Anesthesia

Introduction Major open abdominal surgeries often result in moderate to severe pain during the first 24-48 hours postoperatively. Epidural analgesia is effective in managing pain for open abdominal and thoracic surgeries during this immediate postoperative period and is considered the gold standard in accelerated rehabilitation protocols. The effectiveness of this pain relief method depends on the precise placement of the catheter in the epidural space. Since the procedure is performed blindly and relies on the anesthesiologist's skill, coupled with variations in anatomical structures, the failure rate of catheter placement ranges from 12% to 30%. Identifying catheter misplacement early in the postoperative period is challenging, as residual anesthetic effects may mask its ineffectiveness if the catheter is positioned outside the epidural space. This challenge can result in uncontrolled postoperative pain later on. Given the inherent difficulties in catheter placement and the limitations of relying on indirect anatomical assessment and sensory cues, even experienced clinicians may find epidural catheter insertion challenging. Sensory testing and patient-reported pain scores, while useful, do not consistently offer objective confirmation of correct catheter placement. Therefore, more practical and objective methods are needed. Ultrasound Techniques Color Doppler ultrasound, which visualizes fluid dynamics and flow direction, and M-mode ultrasound, which provides grayscale images of movement, could offer valuable insights. When fluid is injected into a confined space like the epidural space, it is expected to create turbulence, which would appear as a burst of color on the Doppler image. This turbulence arises because the fluid encounters resistance as it moves through the narrow epidural space. Although studies have demonstrated the reliability of color Doppler ultrasound for visualizing fluid flow through a needle in the caudal space in both adults and children, this does not directly translate to assessing catheter placement in the lumbar epidural space. For example, case series by Riveros-Pérez et al. and Elsharkawy et al. reported that only 37% and 68% of epidural catheter tips were visible in the posterior complex using color Doppler, respectively. Studies have shown mixed results regarding their effectiveness, and their application to detecting catheter placement in the lumbar epidural space has yet to be fully established. M-mode ultrasound, on the other hand, emits a single beam of ultrasound that traverses various structures, generating echoes that provide information on the mobility of different areas. This mode produces grayscale images where movement can be observed. Epidurography Epidurography, performed using radiographs, computed tomography, or fluoroscopy, remains the gold standard for verifying catheter placement when analgesia fails. This technique involves injecting an iodinated contrast agent through the catheter into the epidural space. The distribution of the contrast medium allows for visualization of the catheter's placement and verification of the correct vertebral level. Although epidurography provides definitive confirmation of catheter placement and helps mitigate patient dissatisfaction due to analgesic failure, it is less practical in the surgical setting due to the bulky equipment and the complexity of the procedure. Safety of Contrast Medium in Epidurography Epidurography, which utilizes fluoroscopy, has been employed for several decades by interventional pain specialists. The incidence of adverse effects related to the contrast medium is extremely low, approximately 0.007%, due to the minimal volume of contrast required for the procedure. Typically, epidurography involves the injection of 3 to 5 ml of iodinated contrast agent with a concentration of 240 mg/ml to verify accurate epidural placement. The rate of allergic reactions to iodinated contrast agents used in CT scans is estimated at around 0.6%, with severe reactions occurring in approximately 0.04% of cases. Most reactions are mild and can be managed or prevented with corticosteroids or small doses of adrenaline. Radiation Exposure in Epidurography Radiation exposure is a critical consideration in ensuring patient safety. The effective radiation dose from fluoroscopic epidurography is approximately 1 mSv for a procedure lasting about 60 seconds. This dose is comparable to 10 days of natural background radiation exposure. It is important to monitor both the duration of the procedure and the total radiation dose administered, which can be recorded by the imaging equipment. Despite its extensive use and low-risk profile in interventional pain management, epidurography is not ideal for intraoperative settings, underscoring the need for more practical, real-time methods to ensure effective epidural analgesia. Justification The literature has not yet established a systematic, objective method for evaluating the positioning of epidural catheters within the epidural space. Current research is exploring whether color Doppler and M-mode ultrasound could serve as reliable diagnostic tools for confirming correct catheter placement. Although alternative techniques like epidurography are available, they are less favored due to their requirement for bulky equipment and the exposure of patients to ionizing radiation. In contrast, ultrasound is a non-invasive and patient-safe option that is easy to learn and perform, offering high sensitivity and specificity. Problem Statement In major abdominal surgeries performed