The 50 most-cited articles in Anesthesiology, 2019

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…

A review of anatomy, potential mechanisms of action, and techniques and summary of clinical evidence for quadratus lumborum block.

Surveys provide evidence on practice, attitudes, and knowledge. However, conducting good survey research is harder than it looks. The authors aim to provide guidance to both researchers and readers in conducting and interpreting survey research. Like all research, surveys should have clear research question(s) using the smallest possible number of high-quality, essential, survey questions (items) that will interest the target population. Both researchers and readers should put themselves in the position of the respondents. The survey questions should provide reproducible results (reliable), measure what they are supposed to measure (valid), and take less than 10 min to answer. Good survey research reports provide results with valid and reliable answers to the research question with an adequate response rate (at least 40%) and adequate precision (margin of error ideally 5% or less). Possible biases among those who did not respond (nonresponders) must be carefully analyzed and discussed. Quantitative results can be combined with qualitative results in mixed-methods research to provide…

BACKGROUND: Postoperative delirium and postoperative cognitive dysfunction share risk factors and may co-occur, but their relationship is not well established. The primary goals of this study were to describe the prevalence of postoperative cognitive dysfunction and to investigate its association with in-hospital delirium. The authors hypothesized that delirium would be a significant risk factor for postoperative cognitive dysfunction during follow-up. METHODS: This study used data from an observational study of cognitive outcomes after major noncardiac surgery, the Successful Aging after Elective Surgery study. Postoperative delirium was evaluated each hospital day with confusion assessment method-based interviews supplemented by chart reviews. Postoperative cognitive dysfunction was determined using methods adapted from the International Study of Postoperative Cognitive Dysfunction. Associations between delirium and postoperative cognitive dysfunction were examined at 1, 2, and 6 months. RESULTS: One hundred thirty-four of 560 participants (24%) developed delirium during…

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…

These practice guidelines update the Practice Guidelines for Central Venous Access: A Report by the American Society of Anesthesiologists Task Force on Central Venous Access, adopted by the American Society of Anesthesiologists in 2011 and published in 2012. These updated guidelines are intended for use by anesthesiologists and individuals under the supervision of an anesthesiologist and may also serve as a resource for other physicians, nurses, or healthcare providers who manage patients with central venous catheters.Supplemental Digital Content is available in the text.

BACKGROUND: Difficult or failed intubation is a major contributor to morbidity for patients and liability for anesthesiologists. Updated difficult airway management guidelines and incorporation of new airway devices into practice may have affected patient outcomes. The authors therefore compared recent malpractice claims related to difficult tracheal intubation to older claims using the Anesthesia Closed Claims Project database. METHODS: Claims with difficult tracheal intubation as the primary damaging event occurring in the years 2000 to 2012 (n = 102) were compared to difficult tracheal intubation claims from 1993 to 1999 (n = 93). Difficult intubation claims from 2000 to 2012 were evaluated for preoperative predictors and appropriateness of airway management. RESULTS: Patients in 2000 to 2012 difficult intubation claims were sicker (78% American Society of Anesthesiologists [ASA] Physical Status III to V; n = 78 of 102) and had more emergency procedures (37%; n = 37 of 102) compared to patients in 1993 to 1999 claims (47% ASA Physical Status III to V; n = 36 of 93; P < 0.001 and…

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:…

Commercial applications of artificial intelligence and machine learning have made remarkable progress recently, particularly in areas such as image recognition, natural speech processing, language translation, textual analysis, and self-learning. Progress had historically languished in these areas, such that these skills had come to seem ineffably bound to intelligence. However, these commercial advances have performed best at single-task applications in which imperfect outputs and occasional frank errors can be tolerated.The practice of anesthesiology is different. It embodies a requirement for high reliability, and a pressured cycle of interpretation, physical action, and response rather than any single cognitive act. This review covers the basics of what is meant by artificial intelligence and machine learning for the practicing anesthesiologist, describing how decision-making behaviors can emerge from simple equations. Relevant clinical questions are introduced to illustrate how machine learning might help solve them-perhaps bringing anesthesiology into an era of…

