Anesthesiology

The impact of frailty and sarcopenia on patient outcomes after complex spine surgery Purpose of review Frailty and sarcopenia represent a state of increased fragility and decreased reserve, and both have been associated with worse outcomes after surgery. The present review focuses on the definitions and measurement tools used to assess frailty and sarcopenia in patients with spinal disorder, and the relationships between frailty, sarcopenia, and postoperative outcomes in patients undergoing complex spine surgery. Recent findings Complex spine surgery is associated with a high rate of adverse events when using a validated, prospective data collection system. Recent studies have demonstrated that patients with spine surgery with frailty and sarcopenia have a higher risk of adverse events, although this relationship varies depending on the measurement tool and specific population studied. Both general and specific frailty assessment tools have been used in the spine surgery population, however the optimal tool is not known. Spinal disorders such as lumbar stenosis contribute to the frailty phenotype, and may be reversible with surgery. Summary Frailty and sarcopenia are increasingly recognized as important predictors of adverse outcomes after complex spine surgery. The optimal tool to measure frailty and sarcopenia in patients with spinal disorders remains unclear, and the role of surgery as an intervention to reverse frailty requires further investigation. Correspondence to Dr Alana M. Flexman, Department of Anesthesiology and Perioperative Care, Vancouver General Hospital, Room 2449 JPP 899 West 12th Avenue, Vancouver, BC, Canada, V5Z 1M9. Tel: +1 604 875 4304; fax: +1 604 875 5209; e-mail: alana.flexman@vch.ca Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Monitoring standards in sedation and analgesia: the odyssey of capnography in sedation for gastroenterology procedures Purpose of review Capnography is an excellent tool for early detection of hypoxemia and apnea in patients undergoing sedation for gastrointestinal endoscopy. The current American Society of Anesthesiology (ASA) guidelines recommend the use of capnography in any patient undergoing moderate sedation. The purpose of this review was to compile the most recent data available on capnography use in gastrointestinal endoscopy with the focus primarily on the use of capnography in moderate sedation cases. Recent findings Recent high-quality studies have evaluated the utility of capnography in low risk patients undergoing moderate sedation and have found no benefit with addition of capnography. Summary Capnography is beneficial when used for patients who are at a higher risk for sedation-related complications. There is no benefit when capnography is used in low risk patients undergoing routine upper endoscopy and colonoscopy under moderate sedation but there is benefit when used in advanced endoscopic procedures that require deeper sedation and have longer procedure times. Correspondence to John J. Vargo, MD, MPH, Director, Endoscopy Operations Enterprise, Digestive Disease Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA. Tel: +1 216 445 5012; e-mail: vargoj@ccf.org Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Safety in the nonoperating room anesthesia suite is not an accident: lessons from the National Transportation Safety Board Purpose of review To review the findings of National Transportation Safety Board-related airline near misses and catastrophes and apply these principles to the nonoperating room anesthesia (NORA) suite. Recent findings NORA is a specialty that has seen tremendous growth. In 2019, NORA contributes to a larger proportion of anesthesia practice than ever before. With this growth, the NORA anesthesiologist and team are challenged to provide safe, high-quality care for more patients, often with complex comorbidities, and are forced to utilize deeper levels of sedation and anesthesia than ever before. These added pressures create new avenues for human error and adverse outcomes. Summary Safety in modern anesthesia practice often draws comparison to the aviation industry. From distinct preoperational checklists, defined courses of action, safety monitoring and the process of guiding individuals through a journey, there are many similarities between the practice of anesthesia and flying an airplane. Consistent human performance is paramount to creating safe outcomes. Although human errors are inevitable in any complex process, the goal for both the pilot and physician is to ensure the safety of their passengers and patients, respectively. As the airline industry has had proven success at managing human error with a dramatic improvement in safety, a deeper look at several key examples will allow for comparisons of how to implement these strategies to improve NORA safety. Correspondence to Jason D. Walls, MD, Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA. Tel: +1 215 662 3773; e-mail: jason.walls@uphs.upenn.edu Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Transfusion in adults and children undergoing neurosurgery: the