Administration of Low-dose Hyperbaric Bupivacaine for Spinal Anesthesia in the Setting of Outpatient Arthroplasty.

INTRODUCTION: With the rise of ambulatory surgery centers (ASCs), rapid motor and sensory recovery after anesthesia is crucial. The purpose of this study was to evaluate the safety and efficacy of low-dose single-shot hyperbaric bupivacaine for spinal anesthesia (SA) for patients undergoing outpatient arthroplasty. METHODS: Data were reviewed from a single ASC from 2018 to 2020 for two arthroplasty-trained surgeons for all patients with primary arthroplasties that had administration of low-dose hyperbaric bupivacaine. Data collected from the ASC records were then further evaluated for total spinal block time, length of blockade, time to discharge criteria, visual analog scale (VAS) scores, and time to discharge. RESULTS: Two hundred twenty-seven patients undergoing 244 primary arthroplasties received SA with low-dose hyperbaric bupivacaine. The volume of 0.75% bupivacaine varied: 115 patients received 0.8 mL (6 mg), 111 patients received 1.0 mL (7.5 mg), and 17 patients received 1.2 mL (9 mg). Total SA time averaged 144 minutes with a mean of 30 minutes from post anesthesia care unit arrival to motor recovery. The mean time from post anesthesia care unit arrival to discharge criteria was 89 minutes. The average VAS at discharge was 1.44; the average VAS on POD1 was 3.0. No episodes of urinary retention and no reports of transient neurologic symptoms were noted in the study population. CONCLUSION: Low-dose, single-shot hyperbaric bupivacaine SA is an effective option in the ASC for arthroplasty, providing a fast return of motor function, facilitating rapid discharge, and is safe with a relatively low-risk profile.

Hyperbaric bupivacaine versus prilocaine for spinal anesthesia combined with total intravenous anesthesia during oncological colon surgery in a 23-hour stay enhanced recovery protocol: A non-randomized study.

After the success of the enhanced recovery after surgery protocol, perioperative care has been further optimized in accelerated enhanced recovery pathways (ERPs), where optimal pain management is crucial. Spinal anesthesia was introduced as adjunct to general anesthesia to reduce postoperative pain and facilitate mobility. This study aimed to determine which spinal anesthetic agent provides best pain relief in accelerated ERP for colon carcinoma. This single center study was a secondary analysis conducted among patients included in the aCcelerated 23-Hour erAS care for colon surgEry study who underwent elective laparoscopic colon surgery. The first 30 patients included received total intravenous anesthesia combined with spinal anesthesia with prilocaine, the 30 patients subsequently included received spinal anesthesia with hyperbaric bupivacaine. Primary endpoint of this study was the total amount of morphine milligram equivalents (MMEs) administered during hospital stay. Secondary outcomes were amounts of MMEs administered in the recovery room and surgical ward, pain score using the numeric rating scale, complication rates and length of hospital stay. Compared to prilocaine, the total amount of MMEs administered was significantly lower in the bupivacaine group (n = 60, 16.3 vs 6.3, P = .049). Also, the amount of MMEs administered and median pain scores were significantly lower after intrathecal bupivacaine in the recovery room (MMEs 11.0 vs 0.0, P = .012 and numeric rating scale 2.0 vs 1.5, P = .004). On the surgical ward, median MMEs administered, and pain scores were comparable. Postoperative outcomes were similar in both groups. Spinal anesthesia with hyperbaric bupivacaine was associated with less opioid use and better pain reduction immediately after surgery compared to prilocaine within an accelerated ERP for elective, oncological colon surgery.

Effect of lidocaine on intraoperative blood pressure variability in patients undergoing major vascular surgery.

