Effects of Volatile Anesthetics on Mortality and Postoperative Pulmonary and Other Complications in Patients Undergoing Surgery

Effect of volatile versus propofol anaesthesia on major complications and mortality after cardiac surgery: a multicentre randomised trial

BACKGROUND

The comparative effectiveness of volatile anaesthesia and total intravenous anaesthesia (TIVA) in terms of patient outcomes after cardiac surgery remains a topic of debate.

METHODS

Multicentre randomised trial in 16 tertiary hospitals in China. Adult patients undergoing elective cardiac surgery were randomised in a 1:1 ratio to receive volatile anaesthesia (sevoflurane or desflurane) or propofol-based TIVA. The primary outcome was a composite of predefined major complications during hospitalisation and mortality 30 days after surgery.

RESULTS

Of the 3123 randomised patients, 3083 (98.7%; mean age 55 yr; 1419 [46.0%] women) were included in the modified intention-to-treat analysis. The composite primary outcome was met by a similar number of patients in both groups (volatile group: 517 of 1531 (33.8%) patients vs TIVA group: 515 of 1552 (33.2%) patients; relative risk 1.02 [0.92-1.12]; P=0.76; adjusted odds ratio 1.05 [0.90-1.22]; P=0.57). Secondary outcomes including 6-month and 1-yr mortality, duration of mechanical ventilation, length of ICU and hospital stay, and healthcare costs, were also similar for the two groups.

CONCLUSIONS

Among adults undergoing cardiac surgery, we found no difference in the clinical effectiveness of volatile anaesthesia and propofol-based TIVA.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR-IOR-17013578).

Myocardial protection in cardiac surgery: a comprehensive review of current therapies and future cardioprotective strategies

Cardiac surgery with cardiopulmonary bypass results in global myocardial ischemia-reperfusion injury, leading to significant postoperative morbidity and mortality. Although cardioplegia is the cornerstone of intraoperative cardioprotection, a number of additional strategies have been identified. The concept of preconditioning and postconditioning, despite its limited direct clinical application, provided an essential contribution to the understanding of myocardial injury and organ protection. Therefore, physicians can use different tools to limit perioperative myocardial injury. These include the choice of anesthetic agents, remote ischemic preconditioning, tight glycemic control, optimization of respiratory parameters during the aortic unclamping phase to limit reperfusion injury, appropriate choice of monitoring to optimize hemodynamic parameters and limit perioperative use of catecholamines, and early reintroduction of cardioprotective agents in the postoperative period. Appropriate management before, during, and after cardiopulmonary bypass will help to decrease myocardial damage. This review aimed to highlight the current advancements in cardioprotection and their potential applications during cardiac surgery.

Unveiling the protective role of sevoflurane in video-assisted thoracoscopic surgery associated-acute lung injury: Inhibition of ferroptosis

Acute lung injury (ALI) frequently occurs after video-assisted thoracoscopic surgery (VATS). Ferroptosis is implicated in several lung diseases. Therefore, the disparate effects and underlying mechanisms of the two commonly used anesthetics (sevoflurane (Sev) and propofol) on VATS-induced ALI need to be clarified. In the present study, enrolled patients were randomly allocated to receive Sev (group S) or propofol anesthesia (group P). Intraoperative oxygenation, morphology of the lung tissue, expression of ZO-1, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), superoxide dismutase (SOD), glutathione (GSH), Fe2+, glutathione peroxidase 4 (GPX4), and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in the lung tissue as well as the expression of TNF-α and IL-6 in plasma were measured. Postoperative complications were recorded. Of the 85 initially screened patients scheduled for VATS, 62 were enrolled in either group S (n = 32) or P (n = 30). Compared with propofol, Sev substantially (1) improved intraoperative oxygenation; (2) relieved histopathological lung injury; (3) increased ZO-1 protein expression; (4) decreased the levels of TNF-α and IL-6 in both the lung tissue and plasma; (5) increased the contents of GSH and SOD but decreased Fe2+ concentration; (6) upregulated the protein expression of p-AKT, Nrf2, HO-1, and GPX4. No significant differences in the occurrence of postoperative outcomes were observed between both groups. In summary, Sev treatment, in comparison to propofol anesthesia, may suppress local lung and systemic inflammatory responses by activating the PI3K/Akt/Nrf2/HO-1 pathway and inhibiting ferroptosis. This cascade of effects contributes to the maintenance of pulmonary epithelial barrier permeability, alleviation of pulmonary injury, and enhancement of intraoperative oxygenation in patients undergoing VATS.

Comparison between propofol and total inhalational anaesthesia on cardiovascular outcomes following on-pump cardiac surgery in higher-risk patients: a randomised controlled pilot and feasibility study

OBJECTIVES

Myocardial revascularisation and cardiopulmonary bypass (CPB) can cause ischaemia-reperfusion injury, leading to myocardial and other end-organ damage. Volatile anaesthetics protect the myocardium in experimental studies. However, there is uncertainty about whether this translates into clinical benefits because of the coadministration of propofol and its detrimental effects, restricting myocardial protective processes.

METHODS

In this single-blinded, parallel-group randomised controlled feasibility trial, higher-risk patients undergoing elective coronary artery bypass graft (CABG) surgery with an additive European System for Cardiac Operative Risk Evaluation ≥5 were randomised to receive either propofol or total inhalational anaesthesia as single agents for maintenance of anaesthesia. The primary outcome was the feasibility of recruiting and randomising 50 patients across two cardiac surgical centres, and secondary outcomes included the feasibility of collecting the planned perioperative data, clinically relevant outcomes and assessments of effective patient identification, screening and recruitment.

RESULTS

All 50 patients were recruited within 11 months in two centres, allowing for a 13-month hiatus in recruitment due to the COVID-19 pandemic. Overall, 50/108 (46%) of eligible patients were recruited. One patient withdrew before surgery and one patient did not undergo surgery. All but one completed in-hospital and 30-day follow-up.

CONCLUSIONS

It is feasible to recruit and randomise higher-risk patients undergoing CABG surgery to a study comparing total inhalational and propofol anaesthesia in a timely manner and with high acceptance and completion rates.

TRIAL REGISTRATION NUMBER

NCT04039854.

Postoperative outcomes after total sevoflurane inhalation sedation using a disposable delivery system (Sedaconda-ACD) in cardiac surgery

Introduction

The COVID-19 pandemic prompted our team to develop new solutions for performing cardiac surgery without intravenous anesthetics due to a shortage of these drugs. We utilized an anesthetic conserving device (Sedaconda-ACD) to administer total inhaled anesthesia because specific vaporizers were unavailable for administering inhaled agents during cardiopulmonary bypass (CPB) in our center. We documented our experience and postoperative cardiovascular outcomes. The primary outcome was the peak level of troponin, with secondary outcomes encompassing other cardiovascular complications.

Material and methods

A single-center retrospective study was conducted. We performed a multivariate analysis with a propensity score. This investigation took place at a large university referral center.

Participants

Adult patients (age ≥ 18) who underwent elective cardiac surgery with CPB between June 2020 to March 2021.

Intervention

During the inclusion period, two anesthesia protocols for the maintenance of anesthesia coexisted-total inhaled anesthesia with Sedaconda-ACD and our classic protocol with intravenous drugs during and after CPB.

Primary endpoint

Troponin peak level recorded after surgery (highest level recorded within 48 h following the surgery).

Results

Out of the 654 included patients, 454 were analyzed after matching (intravenous group = 297 and inhaled group = 157). No significant difference was found between the groups in postoperative troponin peak levels (723 ng/l vs. 993 ng/l-p = 0.2). Total inhaled anesthesia was associated with a decreased requirement for inotropic medications (OR = 0.53, 95% CI 0.29-0.99, p = 0.04).

Conclusion

In our cohort, the Sedaconda-ACD device enabled us to achieve anesthesia without intravenous agents, and we did not observe any increase in postoperative complications. Total inhaled anesthesia with sevoflurane was not associated with a lower incidence of myocardial injury assessed by the postoperative troponin peak level. However, in our cohort, the use of inotropic drugs was lower.