outcome evidence Purpose of review Transfusion is a common practice during neurosurgery. However, there is no evidence-based consensus on transfusion practice in neurosurgery. This review summarizes the evidence pertinent to the commonly used transfusion triggers in neurosurgical patients. Recent findings In the field of neurosurgery, there is only one randomized controlled trial, performed in patients with traumatic brain injury, to investigate the transfusion trigger of red blood cells. There is a lack-of-quality evidence pertinent to the transfusion triggers of other blood products. Most of the transfusion triggers used for neurosurgical patients are extrapolated from the evidence based on studies performed in nonneurosurgical patients. Clinical experience and expert opinions have played a major role in transfusion practice in neurosurgery. Summary There is a scarcity of high-quality outcome-based evidence for transfusion practice in neurosurgery. In the absence of quality evidence, the transfusion practice in neurosurgical patients should be based on the understanding of the complex pathophysiology related to anemia and coagulopathy and the balance between the risks and benefits associated with blood product transfusion. The practice guided by tissue oximeter and viscoelastic tests appears promising, but needs to be validated by future studies. Correspondence to Tianlong Wang, MD, PhD, Department of Anesthesiology, Xuanwu Hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China. Tel: +86 139 1052 5304; e-mail: w_tl5595@hotmail.com Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Do you remember ‘supply and demand’? No abstract available

Neurological complications after cardiac surgery: anesthetic considerations based on outcome evidence Purpose of review Neurological complications after cardiac surgery remain prevalent. This review aims to discuss the modifiable and outcome-relevant risk factors based on an up-to-date literature review, with a focus on interventions that may improve outcomes. Recent findings There is a close relationship between intraoperative blood pressure and postoperative neurological outcomes in cardiac surgical patients based on cohort studies and randomized controlled trials. Adopting an optimal and personalized blood pressure target is essential; however, the outstanding issue is the determination of this target. Maintaining cerebral tissue oxygen saturation at least 90% patient's baseline during cardiac surgery may be beneficial; however, the outstanding issues are effective intervention protocols and quality outcome evidence. Maintaining hemoglobin at least 7.5 g/dl may be adequate for cardiac surgical patients; however, this evidence is based on the pooled results of thousands of patients. We still need to know the optimal hemoglobin level for an individual patient, which is of particular relevance during the decision-making of transfusion or not. Summary The available evidence highlights the importance of maintaining optimal and individualized blood pressure, cerebral tissue oxygen saturation and hemoglobin level in improving neurological outcomes after cardiac surgery. However, outstanding issues remain and need to be addressed via outcome-oriented further research. Correspondence to Wei Mei, MD, Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Road, Wuhan 430030, China. Tel: +86 27 83662673; e-mail: wmei@hust.edu.cn Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Anesthesia and brain tumor surgery: technical considerations based on current research evidence Purpose of review Anesthetics may influence cancer recurrence and metastasis following surgery by modulating the neuroendocrine stress response or by directly affecting cancer cell biology. This review summarizes the current evidence on whether commonly used anesthetics potentially affect postoperative outcomes following solid organ cancer surgery with particular focus on neurological malignancies. Recent findings Despite significant improvement in diagnostic and therapeutic technology over the past decades, mortality rates after cancer surgery (including brain tumor resection) remains high. With regards to brain tumors, interaction between microglia/macrophages and tumor cells by multiple biological factors play an important role in tumor progression and metastasis. Preclinical studies have demonstrated an association between anesthetics and brain tumor cell biology, and a potential effect on tumor progression and metastasis has been revealed. However, in the clinical setting, the current evidence is inadequate to draw firm conclusions on the optimal anesthetic technique for brain tumor surgery. Summary Further work at both the basic science and clinical level is urgently needed to evaluate the association between perioperative factors, including anesthetics/technique, and postoperative brain tumor outcomes. Correspondence to Daqing Ma, Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital 369 Fulham Road, London SW10 9NH, UK. Tel: +44 203315 8495; fax: +44 203315 5109; e-mail: d.ma@imperial.ac.uk Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Neuroanesthesia