Pub Date : 2024-09-17DOI: 10.1101/2024.09.16.24313766
Lachlan D Barnes, Luke E Hallum, Xavier CE Vrijdag
Introduction: Divers often increase their fraction of inspired oxygen (FiO2) to decrease their risk of decompression sickness. However, breathing concentrated oxygen can cause hyperoxia, and central nervous system oxygen toxicity (CNS-OT). This study aims to review the literature describing hyperoxic ventilation's effect on the electroencephalogram (EEG), thus exploring the potential for real-time detection of impending CNS-OT seizure. Methods: We searched Medline, Embase, Scopus, and Web of Science for articles that reported EEG measures accompanying hyperoxic ventilation (FiO2 = 1.0) in healthy participants. We included peer-reviewed journal articles, books, and government reports with no language or date restrictions. Randomised controlled trials and cross-over studies were included; case reports were excluded. We used the Newcastle-Ottawa scale to evaluate evidence quality. Results: Our search strategy returned 1025 unique abstracts; we analysed the full text of 40 articles; 22 articles (16 studies) were included for review. Study cohorts were typically small, and comprised of male non-divers. We discovered a variety of EEG analysis methods: studies performed spectral analysis (n = 12), the analysis of sensory-evoked potentials (n = 4), connectivity/complexity analysis (n = 3), source localization (n = 1), and expert qualitative analyses (n = 4). Studies of severe exposures (long duration at hyperbaric pressure) typically reported qualitative measures, and studies of mild exposures typically reported quantitative measures. Conclusions: There is a need for a large randomised controlled trial (RCT) reporting quantitative measures to better understand hyperoxic ventilation's effect on EEG, thus enabling the development of real-time monitoring of CNS-OT risk.
{"title":"Electroencephalographic (EEG) Changes Accompanying Normal Breathing of Concentrated Oxygen (Hyperoxic Ventilation) by Healthy Adults: A Systematic Review","authors":"Lachlan D Barnes, Luke E Hallum, Xavier CE Vrijdag","doi":"10.1101/2024.09.16.24313766","DOIUrl":"https://doi.org/10.1101/2024.09.16.24313766","url":null,"abstract":"<strong>Introduction:</strong> Divers often increase their fraction of inspired oxygen (FiO<sub>2</sub>) to decrease their risk of decompression sickness. However, breathing concentrated oxygen can cause hyperoxia, and central nervous system oxygen toxicity (CNS-OT). This study aims to review the literature describing hyperoxic ventilation's effect on the electroencephalogram (EEG), thus exploring the potential for real-time detection of impending CNS-OT seizure. <strong>Methods:</strong> We searched Medline, Embase, Scopus, and Web of Science for articles that reported EEG measures accompanying hyperoxic ventilation (FiO<sub>2</sub> = 1.0) in healthy participants. We included peer-reviewed journal articles, books, and government reports with no language or date restrictions. Randomised controlled trials and cross-over studies were included; case reports were excluded. We used the Newcastle-Ottawa scale to evaluate evidence quality. <strong>Results:</strong> Our search strategy returned 1025 unique abstracts; we analysed the full text of 40 articles; 22 articles (16 studies) were included for review. Study cohorts were typically small, and comprised of male non-divers. We discovered a variety of EEG analysis methods: studies performed spectral analysis (n = 12), the analysis of sensory-evoked potentials (n = 4), connectivity/complexity analysis (n = 3), source localization (n = 1), and expert qualitative analyses (n = 4). Studies of severe exposures (long duration at hyperbaric pressure) typically reported qualitative measures, and studies of mild exposures typically reported quantitative measures.\u0000<strong>Conclusions:</strong> There is a need for a large randomised controlled trial (RCT) reporting quantitative measures to better understand hyperoxic ventilation's effect on EEG, thus enabling the development of real-time monitoring of CNS-OT risk.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-28DOI: 10.1101/2024.08.27.24312675