BACKGROUND: Dynamic fluctuations of arterial blood pressure known as blood pressure variability (BPV) may have short and long-term undesirable consequences. During surgical procedures blood pressure is usually measured in equal intervals allowing to assess its intraoperative variability, which significance for peri and post-operative period is still under debate. Lidocaine has positive cardiovascular effects, which may go beyond its antiarrhythmic activity. The aim of the study was to verify whether the use of intravenous lidocaine may affect intraoperative BPV in patients undergoing major vascular procedures. METHODS: We performed a post-hoc analysis of the data collected during the previous randomized clinical trial by Gajniak et al. In the original study patients undergoing elective abdominal aorta and/or iliac arteries open surgery were randomized into two groups to receive intravenous infusion of 1% lidocaine or placebo at the same infusion rate based on ideal body weight, in concomitance with general anesthesia. We analyzed systolic (SBP), diastolic (DBP) and mean arterial blood (MAP) pressure recorded in 5-minute intervals (from the first measurement before induction of general anaesthesia until the last after emergence from anaesthesia). Blood pressure variability was then calculated for SBP and MAP, and expressed as: standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and coefficient of hemodynamic stability (C10%), and compared between both groups. RESULTS: All calculated indexes were comparable between groups. In the lidocaine and placebo groups systolic blood pressure SD, CV, AVR and C10% were 20.17 vs. 19.28, 16.40 vs. 15.64, 14.74 vs. 14.08 and 0.45 vs. 0.45 respectively. No differences were observed regarding type of surgery, operating and anaesthetic time, administration of vasoactive agents and intravenous fluids, including blood products. CONCLUSION: In high-risk vascular surgery performed under general anesthesia, lidocaine infusion had no effect on arterial blood pressure variability. TRIAL REGISTRATION: ClinicalTrials.gov; NCT04691726 post-hoc analysis; date of registration 31/12/2020.

A systematic review of procedural modalities in the treatment of notalgia paresthetica.

BACKGROUND: Notalgia paresthetica (NP) is a rare condition characterized by localized pain and pruritus of the upper back, associated with a distinct area of hyperpigmentation. Given the lack of standardized treatment and the uncertain efficacy of available options, applying procedural methods is of growing interest in treating NP. AIMS: We sought to comprehensively evaluate the role of procedural treatments for NP. METHODS: We systematically searched PubMed/Medline, Ovid Embase, and Web of Science until November 14th, 2023. We also performed a citation search to detect all relevant studies. Original clinical studies published in the English language were included. RESULTS: Out of 243 articles, sixteen studies have reported various procedural modalities, with or without pharmacological components, in treating NP. Pharmacological procedures, including injections of botulinum toxin, lidocaine, and corticosteroids, led to a level of improvement in case reports and case series. However, botulinum toxin did not show acceptable results in a clinical trial. Moreover, non-pharmacological procedures were as follows: physical therapy, exercise therapy, kinesiotherapy, acupuncture and dry needling, electrical muscle stimulation, surgical decompression, and phototherapy. These treatments result in significant symptom control in refractory cases. Physical therapy can be considered a first-line choice or an alternative in refractory cases. CONCLUSION: Procedural modalities are critical in the multidisciplinary approach to NP, especially for patients who are refractory to topical and oral treatments. Procedural modalities include a spectrum of options that can be applied based on the disease's symptoms and severity.

Ultrasound-Guided Sacral Erector Spinae Plane Block: A Feasible Option for Pain Management During Magnetic Resonance Imaging: A Case Report.

Inability to remain motionless owing to pain during magnetic resonance imaging (MRI) may increase the need for sedation and analgesia. Here, we present a case where ultrasound-guided sacral erector spinae plane block (ESPB) was used successfully for pain management during an MRI in a patient suffering from severe sacral pain. Sacral ESPB was performed with a total of 30 mL of 0.25% bupivacaine at the level of the intermediate sacral crest. The patient achieved sensory block in the L5-S4 dermatomes without motor block, resulting in complete pain relief. This case report highlights the feasibility of ultrasound-guided sacral ESPB as a potential pain management technique.

Regional Anesthesia for Hip Arthroscopy.

Pain after hip arthroscopy can be severe, yet we lack a consensus method for non-narcotic analgesia. Here we describe anatomic elements of hip arthroscopy and our current understanding of the relevant sensory innervation as a prelude to the evaluation of locoregional analgesic techniques. Many regional nerve blocks and local anesthetic infiltration techniques are reviewed, including 2 newer ultrasound fascial plane blocks. Further study of targeted, motor-sparing approaches, either ultrasound-guided or under direct surgical visualization is needed.

