Showing papers in "Anesthesiology in 2020"

Intubation and Ventilation amid the COVID-19 Outbreak: Wuhan's Experience.

Abstract: The COVID-19 outbreak has led to 80,409 diagnosed cases and 3,012 deaths in mainland China based on the data released on March 4, 2020. Approximately 3.2% of patients with COVID-19 required intubation and invasive ventilation at some point in the disease course. Providing best practices regarding intubation and ventilation for an overwhelming number of patients with COVID-19 amid an enhanced risk of cross-infection is a daunting undertaking. The authors presented the experience of caring for the critically ill patients with COVID-19 in Wuhan. It is extremely important to follow strict self-protection precautions. Timely, but not premature, intubation is crucial to counter a progressively enlarging oxygen debt despite high-flow oxygen therapy and bilevel positive airway pressure ventilation. Thorough preparation, satisfactory preoxygenation, modified rapid sequence induction, and rapid intubation using a video laryngoscope are widely used intubation strategies in Wuhan. Lung-protective ventilation, prone position ventilation, and adequate sedation and analgesia are essential components of ventilation management.

Perioperative Use of Gabapentinoids for the Management of Postoperative Acute Pain.

Abstract: Background Widely used for acute pain management, the clinical benefit from perioperative use of gabapentinoids is uncertain The aim of this systematic review was to assess the analgesic effect and adverse events with the perioperative use of gabapentinoids in adult patients Methods Randomized controlled trials studying the use of gabapentinoids in adult patients undergoing surgery were included The primary outcome was the intensity of postoperative acute pain Secondary outcomes included the intensity of postoperative subacute pain, incidence of postoperative chronic pain, cumulative opioid use, persistent opioid use, lengths of stay, and adverse events The clinical significance of the summary estimates was assessed based on established thresholds for minimally important differences Results In total, 281 trials (N = 24,682 participants) were included in this meta-analysis Compared with controls, gabapentinoids were associated with a lower postoperative pain intensity (100-point scale) at 6 h (mean difference, -10; 95% CI, -12 to -9), 12 h (mean difference, -9; 95% CI, -10 to -7), 24 h (mean difference, -7; 95% CI, -8 to -6), and 48 h (mean difference, -3; 95% CI, -5 to -1) This effect was not clinically significant ranging below the minimally important difference (10 points out of 100) for each time point These results were consistent regardless of the type of drug (gabapentin or pregabalin) No effect was observed on pain intensity at 72 h, subacute and chronic pain The use of gabapentinoids was associated with a lower risk of postoperative nausea and vomiting but with more dizziness and visual disturbance Conclusions No clinically significant analgesic effect for the perioperative use of gabapentinoids was observed There was also no effect on the prevention of postoperative chronic pain and a greater risk of adverse events These results do not support the routine use of pregabalin or gabapentin for the management of postoperative pain in adult patients

COVID-19 Infection: Implications for Perioperative and Critical Care Physicians.

Abstract: Healthcare systems worldwide are responding to Coronavirus Disease 2019 (COVID-19), an emerging infectious syndrome caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus. Patients with COVID-19 can progress from asymptomatic or mild illness to hypoxemic respiratory failure or multisystem organ failure, necessitating intubation and intensive care management. Healthcare providers, and particularly anesthesiologists, are at the frontline of this epidemic, and they need to be aware of the best available evidence to guide therapeutic management of patients with COVID-19 and to keep themselves safe while doing so. Here, the authors review COVID-19 pathogenesis, presentation, diagnosis, and potential therapeutics, with a focus on management of COVID-19-associated respiratory failure. The authors draw on literature from other viral epidemics, treatment of acute respiratory distress syndrome, and recent publications on COVID-19, as well as guidelines from major health organizations. This review provides a comprehensive summary of the evidence currently available to guide management of critically ill patients with COVID-19.

Sugammadex versus Neostigmine for Reversal of Neuromuscular Blockade and Postoperative Pulmonary Complications (STRONGER): A Multicenter Matched Cohort Analysis

Abstract: Background: 5% of adult patients undergoing noncardiac inpatient surgery experience a major pulmonary complication. We hypothesized that the choice of neuromuscular blockade reversal (neostigmine versus sugammadex) may be associated with a lower incidence of major pulmonary complications.

Artificial Intelligence in Anesthesiology: Current Techniques, Clinical Applications, and Limitations

Abstract: Artificial intelligence has been advancing in fields including anesthesiology. This scoping review of the intersection of artificial intelligence and anesthesia research identified and summarized six themes of applications of artificial intelligence in anesthesiology: (1) depth of anesthesia monitoring, (2) control of anesthesia, (3) event and risk prediction, (4) ultrasound guidance, (5) pain management, and (6) operating room logistics. Based on papers identified in the review, several topics within artificial intelligence were described and summarized: (1) machine learning (including supervised, unsupervised, and reinforcement learning), (2) techniques in artificial intelligence (e.g., classical machine learning, neural networks and deep learning, Bayesian methods), and (3) major applied fields in artificial intelligence.The implications of artificial intelligence for the practicing anesthesiologist are discussed as are its limitations and the role of clinicians in further developing artificial intelligence for use in clinical care. Artificial intelligence has the potential to impact the practice of anesthesiology in aspects ranging from perioperative support to critical care delivery to outpatient pain management.

Perioperative Management of Patients Infected with the Novel Coronavirus: Recommendation from the Joint Task Force of the Chinese Society of Anesthesiology and the Chinese Association of Anesthesiologists.