Anaesthetic subspecialties and sustainable healthcare: a narrative review

The principles of environmentally sustainable healthcare as applied to anaesthesia and peri-operative care are well documented. Associated recommendations focus on generic principles that can be applied to all areas of practice. These include reducing the use of inhalational anaesthetic agents and carbon dioxide equivalent emissions of modern peri-operative care. However, four areas of practice have specific patient, surgical and anaesthetic factors that present barriers to the implementation of some of these principles, namely: neuroanaesthesia; obstetric; paediatric; and cardiac anaesthesia. This narrative review describes these factors and synthesises the available evidence to highlight areas of sustainable practice clinicians can address today, as well as posing several unanswered questions for the future. In neuroanaesthesia, improvements can be made by undertaking awake surgery, moving towards more reusables and embracing telemedicine in quaternary services. Obstetric anaesthesia continues to present questions regarding how services can move away from nitrous oxide use or limit its release to the environment. The focus for paediatric anaesthesia is addressing the barriers to total intravenous and regional anaesthesia. For cardiac anaesthesia, a significant emphasis is determining how to focus the substantial resources required on those who will benefit from cardiac interventions, rather than universal implementation. Whilst the landscape of evidence-based sustainable practice is evolving, there remains an urgent need for further original evidence in healthcare sustainability targeting these four clinical areas.

Guidelines for inhaled sedation in the ICU

INTRODUCTION AND OBJECTIVES

Sedation is used in intensive care units (ICU) to improve comfort and tolerance during mechanical ventilation, invasive interventions, and nursing care. In recent years, the use of inhalation anaesthetics for this purpose has increased. Our objective was to obtain and summarise the best evidence on inhaled sedation in adult patients in the ICU, and use this to help physicians choose the most appropriate approach in terms of the impact of sedation on clinical outcomes and the risk-benefit of the chosen strategy.

METHODOLOGY

Given the overall lack of literature and scientific evidence on various aspects of inhaled sedation in the ICU, we decided to use a Delphi method to achieve consensus among a group of 17 expert panellists. The processes was conducted over a 12-month period between 2022 and 2023, and followed the recommendations of the CREDES guidelines.

RESULTS

The results of the Delphi survey form the basis of these 39 recommendations - 23 with a strong consensus and 15 with a weak consensus.

CONCLUSION

The use of inhaled sedation in the ICU is a reliable and appropriate option in a wide variety of clinical scenarios. However, there are numerous aspects of the technique that require further study.

Mechanisms of Action of the Detrimental Effects of Propofol on Survival

Due to its favorable pharmacologic features, propofol is the most commonly used hypnotic agent in perioperative and intensive care settings. However, it also has adverse effects like propofol infusion syndrome and an increased risk of infection. Growing evidence suggests that propofol may worsen clinical outcomes by inhibiting the organ-protective properties of other interventions, such as volatile anesthetics or remote ischemic preconditioning. This editorial describes possible mechanisms underlying the detrimental effects of propofol, and provides an overview of the results of clinical trials evaluating the effects of propofol in various settings.

Total intravenous anesthesia decreases hospital stay but not incidence of postoperative pulmonary complications after lung resection surgery: a propensity score matching study

BACKGROUND

There is no consensus regarding the superiority of volatile or total intravenous anesthesia (TIVA) in reducing the incidence of postoperative pulmonary complications (PPCs) after lung resection surgery (LRS). Thus, the aim of this study was to investigate the different anesthetic regimens and the incidence of PPCs in patients who underwent LRS. We hypothesized that TIVA is associated with a lower incidence of PPCs than volatile anesthesia.

METHODS

This was a retrospective cohort study of patients who underwent LRS at Taipei Veterans General Hospital between January 2016 and December 2020. The patients' charts were reviewed and data on patient characteristics, perioperative features, and postoperative outcomes were extracted and analyzed. The patients were categorized into TIVA or volatile anesthesia groups and their clinical data were compared. Propensity score matching was performed to reduce potential selection bias. The primary outcome was the incidence of PPCs, whereas the secondary outcomes were the incidences of other postoperative events, such as length of hospital stay (LOS) and postoperative nausea and vomiting (PONV).

RESULTS

A total of 392 patients each were included in the TIVA and volatile anesthesia groups. There was no statistically significant difference in the incidence of PPCs between the volatile anesthesia and TIVA groups. The TIVA group had a shorter LOS (p < 0.001) and a lower incidence of PONV than the volatile anesthesia group (4.6% in the TIVA group vs. 8.2% in the volatile anesthesia group; p = 0.041). However, there were no significant differences in reintubation, 30-day readmission, and re-operation rates between the two groups.

CONCLUSIONS

There was no significant difference between the incidence of PPCs in patients who underwent LRS under TIVA and that in patients who underwent LRS under volatile anesthesia. However, TIVA had shorter LOS and lower incidence of PONV which may be a better choice for maintenance of anesthesia in patients undergoing LRS.

Myocardial Protection by Desflurane: From Basic Mechanisms to Clinical Applications

ABSTRACT

Coronary heart disease is an affliction that is common and has an adverse effect on patients' quality of life and survival while also raising the risk of intraoperative anesthesia. Mitochondria are the organelles most closely associated with the pathogenesis, development, and prognosis of coronary heart disease. Ion abnormalities, an acidic environment, the production of reactive oxygen species, and other changes during abnormal myocardial metabolism cause the opening of mitochondrial permeability transition pores, which disrupts electron transport, impairs mitochondrial function, and even causes cell death. Differences in reliability and cost-effectiveness between desflurane and other volatile anesthetics are minor, but desflurane has shown better myocardial protective benefits in the surgical management of patients with coronary artery disease. The results of myocardial protection by desflurane are briefly summarized in this review, and biological functions of the mitochondrial permeability transition pore, mitochondrial electron transport chain, reactive oxygen species, adenosine triphosphate-dependent potassium channels, G protein-coupled receptors, and protein kinase C are discussed in relation to the protective mechanism of desflurane. This article also discusses the effects of desflurane on patient hemodynamics, myocardial function, and postoperative parameters during coronary artery bypass grafting. Although there are limited and insufficient clinical investigations, they do highlight the possible advantages of desflurane and offer additional suggestions for patients.

Intraoperative Factors Modifying the Risk of Postoperative Pulmonary Complications After Living Donor Liver Transplantation

BACKGROUND

The relationship between intraoperative anesthetic management and postoperative pulmonary complications (PPCs) after liver transplantation is not fully understood. We aimed to determine the intraoperative contributors to PPC.

METHODS

The retrospectively collected cohort included 605 patients who underwent living donor liver transplantation. PPCs comprised respiratory failure, respiratory infection, pulmonary edema, atelectasis (at least moderate degree), pneumothorax, and pleural effusion (at least moderate degree). The presence and type of PPC were evaluated by 2 pulmonary physicians. Logistic regression analysis was performed to determine the association between perioperative variables and PPC risk.

RESULTS

Of the 605 patients, 318 patients (52.6%) developed 486 PPCs. Multivariable analysis demonstrated that PPC risk decreased with low tidal volume ventilation (odds ratio [OR] 0.62 [0.41-0.94], P  = 0.023) and increased with greater driving pressure at the end of surgery (OR 1.08 [1.01-1.14], P  = 0.018), prolonged hypotension (OR 1.85 [1.27-2.70], P  = 0.001), and blood albumin level ≤3.0 g/dL at the end of surgery (OR 2.43 [1.51-3.92], P  < 0.001). Survival probability at 3, 6, and 12 mo after transplantation was 91.2%, 89.6%, and 86.5%, respectively, in patients with PPCs and 98.3%, 96.5%, and 93.4%, respectively, in patients without PPCs (hazard ratio 2.2 [1.3-3.6], P  = 0.004). Graft survival probability at 3, 6, and 12 mo after transplantation was 89.3%, 87.1%, and 84.3%, respectively, in patients with PPCs and 97.6%, 95.8%, and 92.7%, respectively, in patients without PPCs (hazard ratio 2.3 [1.4-3.7], P  = 0.001).