Continuous Catheter Techniques.

Continuous peripheral nerve block catheters are simple in concept: percutaneously inserting a catheter adjacent to a peripheral nerve. This procedure is followed by local anesthetic infusion via the catheter that can be titrated to effect for extended anesthesia or analgesia in the perioperative period. The reported benefits of peripheral nerve catheters used in the surgical population include improved pain scores, decreased narcotic use, decreased nausea/vomiting, decreased pruritus, decreased sedation, improved sleep, and improved patient satisfaction.

Regional Anesthesia Complications and Contraindications.

Regional anesthesia has a strong role in minimizing post-operative pain, decreasing narcotic use and PONV, and, therefore, speeding discharge times. However, as with any procedure, regional anesthesia has both benefits and risks. It is important to identify the complications and contraindications related to regional anesthesia, which patient populations are at highest risk, and how to mitigate those risks to the greatest extent possible. Overall, significant complications secondary to regional anesthesia remain low. While a variety of different regional anesthesia techniques exist, complications tend to fall within 4 broad categories: block failure, bleeding/hematoma, neurological injury, and local anesthetic toxicity.

Local Anesthetics, Local Anesthetic Systemic Toxicity (LAST), and Liposomal Bupivacaine.

Local anesthetics have played a vital role in the multimodal analgesia approach to patient care by decreasing the use of perioperative opioids, enhancing patient satisfaction, decreasing the incidence of postoperative nausea and vomiting, decreasing the length of hospital stay, and reducing the risk of chronic postsurgical pain. The opioid-reduced anesthetic management for perioperative analgesia has been largely successful with the use of local anesthetics during procedures such as peripheral nerve blocks and neuraxial analgesia. It is important that practitioners who use local anesthetics are aware of the risk factors, presentation, and management of local anesthetic systemic toxicity (LAST).

Local Anesthetic Systemic Toxicity (LAST): More Common Than You Think.

The number of anesthetic body procedures in the United States is rapidly increasing, with many being performed on an outpatient basis. These procedures are advertised as being safe, and many times the serious complications may not be discussed. Although local anesthetic systemic toxicity is a rare complication, it is associated with an increase in morbidity. The emergency department staff should be aware of the possibility of this rare complication, as well as the variety of resulting symptoms (from minor to severe), potential sequelae, and appropriate management for patients who have undergone an outpatient anesthetic body procedure. Multiple factors contribute to the development of local anesthetic systemic toxicity, resulting in life-threatening effects on the neurologic and cardiovascular systems. Also, the site of administration, along with the local anesthetic agent used, can impact the risk of the development of local anesthetic systemic toxicity. To minimize the risk and ensure the best possible outcome for these patients, emergency department staff must be highly aware of the mechanisms, risk factors, prevention, and management/treatment of local anesthetic systemic toxicity.

Erratum: Local Anesthetic Thoracoscopy for Undiagnosed Pleural Effusion.

An erratum was issued for: Local Anesthetic Thoracoscopy for Undiagnosed Pleural Effusion. The Authors section was updated from: Uffe Bodtger1,2 José M. Porcel3 Rahul Bhatnagar4,5 Mohammed Munavvar6,7 Casper Jensen1 Paul Frost Clementsen1,8 Daniel Bech Rasmussen1,2 1Respiratory Research Unit PLUZ, Department of Respiratory Medicine, Zealand University Hospital 2Institute of Regional Health Research, University of Southern Denmark 3Pleural Medicine Unit, Department of Internal Medicine, Hospital Universitari Arnau de Vilanova, IRBLleida 4Respiratory Department, Southmead Hospital, North Bristol NHS Trust 5Academic Respiratory Unit, University of Bristol 6Lancashire Teaching Hospitals 7University of Central Lancashire 8Centre for HR and Education, Copenhagen Academy for Medical Education and Simulation to: Uffe Bodtger1,2 José M. Porcel3 Rahul Bhatnagar4,5 Nick Maskell4,5 Mohammed Munavvar6,7 Casper Jensen1 Paul Frost Clementsen1,8 Daniel Bech Rasmussen1,2 1Respiratory Research Unit PLUZ, Department of Respiratory Medicine, Zealand University Hospital 2Institute of Regional Health Research, University of Southern Denmark 3Pleural Medicine Unit, Department of Internal Medicine, Hospital Universitari Arnau de Vilanova, IRBLleida 4Respiratory Department, Southmead Hospital, North Bristol NHS Trust 5Academic Respiratory Unit, University of Bristol 6Lancashire Teaching Hospitals 7University of Central Lancashire 8Centre for HR and Education, Copenhagen Academy for Medical Education and Simulation.

