Machine learning approach for predicting post-intubation hemodynamic instability (PIHI) index values: towards enhanced perioperative anesthesia quality and safety.

BACKGROUND: Adequate preoperative evaluation of the post-intubation hemodynamic instability (PIHI) is crucial for accurate risk assessment and efficient anesthesia management. However, the incorporation of this evaluation within a predictive framework have been insufficiently addressed and executed. This study aims to developed a machine learning approach for preoperatively and precisely predicting the PIHI index values. METHODS: In this retrospective study, the valid features were collected from 23,305 adult surgical patients at Peking Union Medical College Hospital between 2012 and 2020. Three hemodynamic response sequences including systolic pressure, diastolic pressure and heart rate, were utilized to design the post-intubation hemodynamic instability (PIHI) index by computing the integrated coefficient of variation (ICV) values. Different types of machine learning models were constructed to predict the ICV values, leveraging preoperative patient information and initiatory drug infusion. The models were trained and cross-validated based on balanced data using the SMOTETomek technique, and their performance was evaluated according to the mean absolute error (MAE), root mean square error (RMSE), mean absolute percentage error (MAPE) and R-squared index (R2). RESULTS: The ICV values were proved to be consistent with the anesthetists' ratings with Spearman correlation coefficient of 0.877 (P < 0.001), affirming its capability to effectively capture the PIHI variations. The extra tree regression model outperformed the other models in predicting the ICV values with the smallest MAE (0.0512, 95% CI: 0.0511-0.0513), RMSE (0.0792, 95% CI: 0.0790-0.0794), and MAPE (0.2086, 95% CI: 0.2077-0.2095) and the largest R2 (0.9047, 95% CI: 0.9043-0.9052). It was found that the features of age and preoperative hemodynamic status were the most important features for accurately predicting the ICV values. CONCLUSIONS: Our results demonstrate the potential of the machine learning approach in predicting PIHI index values, thereby preoperatively informing anesthetists the possible anesthetic risk and enabling the implementation of individualized and precise anesthesia interventions.

Tiletamine-Zolazepam, Ketamine, and Xylazine Anesthetic Protocol for High-Quality, High-Volume Spay and Neuter of Free-Roaming Cats in Seoul, Korea.

This study was performed to evaluate the anesthetic protocol used in the high-quality, high-volume spay and neuter (HQHVSN) of free-roaming cats in Seoul, Korea from 2017 to 2022. The evaluation was performed on a total of 1261 free-roaming cats, with an average weight of 3.48 ± 1.04 kg. The anesthetic combination tiletamine-zolazepam, ketamine, and xylazine (ZKX) was injected intramuscularly. The actual drug doses administered were tiletamine-zolazepam 5.52 ± 1.70 mg/kg, ketamine 8.94 ± 3.60 mg/kg, and xylazine 1.11 ± 0.34 mg/kg. Additional doses were required in 275 cats out of a total of 1261 (21.8%). Following anesthesia and surgery, 1257 cats (99.7%) were returned to their original locations. Four cats (0.3%) died postoperatively. The mean duration of anesthesia (from ZKX combination to yohimbine administration) was 26 ± 22 min for males and 55 ± 36 min for females, while the time from yohimbine administration to the recovery was 31 ± 22 min for males and 20 ± 17 min for females. The use of ZKX for HQHVSN of free-roaming cats is inexpensive, provides predictable results, can be administered quickly and easily in a small volume, and is associated with a low mortality rate during the first 72 h post-surgery.

Association between telomere length in the DNA of peripheral blood leukocytes and the propofol dose in anesthesia induction: an observational study