Xing Lu, Junhui Zhou, Xi Li, Jie Gao, Siqing Liu, Wei Zhong, Gaoyuan Xi, Yingchun Guo, Hongdang Xu
Chronic post-thoracotomy pain is a common complication that affects 20% to 60% of patients who undergo surgery for lung cancer. The persistent pain affects quality of life and satisfaction with surgery. Intravenous paracetamol and mannitol, known to have analgesic and antipyretic properties, may help relieve moderate-to-severe post-operative pain. This trial aims to assess their effectiveness and safety in managing chronic post-thoracotomy pain in patients with lung cancer. This prospective double-blind randomized controlled clinical trial will be conducted at a single center. A total of 856 patients who will undergo thoracoscopic radical surgery for lung cancer will be enrolled and randomly assigned to test (intravenous paracetamol and mannitol) and control (intravenous normal saline) groups in a 1:1 ratio (428 patients in each group). Efficacy will be evaluated in terms of the incidence of chronic post-thoracotomy pain at 3 months (primary outcome). Secondary outcomes will include the dosage of propofol and remifentanil, numerical rating scale pain scores, number of times the patient-controlled intravenous analgesia button is pressed, occurrence of post-operative nausea and vomiting and respiratory depression, time to first flatus and ambulation after surgery, length of hospital stay, surgeon and patient satisfaction, and incidence of chronic post-thoracotomy pain at 6 and 12 months after surgery. Quality of daily life will be evaluated at 3, 6, and 12 months after surgery. Intention-to-treat analysis will also be conducted. The research protocol has been reviewed and approved by the Medical Thesis Committee of Henan Provincial Chest Hospital and Chest Hospital of Zhengzhou University on April 29, 2023 (reference: [2023] approval number: [04-06]). The results of this trial will be communicated to the participants and subsequently submitted for publication in peer-reviewed journals for wider dissemination. The study has been registered in the Chinese Clinical Trial Registry on June 27, 2023 (registration number: ChiCTR2300072869, available at https://www.chictr.org.cn/). The protocol version number is Version 1.1, dated August 20, 2023.
{"title":"Efficacy of intravenous paracetamol and mannitol in managing chronic post-thoracotomy pain in patients with lung cancer: Study protocol for a single center prospective randomized double-blind controlled trial","authors":"Xing Lu, Junhui Zhou, Xi Li, Jie Gao, Siqing Liu, Wei Zhong, Gaoyuan Xi, Yingchun Guo, Hongdang Xu","doi":"10.1101/2024.08.27.24312675","DOIUrl":"https://doi.org/10.1101/2024.08.27.24312675","url":null,"abstract":"Chronic post-thoracotomy pain is a common complication that affects 20% to 60% of patients who undergo surgery for lung cancer. The persistent pain affects quality of life and satisfaction with surgery. Intravenous paracetamol and mannitol, known to have analgesic and antipyretic properties, may help relieve moderate-to-severe post-operative pain. This trial aims to assess their effectiveness and safety in managing chronic post-thoracotomy pain in patients with lung cancer. This prospective double-blind randomized controlled clinical trial will be conducted at a single center. A total of 856 patients who will undergo thoracoscopic radical surgery for lung cancer will be enrolled and randomly assigned to test (intravenous paracetamol and mannitol) and control (intravenous normal saline) groups in a 1:1 ratio (428 patients in each group). Efficacy will be evaluated in terms of the incidence of chronic post-thoracotomy pain at 3 months (primary outcome). Secondary outcomes will include the dosage of propofol and remifentanil, numerical rating scale pain scores, number of times the patient-controlled intravenous analgesia button is pressed, occurrence of post-operative nausea and vomiting and respiratory depression, time to first flatus and ambulation after surgery, length of hospital stay, surgeon and patient satisfaction, and incidence of chronic post-thoracotomy