Perioperative analgesic effects of the erector spinae plane block with bupivacaine or bupivacaine-dexmedetomidine in dogs undergoing hemilaminectomy: A randomized controlled trial.

Objective: To compare the perioperative opioid requirements among dogs receiving an erector spinae plane (ESP) block with bupivacaine, with or without dexmedetomidine, and a control group. Animals and procedure: Thirty client-owned, healthy adult dogs undergoing hemilaminectomy were included in this randomized, prospective, blinded clinical study. Dogs were randomly assigned to 1 of 3 treatment groups: Group B, ESP block with bupivacaine; Group BD, ESP block with bupivacaine and dexmedetomidine; and Group C, control. Rescue intra- and postoperative analgesia consisted of fentanyl and methadone, respectively. Postoperative pain was evaluated using the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF). Results: In Group BD, 0/10 dogs required intraoperative fentanyl, compared to 9/10 in Group C (P < 0.001), whereas 1/10 required postoperative methadone, compared to 9/10 in Group B (P = 0.003) and 10/10 in Group C (P < 0.001). The total amount of intraoperative fentanyl (µg/kg) was 0 (0 to 4) in Group B and 0 (0 to 0) in BD, compared to 6 (0 to 8) in C (P = 0.004 and P < 0.001, respectively). Postoperative methadone (mg/kg) required during the first 12 h was 0.5 (0 to 1.4) in Group B (P = 0.003) and 0 (0 to 0) in BD (P < 0.001), compared to C (P = 0.003 and P < 0.001, respectively). Conclusion: An ESP block with bupivacaine, with or without dexmedetomidine, was associated with a reduction in perioperative opioid consumption and provided effective acute pain control.

Effets analgésiques périopératoires du bloc des érecteurs du rachis avec de la bupivacaïne ou de la bupivacaïne-dexmédétomidine chez les chiens subissant une hémilaminectomie: un essai contrôlé randomisé. Objectif: Comparer les besoins périopératoires en opioïdes chez les chiens recevant un bloc des érecteurs de la colonne vertébrale (ESP) avec de la bupivacaïne, avec ou sans dexmédétomidine, et un groupe témoin. Animaux et procédure: Trente chiens adultes en bonne santé appartenant à des clients subissant une hémilaminectomie ont été inclus dans cette étude clinique randomisée, prospective et en aveugle. Les chiens ont été répartis au hasard dans 1 des 3 groupes de traitement: groupe B, bloc ESP avec bupivacaïne; groupe BD, bloc ESP avec bupivacaïne et dexmédétomidine; et groupe C, témoin. L'analgésie de secours peropératoire et postopératoire consistait respectivement en fentanyl et en méthadone. La douleur postopératoire a été évaluée à l'aide du formulaire abrégé de l'échelle de mesure de la douleur de Glasgow (CMPS-SF). Résultats: Dans le groupe BD, 0/10 chiens ont eu besoin de fentanyl peropératoire, contre 9/10 dans le groupe C (P < 0,001), tandis que 1/10 ont eu besoin de méthadone postopératoire, contre 9/10 dans le groupe B (P = 0,003) et 10/10 dans le groupe C (P < 0,001). La quantité totale de fentanyl peropératoire (µg/kg) était de 0 (0 à 4) dans le groupe B et de 0 (0 à 0) dans le groupe BD, contre 6 (0 à 8) dans le groupe C (P = 0,004 et P < 0,001, respectivement). La méthadone postopératoire (mg/kg) nécessaire au cours des 12 premières heures était de 0,5 (0 à 1,4) dans le groupe B (P = 0,003) et de 0 (0 à 0) dans le groupe BD (P < 0,001), par rapport au groupe C (P = 0,003). et P < 0,001, respectivement). Conclusion: Un bloc ESP avec de la bupivacaïne, avec ou sans dexmédétomidine, a été associé à une réduction de la consommation peropératoire d'opioïdes et a permis un contrôle efficace de la douleur aiguë.(Traduit par Dr Serge Messier).