Abstract: The outbreak of the new Coronavirus disease, COVID-19, has been involved in 77,262 cases in China as well as in 27 other countries as of February 24, 2020. Because the virus is novel to human beings, and there is no vaccine yet available, every individual is susceptible and can become infected. Healthcare workers are at high risk, and unfortunately, more than 3,000 healthcare workers in China have been infected. Anesthesiologists are among healthcare workers who are at an even higher risk of becoming infected because of their close contact with infected patients and high potential of exposure to respiratory droplets or aerosol from their patients' airways. In order to provide healthcare workers with updated recommendations on the management of patients in the perioperative setting as well as for emergency airway management outside of the operating room, the two largest anesthesia societies, the Chinese Society of Anesthesiology (CSA) and the Chinese Association of Anesthesiologists (CAA) have formed a task force to produce the recommendations. The task force hopes to help healthcare workers, particularly anesthesiologists, optimize the care of their patients and protect patients, healthcare workers, and the public from becoming infected. The recommendations were created mainly based on the practice and experience of anesthesiologists who provide care to patients in China. Therefore, adoption of these recommendations outside of China must be done with caution, and the local environment, culture, uniqueness of the healthcare system, and patients' needs should be considered. The task force will continuously update the recommendations and incorporate new information in future versions.

Perioperative Acute Kidney Injury

Abstract: Perioperative organ injury is among the leading causes of morbidity and mortality of surgical patients. Among different types of perioperative organ injury, acute kidney injury occurs particularly frequently and has an exceptionally detrimental effect on surgical outcomes. Currently, acute kidney injury is most commonly diagnosed by assessing increases in serum creatinine concentration or decreased urine output. Recently, novel biomarkers have become a focus of translational research for improving timely detection and prognosis for acute kidney injury. However, specificity and timing of biomarker release continue to present challenges to their integration into existing diagnostic regimens. Despite many clinical trials using various pharmacologic or nonpharmacologic interventions, reliable means to prevent or reverse acute kidney injury are still lacking. Nevertheless, several recent randomized multicenter trials provide new insights into renal replacement strategies, composition of intravenous fluid replacement, goal-directed fluid therapy, or remote ischemic preconditioning in their impact on perioperative acute kidney injury. This review provides an update on the latest progress toward the understanding of disease mechanism, diagnosis, and managing perioperative acute kidney injury, as well as highlights areas of ongoing research efforts for preventing and treating acute kidney injury in surgical patients.

Preoperative Risk and the Association between Hypotension and Postoperative Acute Kidney Injury.

Abstract: Background Despite the significant healthcare impact of acute kidney injury, little is known regarding prevention. Single-center data have implicated hypotension in developing postoperative acute kidney injury. The generalizability of this finding and the interaction between hypotension and baseline patient disease burden remain unknown. The authors sought to determine whether the association between intraoperative hypotension and acute kidney injury varies by preoperative risk. Methods Major noncardiac surgical procedures performed on adult patients across eight hospitals between 2008 and 2015 were reviewed. Derivation and validation cohorts were used, and cases were stratified into preoperative risk quartiles based upon comorbidities and surgical procedure. After preoperative risk stratification, associations between intraoperative hypotension and acute kidney injury were analyzed. Hypotension was defined as the lowest mean arterial pressure range achieved for more than 10 min; ranges were defined as absolute (mmHg) or relative (percentage of decrease from baseline). Results Among 138,021 cases reviewed, 12,431 (9.0%) developed postoperative acute kidney injury. Major risk factors included anemia, estimated glomerular filtration rate, surgery type, American Society of Anesthesiologists Physical Status, and expected anesthesia duration. Using such factors and others for risk stratification, patients with low baseline risk demonstrated no associations between intraoperative hypotension and acute kidney injury. Patients with medium risk demonstrated associations between severe-range intraoperative hypotension (mean arterial pressure less than 50 mmHg) and acute kidney injury (adjusted odds ratio, 2.62; 95% CI, 1.65 to 4.16 in validation cohort). In patients with the highest risk, mild hypotension ranges (mean arterial pressure 55 to 59 mmHg) were associated with acute kidney injury (adjusted odds ratio, 1.34; 95% CI, 1.16 to 1.56). Compared with absolute hypotension, relative hypotension demonstrated weak associations with acute kidney injury not replicable in the validation cohort. Conclusions Adult patients undergoing noncardiac surgery demonstrate varying associations with distinct levels of hypotension when stratified by preoperative risk factors. Specific levels of absolute hypotension, but not relative hypotension, are an important independent risk factor for acute kidney injury.

Accuracy and Feasibility of Clinically Applied Frailty Instruments before Surgery.

Abstract: BACKGROUND A barrier to routine preoperative frailty assessment is the large number of frailty instruments described. Previous systematic reviews estimate the association of frailty with outcomes, but none have evaluated outcomes at the individual instrument level or specific to clinical assessment of frailty, which must combine accuracy with feasibility to support clinical practice. METHODS The authors conducted a preregistered systematic review (CRD42019107551) of studies prospectively applying a frailty instrument in a clinical setting before surgery. Medline, Excerpta Medica Database, Cochrane Library and the Comprehensive Index to Nursing and Allied Health Literature, and Cochrane databases were searched using a peer-reviewed strategy. All stages of the review were completed in duplicate. The primary outcome was mortality and secondary outcomes reflected routinely collected and patient-centered measures; feasibility measures were also collected. Effect estimates were pooled using random-effects models or narratively synthesized. Risk of bias was assessed. RESULTS Seventy studies were included; 45 contributed to meta-analyses. Frailty was defined using 35 different instruments; five were meta-analyzed, with the Fried Phenotype having the largest number of studies. Most strongly associated with: mortality and nonfavorable discharge was the Clinical Frailty Scale (odds ratio, 4.89; 95% CI, 1.83 to 13.05 and odds ratio, 6.31; 95% CI, 4.00 to 9.94, respectively); complications was associated with the Edmonton Frail Scale (odds ratio, 2.93; 95% CI, 1.52 to 5.65); and delirium was associated with the Frailty Phenotype (odds ratio, 3.79; 95% CI, 1.75 to 8.22). The Clinical Frailty Scale had the highest reported measures of feasibility. CONCLUSIONS Clinicians should consider accuracy and feasibility when choosing a frailty instrument. Strong evidence in both domains support the Clinical Frailty Scale, while the Fried Phenotype may require a trade-off of accuracy with lower feasibility. EDITOR’S PERSPECTIVE

Pharmacokinetics and Pharmacodynamics of Remimazolam (CNS 7056) after Continuous Infusion in Healthy Male Volunteers: Part I. Pharmacokinetics and Clinical Pharmacodynamics.