CONCLUSIONS

We found that tidal volume, driving pressure, hypotension, and albumin level during living donor liver transplantation were significantly associated with PPC risk. These data may help determine patients at risk of PPC or develop an intraoperative lung-protective strategy for liver transplant recipients.

Guidelines on perioperative optimization protocol for the adult patient 2023

OBJECTIVE

The French Society of Anesthesiology and Intensive Care Medicine [Société Française d'Anesthésie et de Réanimation (SFAR)] aimed at providing guidelines for the implementation of perioperative optimization programs.

DESIGN

A consensus committee of 29 experts from the SFAR was convened. A formal conflict-of-interest policy was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence.

METHODS

Four fields were defined: 1) Generalities on perioperative optimization programs; 2) Preoperative measures; 3) Intraoperative measures and; 4) Postoperative measures. For each field, the objective of the recommendations was to answer a number of questions formulated according to the PICO model (population, intervention, comparison, and outcomes). Based on these questions, an extensive bibliographic search was carried out using predefined keywords according to PRISMA guidelines and analyzed using the GRADE® methodology. The recommendations were formulated according to the GRADE® methodology and then voted on by all the experts according to the GRADE grid method. As the GRADE® methodology could have been fully applied for the vast majority of questions, the recommendations were formulated using a "formalized expert recommendations" format.

RESULTS

The experts' work on synthesis and application of the GRADE® method resulted in 30 recommendations. Among the formalized recommendations, 19 were found to have a high level of evidence (GRADE 1±) and ten a low level of evidence (GRADE 2±). For one recommendation, the GRADE methodology could not be fully applied, resulting in an expert opinion. Two questions did not find any response in the literature. After two rounds of rating and several amendments, strong agreement was reached for all the recommendations.

CONCLUSIONS

Strong agreement among the experts was obtained to provide 30 recommendations for the elaboration and/or implementation of perioperative optimization programs in the highest number of surgical fields.

Pharmacological Cardioprotection against Ischemia Reperfusion Injury-The Search for a Clinical Effective Therapy

Pharmacological conditioning aims to protect the heart from myocardial ischemia-reperfusion injury (IRI). Despite extensive research in this area, today, a significant gap remains between experimental findings and clinical practice. This review provides an update on recent developments in pharmacological conditioning in the experimental setting and summarizes the clinical evidence of these cardioprotective strategies in the perioperative setting. We start describing the crucial cellular processes during ischemia and reperfusion that drive acute IRI through changes in critical compounds (∆G_ATP, Na⁺, Ca²⁺, pH, glycogen, succinate, glucose-6-phosphate, mitoHKII, acylcarnitines, BH₄, and NAD⁺). These compounds all precipitate common end-effector mechanisms of IRI, such as reactive oxygen species (ROS) generation, Ca²⁺ overload, and mitochondrial permeability transition pore opening (mPTP). We further discuss novel promising interventions targeting these processes, with emphasis on cardiomyocytes and the endothelium. The limited translatability from basic research to clinical practice is likely due to the lack of comorbidities, comedications, and peri-operative treatments in preclinical animal models, employing only monotherapy/monointervention, and the use of no-flow (always in preclinical models) versus low-flow ischemia (often in humans). Future research should focus on improved matching between preclinical models and clinical reality, and on aligning multitarget therapy with optimized dosing and timing towards the human condition.

Propofol and survival: an updated meta-analysis of randomized clinical trials

BACKGROUND

Propofol is one of the most widely used hypnotic agents in the world. Nonetheless, propofol might have detrimental effects on clinically relevant outcomes, possibly due to inhibition of other interventions' organ protective properties. We performed a systematic review and meta-analysis of randomized controlled trials to evaluate if propofol reduced survival compared to any other hypnotic agent in any clinical setting.

METHODS

We searched eligible studies in PubMed, Google Scholar, and the Cochrane Register of Clinical Trials. The following inclusion criteria were used: random treatment allocation and comparison between propofol and any comparator in any clinical setting. The primary outcome was mortality at the longest follow-up available. We conducted a fixed-effects meta-analysis for the risk ratio (RR). Using this RR and 95% confidence interval, we estimated the probability of any harm (RR > 1) through Bayesian statistics. We registered this systematic review and meta-analysis in PROSPERO International Prospective Register of Systematic Reviews (CRD42022323143).

RESULTS

We identified 252 randomized trials comprising 30,757 patients. Mortality was higher in the propofol group than in the comparator group (760/14,754 [5.2%] vs. 682/16,003 [4.3%]; RR = 1.10; 95% confidence interval, 1.01-1.20; p = 0.03; I² = 0%; number needed to harm = 235), corresponding to a 98.4% probability of any increase in mortality. A statistically significant mortality increase in the propofol group was confirmed in subgroups of cardiac surgery, adult patients, volatile agent as comparator, large studies, and studies with low mortality in the comparator arm.

CONCLUSIONS

Propofol may reduce survival in perioperative and critically ill patients. This needs careful assessment of the risk versus benefit of propofol compared to other agents while planning for large, pragmatic multicentric randomized controlled trials to provide a definitive answer.

Cognitive function and delirium following sevoflurane or propofol anesthesia for valve replacement surgery: A multicenter randomized controlled trial

Cognitive dysfunction is a common postoperative neurological complication in patients undergoing valve replacement surgery. This study aimed to compare the effects of sevoflurane versus propofol-based total intravenous anesthesia on the incidence of cognitive dysfunction following valve replacement surgery. This multicenter, randomized, controlled double-blinded study was conducted in three teaching hospitals in China. Patients receiving on-pump valve replacement surgery were enrolled. Stratified block randomization was used to randomly assign patients 1:1 to receive sevoflurane (1.0-1.5 MAC) or propofol (2.0-3.0 mg/kg/h) for anesthesia maintenance. The primary outcome was the incidence of cognitive dysfunction assessed by four cognitive tests before, as well as 7-14 days after surgery. Patients were randomly assigned to receive sevoflurane anesthesia (n = 144) or propofol-based total intravenous anesthesia (n = 145). The incidence of postoperative cognitive dysfunction in the sevoflurane anesthesia group (31.9%) was significantly lower than that in the total intravenous anesthesia group (43.4%; relative risk 0.61, 95% confidence interval [CI]: 0.38-0.97, p = 0.044). There was no difference in the incidence of delirium between patients receiving sevoflurane and total intravenous anesthesia (27.8% [35/144] vs. 25.9% [35/145], 1.10, 95% CI: 0.64 to 1.90, p = 0.736). There was a significant difference in the Katz Index on day 3 after surgery (3 [0.9) vs. 3 (1.0], 0.095, 95% CI: 0.05 to 0.43, p = 0.012). No difference was observed in other outcomes between the two groups. For patients undergoing on-pump valve replacement surgery, sevoflurane anesthesia had a smaller effect on cognitive function and independence in daily life activities compared with propofol anesthesia.

Volatile Versus Total Intravenous Anesthesia on Postoperative Delirium in Adult Patients Undergoing Cardiac Valve Surgery: A Randomized Clinical Trial

BACKGROUND

The effect of anesthesia regimens on postoperative delirium after on-pump cardiac valve surgery is yet undetermined. This study aimed to evaluate the effect of volatile anesthesia compared with propofol-based total intravenous anesthesia (TIVA) on the occurrence of delirium after on-pump cardiac valve surgery.

METHODS

This randomized clinical trial was conducted at a university academic hospital in China, from February 2019 to January 2021. Patients scheduled for on-pump cardiac valve surgery or combined valve with coronary artery bypass grafting (CABG) surgeries were randomly assigned to receive anesthesia maintenance with either a volatile anesthetic (sevoflurane or desflurane) or propofol-based TIVA. The primary outcome was the incidence of delirium during the first 7 days after surgery, assessed using the confusion assessment method for the intensive care unit (ICU). The secondary outcomes included duration of delirium, subtypes of delirium, 30-day mortality, pain score, major morbidity (including cerebral infarction, respiratory failure, and pneumonia), duration of mechanical ventilation, and lengths of ICU and hospital stay. The statistical analysis of the primary outcome variable was by Pearson's χ 2 test.