under general anesthesia, combining epidural techniques with general anesthesia complicates the early evaluation of the catheter's sensory and analgesic blockade. This difficulty arises because residual pharmacological and anesthetic effects can alter the effectiveness of the neuraxial blockade analysis postoperatively. Delayed assessment of epidural analgesia can lead to significant issues in patient recovery, particularly due to the context-sensitive half-life of anesthetics and opioids, which may result in unmanaged pain hours later. Hypothesis Research Question: What is the diagnostic accuracy of using ultrasound with Color Doppler Mode and M Mode for detecting the location of the epidural catheter in the epidural space compared to epidurography? Null Hypothesis (H0): The diagnostic accuracy of ultrasound using Color Doppler Mode and M Mode for detecting the location of the epidural catheter is less than 15% of the sensitivity of epidurography. Alternative Hypothesis (H1): The diagnostic accuracy of ultrasound using Color Doppler Mode and M Mode for detecting the location of the epidural catheter is at least 15% of the sensitivity of epidurography. Objectives Main Objective: Evaluate and compare the diagnostic accuracy of ultrasound using M-mode and color Doppler mode for locating the epidural catheter against epidurography. Specific Objectives: * Document and analyze demographic characteristics. * Compare sonoanatomical distances and catheter positioning as determined by ultrasound in 2D Mode, M-mode, and color Doppler mode with those identified by epidurography. * Determine and compare the diagnostic accuracy of ultrasound versus epidurography. * Assess clinical and sensory block correlation with sensory tests and ultrasound findings. * Measure analgesic efficacy using the verbal numerical scale (0-10) and the PAIN OUT international questionnaire (POD1). Methods This study, approved by the Research and Ethics Committee of the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, will be conducted at this tertiary hospital in Mexico City. This is a prospective, observational diagnostic test study aimed at evaluating and comparing the diagnostic accuracy of ultrasound (M-mode and color Doppler) versus epidurography for locating the epidural catheter. The study will involve the use of epidurography and ultrasound for each patient to assess diagnostic accuracy and is designed as a comparative study. Eligible patients will be provided with a detailed explanation of the study and will be required to sign written informed consent before participation. Universe: Patients undergoing abdominal surgery requiring an epidural block for postoperative analgesia. Observation Units: Each patient scheduled for abdominal surgery requiring an epidural block. Sampling Method: Recruitment based on the need for an epidural block for postoperative analgesia. Data Collection Ultrasound and Epidurography While the patient remains in the post-anesthesia care unit (PACU), an initial ultrasound assessment will be conducted by a trained anesthesiologist from the acute pain service. This scan will last between 15 and 30 minutes, and the observer will record the findings using a Google Form. Upon discharge from the PACU, an epidurography will be performed in the radiology department, where a radiologist and an interventional pain physician will be available to conduct and interpret the results of the epidurography. Following the epidurography, another ultrasound scan will be conducted by a second trained anesthesiologist from the acute pain service to evaluate interobserver variability. Sensitivity Assessment Within the first 6 hours post-procedure, the acute pain management team will evaluate the sensitivity of the dermatomes corresponding to the surgical wound on the abdominal wall at the bedside. Two methods will be employed for this sensitivity assessment: pinprick (using a blunt needle for point stimulation) and cold pressure (applying a cotton swab with alcohol). These assessments will be conducted symmetrically, beginning with the T5 dermatome and progressing in a caudal direction along the abdominal wall to define the region of reduced sensitivity. Assessment of Pain at Rest and Dynamic Pain To evaluate pain characteristics and patient satisfaction, the international PAIN OUT questionnaire will be administered 24 hours after the procedure. This questionnaire will help in assessing both pain at rest and dynamic pain levels experienced by the patient. Scanning Protocol: A scanning protocol, developed and refined since January 2023, will be followed for the study. This protocol outlines the methodology for performing the ultrasound scans in our Institute. Ultrasound with Color Doppler Mode and M-Mode: A Sonosite Nanomax ultrasound device equipped with a 2-5 MHz curved probe will be used. This device includes both Color Doppler mode and M-mode capabilities, enabling real-time visualization of the epidural catheter's position and assessment of flow distribution within the epidural space. Epidurography Equipment in the Radiology Area: Fluoroscopy equipment will be employed to perform epidurography. This involves injecting a contrast agent (Iopamidol, 3-5 milliliters) into the epidural space to obtain images that assess the catheter's positioning. Data Recording Equipment: Data will be systematically recorded using a Google Form. This system will collect and store all relevant information obtained during the study, including ultrasound data, epidurography results, and other pertinent details necessary for subsequent analysis.