BACKGROUND: Days alive and out of hospital is a potentially useful patient-centered quality measure for perioperative care in adult surgical patients. However, there has been very limited prior validation of this endpoint with respect to its ability to capture differences in patient-level risk factor profiles and longer-term postoperative outcomes. The main objective of this study was assessment of the feasibility and validity of days alive and out of hospital as a patient-centered outcome for perioperative medicine. METHODS: The authors evaluated 540,072 adults undergoing 1 of 12 major elective noncardiac surgical procedures between 2006 to 2014. Primary outcome was days alive and out of hospital at 30 days, secondary outcomes were days alive and out of hospital at 90 days and 180 days. Unadjusted and risk-adjusted adjusted analyses were used to determine the association of days alive and out of hospital with patient-, surgery-, and hospital-level characteristics. Patients with days alive and out of hospital at 30 days values less than the tenth percentile were also classified as…

A moderately liberal IV fluid regimen, using a balanced crystalloid, and consideration of the use of an advanced hemodynamic monitor in a setting of an enhanced recovery pathway are recommended for major surgery. Supplemental Digital Content is available in the text.

In this narrative review article, the authors discuss the anatomy, nomenclature, history, approaches (posterior vs. lateral vs. subcostal), techniques, pharmacology, indications, and complications of transversus abdominis plane blocks, as well as possible alternative truncal blocks.Despite the scarcity of evidence and contradictory findings, certain clinical suggestions can nonetheless be made. Overall transversus abdominis plane blocks appear most beneficial in the setting of open appendectomy (posterior or lateral approach). Lateral transversus abdominis plane blocks are not suggested for laparoscopic hysterectomy, laparoscopic appendectomy, or open prostatectomy. However, transversus abdominis plane blocks could serve as an analgesic option for Cesarean delivery (posterior or lateral approach) and open colorectal section (subcostal or lateral approach) if there exist contraindications to intrathecal morphine and thoracic epidural analgesia, respectively.Future investigation is required to compare posterior and subcostal transversus abdominis plane blocks in clinical settings.…

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Driving pressure (plateau minus end-expiratory airway pressure) is a target in patients with acute respiratory distress syndrome, and is proposed as a target during general anesthesia for patients with normal lungs. It has not been reported for thoracic anesthesia where isolated, inflated lungs may be especially at risk. WHAT THIS ARTICLE TELLS US THAT IS NEW: In a double-blinded, randomized trial (292 patients), minimized driving pressure compared with standard protective ventilation was associated with less postoperative pneumonia or acute respiratory distress syndrome. BACKGROUND: Recently, several retrospective studies have suggested that pulmonary complication is related with driving pressure more than any other ventilatory parameter. Thus, the authors compared driving pressure-guided ventilation with conventional protective ventilation in thoracic surgery, where lung protection is of the utmost importance. The authors hypothesized that driving pressure-guided ventilation decreases postoperative pulmonary complications more than…

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 components with myocardial and kidney injury after noncardiac surgery. METHODS: The authors included 23,140 noncardiac surgery patients at Cleveland Clinic who had blood pressure recorded at 1-min intervals from radial arterial catheters. The authors used univariable smoothing and multivariable logistic regression to estimate probabilities of each outcome as function of patients' lowest pressure for a cumulative 5 min for each component, comparing discriminative ability using C-statistics. The authors further assessed the association between outcomes and both area and minutes under derived thresholds corresponding to the beginning of increased risk for the average patient. RESULTS: Out of 23,140 patients analyzed, myocardial injury occurred in 6.1% and acute kidney injury in 8.2%. Based on the…

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…

BACKGROUND: Compared with historic ventilation strategies, modern lung-protective ventilation includes lower tidal volumes (VT), lower driving pressures, and application of positive end-expiratory pressure (PEEP). The contributions of each component to an overall intraoperative protective ventilation strategy aimed at reducing postoperative pulmonary complications have neither been adequately resolved, nor comprehensively evaluated within an adult cardiac surgical population. The authors hypothesized that a bundled intraoperative protective ventilation strategy was independently associated with decreased odds of pulmonary complications after cardiac surgery. METHODS: In this observational cohort study, the authors reviewed nonemergent cardiac surgical procedures using cardiopulmonary bypass at a tertiary care academic medical center from 2006 to 2017. The authors tested associations between bundled or component intraoperative protective ventilation strategies (VT below 8 ml/kg ideal body weight, modified driving pressure [peak inspiratory pressure - PEEP] below 16 cm H2O, and PEEP…