pain at 6 and 12 months after surgery. Quality of daily life will be evaluated at 3, 6, and 12 months after surgery. Intention-to-treat analysis will also be conducted. The research protocol has been reviewed and approved by the Medical Thesis Committee of Henan Provincial Chest Hospital and Chest Hospital of Zhengzhou University on April 29, 2023 (reference: [2023] approval number: [04-06]). The results of this trial will be communicated to the participants and subsequently submitted for publication in peer-reviewed journals for wider dissemination. The study has been registered in the Chinese Clinical Trial Registry on June 27, 2023 (registration number: ChiCTR2300072869, available at https://www.chictr.org.cn/<span>).</span> The protocol version number is Version 1.1, dated August 20, 2023.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-22DOI: 10.1101/2024.08.22.24312356
Yan Weng, Ziqi Shang, Yan Wang, Xiaojuan Liu, Yuling Tang, Hua Zhang, Chunmei Wu, Wenjie Mao, Qing Zhong
Background Intermittent Pringle Manipulation (IPM) is among the most common methods used for controlling blood loss during hepatectomy. Ischaemia–reperfusion injury has also been associated with IPM. Ischaemic injury exposes the liver cells to hypoxia, adenosine triphosphate depletion, pH changes, and cellular metabolic stress, all of which can lead to cell damage and death. Reperfusion injury is caused by microcirculatory dysfunction, hypoxia, oxidative stress, and apoptosis. The pathophysiological mechanism of ischaemia-reperfusion injury is hyperkalaemia. Hyperkalaemia is closely related to the electrophysiological activity of the myocardium. Acute hyperkalaemia is associated with life-threatening ventricular arrhythmia and sudden cardiac arrest. Therefore, it is necessary to observe changes in patient serum potassium concentrations during IPM to provide a reference for developing a secure anaesthesia management approach. Methods and analysis This was a single-centre, open, non-interventional, self-controlled study. All eligible consecutive patients were recruited from a regional medical centre and scheduled for elective hepatectomy. There was no control group; all participants were continuously enrolled from 1 September 2023 to 31 August 2024. The primary outcome was the perioperative serum potassium concentration during IPM. Secondary outcomes included perioperative electrocardiogram changes, lactic acid status, postoperative serum potassium concentration, alanine amine transferase, and aspartate amine transferase peaks, adverse events, serious adverse events, and postoperative hospital stay. These parameters were statistically compared. Subgroup analysis will be performed according to liver disease type and duration of IPM. Discussion Our finding will provide a reference for developing a secure anaesthesia management approach for anesthesiologists. Ethics and dissemination The Biomedical Ethics Review Committee of the People’s Hospital of Jianyang City approved the study protocol (ethics reference: JY202383). All relevant ethical guidelines were followed in this study. The findings will be disseminated in peer-reviewed journals, publicly available reports to be published online, and academic conferences.
{"title":"Effect of intermittent pringle manipulation on serum potassium concentration during laparoscopic hepatectomy: a self-controlled study protocol","authors":"Yan Weng, Ziqi Shang, Yan Wang, Xiaojuan Liu, Yuling Tang, Hua Zhang, Chunmei Wu, Wenjie Mao, Qing Zhong","doi":"10.1101/2024.08.22.24312356","DOIUrl":"https://doi.org/10.1101/2024.08.22.24312356","url":null,"abstract":"Background\u0000Intermittent Pringle Manipulation (IPM) is among the most common methods used for controlling blood loss during hepatectomy. Ischaemia–reperfusion injury has also been associated with IPM. Ischaemic injury exposes the liver cells to hypoxia, adenosine triphosphate depletion, pH changes, and cellular metabolic stress, all of which can lead to cell damage and death. Reperfusion injury is caused by microcirculatory dysfunction, hypoxia, oxidative stress, and apoptosis. The pathophysiological mechanism of ischaemia-reperfusion injury is hyperkalaemia. Hyperkalaemia is closely related to the electrophysiological activity of the myocardium. Acute hyperkalaemia is associated with life-threatening ventricular arrhythmia and sudden cardiac arrest. Therefore, it is necessary to observe changes in patient serum potassium concentrations during IPM to provide a reference for developing a secure anaesthesia management approach.