Abstract: Background Remimazolam (CNS 7056) is a new ultra-short-acting benzodiazepine for intravenous sedation and anesthesia. Its pharmacokinetics and pharmacodynamics have been reported for bolus administration. This study aimed to investigate the pharmacokinetics and pharmacodynamics of remimazolam after continuous infusion. Methods Twenty healthy male volunteers (20 to 38 yr, 64 to 99 kg) received remimazolam as continuous intravenous infusion of 5 mg/min for 5 min, 3 mg/min for the next 15 min, and 1 mg/min for further 15 min. Pharmacokinetics of remimazolam and its metabolite were determined from arterial plasma concentrations. Sedation was assessed using the Modified Observer's Assessment of Alertness and Sedation scale. Pharmacokinetic-pharmacodynamic modeling was performed by population analysis. Hemodynamics and the electrocardiogram were also investigated. Results Pharmacokinetics was best described by a three-compartment model for remimazolam and a two-compartment model with transit compartment for the metabolite. Remimazolam showed a high clearance (1.15 ± 0.12 l/min, mean ± SD), a small steady-state volume of distribution (35.4 ± 4.2 l) and a short terminal half-life (70 ± 10 min). The simulated context-sensitive halftime after an infusion of 4 h was 6.8 ± 2.4 min. Loss of consciousness was observed 5 ± 1 min after start, and full alertness was regained 19 ± 7 min after stop of infusion. Pharmacodynamics of Modified Observer's Assessment of Alertness and Sedation score was best described by a sigmoid probability model with effect site compartment. The half-maximum effect site concentration for a Modified Observer's Assessment of Alertness and Sedation score less than or equal to 1 was 695 ± 239 ng/ml. The equilibration half-time between central and effect compartment was 2.7 ± 0.6 min. Mean arterial blood pressure decreased by 24 ± 6%, and heart rate increased by 28 ± 15%. Spontaneous breathing was maintained throughout the study. There was no significant prolongation of the QT interval of the electrocardiogram observed. Conclusions Remimazolam was characterized by a pharmacokinetic-pharmacodynamic profile with fast onset, fast recovery, and moderate hemodynamic side effects.

Perioperative Neurocognitive Disorder: State of the Preclinical Science.

Abstract: The purpose of this article is to provide a succinct summary of the different experimental approaches that have been used in preclinical postoperative cognitive dysfunction research, and an overview of the knowledge that has accrued. This is not intended to be a comprehensive review, but rather is intended to highlight how the many different approaches have contributed to our understanding of postoperative cognitive dysfunction, and to identify knowledge gaps to be filled by further research. The authors have organized this report by the level of experimental and systems complexity, starting with molecular and cellular approaches, then moving to intact invertebrates and vertebrate animal models. In addition, the authors' goal is to improve the quality and consistency of postoperative cognitive dysfunction and perioperative neurocognitive disorder research by promoting optimal study design, enhanced transparency, and "best practices" in experimental design and reporting to increase the likelihood of corroborating results. Thus, the authors conclude with general guidelines for designing, conducting and reporting perioperative neurocognitive disorder rodent research.

Precautions for Intubating Patients with COVID-19.

Abstract: To the Editor: The major challenges in managing patients with the novel coronavirus disease (COVID-19) are bilateral pneumonia and acute respiratory distress syndrome. Many patients with COVID-19 will be in critical condition and will need intubation. Human-to-human transmission has been confirmed, and the virus has spread across the world. Based on current real-time reports, there are 78,962 confirmed COVID-19 cases, with 7,952 patients still in critical condition as of February 28, 2020. Many have been intubated and many remain to be intubated. The problem is that the viral load in the airway is probably very high and is very contagious. This poses significant risks for these who are performing intubation. Anesthesia providers play a vital role in providing in-hospital intubation. However, they generally do not deal with patients with such highly contagious disease. The safety of the patient and the individuals who are involved in the intubation requires special consideration and precautions. Multiple articles related to the precautions of intubation in the perioperative settings have recently been published. Some are empirical recommendations from institutions outside of the epicenter of COVID-19. Here we present our updated first-hand experiences focusing on the safety of the patients and providers performing intubation in an extreme situation from the epicenter of COVID-19, Wuhan, China. As shown in figure 1, three medical providers, who are volunteers from Shanghai and Qingdao, traveled to Wuhan to assist with patients there.

Vital Signs Monitoring with Wearable Sensors in High-risk Surgical Patients: A Clinical Validation Study.