BACKGROUND: Compared with neuraxial anesthesia, general anesthesia for cesarean delivery is associated with increased risk of maternal adverse events. Reducing avoidable general anesthetics for cesarean delivery may improve safety of obstetric anesthesia care. This study examined adverse events, trends, and factors associated with potentially avoidable general anesthetics for cesarean delivery. METHODS: This retrospective study analyzed cesarean delivery cases without a recorded indication for general anesthesia or contraindication to neuraxial anesthesia in New York State hospitals, 2003 to 2014. Adverse events included anesthesia complications (systemic, neuraxial-related, and drug-related), surgical site infection, venous thromboembolism, and the composite of death or cardiac arrest. Anesthesia complications were defined as severe if associated with death, organ failure, or prolonged hospital stay. RESULTS: During the study period, 466,014 cesarean deliveries without a recorded indication for general anesthesia or contraindication to neuraxial anesthesia were analyzed; 26,431…

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…

BACKGROUND: Intraoperative and postoperative hypotension are associated with myocardial and kidney injury and 30-day mortality. Intraoperative blood pressure is measured frequently, but blood pressure on surgical wards is usually measured only every 4 to 6 h, leaving long intervals during which hypotension and hypertension may be undetected. This study evaluated the incidence and severity of postoperative hypotension and hypertension in adults recovering from abdominal surgery and the extent to which serious perturbations were missed by routine vital-sign assessments. METHODS: Blood pressure was recorded at 1-min intervals during the initial 48 h in adults recovering from abdominal surgery using a continuous noninvasive monitor. Caregivers were blinded to these measurements and depended on routine vital-sign assessments. Hypotension and hypertension were characterized as time under and above various mean arterial pressure thresholds. RESULTS: Of 502 available patients, 312 patients with high-quality records were analyzed, with a median measurement time of 48 [interquartile range:…

The incidence of surgical complications has remained largely unchanged over the past two decades. Inherent complexity in surgery, new technology possibilities, increasing age and comorbidity in patients may contribute to this. Surgical safety checklists may be used as some of the tools to prevent such complications. Use of checklists may reduce critical workload by eliminating issues that are already controlled for. The global introduction of the World Health Organization Surgical Safety Checklist aimed to improve safety in both anesthesia and surgery and to reduce complications and mortality by better teamwork, communication, and consistency of care. This review describes a literature synthesis on advantages and disadvantages in use of surgical safety checklists emphasizing checklist development, implementation, and possible clinical effects and using a theoretical framework for quality of provided healthcare (structure-process-outcome) to understand the checklists' possible impact on patient safety.

BACKGROUND: Interscalene nerve blockade remains one of the most commonly used anesthetic and analgesic approaches for shoulder surgery. The high incidence of hemidiaphragmatic paralysis associated with the block, however, precludes its use among patients with compromised pulmonary function. To address this issue, recent studies have investigated phrenic-sparing alternatives that provide analgesia. None, however, have been able to reliably demonstrate surgical anesthesia without significant risk for hemidiaphragmatic paralysis. The utility of the superior trunk block has yet to be studied. The hypothesis was that compared with the interscalene block, the superior trunk block will provide noninferior surgical anesthesia and analgesia while sparing the phrenic nerve. METHODS: This randomized controlled trial included 126 patients undergoing arthroscopic ambulatory shoulder surgery. Patients either received a superior trunk block (n = 63) or an interscalene block (n = 63). The primary outcomes were the incidence of hemidiaphragmatic paralysis and worst pain score in the recovery room.…

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Rapid response to witnessed, pulseless cardiac arrest is associated with increased survival. WHAT THIS ARTICLE TELLS US THAT IS NEW: Assessment of witnessed, pulseless cardiac arrests occurring at 538 hospitals during a 9-yr period indicates that CPR did not occur immediately at 0 min in 5.7% of patients despite guidelines for instantaneous initiation. Delay in initiation of CPR was associated with significantly decreased survival.Time to initiation of CPR and subsequent time to initiation of administration of defibrillation shock (for shockable arrhythmias) and epinephrine were both associated with reduced patient survival. BACKGROUND: Because the extent to which delays in initiating cardiopulmonary resuscitation (CPR) versus the time from CPR to defibrillation or epinephrine treatment affects survival remains unknown, it was hypothesized that all three independently decrease survival in in-hospital cardiac arrest. METHODS: Witnessed, index cases of cardiac arrest from the Get With The Guidelines-Resuscitation Database occurring between 2000…