20 years ago, for the first time in Spain, a record was made of all the activity carried out by a medical speciality, called ANESCAT 2003. After 20 years, the increase in healthcare activity has exceeded the expectations and predictions that were made at the time. Therefore, it is necessary to make a new assessment of the work situation in which our speciality finds itself in order to be able to evaluate whether the increase in resources allocated has been proportional and therefore to be able to have objective data with a view to making new demands and planning future needs.

This prospective observational study aims to compare the clinical performance of two target-controlled infusion (TCI) models, Eleveld and Schnider, for propofol sedation in mechanically ventilated intensive care unit (ICU) patients. The study evaluates sedation depth, hemodynamic stability, and recovery profiles using the Bispectral Index (BIS) and Riker Sedation-Agitation Scale. Secondary outcomes include awakening time, total propofol dose, and incidence of delirium after sedation withdrawal. The findings may help identify the most reliable pharmacokinetic model for safe and effective ICU sedation.

This study is a prospective, single-center, observational validation study designed to develop and evaluate a reproducible external anatomical landmark for localization of the distal cephalic vein at the forearm in pediatric patients. The study aims to support accurate preprocedural placement of topical local anesthetic (EMLA) and to facilitate subsequent peripheral venous access in children by using ultrasound as the reference standard. Background and Rationale Peripheral venous access in young children is frequently challenging due to limited visibility and palpability of superficial veins. The cephalic vein at the distal forearm is a commonly used site for ultrasound-guided cannulation; however, standardized external anatomical landmarks for preprocedural localization of this vein are lacking, particularly in pediatric patients. As a result, opportunities for timely application of topical anesthetics are often missed, especially in ambulatory and day-surgery settings where parents are required to apply EMLA patches at home prior to hospital admission. Ultrasound provides accurate visualization of superficial venous anatomy and allows objective validation of surface landmark accuracy. This study seeks to define a practical, reproducible landmark for the distal cephalic vein and to assess whether this landmark can be applied reliably by anesthesia professionals as well as by parents or caregivers using a standardized visual instruction guide. Study Design and Setting The study is conducted at a single Swiss university children's hospital and consists of two sequential, non-interventional study parts. All ultrasound examinations are performed intraoperatively after induction of general anesthesia for clinically indicated elective surgery. No venipuncture or deviation from standard clinical care is performed as part of the study. Each participant contributes data at a single time point only. No follow-up visits or longitudinal assessments are planned. Study Procedures Study Part 1 - Pilot Phase (Landmark Development): In an initial pilot phase, ultrasound examinations of the distal cephalic vein are performed in a cohort of pediatric patients under general anesthesia. The vein's course, depth, and diameter are assessed, and the vein's trajectory is marked on the skin with a washable marker. Photographic documentation of the forearm is obtained. Based on these sonographic measurements and images, a reproducible external anatomical landmark is developed for use in the validation phase. Study Part 2 - Validation Phase: The predefined anatomical landmark is evaluated in two independent validation steps: Step 1 (Anesthesia Staff Application): Anesthesia professionals apply the landmark by marking the presumed vein location on the forearm using a washable marker, guided by a standardized visual instruction. After induction of anesthesia, ultrasound is used to determine whether the cephalic vein is located beneath the marked area and to document anatomical parameters. Step 2 (Parent/Caregiver Application): Parents or caregivers apply an EMLA patch to the forearm using the same visual instruction guide prior to surgery. After induction of anesthesia, the patch is removed and ultrasound examination is performed to assess whether the cephalic vein is located beneath the area covered by the patch. In both validation steps, ultrasound measurements are performed by anesthesia personnel not involved in the initial marking to reduce observer bias. Ultrasound Assessment Ultrasound examinations are performed using high-frequency linear probes suitable for pediatric vascular imaging. The following parameters are documented at the marked site: * Presence of the cephalic vein within the marked or EMLA-covered area * Distance between the center of the vein and the center of the marked area * Vein depth from the skin surface * Vein diameter * Proximal course of the vein over a distance of up to 3 cm All measurements are obtained with the patient under general anesthesia to avoid movement-related variability. Data Collection and Management Study data are recorded using standardized paper Case Report Forms (CRFs) and