This Month in Anesthesiology

431 Trends in Use of Medications for Opioid Use Disorder among Commercially Insured U.S. Surgical Patients, 2016 to 2022Image: A. Johnson, Vivo Visuals Studio.Medications such as buprenorphine, naltrexone, and methadone can improve outcomes for individuals with opioid use disorder. Medications for opioid use disorder have implications for perioperative management, since they may affect the effectiveness of some perioperative pain treatments. In a national database that included 8,137,973 surgical cases, the adjusted prevalence of medication use for opioid disorder increased by 80% from 2016 to 2022, from 55.2 per 100,000 to 99.8 per 100,000. Medication use for opioid disorder was most common among patients undergoing wound debridement and orthopedic surgical procedures. See the accompanying Editorial on page 266. 289 Pain as a Driver of Myocardial Injury in Hip Fracture Patients: A Hip Fracture Accelerated Surgical Treatment and Care Track (HIP ATTACK) Trial Secondary AnalysisImage: J. P. Rathmell.Pain activates the sympathetic nervous system, potentially influencing myocardial oxygen demand through changes in blood pressure and heart rate. Among 2,430 patients with hip fracture who were enrolled in a multicenter study, patients experiencing moderate or severe pain before or after surgery had an increased odds of troponin elevation due to any cause, myocardial injury without infarction, and a composite outcome of myocardial injury or infarction. Further research is needed to understand the potential for pain treatment interventions to improve perioperative cardiac outcomes. See the accompanying Editorial on page 257. 301 Efficacy and Safety of Preemptive Magnesium Sulfate Infusion during Pheochromocytoma and Paraganglioma Resection: A Randomized, Double-blind, Placebo-controlled TrialImage: J. P. Rathmell.Magnesium supplementation has often been used to treat hemodynamic fluctuations in a variety of perioperative settings, often with limited supporting data. This randomized, double-blind, single-center trial utilized a loading dose and continuous infusion of magnesium sulfate started 30 min before surgery and discontinued at the time of complete tumor resection evaluating a primary composite efficacy outcome of intraoperative hemodynamic instability as a percentage of the total duration of anesthesia. Supplementation significantly reduced the primary outcome without difference in any of the safety outcomes between groups. See the accompanying Editorial on page 260. 314 Intraoperative Cardiac Events in Pediatric Patients with Congenital Heart Disease Undergoing Noncardiac Procedures: Analysis of a Large Multicenter RegistryImage: Adobe Stock.There is a steady rise in the total number of encounters for noncardiac surgical interventions for patients with congenital heart disease. In this first large multicenter cohort of children with congenital heart disease having noncardiac surgery, risk factors for intraoperative cardiac events included the severity of the congenital heart disease, the need for an emergency procedure, and the presence of a respiratory comorbidity and/or respiratory illness. 325 Neonatal Outcomes with Regional versus General Anesthesia for Cesarean Delivery: A Meta-analysis of Randomized Controlled TrialsImage: J. P. Rathmell.One in three deliveries in the United States is by cesarean delivery. Neonatal outcomes are an important factor influencing choice of anesthetic technique. This meta-analysis included 36 randomized controlled trials with 3,456 neonates, comparing regional versus general anesthesia for cesarean delivery. Regional anesthesia (spinal, epidural, or combined spinal–epidural) is associated with slightly higher Apgar scores at 1 and 5 min compared with general anesthesia. Regional anesthesia was associated with reduced need for respiratory support but no significant difference in neonatal intensive care unit admission (wide CI). Evidence beyond the first hours of life is limited; further research is needed to clarify longer-term neurologic outcomes, neonatal intensive care unit care utilization, and mortality. 419 Relationship between Ventilation/Perfusion Ratio Mismatch and Capnogram Phase III Slope in Acute Bronchoconstriction and Its Modulation by Salbutamol Assessed by Synchrotron Imaging in Rabbit LungImage: From original article.Synchrotron radiation imaging allows quantitative evaluation of the distribution of lung ventilation, blood volume, and tissue morphology at a subacinar spatial resolution. Using methacholine to induce bronchospasm (causing ventilation defects) followed by salbutamol in this rabbit model, the authors demonstrated that phase III is determined not only by ventilation heterogeneity but also by ventilation/perfusion heterogeneity. Although salbutamol improved respiratory elastance, a lack of improvement (or worsening) in gas exchange is likely due to increased perfusion of low VA/Q̇ regions and increased shunt fraction. See the accompanying Editorial on page 263. 461 Cardiac Tamponade: Impact of Pathophysiology on Clinical PracticeImage: From original article.Cardiac tamponade and constrictive pericarditis are pericardial compressive syndromes of the myocardium. This review of cardiac tamponade correlates animal and human research, case reports, and theories into a present-day understanding of the pathophysiology of the disease and assists anesthesiologists with the clinical management of these patients, including controversial areas like positive-pressure ventilation and the effectiveness of chest compressions during cardiopulmonary resuscitation (CPR). 473 Emerging Role of Electroencephalographic Aperiodic Activity in Anesthesia: A Narrative ReviewImage: J. P. Rathmell.Recently, interest in the functional role of the aperiodic activity of the electroencephalographic signal has increased both in neuroscience and in anesthesiology. This narrative review aims to provide clinicians and researchers with practical and methodologic insights into characterizing aperiodic electroencephalographic activity, focusing on its neurophysiologic significance in neuroscience and anesthesia. It furthermore provides the reader with observed variations of aperiodic activity and periodic activity during general anesthesia and highlights whether those parameters could be useful to infer cognitive frailty and perioperative neurocognitive disorders and monitor depth of anesthesia during surgery.