Effect of pre-incisional and peritoneal local anesthetics administration on colon anastomosis and wound healing.

BACKGROUND: Previous research has shown that levobupivacaine is as effective as bupivacaine but carries a lower risk of cardiac and central nervous system toxicity. This study explores whether levobupivacaine and bupivacaine are preferable for all patients, includ-ing those with comorbidities, particularly focusing on their effects on colonic anastomosis. The primary objective is to examine the influence of levobupivacaine and bupivacaine on colonic anastomosis. Additionally, the study will assess their impact on wound healing and their anti-adhesive properties. METHODS: Conducted between July 28, 2022, to August 4, 2022, at the Hamidiye Animal Experiments Laboratory, this study was approved by the University Science Health, Hamidiye Animal Experiments Local Ethics Committee. This study was conducted using 21 male Sprague rats aged 16-20 weeks. The rats were allocated into three equal groups of seven each: Group C: pre-incisional isotonic; Group B: pre-incisional bupivacaine; and Group L: pre-incisional levobupivacaine. Macroscopic adhesion scores (MAS) were recorded during laparotomy and tissue samples were taken for histopathological examination and hydroxyproline levels measurement. Wound tensile strength along the middle incision line and anastomotic burst pressure were also assessed. RESULTS: MAS was statistically significantly lower in Groups B and L compared to Group C (p<0.001). The wound histopathology score (WHS) was significantly higher in Group L than in Group B (p=0.021). Colon histopathology scores (CHSs) were also signifi-cantly higher in Group L compared to Group C (p=0.011). CONCLUSION: TThe study found that bupivacaine and levobupivacaine did not significantly enhance wound healing, although le-vobupivacaine significantly improved WHS relative to bupivacaine. According to the findings of this study, levobupivacaine can enhance clinical practice by being used in patients undergoing colon anastomosis. It contributes significantly to the durability of colon anasto-mosis, has a more positive effect on wound healing compared to bupivacaine, and exhibits anti-adhesive properties. Additional clinical trials are necessary to validate these results further.

[Improving the effectiveness of local anesthesia in patients with arterial hypertension in the provision of emergency dental care]. / Povyshenie effektivnosti mestnogo obezbolivaniya u patsientov s arterial'noi gipertenziei pri okazanii neotlozhnoi stomatologicheskoi pomoshchi.

THE AIM OF THE STUDY: Was to evaluate the use of Ketorol Express as a preventive analgesia to increase the effectiveness of local anesthesia in providing emergency dental care to patients with arterial hypertension. MATERIALS AND METHODS: The study was conducted on the basis of the state autonomous healthcare institution of the Moscow region «Royal Dental Clinic¼ with the participation of 83 people. The patients were divided into two groups. In group 1, Ketorol Express was prescribed as a preventive analgesia in a dosage of 20 mg before local anesthesia. Patients of group 2 underwent dental interventions without the use of preventive analgesia. A 3% solution of mepivacaine was used as a local analgesic solution. For a subjective assessment of the effectiveness of anesthesia, use a visual analog scale. All patients had their blood pressure and heart rate measured before and after the interventions and hemodynamic parameters were continuously monitored during emergency dental care. RESULTS: In group 1, the effectiveness of combined anesthesia with the infiltration method of local anesthetic administration was 93±1.17%, according to the patient, 94±1.47%, according to the doctor, with the conductive method of anesthesia at the mandibular orifice - according to the patient it was 91±1.01%, according to the doctor 92± 1.36%. In group 2, when providing emergency dental care with the infiltration method of administration of 3% mepivacaine the anesthesia was effective in 80±1.97% of cases according to the patient and in 80±1.17% of cases according to the doctor, with the conductive method of anesthesia at the mandibular orifice, the effectiveness of anesthesia according to the patient was 82±1.11%, according to the doctor 85±1.23%. CONCLUSION: The results of the study demonstrated a statistically significant increase in the effectiveness of local anesthesia performed with a 3% solution of mepivacaine in patients with arterial hypertension due to the use of preventive analgesia with Ketorol Express at a dosage of 20 mg (2 tablets of 10 mg) in emergency dental care with registration and analysis of changes in hemodynamic parameters.

