could improve perioperative outcomes deserves further investigation.

Safety and Risk in Airway Management During Bariatric Air Medical Retrieval

ObjectiveBariatric anatomy and physiology present added clinical challenges to the provision of safe critical care and patient transport. LifeFlight Retrieval Medicine provides air medical retrieval services in Queensland, Australia, and performs over 6,000 retrieval missions annually using rotary wing, fixed wing, and ground ambulance platforms. MethodsBariatric patient retrievals were identified from the LifeFlight Retrieval Medicine electronic patient database. These cases were interrogated to quantify and describe adverse events during patient transport. ResultsOver the study period from July 2019 to December 2021 11,096 patient retrievals were completed. Of these patients, 816 (7.3%) had a body weight ≥ 120 kg (range, 120-246 kg; median = 146 kg). Bariatric patients were more likely to be male (70%) and to require critical care interventions than nonbariatric patients (25.9% vs. 19.9%). There was an absolute 1.5% increase of high-interest events during patient retrieval, corresponding to a 1.9-fold increased relative risk. Five hundred eleven of 11,096 patients were intubated by the retrieval team, and 61 of these weighed ≥ 120 kg. Bariatric patients undergoing intubation were of similar age and sex, weighed significantly more, had nonsignificant trends toward poorer airway visualization by Cormack-Lehane laryngoscopic grade, and tended toward reduced first-attempt success compared with nonbariatric patients. Rates of airway adverse events (AAEs) were significantly increased for the bariatric group (30/61, 49.2%) compared with the nonbariatric group (135/450, 30.0%) (χ2 likelihood ratio, P = .004). Postintubation desaturation was the most common AAE and was the only criterion significantly increased when comparing bariatric (26%) versus nonbariatric (12%) patients (χ2 likelihood ratio, P = .005). Using patient weight as a continuous variable, nominal logistic regression revealed a significant effect of increasing weight on AAEs (χ2 = 12.9, P = .0003) with a threshold of 105 kg providing an optimal 88% sensitivity for predicting AAEs. The odds of AAEs were increased significantly for those weighing 105 to 119 kg versus those weighing < 105 kg (odds ratio [OR] = 3.4; 95% confidence interval [CI], 1.6-7.5) and for those weighing ≥ 120 kg versus those weighing < 105 kg (OR = 2.5; 95% CI, 1.4-4.3). There was no difference between those weighing ≥ 120 kg versus those weighing 105 to 119 kg (OR = 0.73; 95% CI, 0.3-1.8). ConclusionAir medical retrieval of bariatric patients is safe despite an increased risk of adverse events. Strategies to optimize emergency anesthesia should be used to maximize safe intubation in bariatric patients.

Cardiorespiratory consequences of attenuated fentanyl and augmented rocuronium dosing during protocolised prehospital emergency anaesthesia at a regional air ambulance service: a retrospective study

BackgroundPre-Hospital Emergency Anaesthesia (PHEA) has undergone significant developments since its inception. However, optimal drug dosing remains a challenge for both medical and trauma patients. Many prehospital teams have adopted a drug regimen of 3 mcg/kg fentanyl, 2 mg/kg ketamine and 1 mg/kg rocuronium (‘3:2:1’). At Essex and Herts Air Ambulance Trust (EHAAT) a new standard dosing regimen was introduced in August 2021: 1 mcg/kg fentanyl, 2 mg/kg ketamine and 2 mg/kg rocuronium (up to a maximum dose of 150 mg) (‘1:2:2’). The aim of this study was to evaluate the cardiorespiratory consequences of a new attenuated fentanyl and augmented rocuronium dosing regimen.MethodsA retrospective study was conducted at EHAAT as a service evaluation. Anonymized records were reviewed from an electronic database to compare the original (‘3:2:1’) drug dosing regimen (December 2019-July 2021) and the new (‘1:2:2’) dosing regimen (September 2021-May 2023). The primary outcome was the incidence of absolute hypotension within ten minutes of induction. Secondary outcomes included immediate hypertension, immediate hypoxia and first pass success (FPS) rates.ResultsFollowing exclusions (n = 121), 720 PHEA cases were analysed (360 new vs. 360 original, no statistically significant difference in demographics). There was no difference in the rate of absolute hypotension (24.4% ‘1:2:2’ v 23.8% ‘3:2:1’, p = 0.93). In trauma patients, there was an increased first pass success (FPS) rate with the new regimen (95.1% v 86.5%, p = 0.01) and a reduced incidence of immediate hypoxia (7.9% v 14.8%, p = 0.05). There was no increase in immediate hypertensive episodes (22.7% vs. 24.2%, p = 0.73). No safety concerns were identified.ConclusionAn attenuated fentanyl and augmented rocuronium dosing regimen showed no difference in absolute hypotensive episodes in a mixed cohort of medical and trauma patients. In trauma patients, the new regimen was associated with an increased FPS rate and reduced episodes of immediate hypoxia. Further research is required to understand the impact of such drug dosing in the most critically ill and injured subpopulation.