Abstract: Background Vital signs are usually recorded once every 8 h in patients at the hospital ward. Early signs of deterioration may therefore be missed. Wireless sensors have been developed that may capture patient deterioration earlier. The objective of this study was to determine whether two wearable patch sensors (SensiumVitals [Sensium Healthcare Ltd., United Kingdom] and HealthPatch [VitalConnect, USA]), a bed-based system (EarlySense [EarlySense Ltd., Israel]), and a patient-worn monitor (Masimo Radius-7 [Masimo Corporation, USA]) can reliably measure heart rate (HR) and respiratory rate (RR) continuously in patients recovering from major surgery. Methods In an observational method comparison study, HR and RR of high-risk surgical patients admitted to a step-down unit were simultaneously recorded with the devices under test and compared with an intensive care unit-grade monitoring system (XPREZZON [Spacelabs Healthcare, USA]) until transition to the ward. Outcome measures were 95% limits of agreement and bias. Clarke Error Grid analysis was performed to assess the ability to assist with correct treatment decisions. In addition, data loss and duration of data gaps were analyzed. Results Twenty-five high-risk surgical patients were included. More than 700 h of data were available for analysis. For HR, bias and limits of agreement were 1.0 (-6.3, 8.4), 1.3 (-0.5, 3.3), -1.4 (-5.1, 2.3), and -0.4 (-4.0, 3.1) for SensiumVitals, HealthPatch, EarlySense, and Masimo, respectively. For RR, these values were -0.8 (-7.4, 5.6), 0.4 (-3.9, 4.7), and 0.2 (-4.7, 4.4) respectively. HealthPatch overestimated RR, with a bias of 4.4 (limits: -4.4 to 13.3) breaths/minute. Data loss from wireless transmission varied from 13% (83 of 633 h) to 34% (122 of 360 h) for RR and 6% (47 of 727 h) to 27% (182 of 664 h) for HR. Conclusions All sensors were highly accurate for HR. For RR, the EarlySense, SensiumVitals sensor, and Masimo Radius-7 were reasonably accurate for RR. The accuracy for RR of the HealthPatch sensor was outside acceptable limits. Trend monitoring with wearable sensors could be valuable to timely detect patient deterioration.

Associations of Intraoperative Radial Arterial Systolic, Diastolic, Mean, and Pulse Pressures with Myocardial and Acute Kidney Injury after Noncardiac Surgery: A Retrospective Cohort Analysis.

Abstract: Background:Arterial pressure is a complex signal that can be characterized by systolic, mean, and diastolic components, along with pulse pressure (difference between systolic and diastolic pressures). The authors separately evaluated the strength of associations among intraoperative pressure compone

Sepsis-induced Coagulopathy and Disseminated Intravascular Coagulation.

Abstract: Coagulopathy, a common complication with sepsis, contributes to vascular injury and organ dysfunction. Early detection using diagnostic criteria for sepsis-induced coagulopathy is important to consider for potential clinical management.

Preventing Infection of Patients and Healthcare Workers Should Be the New Normal in the Era of Novel Coronavirus Epidemics.

Abstract: As we write this editorial, the world is waiting anxiously to find out whether the current SARS-CoV-2 (etiologic agent of coronavirus disease 2019; COVID19) epidemic will be contained or burgeon into a pandemic. By the time you read this editorial, perhaps the answer will be known. We would like to emphasize at the outset that this editorial represents the opinions of the authors at the time it was written when there is much still unknown about COVID-19. Readers are urged to utilize multiple sources of information including those offered by various professional organizations and government agencies, and to carefully consider differing opinions. Previous outbreaks of novel coronavirus infection (i.e., SARS, MERS) spread less widely than COVID-19 but had a higher mortality rate. The current mortality rate of COVID-19 appears to be approximately 2 to 3%, while the mortality rate during the 2003 SARS epidemic was 10 to 15%. While not wishing to minimize the importance of the risks posed by COVID-19, it is important to remember that the world is constantly awash in infectious diseases, some of which present ongoing significant threats to public health. For example, during 2018 to 2019 in the United States, influenza killed approximately 34,000 people, and during 2017 to 2018, 61,000 people. Healthcare-associated infections in the United States are thought to affect approximately 1.7 million patients annually, resulting in approximately 99,000 deaths. Novel coronavirus outbreaks may be particularly hazardous to healthcare workers. An early report of 138 hospitalized patients with COVID-19 pneumonia from Wuhan, China, found that approximately 40% of cases were presumed hospital-related transmissions, including 40 healthcare workers and 17 patients originally hospitalized for other reasons. A more recent publication from the Chinese Center for Disease Control and Prevention (Beijing, China) reported that as of February 11, 2020, there were 1,716 healthcare workers diagnosed with COVID-19 out of 44,672 confirmed cases, although most of the infected healthcare workers were confined to the initial epicenter of the outbreak (Hubei Province, China). During the 2003 SARS outbreak in Ontario, Canada, 51% of cases were healthcare workers. Healthcare worker involvement with tracheal intubation conferred a 13-fold higher relative risk ratio for acquiring SARS infection when compared to healthcare workers not participating in tracheal intubation. Preventing transmission of infectious diseases to patients and protecting healthcare workers should be a top priority every day, especially but not exclusively during recurring viral epidemics. While anesthesia providers have not traditionally considered themselves to be on the front lines of infection prevention, we have learned in recent years that organisms acquired in the hospital setting can originate from the anesthesia workplace and from the hands of anesthesia providers. In 2018, a writing group of the Society for Healthcare Epidemiology of America (Arlington, Virginia) published an expert guidance with recommendations for preventing transmission of pathogens in the anesthesia workplace. The group recognized the difficulty of cleaning the anesthesia workplace, especially the anesthesia machine and the anesthesia cart, in the short time typically allowed for

Brief Preoperative Screening for Frailty and Cognitive Impairment Predicts Delirium after Spine Surgery.