Abstract Introduction: Propofol is a widely used anesthetic and its dose is closely related to aging. Telomere length (TL) is a unique heritable trait, and emerging as a biomarker of aging, health and disease. Telomerase RNA component (TERC) plays an important role in maintaining TL. We proposed a hypothesis that propofol dose in general anesthesia can be predicted by measuring TL before operation, which greatly reduced the risk of anesthesia, especially the elderly. Methods: The association between the propofol dose in anesthesia induction and: TL in the DNA of peripheral blood leukocytes; body weight; sex; difference of the Bispectral Index (BIS) before and after anesthesia induction in patients was evaluated by multivariable linear regression analyses. The mutation at the 5'end or 3'end of TERC was detected. We recruited 100 patients of elective surgery. Results: We found that propofol dose in anesthesia induction was clearly correlated significantly with TL (r = 0.78, p < 0.001), body weight (r = 0.84, p = 0.004), sex (r = 0.83, p= 0.84, p = 0.004), sex (r = 0.83, p = 0.004), and difference of BIS before and after anesthesia induction (r = 0.85, p = 0.029). By comparing the absolute values of standardized regression coefficients (0.58, 0.21, 0.19, and 0.12) of the four variables, it can be seen that TL contributes the most to the propofol dose in anesthesia induction. However, the mutation at the 5' end or 3' end of TERC was not found. Conclusions: These findings provide preliminary evidence that the propofol dose in anesthesia induction was clearly correlated with genetically determined TL. TL may be a promising predictor of the propofol dose, which is beneficial to improve the safety of anesthesia and reduce perioperative complications.

Evaluation of a three-axial acceleromyography monitor in dogs compared with mechanomyography.

OBJECTIVE: To compare the ratio of the train-of-four (TOF) and double burst stimulation (DBS) obtained with three-axial acceleromyography (AMG) and mechanomyography (MMG) in dogs during recovery from a rocuronium-induced neuromuscular block. STUDY DESIGN: Prospective, randomized, experimental study. ANIMALS: A total of six intact healthy adult male Beagle dogs, weighing 9.1 ± 1.9 kg and aged 3-5 years. METHODS: Dogs were anesthetized with intravenous (IV) dexmedetomidine and propofol, and isoflurane in oxygen. Neuromuscular function was measured with AMG and MMG in the contralateral thoracic limbs. Rocuronium (0.5 mg kg-1) was administered IV, and the TOF and DBS ratios measured. During neuromuscular block offset, MMG values were recorded when AMG first reached ratios of 0.9 and 1.0. True recovery from neuromuscular block was determined as MMG ratio ≥ 0.9. The false-positive (AMG ≥ 0.9 or 1.0, and MMG ratio < 0.9) rate was determined. Paired values were compared, and bias and limits of agreement were calculated. Receiver operating characteristic (ROC) curves were created. RESULTS: When AMG first reached 0.9 and 1.0 during recovery, MMG values were lower (p < 0.040). When AMG reached 0.9, the false-positive rate was 29% with TOF and 27% with DBS. It decreased to 12% (TOF) and 11% (DBS) when a ratio of 1.0 was used. AMG values were higher than paired MMG values (p < 0.001). The AMG overestimated MMG by 24% and 22% for TOF and DBS, respectively. Areas under the ROC curves (95% confidence interval) were 0.91 (0.89, 0.94) and 0.86 (0.81, 0.94) for TOF and DBS, respectively. CONCLUSIONS: and clinical relevance The three-axial AMG monitor overestimated neuromuscular function and, in some cases, indicated adequate recovery despite the MMG ratio being < 0.9. A TOF or DBS ratio of at least 1.0 should be considered when monitoring recovery of neuromuscular block with this AMG device.

Association between telomere length in the DNA of peripheral blood leukocytes and the propofol dose in anesthesia induction: an observational study.

INTRODUCTION: Propofol is a widely used anesthetic and its dose is closely related to aging. Telomere length (TL) is a unique heritable trait, and emerging as a biomarker of aging, health and disease. Telomerase RNA component (TERC) plays an important role in maintaining TL. We proposed a hypothesis that propofol dose in general anesthesia can be predicted by measuring TL before operation, which greatly reduced the risk of anesthesia, especially the elderly. METHODS: The association between the propofol dose in anesthesia induction and: TL in the DNA of peripheral blood leukocytes; body weight; sex; difference of the Bispectral Index (BIS) before and after anesthesia induction in patients was evaluated by multivariable linear regression analyses. The mutation at the 5'end or 3'end of TERC was detected. We recruited 100 patients of elective surgery. RESULTS: We found that propofol dose in anesthesia induction was clearly correlated significantly with TL (r = 0.78, p < 0.001), body weight (r = 0.84, p = 0.004), sex (r = 0.83, p= 0.84, p = 0.004), sex (r = 0.83, p = 0.004), and difference of BIS before and after anesthesia induction (r = 0.85, p = 0.029). By comparing the absolute values of standardized regression coefficients (0.58, 0.21, 0.19, and 0.12) of the four variables, it can be seen that TL contributes the most to the propofol dose in anesthesia induction. However, the mutation at the 5' end or 3' end of TERC was not found. CONCLUSIONS: These findings provide preliminary evidence that the propofol dose in anesthesia induction was clearly correlated with genetically determined TL. TL may be a promising predictor of the propofol dose, which is beneficial to improve the safety of anesthesia and reduce perioperative complications.