A Single Center's Experience With Spinal Anesthesia for Pediatric Patients Undergoing Surgical Procedures

PurposeTo perform a single institution review of spinal instead of general anesthesia for pediatric patients undergoing surgical procedures. Spinal success rate, intraoperative complications, and postoperative outcomes including unplanned hospital admission and emergency department visits within seven days are reported. MethodsRetrospective chart review of pediatric patients who underwent spinal anesthesia for surgical procedures from 2016 until 2022. Data collected included patient demographics, procedure and anesthetic characteristics, intraoperative complications, unplanned admissions, and emergency department returns. ResultsThe study cohort included 1221 patients. Ninety-two percent of the patients tolerated their surgical procedure without requiring conversion to general anesthesia, and 78% of patients that had spinals placed successfully did not receive any sedation following lumbar puncture. The most common intraoperative event was systolic blood pressure below 60 mm Hg (14%), but no cases required administration of vasoactive agents, and no serious intraoperative adverse events were observed. Post-Anesthesia Care Unit Phase I was bypassed in 72% of cases with a median postoperative length of stay of 84 min. Forty-six patients returned to the emergency department following hospital discharge, but no returns were due to anesthetic concerns. ConclusionsSpinal anesthesia is a viable and versatile option for a diversity of pediatric surgical procedures. We noted a low incidence of intraoperative and postoperative complications. There remain numerous potential advantages of spinal anesthesia over general anesthesia in young pediatric patients particularly in the ambulatory setting. Level of EvidenceIV. Type of StudyRetrospective cohort treatment study.

The Median Effective Dose of Dexmedetomidine for the Inhibition of Emergence Delirium in Preschool Children Undergoing Tonsillectomy and/or Adenoidectomy: A Retrospective Dose-response Trial.

The incidence of emergence delirium (ED) is higher in preschool children undergoing tonsillectomy and/or adenoidectomy. The purpose of this study was to determine the median effective dose (ED50) of dexmedetomidine (DEX) for the inhibition of ED in preschool children by using probit regression analysis. A total of 140 anesthesia records were retrieved and divided into seven groups based on the infusion rate of DEX: .2, .25, .3, .35, .4, .45, and .5μg·kg-1·h-1. The Pediatric Anesthesia Emergence Delirium Scale (PAEDS) was used to assess ED in preschool children, and ED was defined as a PAEDS score ≥ 10. Probit regression analysis revealed that the ED50 and ED95 of DEX were .31μg·kg-1·h-1 (95% CI: .29-.35) and .48μg·kg-1·h-1 (95% CI: .44-.56), respectively. Probit(p) = -2.84 + 9.28 × ln (Dose), (χ2 = 1.925, P = .859). The PAEDS score was significantly increased in the ED group, and the rate of bradycardia was significantly decreased in the ED group compared with the without ED group (27.3% vs 54.1%, P = .02). DEX can effectively inhibit the ED in preschool children undergoing tonsillectomy and/or adenoidectomy, however, bradycardia was the main complication.

Haemodynamic response to pre-hospital emergency anaesthesia in trauma patients within an urban helicopter emergency medical service.