subsequently transferred to a secured electronic database. Data are pseudonymized at the time of collection. Ultrasound images and photographic documentation are stored digitally to allow verification if required. Source data include CRFs, ultrasound images, and relevant routine clinical data (e.g., age, weight). No biological samples are collected, and no questionnaires or laboratory tests are performed. Quality Assurance and Monitoring Several measures are implemented to ensure data quality and consistency: * Standardized ultrasound procedures and documentation checklists * Training and briefing of all participating sonographers * Use of standardized visual instruction guides for landmark application * Partial double data entry and random data checks * Internal monitoring by the principal investigator * Secure storage and version control of all study documents * The study may be subject to audits or inspections by the responsible ethics committee, with direct access to source data if required. Sample Size Considerations This is an exploratory, non-confirmatory study. A formal power calculation was not performed. The planned sample size for the validation phase is based on achieving sufficient precision in estimating the proportion of correctly localized veins. Inclusion of approximately 30 participants per validation subgroup allows estimation of the primary accuracy measure with acceptable confidence interval width for an exploratory anatomical validation study. Statistical Analysis Principles Data analysis is primarily descriptive. Continuous variables are summarized using measures of central tendency and dispersion, while categorical variables are summarized using proportions and confidence intervals. Exploratory analyses assess relationships between anatomical parameters and demographic variables such as age, body weight, and body mass index. No interim analyses are planned. Handling of Missing Data Missing data may occur due to technical limitations or incomplete documentation. Analyses are performed using available data only, without imputation. If the number of evaluable cases falls below predefined targets, recruitment may be extended to ensure adequate data completeness. Ethical and Safety Considerations The study involves minimal risk. All procedures are non-invasive and performed under general anesthesia as part of routine clinical care. No additional pain, radiation exposure, or biological sampling is involved. Data protection measures include pseudonymization during data collection and anonymization after completion of the analysis. The study is conducted in accordance with applicable ethical and regulatory requirements.

The study rationale is that prior to conducting a multisite randomized trial, it is necessary to identify relevant outcomes, understand barriers to greater use of local anesthesia, test study procedures, and confirm our ability to adequately recruit and randomly assign participants. Additionally, the proposed study will provide the applicant with critical training in the design, conduct, and analysis of clinical trials. This will uniquely position the applicant to change surgical care for older adults. More specifically, the investigators plan to demonstrate the ability to successfully randomize Veterans aged 60 years and older to local versus general anesthesia for inguinal hernia surgery, and to validate processes and instruments to measure relevant outcomes. Although the original NIA-approved proposal involved only two arms, open hernia repair using local anesthesia and open repair using local anesthesia, the study team subsequently published a paper that showed using local anesthesia for open hernia repair may also be superior to laparoscopic or robotic hernia repair. Consequently, a third arm is added to our pilot study: laparoscopic or robotic hernia repair with general anesthesia (these surgical approaches cannot be done using local anesthesia). The rationale is that use of laparoscopic or robotic inguinal hernia surgery, while still less common than open repair, is becoming more common and no prior randomized trials have compared laparoscopic/robotic surgery versus open repair using local anesthesia. Local or general anesthesia are the primary methods of anesthesia for inguinal hernia surgery for most surgeons (though some perform the operation under spinal or regional anesthesia, this is rare). Both approaches are used in clinical practice with acceptable known risks and complications. General anesthesia is associated with risks of hypotension, venous thromboembolism, heart attack, stroke, pulmonary dysfunction, cognitive dysfunction, allergic reaction, urinary retention, and malignant hyperthermia. The main risks of local anesthesia include allergic reaction and hypotension (when the anesthetic is improperly injected into a blood vessel). The primary objective is to: 1. demonstrate ability to successfully recruit, randomize, and retain patients aged 60 years and older for a randomized trial of local versus general anesthesia for inguinal hernia surgery, and 2. establish the ability to measure relevant outcomes and test protocols and study instruments for measuring key outcomes. The secondary objective is to generate preliminary comparisons between the study arms, to inform effect size estimates for a larger multisite trial.