Abstract: BACKGROUND Frailty and cognitive impairment are associated with postoperative delirium, but are rarely assessed preoperatively. The study was designed to test the hypothesis that preoperative screening for frailty or cognitive impairment identifies patients at risk for postoperative delirium (primary outcome). METHODS In this prospective cohort study, the authors administered frailty and cognitive screening instruments to 229 patients greater than or equal to 70 yr old presenting for elective spine surgery. Screening for frailty (five-item FRAIL scale [measuring fatigue, resistance, ambulation, illness, and weight loss]) and cognition (Mini-Cog, Animal Verbal Fluency) were performed at the time of the preoperative evaluation. Demographic data, perioperative variables, and postoperative outcomes were gathered. Delirium was the primary outcome detected by either the Confusion Assessment Method, assessed daily from postoperative day 1 to 3 or until discharge, if patient was discharged sooner, or comprehensive chart review. Secondary outcomes were all other-cause complications, discharge not to home, and hospital length of stay. RESULTS The cohort was 75 [73 to 79 yr] years of age, 124 of 219 (57%) were male. Many scored positive for prefrailty (117 of 218; 54%), frailty (53 of 218; 24%), and cognitive impairment (50 to 82 of 219; 23 to 37%). Fifty-five patients (25%) developed delirium postoperatively. On multivariable analysis, frailty (scores 3 to 5 [odds ratio, 6.6; 95% CI, 1.96 to 21.9; P = 0.002]) versus robust (score 0) on the FRAIL scale, lower animal fluency scores (odds ratio, 1.08; 95% CI, 1.01 to 1.51; P = 0.036) for each point decrease in the number of animals named, and more invasive surgical procedures (odds ratio, 2.69; 95% CI, 1.31 to 5.50; P = 0.007) versus less invasive procedures were associated with postoperative delirium. CONCLUSIONS Screening for frailty and cognitive impairment preoperatively using the FRAIL scale and the Animal Verbal Fluency test in older elective spine surgery patients identifies those at high risk for the development of postoperative delirium. EDITOR’S PERSPECTIVE

Tau Contributes to Sevoflurane-induced Neurocognitive Impairment in Neonatal Mice.

Abstract: BACKGROUND Sevoflurane anesthesia induces Tau phosphorylation and cognitive impairment in neonatal but not in adult mice. This study tested the hypothesis that differences in brain Tau amounts and in the activity of mitochondria-adenosine triphosphate (ATP)-Nuak1-Tau cascade between the neonatal and adult mice contribute to the age-dependent effects of sevoflurane on cognitive function. METHODS 6- and 60-day-old mice of both sexes received anesthesia with 3% sevoflurane for 2 h daily for 3 days. Biochemical methods were used to measure amounts of Tau, phosphorylated Tau, Nuak1, ATP concentrations, and mitochondrial metabolism in the cerebral cortex and hippocampus. The Morris water maze test was used to evaluate cognitive function in the neonatal and adult mice. RESULTS Under baseline conditions and compared with 60-day-old mice, 6-day-old mice had higher amounts of Tau (2.6 ± 0.4 [arbitrary units, mean ± SD] vs. 1.3 ± 0.2; P < 0.001), Tau oligomer (0.3 ± 0.1 vs. 0.1 ± 0.1; P = 0.008), and Nuak1 (0.9 ± 0.3 vs. 0.3 ± 0.1; P = 0.025) but lesser amounts of ATP (0.8 ± 0.1 vs. 1.5 ± 0.1; P < 0.001) and mitochondrial metabolism (74.8 ± 14.1 [pmol/min] vs. 169.6 ± 15.3; P < 0.001) in the cerebral cortex. Compared with baseline conditions, sevoflurane anesthesia induced Tau phosphorylation at its serine 202/threonine 205 residues (1.1 ± 0.4 vs. 0.2 ± 0.1; P < 0.001) in the 6-day-old mice but not in the 60-day-old mice (0.05 ± 0.04 vs. 0.03 ± 0.01; P = 0.186). The sevoflurane-induced Tau phosphorylation and cognitive impairment in the neonatal mice were both attenuated by the inhibition of Nuak1 and the treatment of vitamin K2. CONCLUSIONS Higher brain Tau concentrations and lower brain mitochondrial metabolism in neonatal compared with adult mice contribute to developmental stage-dependent cognitive dysfunction after sevoflurane anesthesia.

Multimodal Analgesic Regimen for Spine SurgeryA Randomized Placebo-controlled Trial

Abstract: Background Various multimodal analgesic approaches have been proposed for spine surgery. The authors evaluated the effect of using a combination of four nonopioid analgesics versus placebo on Quality of Recovery, postoperative opioid consumption, and pain scores. Methods Adults having multilevel spine surgery who were at high risk for postoperative pain were double-blind randomized to placebos or the combination of single preoperative oral doses of acetaminophen 1,000 mg and gabapentin 600 mg, an infusion of ketamine 5 µg/kg/min throughout surgery, and an infusion of lidocaine 1.5 mg/kg/h intraoperatively and during the initial hour of recovery. Postoperative analgesia included acetaminophen, gabapentin, and opioids. The primary outcome was the Quality of Recovery 15-questionnaire (0 to 150 points, with 15% considered to be a clinically important difference) assessed on the third postoperative day. Secondary outcomes were opioid use in morphine equivalents (with 20% considered to be a clinically important change) and verbal-response pain scores (0 to 10, with a 1-point change considered important) over the initial postoperative 48 h. Results The trial was stopped early for futility per a priori guidelines. The average duration ± SD of surgery was 5.4 ± 2.1 h. The mean ± SD Quality of Recovery score was 109 ± 25 in the pathway patients (n = 150) versus 109 ± 23 in the placebo group (n = 149); estimated difference in means was 0 (95% CI, -6 to 6, P = 0.920). Pain management within the initial 48 postoperative hours was not superior in analgesic pathway group: 48-h opioid consumption median (Q1, Q3) was 72 (48, 113) mg in the analgesic pathway group and 75 (50, 152) mg in the placebo group, with the difference in medians being -9 (97.5% CI, -23 to 5, P = 0.175) mg. Mean 48-h pain scores were 4.8 ± 1.8 in the analgesic pathway group versus 5.2 ± 1.9 in the placebo group, with the difference in means being -0.4 (97.5% CI; -0.8, 0.1, P = 0.094). Conclusions An analgesic pathway based on preoperative acetaminophen and gabapentin, combined with intraoperative infusions of lidocaine and ketamine, did not improve recovery in patients who had multilevel spine surgery.