Pre-hospital emergency anaesthesia is routinely used in the care of severely injured patients by pre-hospital critical care services. Anaesthesia, intubation, and positive pressure ventilation may lead to haemodynamic instability. The aim of this study was to identify the frequency of new-onset haemodynamic instability after induction in trauma patients with a standardised drug regime. A retrospective database analysis was undertaken of all adult patients treated by a physician-led urban pre-hospital care service over a 6-year period. The primary outcome measure was the frequency of new haemodynamic instability following pre-hospital emergency anaesthesia. The association of patient characteristics and drug regimes with new haemodynamic instability was also analysed. A total of 1624 patients were included. New haemodynamic instability occurred in 231 patients (17.4%). Patients where a full-dose regime was administered were less likely to experience new haemodynamic instability than those who received a modified dose regime (9.7% vs 24.8%, p < 0.001). The use of modified drug regimes became more common over the study period (p < 0.001) but there was no change in the rates of pre-existing (p = 0.22), peri-/post-anaesthetic (p = 0.36), or new haemodynamic instability (p = 0.32). New haemodynamic instability within the first 30min following pre-hospital emergency anaesthesia in trauma patients is common despite reduction of sedative drug doses to minimise their haemodynamic impact. It is important to identify non-drug factors that may improve cardiovascular stability in this group to optimise the care received by these patients.

Methadone for Emergence Delirium in Ambulatory Pediatric Strabismus Surgery.

Background: Emergence delirium in children following strabismus surgery is a distressing and potentially dangerous condition and is likely attributable to visual disturbances, pain, and anesthetic gases. We explored whether a single intraoperative dose of methadone could reduce emergence delirium. Methods: Our study was an institutional review board-approved prospective, controlled, before-and-after investigation. Inclusion criteria were age <18 years and American Society of Anesthesiologists (ASA) classification 1 or 2. Patients were excluded for obesity, documented sleep apnea, significant neurologic disease, or inpatient status. Control group patients were recruited sequentially, and the anesthetic was performed per preference. The study group was recruited similarly and received an intravenous dose of methadone 0.15 mg/kg at induction. The primary outcome was peak score on the Pediatric Anesthesia Emergence Delirium (PAED) scale. Secondary outcomes included time to anesthetic emergence, postoperative pain scores, postanesthesia care unit (PACU) length of stay, and postdischarge respiratory complications. Results: Forty-nine control group and 55 study group patients were recruited. No significant differences were found between groups for age, sex, weight, ASA classification, or duration of surgery. The control group received more preoperative midazolam, intraoperative fentanyl, and intraoperative ketorolac. Compared to the control group, the study group had 42% and 85% reductions in peak and severe PAED scale scores, respectively, in the PACU and required less rescue pain medications. Anesthetic emergence time and length of stay were not different between the groups. No significant postoperative complications occurred. Conclusion: Emergence delirium following outpatient pediatric strabismus surgery was substantially mitigated by the use of intraoperative methadone without affecting PACU throughput. No significant complications occurred. Further study is warranted to corroborate routine use of this drug for emergence delirium.

Clinical Application of Bilateral Nasopharyngeal Airway in Painless Colonoscopy for Obese Patients.

This study aims to evaluate the safety and efficacy of using bilateral nasopharyngeal airways (NPA) during colonoscopic polypectomy performed under sedation anesthesia in obese patients. Ninety obese patients undergoing colonoscopic polypectomy under elective sedation anesthesia at Shanghai Shuguang Hospital were randomly allocated to two groups. Patients in group B had a nasopharyngeal airway inserted bilaterally after induction of anesthesia, whereas patients in group U had a nasopharyngeal airway inserted in only one nostril. Spontaneous breathing was maintained in both groups. The primary observation parameter was the incidence of oxygen saturation (SpO2) ≤ 92% during anesthesia, while secondary observation parameters included preoperative, intraoperative, and post-operative SpO2 levels, mean arterial pressure (MAP), heart rate (HR), dosage of propofol, duration of the operation, time to anesthesia recovery, need for emergency airway intervention, and occurrence of other adverse events. Hypoxia occurred in 5 out of 45 patients (11.1%) in group B, whereas it was observed in 14 out of 45 patients (31.1%) in group U (P < 0.05). Patients in group B exhibited higher SpO2 levels during and after surgery compared to those in group U (P<0.05). Furthermore, the decrease in intraoperative and post-operative SpO2 levels from baseline was significantly lower in group B compared to group U (P < 0.05). The number of emergency airway interventions, operation time, propofol dosage, and anesthesia recovery time were significantly lower in group B compared to group U (P<0.05). However, there were no significant differences in MAP, HR, or the incidence of adverse events between the two groups (P>0.05). The utilization of bilateral nasopharyngeal airway placement proves to be an effective strategy in decreasing the occurrence of hypoxia among obese patients undergoing colonoscopy under sedation anesthesia, thereby improving procedural safety.