Anesthetic Management for Pulmonary Resection: Current Concepts and Improving Safety of Anesthesia.

Increasingly complex procedures are routinely performed using minimally invasive approaches, allowing cancers to be resected with short hospital stays, minimal postsurgical discomfort, and improved odds of cancer-free survival. Along with these changes, the focus of anesthetic management for lung resection surgery has expanded from the provision of ideal surgical conditions and safe intraoperative patient care to include preoperative patient training and optimization and postoperative pain management techniques that can impact pulmonary outcomes as well as patient lengths of stay.

Tribute to Dr. Takuo Aoyagi, inventor of pulse oximetry.

INTRODUCTION: Dr. Takuo Aoyagi invented pulse oximetry in 1974. Pulse oximeters are widely used worldwide, most recently making headlines during the COVID-19 pandemic. Dr. Aoyagi passed away on April 18, 2020, aware of the significance of his invention, but still actively searching for the theory that would take his invention to new heights. METHOD: Many people who knew Dr. Aoyagi, or knew of him and his invention, agreed to participate in this tribute to his work. The authors, from Japan and around the world, represent all aspects of the development of medical devices, including scientists and engineers, clinicians, academics, business people, and clinical practitioners. RESULTS: While the idea of pulse oximetry originated in Japan, device development lagged in Japan due to a lack of business, clinical, and academic interest. Awareness of the importance of anesthesia safety in the US, due to academic foresight and media attention, in combination with excellence in technological innovation, led to widespread use of pulse oximetry around the world. CONCLUSION: Dr. Aoyagi's final wish was to find a theory of pulse oximetry. We hope this tribute to him and his invention will inspire a new generation of scientists, clinicians, and related organizations to secure the foundation of the theory.

Update on the safety of anesthesia in young children presenting for adenotonsillectomy.

Tonsillectomy with and without adenoidectomy is a frequently performed surgical procedure in children. Although a common procedure, it is not without significant risk. It is critical for anesthesiologists to consider preoperative, intraoperative, and postoperative patient factors and events to optimize safety, especially in young children. In the majority of cases, the indication for adenotonsillectomy in young children is obstructive breathing. Preoperative evaluation for patient comorbidities, especially obstructive sleep apnea, risk factors for a difficult airway, and history of recent illness are crucial to prepare the patient for surgery and develop an anesthetic plan. Communication and collaboration with the otolaryngologist is key to prevent and treat intraoperative events such as airway fires or hemorrhage. Postoperative analgesia planning is critical for safe pain control especially for those patients with a history of obstructive sleep apnea and opioid sensitivity. In young children, it is important to also consider the impact of anesthetic medications on the developing brain. This is an area of continuing research but needs to be weighed when planning for surgical treatment and when discussing risks and benefits with patients' families.

Benefits and Barriers to Increasing Regional Anesthesia in Resource-Limited Settings.