\u0000Methods and analysis\u0000This was a single-centre, open, non-interventional, self-controlled study. All eligible consecutive patients were recruited from a regional medical centre and scheduled for elective hepatectomy. There was no control group; all participants were continuously enrolled from 1 September 2023 to 31 August 2024. The primary outcome was the perioperative serum potassium concentration during IPM. Secondary outcomes included perioperative electrocardiogram changes, lactic acid status, postoperative serum potassium concentration, alanine amine transferase, and aspartate amine transferase peaks, adverse events, serious adverse events, and postoperative hospital stay. These parameters were statistically compared. Subgroup analysis will be performed according to liver disease type and duration of IPM.\u0000Discussion\u0000Our finding will provide a reference for developing a secure anaesthesia management approach for anesthesiologists.\u0000Ethics and dissemination\u0000The Biomedical Ethics Review Committee of the People’s Hospital of Jianyang City approved the study protocol (ethics reference: JY202383). All relevant ethical guidelines were followed in this study. The findings will be disseminated in peer-reviewed journals, publicly available reports to be published online, and academic conferences.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-26DOI: 10.1101/2024.07.25.24310977
Joohyun Lee, Ju-Won Roh, Kyung-Hee Han, Min-Jeong Kim, Young Jeong Na, Bo Seong Yoon, Jee Young Lee
ABSTRACT Introduction: Reducing blood pressure fluctuations during surgery is a significant goal for anesthesiologists. Acupuncture may be a noninvasive intervention to reduce blood pressure fluctuations but has not yet been studied. This study aims to determine whether acupuncture can be used to reduce blood pressure fluctuations during surgery, especially in the early stages. Methods and analysis: This is a prospective, single-center, randomized controlled clinical trial with a parallel-group design. Thirty adult patients scheduled to undergo total laparoscopic hysterectomy are eligible. Participants who consent will be randomly assigned in a 1:1 ratio to the acupuncture or placebo group. They will be followed up for at least 14 days to assess the safety of the intervention, general anesthesia, and surgery. We will compare the differences between the highest and lowest mean blood pressures from anesthesia induction to the post incision period as the primary endpoint. As secondary outcomes, systolic, diastolic, and mean blood pressures will be compared at each predetermined time point. Incidence of hypotension, hypertension, tachycardia, and bradycardia will be counted separately. The use of remifentanil at the early stage of surgery, the rate of surgical discontinuation, and the length of hospital stay will be assessed as surrogate indicators of stable general anesthesia and surgical procedures. For patient reported outcomes, Spielbergers State Trait Anxiety Inventory and EuroQoL 5 Dimensions 5 Levels will evaluate the change in anxiety and overall quality of life. Another non pharmacological intervention may contribute to surgery by maintaining blood pressure fluctuations within a stable range during the early postoperative period. Ethics and dissemination: The study will be conducted in accordance with the Declaration of Helsinki, and approved by the Institutional Review Board of CHA Ilsan Medical Center (ICHA 2022 11 010, date of approval 2023 01 03). This study was registered at Clinicaltrials.gov (registration identifier: NCT05720884) and CRiS (registration identifier: KCT0009149). The publication is scheduled for December 2025. Data deposition is scheduled to occur.