Effect of Dexmedetomidine versus Propofol on Sevoflurane related Emergence Agitation in Paediatric Patients: A Randomised Clinical Study

Introduction: Postoperative Emergence Agitation (EA) is a troublesome side-effect of sevoflurane anaesthesia. Drugs like dexmedetomidine and propofol offer significant benefits in reducing the incidence and severity of sevoflurane-related postoperative EA in paediatric patients. Aim: To compare the efficacy of intravenous dexmedetomidine and propofol in reducing the incidence and severity of EA associated with sevoflurane anaesthesia in paediatric patients. Materials and Methods: A randomised clinical study was conducted on 140 patients, belonging to American Society of Anaesthesiologists Physical Status (ASA PS) classes I and II, aged between 2-6 years, undergoing infraumbilical surgery lasting more than one hour. The patients were divided into two equal groups receiving dexmedetomidine 0.3 μg/kg (Group SD) and propofol 1 mg/kg (Group SP) at the start of skin closure, administered over 10 minutes. The incidence of EA in the Post Anaesthesia Care Unit (PACU) was evaluated using the Watcha scale, and the severity of EA was assessed using the Paediatric Anaesthesia Emergence Delirium (PAED) scale. A Watcha score of 3 or 4 indicated the presence of EA, while a PAED score of ≥12 was deemed significant. Statistical analysis of the data was performed using International Business Machines (IBM) Statistical Package for Social Sciences (SPSS) version 22.0, with an Independent sample t-test for comparing normally distributed quantitative parameters, and the Chi-square test for comparing categorical outcomes between the study groups. Results: The mean age of the patients in group SD was 4.19±0.78 years, and in group SP was 4.03±0.71 years. Both study groups were found to be comparable in terms of patient characteristics such as age, sex, weight, and duration of surgery (p-value &gt;0.05). The incidence of postoperative EA, as measured by the Watcha scale, was higher in group SP compared to group SD upon arrival and up to 30 minutes in the PACU (p-value &lt;0.001). The severity of EA, assessed using the PAED score, was greater in group SP compared to group SD at 0, 5, 10,15 and 20 minutes in the PACU (p-value &lt;0.001). Conclusion: Dexmedetomidine 0.3 μg/kg was more effective than propofol 1 mg/kg in reducing the incidence and severity of EA associated with sevoflurane anaesthesia, with minimal haemodynamic effects and no clinically relevant severe adverse effects in both the groups. The significantly prolonged extubation times observed in the propofol group did not result in significantly longer stays in the PACU.

Does pain optimisation impact delirium outcomes in critically ill patients? A systematic review and meta-analysis protocol

BackgroundUntreated pain is associated with short-term and long-term consequences, including post-traumatic stress disorder and insomnia. Side effects of some analgesic medications include dysphoria, hallucinations and delirium. Therefore, both untreated pain...

Ciprofol in Children Undergoing Adenoidectomy and Adenotonsillectomy: A Retrospective Cohort Study.

Ciprofol is a novel anesthetic agent, its efficacy and safety had been verified and its clinical implementation has been expanded. However, the knowledge about ciprofol in children is meager. The aim of study is to evaluate the safety and effectiveness of ciprofol in general anesthesia in children undergoing adenoidectomy and adenotonsillectomy, compared with propofol. We retrospectively analyzed data of children who underwent adenoidectomy or adenotonsillectomy with general anesthesia from June to August 2023 to evaluate the safety and effectiveness of ciprofol. The primary outcomes included hemodynamic changes during induction and postoperative complications in post-anesthesia care unit. The secondary outcomes were extubation time, pediatric anesthesia emergence delirium (PAED) score. Meanwhile, subgroup analysis was performed based on age. 301 children met the inclusion criteria, 157 received ciprofol induction and 144 received propofol. Patient demographics and operation-related information were similar in the two groups. However, the dosage of dexmedetomidine in the propofol group was significantly higher than that of the ciprofol group (p=0.001). The trends of hemodynamic shift during induction and intubation were the same in the two groups. The PAED scores on post-extubation 10min and 20min were significantly reduced in the ciprofol group (p<0.001 and p=0.046). Moreover, in the ≤72 months and the >72 months subgroups, the scores were also significantly lower in the ciprofol group on post-extubation 10min. With the score of >10, the incidence of emergence delirium of the ciprofol group was significantly lower on post-extubation 10min and 20min in the population and the ≤72 months subgroups (p=0.03 and p=0.02). There were no obvious postoperative complications in both groups. Ciprofol exhibited advantageous characteristics in the induction of children, such as stable hemodynamics, a relatively lower incidence of postoperative delirium without apparent post-anesthesia complications. Ciprofol may emerge as a novel option for general anesthesia in pediatric patients.