Safe and accessible surgical and anesthetic care is critically limited for over half of the world's population, particularly in Sub-Saharan African and Southeast Asian countries. Increasing the use of regional anesthesia in these areas has potential benefits regarding access, safety, and cost-effectiveness. Perioperative anesthesia-related mortality is significantly higher in resource-limited countries and every effort should be made to encourage the use of anesthetic techniques in these countries that are safest under the present conditions. Studies from Sub-Saharan Africa, although limited in number, have shown a lower risk of death with regional compared to general anesthesia. Regional anesthesia has the further benefit of decreasing the risk of COVID-19 spread to healthcare providers by avoiding the aerosol-generating procedures that occur during general anesthesia. Neuraxial regional anesthesia is relatively easy to teach and perform and is considered the anesthetic of choice for surgeries below the umbilicus in resource-limited settings due to its safety, efficacy, and low cost. Although regional anesthesia has multiple potential advantages, education and training of anesthetic providers in low-and-middle-income countries (LMIC) are a significant barrier to growth. Anesthesia professionals, especially in Sub-Saharan Africa, are often poorly supported and undervalued, and recruitment and retention of adequate numbers of trained practitioners are a continuing problem. Greater use of regional anesthesia could be one way to safely increase anesthesia access and simultaneously create value and enthusiasm for the field. Deficits in anesthesia infrastructure, equipment, and drugs also limit anesthesia capacity in low-and middle-income countries. Ultrasound-guided regional anesthesia may be helpful in improving access to safe and reliable anesthesia in low-resource countries as it continues to become more user-friendly, durable, and affordable.

The challenge of safe anesthesia in developing countries: defining the problems in a medical center in Cambodia.

BACKGROUND: The International Standards for a Safe Practice of Anesthesia (ISSPA) were developed on behalf of the World Federation of Societies of Anaesthesiologists and the World Health Organization. It has been recommend as an assessment tool that allows anesthetic providers in developing countries to assess their compliance and needs. This study was performed to describe the anesthesia service in one main public hospital during an 8-month medical mission in Cambodia and evaluate its anesthetic safety issues according to the ISSPA. METHODS: We conduct a retrospective study involving 1953 patients at the Preah Ket Mealea hospital. Patient demographics, anesthetic techniques, and complications were reviewed according to the registers of the anesthetic services and questionnaires. The inadequacies in personnel, facilities, equipment, medications, and conduct of anesthesia drugs were recorded using a checklist based on the ISSPA. RESULTS: A total of 1792 patients received general and regional anesthesia in the operating room, while 161 patients receiving sedation for gastroscopy. The patients' mean age was 45.0 ± 16.6 years (range, 17-87 years). The three most common surgical procedures were abdominal (52.0%; confidence interval [CI], 49.3-54.7), orthopedic (27.6%; CI, 25.2-29.9), and urological surgery (14.7%; CI, 12.8-16.6). General anesthesia, spinal anesthesia, and brachial plexus block were performed in 54.3% (CI, 51.7-56.8), 28.2% (CI, 25.9-30.5), and 9.4% (CI, 7.9-10.9) of patients, respectively. One death occurred. Twenty-six items related to professional aspects, monitoring, and conduct of anesthesia did not meet the ISSPA-recommended standards. A lack of commonly used drugs and monitoring equipment was noted, posing major threats to the safety of anesthesia practice, especially in emergency situations. CONCLUSIONS: This study adds to the scarce literature on anesthesia practice in low- and middle-income countries such as Cambodia. Future medical assistance should help to strengthen these countries' inadequacies, allowing for the adoption of international standards for the safe practice of anesthesia.

Anesthesia machine checkout and room setup: a randomized, single-blind, comparison of two teaching modalities.

BACKGROUND: Novel methods for teaching are needed to enhance the efficiency of academic anesthesia departments as well as provide approaches to learning that are aligned with current trends and advances in technology. METHODS: A video was produced that taught the key elements of anesthesia machine checkout and room set up. Novice learners were randomly assigned to receive either the new video format or traditional lecture-based format for this topic during their regularly scheduled lecture series. Primary outcome was the difference in written examination score before and after teaching between the two groups. Secondary outcome was the satisfaction score of the trainees in the two groups. RESULTS: Forty-two students assigned to the video group and 36 students assigned to the lecture group completed the study. Students in each group similar interest in anesthesia, pre-test scores, post-test scores, and final exam scores. The median posttest to pretest difference was greater in the video groups (3.5 (3.0-5.0) vs 2.5 (2.0-3.0), for video and lecture groups respectively, p 0.002). Despite improved test scores, students reported higher satisfaction the traditional, lecture-based format (22.0 (18.0-24.0) vs 24.0 (20.0-28.0), for video and lecture groups respectively, p <0.004). CONCLUSIONS: Higher pre-test to post-test improvements were observed among students in the video-based teaching group, however students rated traditional, live lectures higher than newer video-based teaching.