RESULTS

Among the 684 patients analyzed (mean age, 53.8 years; 381 [55.7%] women), 676 were assessed for the primary outcome. Postoperative delirium occurred in 63 of 337 (18.7%) patients receiving volatile anesthesia versus 76 of 339 (22.4%) patients receiving propofol-based TIVA (relative risk, 0.80; 95% confidence interval [CI], 0.55-1.16; P = .231). There were no significant differences between the groups in any of the secondary outcomes.

CONCLUSIONS

Among patients undergoing on-pump cardiac valve surgery, anesthesia maintenance with a volatile agent did not result in significantly fewer occurrences of postoperative delirium than propofol-based TIVA.

Anesthetic Preferences for Cardiac Anesthesia: A Survey of the Society of Cardiovascular Anesthesiologists

BACKGROUND

Volatile anesthetics have been historically preferred for cardiac anesthesia, but the evidence for their superiority to intravenous agents is mixed. We conducted a survey to better understand the current state of practice and the rationale behind provider preferences for anesthesia for cardiac surgery with cardiopulmonary bypass. We hypothesized that anesthetic preference would vary considerably among surveyed providers without a clear majority, as would the rationale behind those preferences.

METHODS

Email invitations were sent to members of the Society of Cardiovascular Anesthesiologists, who were asked to identify the anesthetics or sedatives they typically prefer to administer during induction, prebypass, bypass, postbypass, and postoperative periods and why they prefer those agents. Members' beliefs regarding the importance of anesthetics on postoperative outcomes were also assessed.

RESULTS

Invitations were sent on 2 separate dates to 3328 and 3274 members, of whom 689 (21%) responded. The median (interquartile range [IQR]) respondent age was 45 (37-56) years, 79% were men, and 75% were fellowship trained. The most frequently chosen drug for induction was propofol (80%). Isoflurane was the most frequently selected primary agent for the prebypass (57%), bypass (62%), and postbypass periods (50%). Sevoflurane was the second most frequently selected (30%; 17%, and 24%, respectively). Propofol was the third most frequently selected agent for the bypass (14%) and postbypass periods (17%). Ease of use was the most frequently selected reason for administering isoflurane and sevoflurane for each period. During bypass, the second most frequently selected rationale for using isoflurane and sevoflurane was institutional practice. A total of 76% responded that the perfusionist typically delivers the bypass anesthetic. Ischemic preconditioning, organ protection, and postoperative cognitive function were infrequently selected as rationales for preferring the volatile anesthetics. Most respondents (73%) think that anesthetics have organ-protective properties, especially isoflurane (74%) and sevoflurane (59%), and 72% believed that anesthetic choice contributes to patient outcome. The median (IQR) agreement (0 = strongly disagree to 100 = strongly agree) was 72 (63-85) for the statement that "inhaled anesthetics are an optimal maintenance anesthetic for cardiac surgery."

CONCLUSIONS

In a survey of cardiac anesthesiologists, a majority of respondents indicated that they prefer volatile anesthetics for maintenance of anesthesia, that anesthetic selection impacts patient outcomes, and that volatile anesthetics have organ-protective properties. The members' rationales for preferring these agents possibly reflect that practical considerations, such as ease of use, effectiveness, and institutional practice, also influence anesthetic selection during cardiac surgery in addition to considerations such as organ protection.

Isoflurane Preconditioning May Attenuate Cardiomyocyte Injury Induced by Hypoxia/Reoxygenation Possibly by Regulating miR-363-3p

This study attempted to explore whether miR-363-3p play a role in the isoflurane (ISO)-mediated protective effect of cardiomyocyte injury induced by hypoxia/reoxygenation (H/R). A myocardial cell injury model was established, and the different preconditioning ISO concentrations were screened and determined. The miR-363-3p level was detected by RT-qPCR. The effects of miR-363-3p on proliferation and apoptosis of H9c2 cells were detected by CCK-8 assay and flow cytometry. Myocardial injury indexes were determined by enzyme-linked immunosorbent assay (ELISA). The interaction of miR-363-3p with the 3'-UTR of the KLF2 gene was confirmed by luciferase reporter gene assay. ISO pretreatment can reduce the up-regulation of miR-363-3p after H/R injury. ISO pretreatment reduces the inhibition of cell viability and the promotion of cell apoptosis induced by H/R stimuli, while the overexpression of miR-363-3p counteracts the protective effect of ISO pretreatment. Meanwhile, ISO pretreatment also reduced the level of markers of H/R-induced myocardial injury. Moreover, luciferase reporter analysis showed that KLF2 was the downstream target gene of miR-363-3p. ISO pretreatment may alleviate H/R-induced cardiomyocyte injury by regulating miR-363-3p.

Effects of propofol and inhaled anesthetics on postoperative complications for the patients undergoing one lung ventilation: A meta-analysis

INTRODUCTION

With the widespread use of one-lung ventilation (OLV) in thoracic surgery, it is unclear whether maintenance anesthetics such as propofol and inhaled anesthetics are associated with postoperative complications. The purpose of this study was to compare the effects of propofol and inhaled anesthetics on postoperative complications in OLV patients.

METHODS

PubMed, EMBASE, Medline, and Cochrane Library were searched for relevant randomized controlled trials until 09/2021. All randomized controlled trials comparing the effect of propofol versus inhaled anesthetics on postoperative complications in OLV patients were included. All randomized controlled trials comparing:(a) major complications (b) postoperative pulmonary complications (c) postoperative cognitive function (MMSE score) (d) length of hospital stay (e) 30-day mortality, were included.

RESULTS

Thirteen randomized controlled trials involving 2522 patients were included in the analysis. Overall, there was no significant difference in major postoperative complications between the inhaled anesthetic and propofol groups (OR 0.78, 95%CI 0.54 to 1.13, p = 0.19; I2 = 0%). However, more PPCs were detected in the propofol group compared to the inhalation anesthesia group (OR 0.62, 95%CI 0.44 to 0.87, p = 0.005; I2 = 37%). Both postoperative MMSE score (SMD -1.94, 95%CI -4.87 to 0.99, p = 0.19; I2 = 100%) and hospital stay (SMD 0.05, 95%CI -0.29 to 0.39, p = 0.76; I2 = 73%) were similar between the two groups. The 30-day mortality rate was also not significantly different between groups (OR 0.79, 95%CI 0.03 to 18, p = 0.88; I2 = 63%).

CONCLUSIONS

In patients undergoing OLV, general anesthesia with inhaled anesthetics reduced PPC compared to propofol, but did not provide clear benefits on other major complications, cognitive function, length of hospital stay, or mortality.

Volatile Anaesthesia versus Total Intravenous Anaesthesia for Cardiac Surgery—A Narrative Review

Recent research has contested the previously accepted paradigm that volatile anaesthetics improve outcomes in cardiac surgery patients when compared to intravenous anaesthesia. In this review we summarise the mechanisms of myocardial ischaemia/reperfusion injury and cardioprotection in cardiac surgery. In addition, we make a comprehensive analysis of evidence comparing outcomes in patients undergoing cardiac surgery under volatile or intravenous anaesthesia, in terms of mortality and morbidity (cardiac, neurological, renal, pulmonary).

Inhaled sedation in the intensive care unit

Inhaled sedation with halogenated agents, such as isoflurane or sevoflurane, is now feasible in intensive care unit (ICU) patients through dedicated vaporisers and scavenging systems. Such a sedation strategy requires specific equipment and adequate training of ICU teams. Isoflurane and sevoflurane have ideal pharmacological properties that allow efficient, well-tolerated, and titratable light-to-deep sedation. In addition to their function as sedative agents, these molecules may have clinical benefits that could be especially relevant to ICU patients. Our goal was to summarise the pharmacological basis and practical aspects of inhaled ICU sedation, review the available evidence supporting inhaled sedation as a viable alternative to intravenous sedation, and discuss the remaining areas of uncertainty and future perspectives of development.