and outcomes: evidence, opinions, and speculations on clinically relevant topics Purpose of review The objective of this review is to identify outstanding topics most relevant to neuroanesthesia practice and patient outcomes. We discuss the role of awake craniotomy, choice of general anesthetic agents, monitoring of anesthetic ‘depth’, mannitol-induced diuresis, neurophysiological monitoring, hyperventilation, and cerebral hypoperfusion. Recent findings Awake craniotomy, although a technique likely underused, is associated with enhanced recovery after surgery and prolonged survival after brain tumor resection compared with surgery under general anesthesia. The choice of general anesthetic must balance patient and surgical factors. Although propofol may be associated with favorable oncologic outcomes, currently available retrospective evidence does not specifically address neurosurgical patients. Both the definition and monitoring of anesthetic ‘depth’ remains elusive. Neuroanesthesiologists need to recognize and manage intraoperative light anesthesia in a timely fashion. Further evidence related to the optimal management of mannitol-induced diuresis and hyperventilation in neurosurgical patients is needed. Contemporary neurophysiological monitoring can reasonably detect intraoperative neurologic injury; however, its effect on patient outcome is unclear. Finally, cerebral hypoperfusion without stroke may be common; however, the clinical significance requires further investigation. Summary We provide an overview of several topics that are relevant to neuroanesthesia practice and patient outcomes based on evidence, opinions, and speculations. Our review highlights the need for further outcome-oriented studies to specifically address these clinically relevant issues. Correspondence to Lingzhong Meng, MD, Professor and Division Chief, Department of Anesthesiology, Yale University School of Medicine, 333 Cedar Street, TMP 3, PO Box 208051, New Haven, CT 06520, USA. Tel: +1 203 785 2802; e-mail: lingzhong.meng@yale.edu Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Anaesthesia for stroke thrombectomy: technical considerations based on outcome evidence Purpose of review Stroke is the second leading cause of death and the third leading cause of disability worldwide. Treatment is time limited and delays cost lives. This review discusses modern stroke management, during a time when treatments and guidelines are rapidly evolving. Recent findings Stroke thrombectomy has become the therapy of choice for large vessel occlusion (LVO) strokes. Perfusion imaging techniques, both computed tomography (CT) and MRI, now allow treatment beyond a set time window in specific patients. Both general anaesthesia and conscious sedation are options for patients undergoing stroke thrombectomy. Summary An individualized approach to the patient's anaesthetic management is optimal, and depends on close communication with the neurointerventionalist regarding patient and procedure-specific variables. No specific anaesthetic agent is preferred. Guiding principles are minimization of time delay, and maintenance of cerebral perfusion pressure. Correspondence to David L. McDonagh, MD, 5323 Harry Hines Blvd., Dallas, TX, USA. Tel: +1 214 648 6400; e-mail: David.mcdonagh@utsouthwestern.edu Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.

Neurophysiological monitoring during neurosurgery: anesthetic considerations based on outcome evidence Purpose of review This article reviews the recent outcome studies that investigated intraoperative neurophysiological monitoring (IONM) during spine, neurovascular and brain tumor surgery. Recent findings Several recent studies have focused on identifying which types of neurosurgical procedures might benefit most from IONM use. Despite conflicting literature regarding its efficacy in improving neurological outcomes, many experts have advocated for the use of IONM in neurosurgery. Several themes have emerged from the recent literature: the entire perioperative team must always work together to ensure adequate communication and intervention; systems and checklists, in which each member of the perioperative team has a clearly defined role, can be useful in the event of a sudden intraoperative changes in electrophysiological signals; regardless of the IONM modality used, any sudden change in electrophysiological signal should prompt an immediate and appropriate intervention; a multimodal IONM approach is often, but not always, advantageous over a single IONM approach. Summary For neurosurgical procedures that can be complicated by neural injury, the use of IONM should be considered according to specific patient and surgical factors. Future studies should focus on improving IONM technology and optimizing sensitivity and specificity for detecting any impending neural damage. Correspondence to Shaun E. Gruenbaum, MD, PhD, Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Jacksonville, FL 32224, USA. Tel: +1 904 956 3398; e-mail: gruenbaum.shaun@mayo.edu Copyright © 2019 YEAR Wolters Kluwer Health, Inc. All rights reserved.