Comparison of the Agitation-Reducing Effects of Esmolol and Lidocaine in Pediatric Strabismus Surgery: A Double-Blind, Randomized Clinical Study

Objective: Agitation is a common symptom in children undergoing surgery, especially when surgeries are performed under sevoflurane and when patients undergo strabismus surgery. Because agitation can increase the risk of falls and lacerations on surgical sites and can delay discharge from the recovery room, adopting measures to reduce the incidence of agitation is essential. This study aimed to compare the agitation-reducing effects of lidocaine and esmolol administered individually or as a combination.Methods: We included 80 patients scheduled to undergo strabismus surgery. Thiopental and sevoflurane were administered to induce general anesthesia. Group EL received lidocaine (2 mg/kg) right after the end of surgery and esmolol (0.5 mg/kg) immediately after recovery from anesthesia after turning the anesthetic gas off; group L received lidocaine at 2 mg/kg right after the end of surgery and did not receive esmolol, group E did not receive lidocaine at the end of the surgery but received esmolol at 0.5 mg/kg right after recovery from anesthesia, and group C received neither esmolol nor lidocaine. Agitation severity was assessed using the objective pain score, Pediatric Anesthesia Emergence Delirium Scale immediately after recovery from anesthesia and until discharge from the recovery room.Results: Groups L and EL showed significantly lower agitation than groups E and C right after recovery from anesthesia, right after arrival to the recovery room, and 10 minutes after arrival to the recovery room (P &lt; 0.05). Groups L and EL showed no differences in the reduction of the severity of agitation (P &gt; 0.05).Conclusion: Compared to the groups without lidocaine administration, groups L and EL, which received 2 mg/kg lidocaine, showed a higher level of reduction in agitation immediately after recovery from anesthesia and right after arrival to the recovery room (P &lt; 0.05).

Microglia facilitate and stabilize the response to general anesthesia via modulating the neuronal network in a brain region-specific manner

General anesthesia leads to a loss of consciousness and an unrousable state in patients. Although general anesthetics are widely used in clinical practice, their underlying mechanisms remain elusive. The potential involvement of nonneuronal cells is unknown. Microglia are important immune cells in the central nervous system (CNS) that play critical roles in CNS function and dysfunction. We unintentionally observed delayed anesthesia induction and early anesthesia emergence in microglia-depleted mice. We found that microglial depletion differentially regulates neuronal activities by suppressing the neuronal network of anesthesia-activated brain regions and activating emergence-activated brain regions. Thus, microglia facilitate and stabilize the anesthesia status. This influence is not mediated by dendritic spine plasticity. Instead, it relies on the activation of microglial P2Y12 and subsequent calcium influx, which facilitates the general anesthesia response. Together, we elucidate the regulatory role of microglia in general anesthesia, extending our knowledge of how nonneuronal cells modulate neuronal activities.

Microglia facilitate and stabilize the response to general anesthesia via modulating the neuronal network in a brain region-specific manner.

General anesthesia leads to a loss of consciousness and an unrousable state in patients. Although general anesthetics are widely used in clinical practice, their underlying mechanisms remain elusive. The potential involvement of nonneuronal cells is unknown. Microglia are important immune cells in the central nervous system (CNS) that play critical roles in CNS function and dysfunction. We unintentionally observed delayed anesthesia induction and early anesthesia emergence in microglia-depleted mice. We found that microglial depletion differentially regulates neuronal activities by suppressing the neuronal network of anesthesia-activated brain regions and activating emergence-activated brain regions. Thus, microglia facilitate and stabilize the anesthesia status. This influence is not mediated by dendritic spine plasticity. Instead, it relies on the activation of microglial P2Y12 and subsequent calcium influx, which facilitates the general anesthesia response. Together, we elucidate the regulatory role of microglia in general anesthesia, extending our knowledge of how nonneuronal cells modulate neuronal activities.