Guidelines on enhanced recovery after cardiac surgery under cardiopulmonary bypass or off-pump

OBJECTIVE

To provide recommendations for enhanced recovery after cardiac surgery (ERACS) based on a multimodal perioperative medicine approach in adult cardiac surgery patients with the aim of improving patient satisfaction, reducing postoperative mortality and morbidity, and reducing the length of hospital stay.

DESIGN

A consensus committee of 20 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Society of Thoracic and Cardiovascular Surgery (Société française de chirurgie thoracique et cardio-vasculaire, SFCTCV) was convened. A formal conflict-of-interest policy was developed at the onset of the process and enforced throughout. The entire guideline process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide the assessment of the quality of evidence.

METHODS

Six fields were defined: (1) selection of the patient pathway and its information; (2) preoperative management and rehabilitation; (3) anaesthesia and analgesia for cardiac surgery; (4) surgical strategy for cardiac surgery and bypass management; (5) patient blood management; and (6) postoperative enhanced recovery. For each field, the objective of the recommendations was to answer questions formulated according to the PICO model (Population, Intervention, Comparison, Outcome). Based on these questions, an extensive bibliographic search was carried out and analyses were performed using the GRADE approach. The recommendations were formulated according to the GRADE methodology and then voted on by all the experts according to the GRADE grid method.

RESULTS

The SFAR/SFCTCV guideline panel provided 33 recommendations on the management of patients undergoing cardiac surgery under cardiopulmonary bypass or off-pump. After three rounds of voting and several amendments, a strong agreement was reached for the 33 recommendations. Of these recommendations, 10 have a high level of evidence (7 GRADE 1+ and 3 GRADE 1-); 19 have a moderate level of evidence (15 GRADE 2+ and 4 GRADE 2-); and 4 are expert opinions. Finally, no recommendations were provided for 3 questions.

CONCLUSIONS

Strong agreement existed among the experts to provide recommendations to optimise the complete perioperative management of patients undergoing cardiac surgery.

Potential Markers of Neurocognitive Disorders After Cardiac Surgery: A Bibliometric and Visual Analysis

Background

Identifying useful markers is essential for diagnosis and prevention of perioperative neurocognitive disorders (PNDs). Here, we attempt to understand the research basis and status, potential hotspots and trends of predictive markers associated with PNDs after cardiac surgery via bibliometric analysis.

Methods

A total of 4,609 original research articles and reviews that cited 290 articles between 2001 and 2021 were obtained from the Web of Science Core Collection (WoSCC) as the data source. We used the software CiteSpace to generate and analyze visual networks of bibliographic information, including published years and journals, collaborating institutions, co-cited references, and co-occurring keywords.

Results

The number of annual and cumulative publications from 2001 to 2021 has been increasing on the whole. The Harvard Medical School was a very prolific and important institution in this field. The journal of Ann Thorac Surg (IF 4.33) had the most publications, while New Engl J Med was the most cited journal. Neuron-specific enolase (NSE), S100b and kynurenic acid (KYNA) were frequently discussed as possible markers of PNDs in many references. Cardiopulmonary bypass (CPB) was a keyword with high frequency (430) and sigma (6.26), and inflammation was the most recent burst keyword.

Conclusion

Potential markers of PNDs has received growing attention across various disciplines for many years. The research basis mainly focuses on three classic biomarkers of S100b, NSE, and KYNA. The most active frontiers are the inflammation-related biomarkers (e.g., inflammatory cells, cytokines, or mediators) and surgery-related monitoring parameters (e.g., perfusion, oxygen saturation, and the depth of anesthesia).

The Protective Effect of Sevoflurane Conditionings Against Myocardial Ischemia/Reperfusion Injury: A Systematic Review and Meta-Analysis of Preclinical Trials in in-vivo Models

Objective

Myocardial ischemia/reperfusion injury (IRI) is a common and serious complication in clinical practice. Sevoflurane conditionings have been identified to provide a protection against myocardial IRI in animal experiments, but their true clinical benefits remain controversial. Here, we aimed to analyze the preclinical evidences obtained in animal models of myocardial IRI and explore the possible reasons for controversial clinical benefits.

Methods

Our primary outcome was the difference in mean infarct size between the sevoflurane and control groups in animal models of myocardial IRI. After searching the databases of PubMed, Embase, Web of Science, and the Cochrane Library, a systematic review retrieved 37 eligible studies, from which 28 studies controlled comparisons of sevoflurane preconditioning (SPreC) and 40 studies controlled comparisons of sevoflurane postconditioning (SPostC) that were made in a pooled random-effects meta-analysis. In total, this analysis included data from 313 control animals and 536 animals subject to sevoflurane conditionings.

Results

Pooled estimates for primary outcome demonstrated that sevoflurane could significantly reduce the infarct size after myocardial IRI whether preconditioning [weighted mean difference (WMD): −18.56, 95% CI: −23.27 to −13.85, P < 0.01; I² = 94.1%, P < 0.01] or postconditioning (WMD: −18.35, 95% CI: −20.88 to −15.83, P < 0.01; I² = 90.5%, P < 0.01) was performed. Interestingly, there was significant heterogeneity in effect size that could not be explained by any of the prespecified variables by meta-regression and stratified analysis. However, sensitivity analysis still identified the cardioprotective benefits of sevoflurane conditionings with robust results.

Conclusion

Sevoflurane conditionings can significantly reduce infarct size in in-vivo models of myocardial IRI. Given the fact that there is a lack of consistency in the quality and design of included studies, more well-performed in-vivo studies with the detailed characterization of sevoflurane protocols, especially studies in larger animals regarding cardioprotection effects of sevoflurane, are still required.

Inhalation anaesthesia compared with total intravenous anaesthesia and postoperative complications in colorectal cancer surgery: an observational registry-based study†

BACKGROUND

Postoperative complications are common after colorectal surgery, and possibly related to the type of anaesthesia. We aimed to determine associations between the type of anaesthesia and complications after colorectal cancer surgery using Danish registries.

METHODS

Patients undergoing colorectal cancer surgery (2004-18) were identified in the Danish Colorectal Cancer Group Database. The cohort was enriched with the Danish Anaesthesia Database and Danish National Prescription Registry data linked by Danish Central Person Registration number. Patients were classified according to type of general anaesthesia: inhalation or TIVA. Confounders were adjusted by propensity score matching. The primary outcome was complications within 30 days postoperatively. Secondarily, we assessed specific medical and surgical complications.

RESULTS

We identified 22 179 individuals undergoing colorectal cancer surgery with accompanying anaesthesia data. Propensity score matching yielded 8722 individuals per group. After propensity score matching, postoperative complications were seen in 1933 (22.2%) patients undergoing inhalation anaesthesia and in 2199 (25.2%) undergoing TIVA (odds ratio [OR]=0.84; 95% confidence interval [CI], 0.79-0.91). Although no difference was observed for medical complications, 1369 (15.7%) undergoing inhalation anaesthesia had surgical complications compared with 1708 (19.6%) undergoing TIVA (OR=0.76; 95% CI, 0.71-0.83). Rates of wound dehiscence, anastomotic leak, ileus, wound abscess, intra-abdominal abscess, and sepsis were statistically significantly lower in the inhalation anaesthesia group.

CONCLUSION

In this propensity score-matched registry study, use of inhalation anaesthesia was associated with fewer postoperative complications after colorectal cancer surgery than use of TIVA. Inhalation anaesthesia was associated with fewer complications related to wound healing and surgical infections.