Effectiveness of Animal-Assisted Activity on Pain Perception and Anxiety of Children Undergoing Intraoral Local Anesthetic Administration.

Purpose: To investigate the impact of animal-assisted activity (AAA) involving a dog (play therapy) on reducing the pain experienced by children during the administration of local anesthetic (LA). Methods: Children between the ages of eight and 12 years who required LA administration were randomized into an AAA group and a control group. Baseline data for the simplified Modified Child Dental Anxiety Scale-Faces version (MCDAS[f]) was recorded, followed by the implementation of either AAA with standard care or standard care alone. The conventional protocol was followed for the administration of LA. Procedural pain was evaluated using both the Faces Pain Scale-Revised (FPS-R) and the Faces, Legs, Activity, Cry, and Consolability Scale (FLACC). All variations in pulse were also recorded. After the procedure, a simplified MCDAS(f) was recorded once again. The data were tabulated and statistically analyzed. Results: The children in the AAA group reported lower pain scores, as measured by FPS-R, compared to the control group (P =0.009). Pain, as observed in the FLACC scores, was also low in the experimental group (P <0.001). A notable reduction in anxiety scores (P <0.001) was observed among children assigned to the AAA group. Conclusion: AAA involving a dog led to a reduction in the pain experienced by children undergoing LA administration, subsequently decreasing anxiety.

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

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

The Median Effective Dose of Intrathecal Hyperbaric Bupivacaine for Cesarean Section at Moderately High-Altitude.

Objective: Alterations in altitude can lead to an augmented requirement for local anesthesia among patients. Nevertheless, the necessity for an elevated dosage of local anesthetic for parturients at moderately high altitudes during spinal anesthesia for cesarean section remains uninvestigated. This up-down sequential study endeavors to determine the ED50 dose of bupivacaine required for spinal anesthesia during cesarean sections at moderately high-altitude. Methods: Thirty singleton parturients at moderately high altitude underwent elective cesarean section under combined spinal-epidural anesthesia. The up-and-down sequential method was employed, starting with an initial dose of 12mg (1.6mL) of 0.75% hyperbaric bupivacaine for the first participant. The dose for the next case was adjusted up or down by 0.75mg based on the effectiveness of the previous participant. Effectiveness was defined as the bilateral sensory block reaching T6 within 15 minutes after spinal anesthesia injection, without the need for additional epidural anesthesia before fetal delivery. The ED50 dose and 95% confidence interval were calculated using the Dixon sequential method and isotonic regression, respectively. The incidence of maternal hypotension, nausea, and vomiting during the study period was also recorded. Results: The ED50 of hyperbaric bupivacaine for spinal anesthesia in cesarean section was calculated as 8.23 mg (95% CI, 6.52-9.32 mg) using the Dixon up-and-down method. Further validation using isotonic regression yielded a value of 8.39 mg (95% CI, 7.48-9.30 mg), confirming the accuracy and sensitivity of the conclusion. During the operation, only 6 parturients experienced hypotension, and no adverse reactions such as nausea, vomiting, and shivering were observed. Conclusion: The ED50 dose of 0.75% hyperbaric bupivacaine for spinal anesthesia during cesarean section at moderately high altitude is 8.23 mg, which exceeds the ED50 dose typically required by parturients at low altitude. Comprehensive investigations are warranted to ascertain the ED90 or ED95 dose of local anesthetics for cesarean section at moderately high altitudes, thereby offering enhanced guidance for clinical practice.