{"title":"Rationale of acupuncture for stabilizing blood pressure fluctuation during total laparoscopic hysterectomy (ASBP): a parallel grouped, randomized clinical trial","authors":"Joohyun Lee, Ju-Won Roh, Kyung-Hee Han, Min-Jeong Kim, Young Jeong Na, Bo Seong Yoon, Jee Young Lee","doi":"10.1101/2024.07.25.24310977","DOIUrl":"https://doi.org/10.1101/2024.07.25.24310977","url":null,"abstract":"ABSTRACT Introduction: Reducing blood pressure fluctuations during surgery is a significant goal for anesthesiologists. Acupuncture may be a noninvasive intervention to reduce blood pressure fluctuations but has not yet been studied. This study aims to determine whether acupuncture can be used to reduce blood pressure fluctuations during surgery, especially in the early stages. Methods and analysis: This is a prospective, single-center, randomized controlled clinical trial with a parallel-group design. Thirty adult patients scheduled to undergo total laparoscopic hysterectomy are eligible. Participants who consent will be randomly assigned in a 1:1 ratio to the acupuncture or placebo group. They will be followed up for at least 14 days to assess the safety of the intervention, general anesthesia, and surgery. We will compare the differences between the highest and lowest mean blood pressures from anesthesia induction to the post incision period as the primary endpoint. As secondary outcomes, systolic, diastolic, and mean blood pressures will be compared at each predetermined time point. Incidence of hypotension, hypertension, tachycardia, and bradycardia will be counted separately. The use of remifentanil at the early stage of surgery, the rate of surgical discontinuation, and the length of hospital stay will be assessed as surrogate indicators of stable general anesthesia and surgical procedures. For patient reported outcomes, Spielbergers State Trait Anxiety Inventory and EuroQoL 5 Dimensions 5 Levels will evaluate the change in anxiety and overall quality of life. Another non pharmacological intervention may contribute to surgery by maintaining blood pressure fluctuations within a stable range during the early postoperative period.\u0000Ethics and dissemination: The study will be conducted in accordance with the Declaration of Helsinki, and approved by the Institutional Review Board of CHA Ilsan Medical Center (ICHA 2022 11 010, date of approval 2023 01 03). This study was registered at Clinicaltrials.gov (registration identifier: NCT05720884) and CRiS (registration identifier: KCT0009149). The publication is scheduled for December 2025. Data deposition is scheduled to occur.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141772895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-24DOI: 10.1101/2024.06.22.24308393
Dorra Nouri, Fatma Ezzahra Nouri, Aicha Rabai
Regional anesthesia (RA) is increasingly used in intensive care in Tunisia, but challenges persist to ensure optimal practice. We conducted a multicenter study involving post-operative and polyvalent intensive care units, both private and public. Resident physicians(44.7%) are sensitized to quality of care, but gaps remain. Attending physicians (63.3%) often report the absence of pain management committees (PMCs) and written protocols for RA. The majority express a need for continuous training, particularly on RA. High-fidelity simulation is the preferred format for learning. RA is commonly used in intensive care (97.2%), mainly epidural (76.4%) and femoral nerve blocks (54.9%). Ultrasound is widely preferred for guiding procedures (77.5%). The main areas of RA application are thoracic (94.4%) and limb trauma (64.8%). The ANI is the preferred pain monitoring tool (49.3%). Improving training and infrastructure is necessary for optimal RA practice in intensive care in Tunisia.
在突尼斯，区域麻醉（RA）越来越多地用于重症监护，但要确保最佳实践仍面临挑战。我们开展了一项多中心研究，涉及术后和多价重症监护病房，既有私立病房也有公立病房。住院医生（44.7%）对护理质量很敏感，但仍存在差距。主治医师（63.3%）经常反映缺乏疼痛管理委员会（PMC）和针对 RA 的书面协议。大多数医生表示需要持续培训，尤其是关于疼痛治疗的培训。高仿真模拟是首选的学习形式。RA通常用于重症监护（97.2%），主要是硬膜外（76.4%）和股神经阻滞（54.9%）。超声是引导手术的首选（77.5%）。RA的主要应用领域是胸部（94.4%）和四肢创伤（64.8%）。ANI 是首选的疼痛监测工具（49.3%）。要在突尼斯的重症监护中实现最佳的 RA 实践，就必须改善培训和基础设施。