C oncern over the potential for lung injury due to mechanical ventilation has fueled investigations on lung protection in the operating room.[1][2][3] Based on the intensive care literature, 4 tidal volume (V T ) and positive end-expiratory pressure (PEEP) settings have been the focus of intraoperative clinical trials.[1][2][3] Recent results in acute respiratory distress syndrome (ARDS) 5 and surgical patients 6,7 have suggested that the benefits associated with V T and PEEP settings are mediated by driving pressures.As our understanding of the physical and biologic effects of mechanical ventilation evolves, the concepts of driving pressure and transpulmonary pressure have been increasingly used to quantify the mechanical forces acting over the lungs during mechanical ventilation and to guide clinical care.In this perspective, we discuss the definition of those concepts, their measurement in the clinical setting, their interpretation, and their use in typical scenarios.This article is featured in "This Month in Anesthesiology," page 1A.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Higher driving pressure during controlled mechanical ventilation is known to be associated with increased mortality in patients with acute respiratory distress syndrome.Whereas patients with acute respiratory distress syndrome are initially managed with controlled mechanical ventilation, as they improve, they are transitioned to assisted ventilation. Whether higher driving pressure assessed during pressure support (assisted) ventilation can be reliably assessed and whether higher driving pressure is associated with worse outcomes in patients with acute respiratory distress syndrome has not been well studied. WHAT THIS ARTICLE TELLS US THAT IS NEW: This study shows that in the majority of adult patients with acute respiratory distress syndrome, both driving pressure and respiratory system compliance can be reliably measured during pressure support (assisted) ventilation.Higher driving pressure measured during pressure support (assisted) ventilation significantly associates with increased intensive care unit mortality, whereas peak inspiratory…

Clinical Trials examining the effect of intraoperative Methadone on Postoperative outcomesIn 1982, Gourlay et al. 6 published a small study describing the effect of a single dose of methadone, administered at induction of anesthesia, on postoperative pain scores and analgesic requirements.Since this initial publication,

Over the past decade, failure to rescue-defined as the death of a patient after one or more potentially treatable complications-has received increased attention as a surgical quality indicator. Failure to rescue is an appealing quality target because it implicitly accounts for the fact that postoperative complications may not always be preventable and is based on the premise that prompt recognition and treatment of complications is a critical, actionable point during a patient's postoperative course. Although numerous patient and macrosystem factors have been associated with failure to rescue, there is an increasing appreciation of the key role of microsystem factors. Although failure to rescue is believed to contribute to observed hospital-level variation in both surgical outcomes and costs, further work is needed to delineate the underlying patient-level and system-level factors preventing the timely identification and treatment of postoperative complications. Therefore, the goals of this narrative review are to provide a conceptual framework for understanding failure to rescue,…

BACKGROUND: Postoperative delirium is one of the most common complications in the elderly surgical population. However, its long-term outcomes remain largely to be determined. Therefore a prospective cohort study was conducted to determine the association between postoperative delirium and long-term decline in activities of daily living and postoperative mortality. The hypothesis in the present study was that postoperative delirium was associated with a greater decline in activities of daily living and higher mortality within 24 to 36 months after anesthesia and surgery. METHODS: The participants (at least 65 yr old) having the surgeries of (1) proximal femoral nail, (2) hip replacement, or (3) open reduction and internal fixation under general anesthesia were enrolled. The Confusion Assessment Method algorithm was administered to diagnose delirium before and on the first, second, and fourth days after the surgery. Activities of daily living were evaluated by using the Chinese version of the activities of daily living scale (range, 14 to 56 points), and preoperative cognitive…

BACKGROUND: This repeated cross-sectional survey study was conducted to determine the prevalence of, and factors associated with, burnout, distress, and depression among anesthesiology residents and first-year graduates. We hypothesized that heavy workload and student debt burden were associated with a higher risk of physician burnout, distress, and depression, and that perception of having adequate workplace resources, work-life balance, and social support were associated with a lower risk. METHODS: Physicians beginning U.S. anesthesiology residency between 2013 and 2016 were invited to take online surveys annually from their clinical anesthesia year 1 to 1 yr after residency graduation. The Maslach Burnout Inventory, the Physician Well-Being Index, and the Harvard Department of Psychiatry/National Depression Screening Day Scale were used to measure burnout, distress, and depression, respectively. Logistic regression analyses were conducted to examine whether self-reported demographics, personal, and professional factors were associated with the risk of burnout, distress, and…