With the approval of Ethics Committee of the McGill University Health Centre, a total of 69 patients undergoing upper extremity surgery (elbow and below) will be recruited. Recruitment will be carried out by an investigator not involved in patient care one day before surgery All ICBs will be supervised by the coauthors and conducted preoperatively in an induction room. After skin disinfection and draping, the ICB will be performed with a previously described technique. In each group, a proven 90% effective volume of 35 mL of local anesthetic solution will be injected. As LA solution, it will be used a mixture of lidocaine 1.0%-bupivacaine 0.25% with epinephrine 5 µ/mL plus PN 2 mg dexamethasone. The injectate will be slowly injected through the block needle. Patients will be randomized to receive the study drug, PN dexmedetomidine 0.67 mcg/kg or PN dexmedetomidine 1 mcg/kg, or PN dexmedetomidine 1.33 mcg/kg mixed with the above-mentioned LA solution. A research assistant (licensed anesthesiologist) will prepare the local anesthetic solutions and will add the study drug following the randomization order. The operator, patient, and investigator assessing the block will be blinded to group allocation. The primary outcome will be the duration of the motor block (defined as the temporal interval between the end of LA injection through the block needle and the return of movement to the hand and fingers) for patients with successful ICBs. Patients will be provided with a data sheet and asked to record the time at which motor function returns. An investigator blinded to group allocation will collect this data sheet in person (inpatients) or by phone (outpatients) on postoperative day 1.

INTRODUCTION Many newborn infants have difficulty breathing after birth. Some of these babies have a tube inserted into their "windpipe" (trachea) - an endotracheal tube (ETT) - through which they are given breathing support (ventilation). When clinicians attempt to intubate (insert an ETT), they use an instrument called a laryngoscope to view the airway in order to identify the entrance to the trachea (larynx). Standard laryngoscopes have a "blade" (which, despite its name, is not sharp) with a light at the tip. Doctors insert the blade into the baby's mouth to view the larynx. Traditionally, clinicians used a standard laryngoscope to look directly into the baby's mouth to view the larynx (direct laryngoscopy, DL). When clinicians attempt to intubate newborns with DL, less than half of first attempts are successful. Also adverse effects - such as falls in the blood oxygen levels (fall in oxygen saturation (SpO2), or "desaturation"), slowing down of the heart rate (bradycardia), oral trauma - are relatively common. In recent years, video laryngoscopes (VL) have been developed. In addition to a light, VL have a video camera at the tip of the blade. This camera acquires a view of the larynx and displays it on a screen that the clinician views when attempting intubation (indirect laryngoscopy). In a randomised study performed at the National Maternity Hospital, Dublin, Ireland, more infants were successfully intubated at the first attempt when clinicians used VL compared to DL \[79/107 (74%) versus 48/107 (45%), P\<0.001\]. While this study was large enough to show that VL resulted infants being successfully intubated at the first attempt in one hospital, it couldn't give information about how it might work in a range of hospitals, and it wasn't large enough to see what effect VL had on adverse events. There is a large difference in cost between a standard laryngoscope (approx. €300) and a video laryngoscope (approx. €21,000). This is a matter of concern for all hospitals, particularly in settings where resources are more limited. The investigators aim to assess whether VL compared to DL results in more infants being intubated at the first attempt without physiological instability. STUDY DESIGN A recent single centre study reported that that more newborn infants were successfully intubated at the first attempt when VL was used to indirectly view the airway compared to DL. This study was not large enough to determine the effect of VL on adverse effects that are seen commonly (e.g. desaturation) or more rarely (e.g. bradycardia, receipt of chest compressions or adrenaline, oral