Effects of Inhalation versus Total Intravenous Anesthesia on Postoperative Pulmonary Complications after Anatomic Pulmonary Resection

Background

No consensus exists regarding whether volatile anesthetics are superior to intravenous anesthetics for reducing postoperative pulmonary complications (PPCs) in patients undergoing general anesthesia for surgery. Studies of this issue focused on anatomic pulmonary resection are lacking. This study compared the effects of total intravenous anesthesia (TIVA) versus volatile anesthesia on PPCs after anatomic pulmonary resection in patients with lung cancer.

Methods

This retrospective study examined the medical records of patients with lung cancer who underwent lung resection at our center between January 2018 and October 2020. The primary outcome was the incidence of PPCs, which included prolonged air leak, pneumonia, acute respiratory distress syndrome, empyema, atelectasis requiring bronchofiberscopy (BFS), acute lung injury (ALI), bronchopleural fistula (BPF), pulmonary embolism, and pulmonary edema. Propensity score matching (PSM) was used to balance the 2 groups. In total, 579 anatomic pulmonary resection cases were included in the final analysis.

Results

The analysis showed no statistically significant difference between the volatile anesthesia and TIVA groups in terms of PPCs, except for prolonged air leak. Neither of the groups showed atelectasis requiring BFS, ALI, BPF, pulmonary embolism, or pulmonary edema after PSM. However, the length of hospitalization, intensive care unit stay, and duration of chest tube indwelling were shorter in the TIVA group.

Conclusion

Volatile anesthetics showed no superiority compared to TIVA in terms of PPCs after anatomical pulmonary resection in patients with lung cancer. Considering the advantages of each anesthetic modality, appropriate anesthetic modalities should be used in patients with different risk factors and situations.

Inhalational or total intravenous anesthetic for cardiac surgery: does the debate even exist?

PURPOSE OF REVIEW

Perioperative myocardial injury related to cardiac surgery is associated with organ dysfunction and increased mortality. Volatile anesthetics (VA) have been used during cardiac surgery for decades because of their direct and indirect preconditioning and protection against ischemia-reperfusion injury. The current review provides a summary of the latest literature comparing pharmacological preconditioning and the potential benefits of using VA versus total intravenous anesthesia (TIVA) for general anesthesia to improve outcomes after cardiac surgery.

RECENT FINDINGS

Recent literature reports lower mortality and better outcomes when VA is used alone or in combination with remote ischemic preconditioning compared with groups receiving TIVA. However, inconsistent research findings over the years have led to continued debate regarding the anesthetic technique considered more favorable for cardiac surgery.

SUMMARY

Research findings regarding the use of volatile anesthetic versus TIVA for better outcomes after cardiac surgery are inconsistent. Variability in timing, duration, dosing, and type of VA as well as surgical and patient-related factors may have influenced these results. Therefore, either technique can reasonably be adopted depending on provider and institutional preference and used safely in patients undergoing cardiac surgery.

Heart Failure after Cardiac Surgery: The Role of Halogenated Agents, Myocardial Conditioning and Oxidative Stress

Heart disease requires a surgical approach sometimes. Cardiac-surgery patients develop heart failure associated with ischemia induced during extracorporeal circulation. This complication could be decreased with anesthetic drugs. The cardioprotective effects of halogenated agents are based on pre- and postconditioning (sevoflurane, desflurane, or isoflurane) compared to intravenous hypnotics (propofol). We tried to put light on the shadows walking through the line of the halogenated anesthetic drugs’ effects in several enzymatic routes and oxidative stress, waiting for the final results of the ACDHUVV-16 clinical trial regarding the genetic modulation of this kind of drugs.

Longitudinal Impact of WTC Dust Inhalation on Rat Cardiac Tissue Transcriptomic Profiles

First responders (FR) exposed to the World Trade Center (WTC) Ground Zero air over the first week after the 9/11 disaster have an increased heart disease incidence compared to unexposed FR and the general population. To test if WTC dusts were causative agents, rats were exposed to WTC dusts (under isoflurane [ISO] anesthesia) 2 h/day on 2 consecutive days; controls received air/ISO or air only. Hearts were collected 1, 30, 240, and 360 d post-exposure, left ventricle total RNA was extracted, and transcription profiles were obtained. The data showed that differentially expressed genes (DEG) for WTC vs. ISO rats did not reach any significance with a false discovery rate (FDR) < 0.05 at days 1, 30, and 240, indicating that the dusts did not impart effects beyond any from ISO. However, at day 360, 14 DEG with a low FDR were identified, reflecting potential long-term effects from WTC dust alone, and the majority of these DEG have been implicated as having an impact on heart functions. Furthermore, the functional gene set enrichment analysis (GSEA) data at day 360 showed that WTC dust could potentially impact the myocardial energy metabolism via PPAR signaling and heart valve development. This is the first study showing that WTC dust could significantly affect some genes that are associated with the heart/CV system, in the long term. Even > 20 years after the 9/11 disaster, this has potentially important implications for those FR exposed repeatedly at Ground Zero over the first week after the buildings collapsed.

Comparison of direct costs associated with the use of balanced general anesthesia and total intravenous anesthesia (TIVA) techniques

Introduction: Healthcare costs are increasing against the backdrop of scarce resources. Surgical procedures are an important part of healthcare spending, and the cost of anesthetic techniques is relevant as part of the total cost of care and it is a potential target for expenditure optimization. Although important economic differences have been reported internationally for general anesthesia options, there are no publications in Colombia that compare current costs and allow for informed and financially responsible decision-making. Objective: To quantify and compare direct costs associated with the various general anesthesia options most frequently used at the present time. Methods: Cost minimization analysis based on a theoretical model of balanced general anesthesia using isoflurane, sevoflurane, desflurane in combination with remifentanil, and TIVA (propofol and remifentanil). Initial results were obtained using a deterministic simulation method and a sensitivity analysis was performed using a Monte Carlo simulation. Results: The average total cost per case for the different anesthetic techniques was COP 126381 for sevoflurane, COP 97706 for isoflurane, COP 288605 for desflurane and COP 222 960 for TIVA. Conclusions: Balanced general anesthesia with desflurane is the most costly alternative, 1.2 times more expensive than TIVA, and 2 and 3 times more costly than balanced anesthesia with sevoflurane and isoflurane, respectively. TIVA ranks second with a cost 1.8 times higher than balanced anesthesia with sevoflurane and 2.5 times higher than balanced anesthesia with isoflurane.

Effect of Volatile Anesthetics on Myocardial Infarction After Coronary Artery Surgery: A Post Hoc Analysis of a Randomized Trial

OBJECTIVE

To investigate the effect of volatile anesthetics on the rates of postoperative myocardial infarction (MI) and cardiac death after coronary artery bypass graft (CABG).

DESIGN

A post hoc analysis of a randomized trial.

SETTING

Cardiac surgical operating rooms.

PARTICIPANTS

Patients undergoing elective, isolated CABG.

INTERVENTIONS

Patients were randomized to receive a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or total intravenous anesthesia (TIVA). The primary outcome was hemodynamically relevant MI (MI requiring high-dose inotropic support or prolonged intensive care unit stay) occurring within 48 hours from surgery. The secondary outcome was 1-year death due to cardiac causes.

MEASUREMENTS AND MAIN RESULTS

A total of 5,400 patients were enrolled between April 2014 and September 2017 (2,709 patients randomized to the volatile anesthetics group and 2,691 to TIVA). The mean age was 62 ± 8.4 years, and the median baseline ejection fraction was 57% (50-67), without differences between the 2 groups. Patients in the volatile group had a lower incidence of MI with hemodynamic complications both in the per-protocol (14 of 2,530 [0.6%] v 27 of 2,501 [1.1%] in the TIVA group; p = 0.038) and as-treated analyses (16 of 2,708 [0.6%] v 29 of 2,617 [1.1%] in the TIVA group; p = 0.039), but not in the intention-to-treat analysis (17 of 2,663 [0.6%] v 28 of 2,667 [1.0%] in the TIVA group; p = 0.10). Overall, deaths due to cardiac causes were lower in the volatile group (23 of 2,685 [0.9%] v 40 of 2,668 [1.5%] than in the TIVA group; p = 0.03).