Pre-oxygenation using high-flow nasal oxygen versus tight facemask in trauma patients undergoing emergency anaesthesia.

Patients suffering from major traumatic injuries frequently require emergency anaesthesia. Due to often compromised physiology and the time-sensitive management, trauma patients may be more prone to desaturate during induction of anaesthesia. We hypothesised that pre-oxygenation using high-flow nasal oxygen would decrease the risk of desaturation during induction of anaesthesia in trauma patients and the study therefore aimed to compare the frequency of desaturation when pre-oxygenation was performed with high-flow nasal oxygen or a traditional facemask. This exploratory, prospective, before-and-after study was conducted at the Karolinska University Hospital, Sweden. Adult (≥18 years of age) patients suffering major traumatic injuries needing emergency anaesthesia were included around the clock. Patients were pre-oxygenated using a tight-fitting facemask during the first nine months of enrollment. High-flow nasal oxygen was then introduced as a method for pre-oxygenation of trauma patients. The primary outcome was the proportion of patients desaturating <93% during induction of anaesthesia, assessed from the start of pre-oxygenation until one minute after intubation. Secondary outcomes included perceived difficulty of pre-oxygenation among anaesthetists (assessed on a scale between 1 and 10) and safety outcomes, such as incidence of regurgitations and intracranial gas (assessed radiologically). Data from 96 patients were analysed. Facemask pre-oxygenation was performed in 66 patients, while 30 patients were pre-oxygenated with high-flow nasal oxygen. The most frequent trauma mechanisms were stabbing injuries (n = 34 (35%)) and fall injuries (n = 21 (22%)). There were no differences in patient characteristics between the groups. Eight (12%) versus three (10%) patients desaturated <93% in the facemask and high-flow nasal oxygen group respectively, OR 0.81 (95% CI 0.20-3.28), p = .76. Anaesthetists assessed pre-oxygenation using high-flow nasal oxygen as easier compared to facemask pre-oxygenation. No patient in any group showed signs of regurgitation. Among patients with facial or skull fractures requiring anaesthesia before radiology was performed, intracranial gas was seen in four (40%) patients pre-oxygenated with a facemask and in no patient pre-oxygenated with HFNO (p = .23). In this prospective study investigating trauma patients undergoing emergency anaesthesia, we could not see any difference in the number of patients desaturating when pre-oxygenation was performed with high-flow nasal oxygen compared to a tight-fitting facemask. Pre-oxygenation using high-flow nasal oxygen was assessed as easier compared to facemask pre-oxygenation.

Critical hypertension in trauma patients following prehospital emergency anaesthesia: a multi-centre retrospective observational study

BackgroundCritical hypertension in major trauma patients is associated with increased mortality. Prehospital emergency anaesthesia (PHEA) is performed for 10% of the most seriously injured patients. Optimising oxygenation, ventilation, and cerebral perfusion, whilst avoiding extreme haemodynamic fluctuations are the cornerstones of reducing secondary brain injury. The aim of this study was to report the differential determinants of post-PHEA critical hypertension in a large regional dataset of trauma patients across three Helicopter Emergency Medical Service (HEMS) organisations.MethodsA multi-centre retrospective observational study of consecutive adult trauma patients undergoing PHEA across three HEMS in the United Kingdom; 2015–2022. Critical hypertension was defined as a new systolic blood pressure (SBP) > 180mmHg within 10 min of induction of anaesthesia, or > 10% increase if the baseline SBP was > 180mmHg prior to induction. Purposeful logistical regression was used to explore variables associated with post-PHEA critical hypertension in a multivariable model. Data are reported as number (percentage), and odds ratio (OR) with 95% confidence interval (95%CI).Results30,744 patients were attended by HEMS during the study period; 2161 received PHEA and 1355 patients were included in the final analysis. 161 (11.9%) patients had one or more new episode(s) of critical hypertension ≤ 10 min post-PHEA. Increasing age (compared with 16–34 years): 35–54 years (OR 1.76, 95%CI 1.03–3.06); 55–74 years (OR 2.00, 95%CI 1.19–3.44); ≥75 years (OR 2.38, 95%CI 1.31–4.35), pre-PHEA Glasgow Coma Scale (GCS) motor score four (OR 2.17, 95%CI 1.19–4.01) and five (OR 2.82, 95%CI 1.60–7.09), patients with a pre-PHEA SBP > 140mmHg (OR 6.72, 95%CI 4.38–10.54), and more than one intubation attempt (OR 1.75, 95%CI 1.01–2.96) were associated with post-PHEA critical hypertension.ConclusionDelivery of PHEA to seriously injured trauma patients risks haemodynamic fluctuation. In adult trauma patients undergoing PHEA, 11.9% of patients experienced post-PHEA critical hypertension. Increasing age, pre-PHEA GCS motor score four and five, patients with a pre-PHEA SBP > 140mmHg, and more than intubation attempt were independently associated with post-PHEA critical hypertension.