Cannabis Use Disorder and Perioperative Outcomes in Major Elective Surgeries: A Retrospective Cohort Analysis.

Abstract: BACKGROUND Although cannabis is known to have cardiovascular and psychoactive effects, the implications of its use before surgery are currently unknown. The objective of the present study was to determine whether patients with an active cannabis use disorder have an elevated risk of postoperative complications. METHODS The authors conducted a retrospective population-based cohort study of patients undergoing elective surgery in the United States using the Nationwide Inpatient Sample from 2006 to 2015. A sample of 4,186,622 inpatients 18 to 65 yr of age presenting for 1 of 11 elective surgeries including total knee replacement, total hip replacement, coronary artery bypass graft, caesarian section, cholecystectomy, colectomy, hysterectomy, breast surgery, hernia repair, laminectomy, and other spine surgeries was selected. The principal exposure was an active cannabis use disorder, as defined by International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) diagnostic codes for cannabis dependence and cannabis abuse. The primary outcome was a composite endpoint of in-hospital postoperative myocardial infarction, stroke, sepsis, deep vein thrombosis, pulmonary embolus, acute kidney injury requiring dialysis, respiratory failure, and in-hospital mortality. Secondary outcomes included hospital length of stay, total hospital costs, and the individual components of the composite endpoint. RESULTS The propensity-score matched-pairs cohort consisted of 27,206 patients. There was no statistically significant difference between patients with (400 of 13,603; 2.9%) and without (415 of 13,603; 3.1%) a reported active cannabis use disorder with regard to the composite perioperative outcome (unadjusted odds ratio = 1.29; 95% CI, 1.17 to 1.42; P < 0.001; Adjusted odds ratio = 0.97; 95% CI, 0.84 to 1.11; P = 0.63). However, the adjusted odds of postoperative myocardial infarction was 1.88 (95% CI, 1.31 to 2.69; P < 0.001) times higher for patients with a reported active cannabis use disorder (89 of 13,603; 0.7%) compared with those without (46 of 13,603; 0.3%) an active cannabis use disorder (unadjusted odds ratio = 2.88; 95% CI, 2.34 to 3.55; P < 0.001). CONCLUSIONS An active cannabis use disorder is associated with an increased perioperative risk of myocardial infarction.

Response of Chinese Anesthesiologists to the COVID-19 Outbreak.

Abstract: The coronavirus disease 2019, named COVID-19 officially by the World Health Organization (Geneva, Switzerland) on February 12, 2020, has spread at unprecedented speed. After the first outbreak in Wuhan, China, Chinese anesthesiologists encountered increasing numbers of infected patients since December 2019. Because the main route of transmission is via respiratory droplets and close contact, anesthesia providers are at a high risk when responding to the devastating mass emergency. So far, actions have been taken including but not limited to nationwide actions and online education regarding special procedures of airway management, oxygen therapy, ventilation support, hemodynamic management, sedation, and analgesia. As the epidemic situation has lasted for months (thus far), special platforms have also been set up to provide free mental health care to all anesthesia providers participating in acute and critical caring for COVID-19 patients. The current article documents the actions taken, lesson learned, and future work needed.

Anesthetic Management Using Multiple Closed-loop Systems and Delayed Neurocognitive Recovery: A Randomized Controlled Trial.

Abstract: Editor’s PerspectiveWhat We Already Know about This TopicRecommendations for anesthetic care are often difficult to implement in the intraoperative setting because of the requirement for continuous attentionWhat This Article Tells Us That Is NewClosed-loop, automated management of anesthetic, analge

Hypotension Prediction Index for Prevention of Hypotension during Moderate- to High-risk Noncardiac Surgery

Abstract: BACKGROUND The Hypotension Prediction Index is a commercially available algorithm, based on arterial waveform features, that predicts hypotension defined as mean arterial pressure less than 65 mmHg for at least 1 min. We therefore tested the primary hypothesis that index guidance reduces the duration and severity of hypotension during noncardiac surgery. METHODS We enrolled adults having moderate- or high-risk noncardiac surgery with invasive arterial pressure monitoring. Participating patients were randomized to hemodynamic management with or without index guidance. Clinicians caring for patients assigned to guidance were alerted when the index exceeded 85 (range, 0 to 100) and a treatment algorithm based on advanced hemodynamic parameters suggested vasopressor administration, fluid administration, inotrope administration, or observation. Primary outcome was the amount of hypotension, defined as time-weighted average mean arterial pressure less than 65 mmHg. Secondary outcomes were time-weighted mean pressures less than 60 and 55 mmHg. RESULTS Among 214 enrolled patients, guidance was provided for 105 (49%) patients randomly assigned to the index guidance group. The median (first quartile, third quartile) time-weighted average mean arterial pressure less than 65 mmHg was 0.14 (0.03, 0.37) in guided patients versus 0.14 (0.03, 0.39) mmHg in unguided patients: median difference (95% CI) of 0 (-0.03 to 0.04), P = 0.757. Index guidance therefore did not reduce amount of hypotension less than 65 mmHg, nor did it reduce hypotension less than 60 or 55 mmHg. Post hoc, guidance was associated with less hypotension when analysis was restricted to episodes during which clinicians intervened. CONCLUSIONS In this pilot trial, index guidance did not reduce the amount of intraoperative hypotension. Half of the alerts were not followed by treatment, presumably due to short warning time, complex treatment algorithm, or clinicians ignoring the alert. In the future we plan to use a lower index alert threshold and a simpler treatment algorithm that emphasizes prompt treatment. EDITOR’S PERSPECTIVE

Volatile versus Total Intravenous Anesthesia for Cancer Prognosis in Patients Having Digestive Cancer Surgery.