CONCLUSIONS

An anesthetic regimen, including volatile agents, may be associated with a lower rate of postoperative MI with hemodynamic complication in patients undergoing CABG. Furthermore, it may reduce long-term cardiac mortality.

Perioperative Pulmonary Atelectasis: Part II. Clinical Implications

The development of pulmonary atelectasis is common in the surgical patient. Pulmonary atelectasis can cause various degrees of gas exchange and respiratory mechanics impairment during and after surgery. In its most serious presentations, lung collapse could contribute to postoperative respiratory insufficiency, pneumonia, and worse overall clinical outcomes. A specific risk assessment is critical to allow clinicians to optimally choose the anesthetic technique, prepare appropriate monitoring, adapt the perioperative plan, and ensure the patient's safety. Bedside diagnosis and management have benefited from recent imaging advancements such as lung ultrasound and electrical impedance tomography, and monitoring such as esophageal manometry. Therapeutic management includes a broad range of interventions aimed at promoting lung recruitment. During general anesthesia, these strategies have consistently demonstrated their effectiveness in improving intraoperative oxygenation and respiratory compliance. Yet these same intraoperative strategies may fail to affect additional postoperative pulmonary outcomes. Specific attention to the postoperative period may be key for such outcome impact of lung expansion. Interventions such as noninvasive positive pressure ventilatory support may be beneficial in specific patients at high risk for pulmonary atelectasis (e.g., obese) or those with clinical presentations consistent with lung collapse (e.g., postoperative hypoxemia after abdominal and cardiothoracic surgeries). Preoperative interventions may open new opportunities to minimize perioperative lung collapse and prevent pulmonary complications. Knowledge of pathophysiologic mechanisms of atelectasis and their consequences in the healthy and diseased lung should provide the basis for current practice and help to stratify and match the intensity of selected interventions to clinical conditions.

Renal and Cerebral Hypoxia and Inflammation During Cardiopulmonary Bypass

Cardiac surgery-associated acute kidney injury and brain injury remain common despite ongoing efforts to improve both the equipment and procedures deployed during cardiopulmonary bypass (CPB). The pathophysiology of injury of the kidney and brain during CPB is not completely understood. Nevertheless, renal (particularly in the medulla) and cerebral hypoxia and inflammation likely play critical roles. Multiple practical factors, including depth and mode of anesthesia, hemodilution, pump flow, and arterial pressure can influence oxygenation of the brain and kidney during CPB. Critically, these factors may have differential effects on these two vital organs. Systemic inflammatory pathways are activated during CPB through activation of the complement system, coagulation pathways, leukocytes, and the release of inflammatory cytokines. Local inflammation in the brain and kidney may be aggravated by ischemia (and thus hypoxia) and reperfusion (and thus oxidative stress) and activation of resident and infiltrating inflammatory cells. Various strategies, including manipulating perfusion conditions and administration of pharmacotherapies, could potentially be deployed to avoid or attenuate hypoxia and inflammation during CPB. Regarding manipulating perfusion conditions, based on experimental and clinical data, increasing standard pump flow and arterial pressure during CPB appears to offer the best hope to avoid hypoxia and injury, at least in the kidney. Pharmacological approaches, including use of anti-inflammatory agents such as dexmedetomidine and erythropoietin, have shown promise in preclinical models but have not been adequately tested in human trials. However, evidence for beneficial effects of corticosteroids on renal and neurological outcomes is lacking. © 2021 American Physiological Society. Compr Physiol 11:1-36, 2021.

Isoflurane not at the expense of postoperative nausea and vomiting in cardiac anesthesia - an observational study

OBJECTIVES

Inhalative anesthesia is of common use, but is generally known to potentiate postoperative nausea and vomiting (PONV). With an internal change of anesthesia regimen from total intravenous anesthesia (TIVA) to isoflurane (in terms of myocardial protection) in cardiac anesthesia a higher incidence of PONV was to be expected. Therefore, we evaluated the incidence of PONV after the simultaneous implementation of PONV prophylaxis.

METHODS

The incidence of PONV, prospectively assessed in 197 cardiac surgery patients (68 y ± 10.4, 66.5% male) having isoflurane plus dual PONV prophylaxis with dexamethasone and droperidol, was compared with previous data of 190 controls (67 y ± 9.6, 71% male) having TIVA without and with single or dual PONV prophylaxis (n = 64 dexamethasone and droperidol, n = 25 dexamethasone, n = 101 only TIVA), and the Apfel-scoring (0-4 depending on PONV-risk). DRKS00014275. Statistics: Chi²-test, p < .05 (Bonferroni).

RESULTS

The incidence of PONV under isoflurane with antiemetic prophylaxis was 20.8% (95% confidence interval (CI) 15.4; 27.4) compared to 30.5% (95%CI 24; 37.6) under TIVA (p = .029; dexamethasone and droperidol 23.4% (95%CI 13.8; 35.7); dexamethasone 32% (95%CI 14.9; 53.5); only TIVA 34.7% (95%CI 25.5; 44.8)), but was not lower in high-risk patients than predicted according to Apfel-scoring 4 (71.4 vs. 78%).

CONCLUSION

In cardiac anesthesia, the use of isoflurane is not at the expense of PONV when using a risk-independent two-drug-prophylaxis. It is even beneficial resulting surprisingly in a lower incidence of PONV than under TIVA unless with and without prophylaxis. Patients with the highest risk for PONV and receiving isoflurane should receive a third antiemetic prophylactic drug.

Isoflurane alleviates hypoxia/reoxygenation induced myocardial injury by reducing miR-744 mediated SIRT6

BACKGROUND

The objective of this study was to investigate the role of miR-744 and its target genes in ISO protection against hypoxia/reoxygenation (H/R) induced myocardial injury.

METHODS

Rat cardiomyocytes H9c2 was used to establish an H/R model in vitro, and the level of miR-744 mRNA was detected by fluorescence quantitative PCR. CCK-8 and flow cytometry was used to detected cell viability and apoptosis. Myocardial injury markers CK-MB, cTnI, and LDH were detected by enzyme-linked immunosorbent assay (ELISA). Online bioinformatics software miRDB and miRWalk predicts miR-744 target and its potential binding site, and verifies the target by luciferase reporter assay.

RESULTS

After H/R induction, miR-744 mRNA level was remarkedly increased, cell viability was deceased, and apoptosis was increased (p < 0.05). Myocardial injury markers CK-MB, cTnI, and LDH expressions were also increased (p < 0.05). However, ISO pretreatment can significantly alleviate the decrease in cell viability induced by H/R, the increase of cell apoptosis, and the increase of myocardial injury markers, and it play a cardioprotective effect (p < 0.05). More importantly, elevated miR-744 remarkedly weakened the protective effect of ISO on H/R-induced myocardial injury, resulting in decreased cell viability, increased apoptosis, and elevated concentration of myocardial injury indicators (p < 0.05). Luciferase reporter assay confirmed that Sirtuins6 (SIRT6) is a potential target of miR-744 and decreased in H/R-induced myocardial injury, and ISO exposure can reverse its level (p < 0.05).

CONCLUSION

Our findings provide new insights that ISO pretreatment can remarkedly regulate miR-744 and its downstream target SIRT6 to mitigate myocardial injury induced by H/R.