{"title":"Regional Anesthesia in Intensive Care: An Overview in Tunisia","authors":"Dorra Nouri, Fatma Ezzahra Nouri, Aicha Rabai","doi":"10.1101/2024.06.22.24308393","DOIUrl":"https://doi.org/10.1101/2024.06.22.24308393","url":null,"abstract":"Regional anesthesia (RA) is increasingly used in intensive care in Tunisia, but challenges persist to ensure optimal practice. We conducted a multicenter study involving post-operative and polyvalent intensive care units, both private and public. Resident physicians(44.7%) are sensitized to quality of care, but gaps remain. Attending physicians (63.3%) often report the absence of pain management committees (PMCs) and written protocols for RA. The majority express a need for continuous training, particularly on RA. High-fidelity simulation is the preferred format for learning. RA is commonly used in intensive care (97.2%), mainly epidural (76.4%) and femoral nerve blocks (54.9%). Ultrasound is widely preferred for guiding procedures (77.5%). The main areas of RA application are thoracic (94.4%) and limb trauma (64.8%). The ANI is the preferred pain monitoring tool (49.3%). Improving training and infrastructure is necessary for optimal RA practice in intensive care in Tunisia.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141510701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Physiochemical properties of levobupivacaine and bupivacaine are identical, but pharmacokinetic and pharmacodynamics properties differ due to stereoselective interactions at the molecular sites of action. An evaluation of nerve block characteristicsis essential for optimal clinical application. This study compared the sensory blocking characteristics of levobupivacaine to bupivacaine in humans and model animals. Levobupivacaine and bupivacaine were compared for sensory block efficacy using a randomized, double-blinded, crossover study design. Eighteen healthy volunteers were randomized to receive levobupivacaine or bupivacaine by subcutaneous injection into the forearm, followed by the other drug 1 week later with injection order counterbalanced across subjects. Tactile detection and mechanical pain thresholds were determined using von Frey hairs and thermal pain threshold using a thermal stimulator. Effects of levobupivacaine and bupivacaine, on the spiking activity of spinal dorsal horn (SDH) neurons evoked by innocuous or noxious stimuli were also compared in anesthetized Sprague–Dawley rats by in vivo extracellular recordings. There were no significant differences in mechanical and thermal pain thresholds following levobupivacaine or bupivacaine injection at 0.025%, 0.0625%, and 0.125%. There was also no significant difference in tactile detection threshold following levobupivacaine or bupivacaine injection at 0.125%. However, tactile detection threshold was significantly higher after administration of bupivacaine at 0.025% and 0.0625% compared to equivalent doses of levobupivacaine. Subcutaneous injection of bupivacaine at 0.05% also induced significantly greater inhibition of SDH neuron spiking activity evoked by innocuous stimuli compared to an equivalent dose of levobupivacaine, while there was no significant difference in suppression of spiking activity evoked by noxious stimuli. Low-dose bupivacaine induces greater suppression tactile sensation than low-dose levobupivacaine. Thus, low-dose levobupivacaine demonstrates relatively greater blocking selectivity for noxious over innocuous stimuli compared to low-dose bupivacaine. Levobupivacaine may be advantageous for applications where pain must be suppressed but non-nociceptive sensations maintained.
{"title":"Differences in sensory nerve block between levobupivacaine and bupivacaine at low concentrations in humans and animals","authors":"Akiyuki Sakamoto, Satoshi Tanaka, Takashi Ishida, Mikito Kawamata","doi":"10.1101/2024.06.23.24309364","DOIUrl":"https://doi.org/10.1101/2024.06.23.24309364","url":null,"abstract":"Physiochemical properties of levobupivacaine and bupivacaine are identical, but pharmacokinetic and pharmacodynamics properties differ due to stereoselective interactions at the molecular sites of action. An evaluation of nerve block characteristicsis essential for optimal clinical application. This study compared the sensory blocking characteristics of levobupivacaine to bupivacaine in humans and model animals. Levobupivacaine and bupivacaine were compared for sensory block efficacy using a randomized, double-blinded, crossover study design. Eighteen healthy volunteers were randomized to receive levobupivacaine or bupivacaine by subcutaneous injection into the forearm, followed by the other drug 1 week later with injection order counterbalanced across subjects. Tactile detection and mechanical pain thresholds were determined using von Frey hairs and thermal pain threshold using a thermal stimulator. Effects of levobupivacaine and bupivacaine, on the spiking activity of spinal dorsal horn (SDH) neurons evoked by innocuous or noxious stimuli were also compared in anesthetized Sprague–Dawley rats by in vivo extracellular recordings. There were no significant differences in mechanical and thermal pain thresholds following levobupivacaine or bupivacaine injection at 0.025%, 0.0625%, and 0.125%. There was also no significant difference in tactile detection threshold following levobupivacaine or bupivacaine injection at 0.125%. However, tactile detection threshold was significantly