trauma) during intubation attempts. For the current study, the investigators chose a stepped-wedge cluster randomised controlled design, where the participating centre, rather than the individual infant, will be the unit of randomisation. This design has been found appropriate to test the effects of an intervention that encompasses a behavioural aspect and to implement interventions while studying them at the same time. In this study, all centres will begin in the "control group"; where clinicians will routinely attempt intubation with DL, as is their usual practice. At specified intervals, centres will be randomly assigned to cross over to the "intervention group", where clinicians will routinely attempt intubation with VL. All participating centers will have included patients in both arms by the end of the study. SAMPLE SIZE ESTIMATION To determine the intra-cluster correlation (that means the correlation between two observations from the same centre), the investigators used the dataset of the MONITOR trial that included infants from 7 delivery rooms worldwide. In this trial, the intra-cluster correlation for intubation in the delivery room was reported as 0.1. This complete stepped-wedge cluster-randomized design includes 21 time periods (including the baseline) and 20 centres that will be including patients, with each randomised to a unique sequence. Each time period lasts a fortnight. Each time period, 1 centre will switch their treatment from DL to VL. With all centres including 2 patients each time period, 42 patients will be included per centre which will provide a total sample size of 840 patients. Assuming a control proportion of 0.4, this sample will achieve 90% power (0.9091) to detect a treatment proportion of 0.55, assuming a conservative ICC of 0.05. The power is not very sensitive to ICC values up to 0.1 (power of \>90% to detect difference 40% versus 56%). The test statistic used is the two-sided Wald Z-Test. TREATMENT OF SUBJECTS DIRECT LARYNGOSCOPY (DL, control period) At the start of the study, clinicians at participating centres will attempt intubation using a standard laryngoscope to perform DL as is their normal practice. VIDEO LARYNGOSCOPY (VL, intervention period) For each centre, a lot will be drawn which indicates the month in which endotracheal intubation will be routinely attempted with VL rather than DL. In the month before the switch, centres will be provided with a C-MAC VL by the manufacturers, Karl Storz-Endoskop (Tuttlingen, Germany). The system will be provided on loan for the duration of the study and will consist of an 8" high-definition monitor with connecting cable and reusable straight Miller type blades size 0 and size 1. The equipment will be demonstrated by representatives from Karl Storz, and clinicians who intubate babies at participating hospitals will be encouraged to practice with the equipment on mannequins. We will have an virtual meeting with each centre in the week before they are due to switch to review the protocol, data collection and to answer any queries that they may have. All other procedures in the delivery room and NICU will be performed according to international and local guidelines. All other aspects of the approach to intubation at the participating centre are at the discretion of the local clinicians and should remain the same for the duration of the study; e.g.: * The drugs used before intubation attempts (e.g. opiate, atropine, curare-like drug) * The route by which intubation is usually attempted (i.e. oral or nasal) * Whether they use a stylet is routinely used * Whether supplemental oxygen is given during attempts

The study is being conducted to evaluate the safety and efficacy of bupivacaine liposome injection for local infiltration analgesia in pediatric orthopedic surgery in the real world.

The purpose of this study is to understand changes in heart function (how the heart pumps blood) and blood flow in people who receive general anesthesia during surgery. The researchers are particularly interested in the heart function and blood flow changes in people who experience low blood pressure (hypotension) after receiving anesthesia.

To observe and study the clinical effect of Huperzine A Injection on reducing postoperative delirium in elderly patients undergoing non-cardiac surgery