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…

BACKGROUND: Interscalene brachial plexus block of the C5-C6 roots provides highly effective postoperative analgesia after shoulder surgery but usually results in hemidiaphragmatic paresis. Injection around the superior trunk of the brachial plexus is an alternative technique that may reduce this risk. The authors hypothesized that the superior trunk block would provide noninferior postoperative analgesia compared with the interscalene block and reduce hemidiaphragmatic paresis. METHODS: Eighty patients undergoing arthroscopic shoulder surgery were randomized to receive a preoperative injection of 15 ml of 0.5% ropivacaine and 5 μg · ml epinephrine around either (1) the C5-C6 nerve roots (interscalene block group) or (2) the superior trunk (superior trunk block group). The primary outcome was pain intensity 24 h after surgery measured on an 11-point numerical rating score; the prespecified noninferiority limit was 1. Diaphragmatic function was assessed using both ultrasonographic measurement of excursion and incentive spirometry by a blinded investigator before and 30 min after block…

Qualitative research was originally developed within the social sciences. Medical education is a field that comprises multiple disciplines, including the social sciences, and utilizes qualitative research to gain a broader understanding of key phenomena within the field. Many clinician educators are unfamiliar with qualitative research. This article provides a primer for clinician educators who want to appraise or conduct qualitative research in medical education. This article discusses a definition and the philosophical underpinnings for qualitative research. Using the Standards for Reporting Qualitative Research as a guide, this article provides a step-wise approach for conducting and evaluating qualitative research in medical education. This review will enable the reader to understand when to utilize qualitative research in medical education and how to interpret reports using qualitative approaches.

BACKGROUND: Cognitive changes after anesthesia and surgery represent a significant public health concern. We tested the hypothesis that, in patients 60 yr or older scheduled for noncardiac surgery, automated management of anesthetic depth, cardiac blood flow, and protective lung ventilation using three independent controllers would outperform manual control of these variables. Additionally, as a result of the improved management, patients in the automated group would experience less postoperative neurocognitive impairment compared to patients having standard, manually adjusted anesthesia. METHODS: In this single-center, patient-and-evaluator-blinded, two-arm, parallel, randomized controlled, superiority study, 90 patients having noncardiac surgery under general anesthesia were randomly assigned to one of two groups. In the control group, anesthesia management was performed manually while in the closed-loop group, the titration of anesthesia, analgesia, fluids, and ventilation was performed by three independent controllers. The primary outcome was a change in a cognition score (the…

BACKGROUND: Methadone is a long-acting opioid that has been reported to reduce postoperative pain scores and analgesic requirements and may attenuate development of chronic postsurgical pain. The aim of this secondary analysis of two previous trials was to follow up with patients who had received a single intraoperative dose of either methadone or traditional opioids for complex spine or cardiac surgical procedures. METHODS: Preplanned analyses of long-term outcomes were conducted for spinal surgery patients randomized to receive 0.2 mg/kg methadone at the start of surgery or 2 mg hydromorphone at surgical closure, and for cardiac surgery patients randomized to receive 0.3 mg/kg methadone or 12 μg/kg fentanyl intraoperatively. A pain questionnaire assessing the weekly frequency (the primary outcome) and intensity of pain was mailed to subjects 1, 3, 6, and 12 months after surgery. Ordinal data were compared with the Mann-Whitney U test, and nominal data were compared using the chi-square test or Fisher exact probability test. The criterion for rejection of the null hypothesis was P…

BACKGROUND: Airway closure causes lack of communication between proximal airways and alveoli, making tidal inflation start only after a critical airway opening pressure is overcome. The authors conducted a matched cohort study to report the existence of this phenomenon among obese patients undergoing general anesthesia. METHODS: Within the procedures of a clinical trial during gynecological surgery, obese patients underwent respiratory/lung mechanics and lung volume assessment both before and after pneumoperitoneum, in the supine and Trendelenburg positions, respectively. Among patients included in this study, those exhibiting airway closure were compared to a control group of subjects enrolled in the same trial and matched in 1:1 ratio according to body mass index. RESULTS: Eleven of 50 patients (22%) showed airway closure after intubation, with a median (interquartile range) airway opening pressure of 9 cm H2O (6 to 12). With pneumoperitoneum, airway opening pressure increased up to 21 cm H2O (19 to 28) and end-expiratory lung volume remained unchanged (1,294 ml [1,154 to 1,363]…