Abstract: BACKGROUND Previous experimental and clinical studies have shown that anesthetic agents have varying effects on cancer prognosis; however, the results were inconsistent among these studies. The authors compared overall and recurrence-free survival in patients given volatile or intravenous anesthesia for digestive tract cancer surgery. METHODS The authors selected patients who had elective esophagectomy, gastrectomy, hepatectomy, cholecystectomy, pancreatectomy, colectomy, and rectal cancer surgery from July 2010 to March 2018 using the Japanese Diagnosis Procedure Combination database. Patients were divided into a volatile anesthesia group (desflurane, sevoflurane, or isoflurane with/without nitrous oxide) and a propofol-based total intravenous anesthesia group. The authors hypothesized that total intravenous anesthesia is associated with greater overall and recurrence-free survival than volatile anesthesia. Subgroup analyses were performed for each type of surgery. RESULTS The authors identified 196,303 eligible patients (166,966 patients in the volatile anesthesia group and 29,337 patients in the propofol-based total intravenous anesthesia group). The numbers (proportions) of death in the volatile anesthesia and total intravenous anesthesia groups were 17,319 (10.4%) and 3,339 (11.4%), respectively. There were no significant differences between the two groups in overall survival (hazard ratio, 1.02; 95% CI, 0.98 to 1.07; P = 0.28) or recurrence-free survival (hazard ratio, 0.99; 95% CI, 0.96 to 1.03; P = 0.59), whereas instrumental variable analyses showed a slight difference in recurrence-free survival (hazard ratio, 0.92; 95% CI, 0.87 to 0.98; P = 0.01). Subgroup analyses showed no significant difference in overall or recurrence-free survival between the groups in any type of surgery. CONCLUSIONS Overall and recurrence-free survival were similar between volatile and intravenous anesthesia in patients having digestive tract surgery. Selection of the anesthetic approach for these patients should be based on other factors. EDITOR’S PERSPECTIVE

Spectral and Entropic Features Are Altered by Age in the Electroencephalogram in Patients under Sevoflurane Anesthesia.

Abstract: BACKGROUND Preexisting factors such as age and cognitive performance can influence the electroencephalogram (EEG) during general anesthesia. Specifically, spectral EEG power is lower in elderly, compared to younger, subjects. Here, the authors investigate age-related changes in EEG architecture in patients undergoing general anesthesia through a detailed examination of spectral and entropic measures. METHODS The authors retrospectively studied 180 frontal EEG recordings from patients undergoing general anesthesia, induced with propofol/fentanyl and maintained by sevoflurane at the Waikato Hospital in Hamilton, New Zealand. The authors calculated power spectral density and normalized power spectral density, the entropic measures approximate and permutation entropy, as well as the beta ratio and spectral entropy as exemplary parameters used in current monitoring systems from segments of EEG obtained before the onset of surgery (i.e., with no noxious stimulation). RESULTS The oldest quartile of patients had significantly lower 1/f characteristics (P < 0.001; area under the receiver operating characteristics curve, 0.84 [0.76 0.92]), indicative of a more uniform distribution of spectral power. Analysis of the normalized power spectral density revealed no significant impact of age on relative alpha (P = 0.693; area under the receiver operating characteristics curve, 0.52 [0.41 0.63]) and a significant but weak effect on relative beta power (P = 0.041; area under the receiver operating characteristics curve, 0.62 [0.52 0.73]). Using entropic parameters, the authors found a significant age-related change toward a more irregular and unpredictable EEG (permutation entropy: P < 0.001, area under the receiver operating characteristics curve, 0.81 [0.71 0.90]; approximate entropy: P < 0.001; area under the receiver operating characteristics curve, 0.76 [0.66 0.85]). With approximate entropy, the authors could also detect an age-induced change in alpha-band activity (P = 0.002; area under the receiver operating characteristics curve, 0.69 [0.60 78]). CONCLUSIONS Like the sleep literature, spectral and entropic EEG features under general anesthesia change with age revealing a shift toward a faster, more irregular, oscillatory composition of the EEG in older patients. Age-related changes in neurophysiological activity may underlie these findings however the contribution of age-related changes in filtering properties or the signal to noise ratio must also be considered. Regardless, most current EEG technology used to guide anesthetic management focus on spectral features, and improvements to these devices might involve integration of entropic features of the raw EEG.

Usefulness of Parasternal Intercostal Muscle Ultrasound during Weaning from Mechanical Ventilation