higher after administration of bupivacaine at 0.025% and 0.0625% compared to equivalent doses of levobupivacaine. Subcutaneous injection of bupivacaine at 0.05% also induced significantly greater inhibition of SDH neuron spiking activity evoked by innocuous stimuli compared to an equivalent dose of levobupivacaine, while there was no significant difference in suppression of spiking activity evoked by noxious stimuli. Low-dose bupivacaine induces greater suppression tactile sensation than low-dose levobupivacaine. Thus, low-dose levobupivacaine demonstrates relatively greater blocking selectivity for noxious over innocuous stimuli compared to low-dose bupivacaine. Levobupivacaine may be advantageous for applications where pain must be suppressed but non-nociceptive sensations maintained.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141510702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1101/2024.06.21.24309278
Yang Hu, Ming Cheng Du, Yi Chen, Xiang Long, Jing Jing Jiang, yuan gong
We investigated the potential of intravenous lidocaine to reduce pain on awakening in a dose-dependent manner and aimed to determine the median effective dose of lidocaine in 200 children aged 3–12 years (American Society of Anesthesiologists physical status I–II) who underwent elective tonsillectomy with or without adenoidectomy at Yichang Central People’s Hospital. The patients were randomized into four dose groups (A–D: 0.0, 1.0, 1.5, and 2.0 mg/kg, respectively), and they underwent the same anesthetic induction and maintenance protocols. The primary outcome was pain on awakening, while secondary outcomes included pain scores at 1, 4, 12, and 24 h after awakening; incidences of laryngospasm, bronchospasm, or perioperative stridor; and time to extubation. Intraoperative cardiac events were classified as safety events. Our findings indicated that intravenous lidocaine dose-dependently reduced pain on awakening, with the median effective dose being 1.75 mg/kg. Significant differences were observed between groups A and D (P ≤ 0.001). No incidents of laryngospasm, bronchospasm, or perioperative stridor were observed. Furthermore, there were significant between-group differences in time to extubation (P ≤ 0.05). In conclusion, our study demonstrated that lidocaine dose-dependently reduced pain on awakening in children undergoing tonsillectomy with or without adenoidectomy, with no severe adverse events.
{"title":"Effect of intravenous lidocaine dose on pain upon awakening in pediatric tonsillectomy: A randomized trial","authors":"Yang Hu, Ming Cheng Du, Yi Chen, Xiang Long, Jing Jing Jiang, yuan gong","doi":"10.1101/2024.06.21.24309278","DOIUrl":"https://doi.org/10.1101/2024.06.21.24309278","url":null,"abstract":"We investigated the potential of intravenous lidocaine to reduce pain on awakening in a dose-dependent manner and aimed to determine the median effective dose of lidocaine in 200 children aged 3–12 years (American Society of Anesthesiologists physical status I–II) who underwent elective tonsillectomy with or without adenoidectomy at Yichang Central People’s Hospital. The patients were randomized into four dose groups (A–D: 0.0, 1.0, 1.5, and 2.0 mg/kg, respectively), and they underwent the same anesthetic induction and maintenance protocols. The primary outcome was pain on awakening, while secondary outcomes included pain scores at 1, 4, 12, and 24 h after awakening; incidences of laryngospasm, bronchospasm, or perioperative stridor; and time to extubation. Intraoperative cardiac events were classified as safety events. Our findings indicated that intravenous lidocaine dose-dependently reduced pain on awakening, with the median effective dose being 1.75 mg/kg. Significant differences were observed between groups A and D (P ≤ 0.001). No incidents of laryngospasm, bronchospasm, or perioperative stridor were observed. Furthermore, there were significant between-group differences in time to extubation (P ≤ 0.05). In conclusion, our study demonstrated that lidocaine dose-dependently reduced pain on awakening in children undergoing tonsillectomy with or without adenoidectomy, with no severe adverse events.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141510703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-12DOI: 10.1101/2024.04.10.24305650
Xiangyi Lin, Shengjie Chen, Huiyan Liang
Background Hysteroscopy is considered the gold standard for the evaluation and treatment of uterine and endometrial lesions, but the operation is accompanied by severe pain, so it needs to be performed under anesthesia. Currently, a new sedative drug, remimazolam tosilate, can be used in digestive endoscopy and bronchoscopy. We will study its effect on hysteroscopy and its impact on patient recovery time and hospital discharge time.