BACKGROUND: Human umbilical cord mesenchymal stromal cells possess considerable therapeutic promise for acute respiratory distress syndrome. Umbilical cord mesenchymal stromal cells may exert therapeutic effects via extracellular vesicles, while priming umbilical cord mesenchymal stromal cells may further enhance their effect. The authors investigated whether interferon-γ-primed umbilical cord mesenchymal stromal cells would generate mesenchymal stromal cell-derived extracellular vesicles with enhanced effects in Escherichia coli (E. coli) pneumonia. METHODS: In a university laboratory, anesthetized adult male Sprague-Dawley rats (n = 8 to 18 per group) underwent intrapulmonary E. coli instillation (5 × 10 colony forming units per kilogram), and were randomized to receive (a) primed mesenchymal stromal cell-derived extracellular vesicles, (b) naïve mesenchymal stromal cell-derived extracellular vesicles (both 100 million mesenchymal stromal cell-derived extracellular vesicles per kilogram), or (c) vehicle. Injury severity and bacterial load were assessed at 48 h. In vitro studies…

Abstract Editor’s Perspective What We Already Know about This Topic The nociception level index (Medasense Biometrics Ltd., Ramat Gan, Israel), is a reliable measure of moderate to intense noxious stimulation during anesthesia and surgery What This Article Tells Us That Is New In a randomized trial in patients having major abdominal surgery, compared to standard practice, nociception level-guided analgesia resulted in 30% less intraoperative remifentanil consumption Background The multidimensional index of nociception, the nociception level, outperforms blood pressure and heart rate in detection of nociceptive events during anesthesia. We hypothesized that nociception level–guided analgesia reduces opioid consumption and suboptimal anesthesia events such as low blood pressure and use of vasoactive medication. Methods In this single-blinded randomized study, 80 American Society of Anesthesiologists class I–III adult patients of either sex, scheduled for major abdominal procedures under remifentanil/propofol anesthesia by target-controlled infusion, were included. During the procedure…

BACKGROUND: Crystalloid solutions leave the circulation quickly, whereas colloids remain for hours, thus promoting hemodynamic stability. However, colloids are expensive and promote renal toxicity in critical care patients. This study tested the hypothesis that goal-directed colloid administration during elective abdominal surgery decreases 30-day major complications more than goal-directed crystalloid administration. METHODS: In this parallel-arm double-blinded multicenter randomized trial, adults having moderate- to high-risk open and laparoscopically assisted abdominal surgery with general anesthesia were randomly assigned to Doppler-guided intraoperative volume replacement with 6% hydroxyethyl starch 130/0.4 (n = 523) or lactated Ringer's solution (n = 534). The primary outcome was a composite of serious postoperative cardiac, pulmonary, infectious, gastrointestinal, renal, and coagulation complications that were assessed with a generalized estimating equation multivariate model. The primary safety outcome was a change in serum creatinine concentration up to 6 months…

Abstract Editor’s Perspective What We Already Know about This Topic Obesity increases the propensity to atelectasis in acute respiratory distress syndrome, but the optimal approach to reversing this atelectasis is uncertain What This Article Tells Us That Is New A clinical crossover study comparing three approaches to titrate positive end-expiratory pressure (PEEP; according to a fixed table, according to end-expiratory esophageal pressure, and targeting the best compliance during a decremental PEEP trial) found that a recruitment maneuver followed by decremental PEEP minimized atelectasis and overdistension, and best restored compliance and oxygenation without causing hemodynamic impairment Background Obese patients are characterized by normal chest-wall elastance and high pleural pressure and have been excluded from trials assessing best strategies to set positive end-expiratory pressure (PEEP) in acute respiratory distress syndrome (ARDS). The authors hypothesized that severely obese patients with ARDS present with a high degree of lung collapse, reversible by titrated PEEP…

BACKGROUND: There is a lack of consensus on how to manage anticoagulation during veno-venous extracorporeal membrane oxygenation, including antithrombin monitoring and supplementation. The authors' aim was to determine current practice in a large number of extracorporeal membrane oxygenation centers around the world. METHODS: This was an electronic survey disseminated in 2018 to directors and coordinators of extracorporeal membrane oxygenation centers as well as to extracorporeal membrane oxygenation experts. Participating centers were classified according to some covariates that may affect practice, including 2017 gross national income per capita, primary patient population, and annual extracorporeal membrane oxygenation patient volume. RESULTS: The authors analyzed 273 unique responses from 50 countries. Systemic anticoagulation was routinely prescribed in 264 (96.7%) centers, with unfractionated heparin being the drug of choice in 255 (96.6%) of them. The preferred method to monitor anticoagulation was activated partial thromboplastin time in 114 (41.8%) centers, activated…