Comparison of post-auricular and frontal bispectral index values obtained during renal surgeries

BackgroundThe bispectral index (BIS) monitor is one of the EEG-derived monitoring techniques and well-established devices used to measure the depth of anesthesia. This study aimed to assess the agreement of BIS values based on the positions of either post-auricular or frontal sensors in individual patients undergoing renal surgeries while lateral positions at various stages of anesthesia.Patients and methods12 patients older than 18 years, ASA I-III patients scheduled for elective renal operations, two BIS were placed on each patient, one on each side of the post-auricular region and one across the forehead, and each sensor was connected to a different BIS monitor. We gathered three pieces of data at each of the six-time points: BIS score, signal quality index (SQI) score calculating the signal’s strength and electromyography (EMG) score: before the onset of anesthesia (awake) when the eyelash reflex is lost (LOC), after intubation (intubation), following the initial surgical incision, each 30 min throughout the procedure (maintenance), and at the moment the patient’s eyes open naturally after waking up from anesthesia (emergence).ResultsThe overall BIS value at the frontal position was significantly higher than the post-auricular position (52.5 ± 22.2 and 52.1 ± 22.1, respectively, P = 0.010). On the other hand, the BIS value was comparable between the frontal and post-auricular positions at LOC, intubation, 60, 120, and 80 min and at emergence. A strong link between the two sensor positions, as indicated by the correlation coefficient (r = 0.607, P < 0.001), and the Bland-Altman analysis revealed a small mean difference (-1.8) and a low (9.0/- 12.5) limit of agreement, with just 4.3% of the readings falling outside of it during the anesthetic maintenance period.ConclusionAcceptable variation in BIS data was observed when obtained from the two different sensor positions for clinical usage. The post-auricular BIS sensor system may be a suitable substitute for an impractical frontal setup.Protocol RegistrationThe study was registered in clinicaltrials.gov on 11/07/2022 (trial registration number: NCT05451823).

Substance-dependent EEG during recovery from anesthesia and optimization of monitoring

The electroencephalographic (EEG) activity during anesthesia emergence contains information about the risk for a patient to experience postoperative delirium, but the EEG dynamics during emergence challenge monitoring approaches. Substance-specific emergence characteristics may additionally limit the reliability of commonly used processed EEG indices during emergence. This study aims to analyze the dynamics of different EEG indices during anesthesia emergence that was maintained with different anesthetic regimens. We used the EEG of 45 patients under general anesthesia from the emergence period. Fifteen patients per group received sevoflurane, isoflurane (+ sufentanil) or propofol (+ remifentanil) anesthesia. One channel EEG and the bispectral index (BIS A-1000) were recorded during the study. We replayed the EEG back to the Conox, Entropy Module, and the BIS Vista to evaluate and compare the index behavior. The volatile anesthetics induced significantly higher EEG frequencies, causing higher indices (AUC > 0.7) over most parts of emergence compared to propofol. The median duration of “awake” indices (i.e., > 80) before the return of responsiveness (RoR) was significantly longer for the volatile anesthetics (p < 0.001). The different indices correlated well under volatile anesthesia (rs > 0.6), with SE having the weakest correlation. For propofol, the correlation was lower (rs < 0.6). SE was significantly higher than BIS and, under propofol anesthesia, qCON. Systematic differences of EEG-based indices depend on the drugs and devices used. Thus, to avoid early awareness or anesthesia overdose using an EEG-based index during emergence, the anesthetic regimen, the monitor used, and the raw EEG trace should be considered for interpretation before making clinical decisions.