{"title":"Recovery and discharge time between remimazolam tosylate and propofol in hysteroscopy anesthesia: a randomized controlled study","authors":"Xiangyi Lin, Shengjie Chen, Huiyan Liang","doi":"10.1101/2024.04.10.24305650","DOIUrl":"https://doi.org/10.1101/2024.04.10.24305650","url":null,"abstract":"<strong>Background</strong> Hysteroscopy is considered the gold standard for the evaluation and treatment of uterine and endometrial lesions, but the operation is accompanied by severe pain, so it needs to be performed under anesthesia. Currently, a new sedative drug, remimazolam tosilate, can be used in digestive endoscopy and bronchoscopy. We will study its effect on hysteroscopy and its impact on patient recovery time and hospital discharge time.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-12DOI: 10.1101/2024.04.11.24305499
D Girijanandan Menon, Manjit George, Salih V Salim, R. Sreekumar, Sam Philip, Roshin K Mathew, Princymol Bju, Merin Helen Mathai
Textbooks of anaesthesia describe in detail the calculations associated with splitting ratios created in variable bypass vapourisers. These calculations are based on assumptions of carrier gas flow (eg:assume 150 ml) as practised with measured flow vaporizers[1,2]. Carrier gas flow in a variable bypass vaporizer is agent specific,dynamic,unknown and operator independent.Therefore assuming carrier gas flow in calculations related to variable bypass vaporisers is without rationale[3]. In spite of technological advance,the amount of vapour produced is calculated based on clinically impractical assumptions. A simple method and formula is suggested for the quick estimate of vapour output, carrier gas flow and determine the splitting ratio while operating a sevoflurane variable bypass vaporizer.
{"title":"Splitting ratio in sevoflurane vapouriser-a relook on calculations","authors":"D Girijanandan Menon, Manjit George, Salih V Salim, R. Sreekumar, Sam Philip, Roshin K Mathew, Princymol Bju, Merin Helen Mathai","doi":"10.1101/2024.04.11.24305499","DOIUrl":"https://doi.org/10.1101/2024.04.11.24305499","url":null,"abstract":"Textbooks of anaesthesia describe in detail the calculations associated with splitting ratios created in <em>variable bypass vapourisers</em>. These calculations are based on assumptions of carrier gas flow (eg:assume 150 ml) as practised with <em>measured flow vaporizers</em>[1,2]. Carrier gas flow in a variable bypass vaporizer is agent specific,dynamic,unknown and operator independent.Therefore assuming carrier gas flow in calculations related to variable bypass vaporisers is without rationale[3]. In spite of technological advance,the amount of vapour produced is calculated based on clinically impractical assumptions. A simple method and formula is suggested for the quick estimate of vapour output, carrier gas flow and determine the splitting ratio while operating a sevoflurane variable bypass vaporizer.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-06DOI: 10.1101/2024.04.05.24305392
Tyler V Elliott, Joseph C Goldstein, Heidi V Goldstein
Purpose This study aims to investigate the current state and sentiment of artificial intelligence (AI) training in North American anesthesiology residency programs, assessing existing AI education landscapes, identifying barriers to implementation, and understanding program directors’ expectations for AI’s impact on the field.
{"title":"The Current State & Sentiment of Artificial Intelligence in North American Anesthesiology Residency Programs","authors":"Tyler V Elliott, Joseph C Goldstein, Heidi V Goldstein","doi":"10.1101/2024.04.05.24305392","DOIUrl":"https://doi.org/10.1101/2024.04.05.24305392","url":null,"abstract":"<strong>Purpose</strong> This study aims to investigate the current state and sentiment of artificial intelligence (AI) training in North American anesthesiology residency programs, assessing existing AI education landscapes, identifying barriers to implementation, and understanding program directors’ expectations for AI’s impact on the field.","PeriodicalId":501303,"journal":{"name":"medRxiv - Anesthesia","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：