BACKGROUND: Normal blood pressure varies among individuals and over the circadian cycle. Preinduction blood pressure may not be representative of a patient's normal blood pressure profile and cannot give an indication of a patient's usual range of blood pressures. This study therefore aimed to determine the relationship between ambulatory mean arterial pressure and preinduction, postinduction, and intraoperative mean arterial pressures. METHODS: Ambulatory (automated oscillometric measurements at 30-min intervals) and preinduction, postinduction, and intraoperative mean arterial pressures (1-min intervals) were prospectively measured and compared in 370 American Society of Anesthesiology physical status classification I or II patients aged 40 to 65 yr having elective noncardiac surgery with general anesthesia. RESULTS: There was only a weak correlation between the first preinduction and mean daytime mean arterial pressure (r = 0.429, P < 0.001). The difference between the first preinduction and mean daytime mean arterial pressure varied considerably among individuals. In about two…

BACKGROUND: Mechanisms of postoperative delirium remain poorly understood, limiting development of effective treatments. We tested the hypothesis that intraoperative oxidative damage is associated with delirium and neuronal injury and that disruption of the blood-brain barrier modifies these associations. METHODS: In a prespecified cohort study of 400 cardiac surgery patients enrolled in a clinical trial of atorvastatin to reduce kidney injury and delirium, we measured plasma concentrations of F2-isoprostanes and isofurans using gas chromatography-mass spectrometry to quantify oxidative damage, ubiquitin carboxyl-terminal hydrolase isozyme L1 to quantify neuronal injury, and S100 calcium-binding protein B using enzyme-linked immunosorbent assays to quantify blood-brain barrier disruption before, during, and after surgery. We performed the Confusion Assessment Method for the Intensive Care Unit twice daily to diagnose delirium. We measured the independent associations between intraoperative F2-isoprostanes and isofurans and delirium (primary outcome) and postoperative ubiquitin…

BACKGROUND: Pneumoperitoneum and a steep Trendelenburg position during robot-assisted laparoscopic prostatectomy have been demonstrated to promote a cranial shift of the diaphragm and the formation of atelectasis in the dorsal parts of the lungs. However, neither an impact of higher positive end-expiratory pressure (PEEP) on preserving the ventilation in the dorsal region nor its physiologic effects have been fully examined. The authors hypothesized that PEEP of 15 cm H2O during robot-assisted laparoscopic prostatectomy might maintain ventilation in the dorsal parts and thus improve lung mechanics. METHODS: In this randomized controlled study, 48 patients undergoing robot-assisted laparoscopic prostatectomy were included in the analysis. Patients were assigned to the conventional PEEP (5 cm H2O) group or the high PEEP (15 cm H2O) group. Regional ventilation was monitored using electrical impedance tomography before and after the establishment of pneumoperitoneum and 20° Trendelenburg position during the surgery. The primary endpoint was the regional ventilation in the dorsal parts…

Operating room fires are rare but devastating events. Guidelines are available for the prevention and management of surgical fires; however, these recommendations are based on expert opinion and case series. The three components of an operating room fire are present in virtually all surgical procedures: an oxidizer (oxygen, nitrous oxide), an ignition source (i.e., laser, "Bovie"), and a fuel. This review analyzes each fire ingredient to determine the optimal clinical strategy to reduce the risk of fire. Surgical checklists, team training, and the specific management of an operating room fire are also reviewed.

BACKGROUND: Sepsis and septic shock are severe inflammatory conditions related to high morbidity and mortality. We performed a systematic review with meta-analysis of randomized trials to assess whether extracorporeal blood purification reduces mortality in this setting. METHODS: Electronic databases were searched for pertinent studies up to January 2019. We included randomized controlled trials on the use of hemoperfusion, hemofiltration without a renal replacement purpose, and plasmapheresis as a blood purification technique in comparison to conventional therapy in adult patients with sepsis and septic shock. The primary outcome was mortality at the longest follow-up available. We calculated relative risks and 95% CIs. The grading of recommendations assessment, development and evaluation methodology for the certainty of evidence was used. RESULTS: Thirty-seven trials with 2,499 patients were included in the meta-analysis. Hemoperfusion was associated with lower mortality compared to conventional therapy (relative risk = 0.88 [95% CI, 0.78 to 0.98], P = 0.02, very low certainty…