Abstract: Background: The assessment of diaphragm function with diaphragm ultrasound seems to bring important clinical information to describe diaphragm work and weakness. When the diaphragm is weak, extradiaphragmatic muscles may play an important role, but whether ultrasound can also assess their activity and function is unknown. This study aimed to (1) evaluate the feasibility of measuring the thickening of the parasternal intercostal and investigate the responsiveness of this muscle to assisted ventilation; and (2) evaluate whether a combined evaluation of the parasternal and the diaphragm could predict failure of a spontaneous breathing trial. Methods: First, an exploratory evaluation of the parasternal in 23 healthy subjects. Second, the responsiveness of parasternal to several pressure support levels were studied in 16 patients. Last, parasternal activity was compared in presence or absence of diaphragm dysfunction (assessed by magnetic stimulation of the phrenic nerves and ultrasound) and in case of success/failure of a spontaneous breathing trial in 54 patients. Results: The parasternal was easily accessible in all patients. The interobserver reproducibility was good (intraclass correlation coefficient, 0.77 (95% CI, 0.53 to 0.89). There was a progressive decrease in parasternal muscle thickening fraction with increasing levels of pressure support (Spearman ρ = -0.61 [95% CI, -0.74 to -0.44]; P < 0.0001) and an inverse correlation between parasternal muscle thickening fraction and the pressure generating capacity of the diaphragm (Spearman ρ = -0.79 [95% CI, -0.87 to -0.66]; P < 0.0001). The parasternal muscle thickening fraction was higher in patients with diaphragm dysfunction: 17% (10 to 25) versus 5% (3 to 8), P < 0.0001. The pressure generating capacity of the diaphragm, the diaphragm thickening fraction and the parasternal thickening fraction similarly predicted failure or the spontaneous breathing trial. Conclusions: Ultrasound assessment of the parasternal intercostal muscle is feasible in the intensive care unit and provides novel information regarding the respiratory capacity load balance.

Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain.

Abstract: Two regional analgesic modalities currently cleared by the U.S. Food and Drug Administration hold promise to provide postoperative analgesia free of many of the limitations of both opioids and local anesthetic-based techniques. Cryoneurolysis uses exceptionally low temperature to reversibly ablate a peripheral nerve, resulting in temporary analgesia. Where applicable, it offers a unique option given its extended duration of action measured in weeks to months after a single application. Percutaneous peripheral nerve stimulation involves inserting an insulated lead through a needle to lie adjacent to a peripheral nerve. Analgesia is produced by introducing electrical current with an external pulse generator. It is a unique regional analgesic in that it does not induce sensory, motor, or proprioception deficits and is cleared for up to 60 days of use. However, both modalities have limited validation when applied to acute pain, and randomized, controlled trials are required to define both benefits and risks.

Lung Ultrasound in Emergency and Critically Ill Patients: Number of Supervised Exams to Reach Basic Competence.

Abstract: Background Lung ultrasound is increasingly used in critically ill patients as an alternative to bedside chest radiography, but the best training method remains uncertain. This study describes a training curriculum allowing trainees to acquire basic competence. Methods This multicenter, prospective, and educational study was conducted in 10 Intensive Care Units in Brazil, China, France and Uruguay. One hundred residents, respiratory therapists, and critical care physicians without expertise in transthoracic ultrasound (trainees) were trained by 18 experts. The main study objective was to determine the number of supervised exams required to get the basic competence, defined as the trainees' ability to adequately classify lung regions with normal aeration, interstitial-alveolar syndrome, and lung consolidation. An initial 2-h video lecture provided the rationale for image formation and described the ultrasound patterns commonly observed in critically ill and emergency patients. Each trainee performed 25 bedside ultrasound examinations supervised by an expert. The progression in competence was assessed every five supervised examinations. In a new patient, 12 pulmonary regions were independently classified by the trainee and the expert. Results Progression in competence was derived from the analysis of 7,330 lung regions in 2,562 critically ill and emergency patients. After 25 supervised examinations, 80% of lung regions were adequately classified by trainees. The ultrasound examination mean duration was 8 to 10 min in experts and decreased from 19 to 12 min in trainees (after 5 vs. 25 supervised examinations). The median training duration was 52 (42, 82) days. Conclusions A training curriculum including 25 transthoracic ultrasound examinations supervised by an expert provides the basic skills for diagnosing normal lung aeration, interstitial-alveolar syndrome, and consolidation in emergency and critically ill patients.

Perioperative GabapentinoidsDeflating the Bubble

Abstract: Accepted for publication April 30, 2020. Published online first on June 26, 2020. From the Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina (E.D.K.); the Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, Palo Alto, California (J.D.C.); the Department of Anesthesiology, Stanford University School of Medicine, Stanford, California (J.D.C.); and the Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, Michigan (S.K.).

Persistent Postoperative Opioid Use: A Systematic Literature Search of Definitions and Population-based Cohort Study.

Abstract: Background While persistent opioid use after surgery has been the subject of a large number of studies, it is unknown how much variability in the definition of persistent use impacts the reported incidence across studies. The objective was to evaluate the incidence of persistent use estimated with different definitions using a single cohort of postoperative patients, as well as the ability of each definition to identify patients with opioid-related adverse events. Methods The literature was reviewed to identify observational studies that evaluated persistent opioid use among opioid-naive patients requiring surgery, and any definitions of persistent opioid use were extracted. Next, the authors performed a population-based cohort study of opioid-naive adults undergoing 1 of 18 surgical procedures from 2013 to 2017 in Ontario, Canada. The primary outcome was the incidence of persistent opioid use, defined by each extracted definition of persistent opioid use. The authors also assessed the sensitivity and specificity of each definition to identify patients with an opioid-related adverse event in the year after surgery. Results Twenty-nine different definitions of persistent opioid use were identified from 39 studies. Applying the different definitions to a cohort of 162,830 opioid-naive surgical patients, the incidence of persistent opioid use in the year after surgery ranged from 0.01% (n = 10) to 14.7% (n = 23,442), with a median of 0.7% (n = 1,061). Opioid-related overdose or diagnosis associated with opioid use disorder in the year of follow-up occurred in 164 patients (1 per 1,000 operations). The sensitivity of each definition to identify patients with the composite measure of opioid use disorder or opioid-related toxicity ranged from 0.01 to 0.36, while specificity ranged from 0.86 to 1.00. Conclusions The incidence of persistent opioid use reported after surgery varies more than 100-fold depending on the definition used. Definitions varied markedly in their sensitivity for identifying adverse opioid-related event, with low sensitivity overall across measures.