BACKGROUND: A key feature of the human brain is its capability to adapt flexibly to changing external stimuli. This capability can be eliminated by general anesthesia, a state characterized by unresponsiveness, amnesia, and (most likely) unconsciousness. Previous studies demonstrated decreased connectivity within the thalamus, frontoparietal, and default mode networks during general anesthesia. We hypothesized that these alterations within specific brain networks lead to a change of communication between networks and their temporal dynamics. METHODS: We conducted a pooled spatial independent component analysis of resting-state functional magnetic resonance imaging data obtained from 16 volunteers during propofol and 14 volunteers during sevoflurane general anesthesia that have been previously published. Similar to previous studies, mean z-scores of the resulting spatial maps served as a measure of the activity within a network. Additionally, correlations of associated time courses served as a measure of the connectivity between networks. To analyze the temporal dynamics of…

BACKGROUND: Neutrophil extracellular traps have been associated with tissue damage. Whether these are involved in the pathogenesis of human acute respiratory distress syndrome (ARDS) and could be a potential therapeutic target is unknown. The authors quantified bronchoalveolar and blood neutrophil extracellular traps in patients with pneumonia-related ARDS and assessed their relationship with ventilator-free days. METHODS: Immunocompetent patients with pneumonia and moderate or severe ARDS (n = 35) and controls (n = 4) were included in a prospective monocentric study. Neutrophil extracellular trap concentrations were quantified (as DNA-myeloperoxidase complexes) in bronchoalveolar lavage fluid and serum by enzyme-linked immunosorbent assay. The relationship between bronchoalveolar lavage neutrophil extracellular trap concentrations and the primary clinical endpoint (i.e., the number of live ventilator-free days at day 28) was assessed using linear regression analyses. RESULTS: There was no significant relationship between bronchoalveolar lavage neutrophil extracellular trap…

BACKGROUND: Thoracic paravertebral block is the preferred regional anesthetic technique for breast cancer surgery, but concerns over its invasiveness and risks have prompted search for alternatives. Pectoralis-II block is a promising analgesic technique and potential alternative to paravertebral block, but evidence of its absolute and relative effectiveness versus systemic analgesia (Control) and paravertebral block, respectively, is conflicting. This meta-analysis evaluates the analgesic effectiveness of Pectoralis-II versus Control and paravertebral block for breast cancer surgery. METHODS: Databases were searched for breast cancer surgery trials comparing Pectoralis-II with Control or paravertebral block. Postoperative oral morphine consumption and difference in area under curve for pooled rest pain scores more than 24 h were designated as coprimary outcomes. Opioid-related side effects, effects on long-term outcomes, such as chronic pain and opioid dependence, were also examined. Results were pooled using random-effects modeling. RESULTS: Fourteen randomized trials (887…

A narrative review of the pathophysiology, diagnosis, management, delivery implications, obstetric anesthesia care, and potential critical care needs in patients presenting with acute fatty liver of pregnancy.

This practice advisory updates the “Practice Advisory for the Perioperative Management of Patients with Cardiac Implantable Electronic Devices: Pacemakers and Implantable Cardioverter–Defibrillators: An Updated Report by the American Society of Anesthesiologists Task Force on Perioperative Management of Patients with Cardiac Implantable Electronic Devices,” adopted by the American Society of Anesthesiologists in 2010 and published in 2011. This updated advisory is intended for use by anesthesiologists and all other individuals who deliver or who are responsible for anesthesia care. The update may also serve as a resource for other physicians and healthcare professionals who manage patients with cardiac implantable electronic devices.Supplemental Digital Content is available in the text.

BACKGROUND: Persistent postsurgical pain is common and affects quality of life. The hypothesis was that use of pregabalin and ketamine would prevent persistent pain after cardiac surgery. METHODS: This randomized, double-blind, placebo-controlled trial was undertaken at two cardiac surgery centers in the United Kingdom. Adults without chronic pain and undergoing any elective cardiac surgery patients via sternotomy were randomly assigned to receive either usual care, pregabalin (150 mg preoperatively and twice daily for 14 postoperative days) alone, or pregabalin in combination with a 48-h postoperative infusion of intravenous ketamine at 0.1 mg · kg · h. The primary endpoints were prevalence of clinically significant pain at 3 and 6 months after surgery, defined as a pain score on the numeric rating scale of 4 or higher (out of 10) after a functional assessment of three maximal coughs. The secondary outcomes included acute pain, opioid use, and safety measures, as well as long-term neuropathic pain, analgesic requirement, and quality of life. RESULTS: In total, 150 patients were…