Longitudinal impact on rat cardiac tissue transcriptomic profiles due to acute intratracheal inhalation exposures to isoflurane

Isoflurane (ISO) is a widely used inhalation anesthetic in experiments with rodents and humans during surgery. Though ISO has not been reported to impart long-lasting side effects, it is unknown if ISO can influence gene regulation in certain tissues, including the heart. Such changes could have important implications for use of this anesthetic in patients susceptible to heart failure/other cardiac abnormalities. To test if ISO could alter gene regulation/expression in heart tissues, and if such changes were reversible, prolonged, or late onset with time, SHR (spontaneously hypertensive) rats were exposed by intratracheal inhalation to a 97.5% air/2.5% ISO mixture on two consecutive days (2 hr/d). Control rats breathed filtered air only. On Days 1, 30, 240, and 360 post-exposure, rat hearts were collected and total RNA was extracted from the left ventricle for global gene expression analysis. The data revealed differentially-expressed genes (DEG) in response to ISO (compared to naïve control) at all post-exposure timepoints. The data showed acute ISO exposures led to DEG associated with wounding, local immune function, inflammation, and circadian rhythm regulation at Days 1 and 30; these effects dissipated by Day 240. There were other significantly-increased DEG induced by ISO at Day 360; these included changes in expression of genes associated with cell signaling, differentiation, and migration, extracellular matrix organization, cell-substrate adhesion, heart development, and blood pressure regulation. Examination of consistent DEG at Days 240 and 360 indicated late onset DEG reflecting potential long-lasting effects from ISO; these included DEG associated with oxidative phosphorylation, ribosome, angiogenesis, mitochondrial translation elongation, and focal adhesion. Together, the data show acute repeated ISO exposures could impart variable effects on gene expression/regulation in the heart. While some alterations self-resolved, others appeared to be long-lasting or late onset. Whether such changes occur in all rat models or in humans remains to be investigated.

Effects of propofol and its formulation components on macrophages and neutrophils in obese and lean animals

We hypothesized whether propofol or active propofol component (2,6-diisopropylphenol [DIPPH] and lipid excipient [LIP-EXC]) separately may alter inflammatory mediators expressed by macrophages and neutrophils in lean and obese rats. Male Wistar rats (n = 10) were randomly assigned to receive a standard (lean) or obesity-inducing diet (obese) for 12 weeks. Animals were euthanized, and alveolar macrophages and neutrophils from lean and obese animals were exposed to propofol (50 µM), active propofol component (50 µM, 2,6-DIPPH), and lipid excipient (soybean oil, purified egg phospholipid, and glycerol) for 1 h. The primary outcome was IL-6 expression after propofol and its components exposure by alveolar macrophages extracted from bronchoalveolar lavage fluid. The secondary outcomes were the production of mediators released by macrophages from adipose tissue, and neutrophils from lung and adipose tissues, and neutrophil migration. IL-6 increased after the exposure to both propofol (median [interquartile range] 4.14[1.95-5.20]; p = .04) and its active component (2,6-DIPPH) (4.09[1.67-5.91]; p = .04) in alveolar macrophages from obese animals. However, only 2,6-DIPPH increased IL-10 expression (7.59[6.28-12.95]; p = .001) in adipose tissue-derived macrophages. Additionally, 2,6-DIPPH increased C-X-C chemokine receptor 2 and 4 (CXCR2 and CXCR4, respectively) in lung (10.08[8.23-29.01]; p = .02; 1.55[1.49-3.43]; p = .02) and adipose tissues (8.78[4.15-11.57]; p = .03; 2.86[2.17-3.71]; p = .01), as well as improved lung-derived neutrophil migration (28.00[-3.42 to 45.07]; p = .001). In obesity, the active component of propofol affected both the M1 and M2 markers as well as neutrophils in both alveolar and adipose tissue cells, suggesting that lipid excipient may hinder the effects of active propofol.

Volatile Versus Intravenous Anesthetics in Cardiac Anesthesia: a Narrative Review

Purpose of the Review

The present review addresses clinicians and gives an overview about the experimental rationale for pharmacological conditioning associated with volatile anesthetics, opioids, and propofol; the current clinical data; and the technical considerations regarding the clinical routine in cardiac anesthesia.

Recent Findings

Volatile anesthetics have been standard of care for general anesthesia for cardiac surgery, especially while using cardiopulmonary bypass. The 2019 published MYRIAD trial was not able to show a difference in mortality or cardiac biomarkers for volatile anesthetics compared to total intravenous anesthesia (TIVA), raising the question of equivalence with respect to patient outcome.

Summary

Reviewing the literature, the scientific foundation for the belief of clinically relevant conditioning by uninterrupted administration of a volatile anesthetic is weak. TIVA can also be performed safely in patients undergoing cardiac surgery.

[Inhalational anesthetics]

Inhalational anesthetics have been used for induction and maintenance of general anesthesia for more than 150 years. All of the currently used inhalational anesthetics are chlorinated and fluorinated derivatives of ether. Dosing is carried out using the minimal alveolar concentration (MAC) concept. The pharmacokinetic properties of the various inhalational anesthetics are governed by the specific distribution coefficients. Mechanisms of action include specific modulations of various receptors of the central nervous system as well as an unspecific interaction with the cell membrane. Organ toxicity of modern inhalational anesthetics is considered to be minimal. The role of inhalational anesthetics in the context of postoperative nausea and vomiting (PONV) has been reassessed in recent years. The superiority of inhalational anesthetics over intravenous hypnotics with respect to intraoperative awareness is undisputed. The organ protective mechanism of preconditioning is an exclusive property of inhalational anesthetics among all the currently available hypnotics.

Tailored anaesthesia for thoracoscopic surgery promoting enhanced recovery: The state of the art

PURPOSE OF THE REVIEW

The current review focuses on precise anaesthesia for video-assisted thoracoscopic surgery (VATS) with the goal of enhanced recovery. The main aim of an enhanced recovery program after thoracic surgery is to reduce postoperative stress response, protect from postoperative pulmonary complications, give hospitals a better financial option and improve overall patient outcome. This can ultimately reduce hospital stay and increase patient satisfaction. With advances in endoscopic, robotic and endovascular techniques, video-assisted thoracoscopic surgery (VATS) can be performed in a minimally invasive way in managing most pulmonary, pleural and mediastinal diseases. As a minimally invasive technique, video-assisted thoracoscopic surgery (VATS) represents an important element of enhanced recovery program in thoracic surgery as it can achieve most of its goals. Anaesthetic management during preoperative, intraoperative and postoperative period is essential for the establishment of a successful enhanced recovery program. In the era of enhanced recovery protocols, non-intubated thoracoscopic procedures present a step forward. This article focuses on the key anaesthetic elements of the enhanced recovery program during all phases of thoracoscopic surgery. Having reviewed recent literature, a systematic review of literature will highlight successful ERAS protocols published for thoracoscopic surgery.

Inhaled Anesthetics: Environmental Role, Occupational Risk, and Clinical Use

Inhaled anesthetics have been in clinical use for over 150 years and are still commonly used in daily practice. The initial view of inhaled anesthetics as indispensable for general anesthesia has evolved during the years and, currently, its general use has even been questioned. Beyond the traditional risks inherent to any drug in use, inhaled anesthetics are exceptionally strong greenhouse gases (GHG) and may pose considerable occupational risks. This emphasizes the importance of evaluating and considering its use in clinical practices. Despite the overwhelming scientific evidence of worsening climate changes, control measures are very slowly implemented. Therefore, it is the responsibility of all society sectors, including the health sector to maximally decrease GHG emissions where possible. Within the field of anesthesia, the potential to reduce GHG emissions can be briefly summarized as follows: Stop or avoid the use of nitrous oxide (N2O) and desflurane, consider the use of total intravenous or local-regional anesthesia, invest in the development of new technologies to minimize volatile anesthetics consumption, scavenging systems, and destruction of waste gas. The improved and sustained awareness of the medical community regarding the climate impact of inhaled anesthetics is mandatory to bring change in the current practice.

Newer Volatile Anesthetic Agents in Cardiac Anesthesia: Review of Literature

Myocardial protection with volatile anesthetic agents have been suggested by multiple studies. These studies, however, are scattered and are often limited to a particular aspect of cardiac anesthesia. Older inhalational agents like halothane is known to cause significant hepatic damage in patients undergoing long duration surgeries while isoflurane is known to have marked vasodilating properties that also affects the coronary arteries leading to coronary “steal” phenomenon. Additionally, newer agents, like sevoflurane and desflurane, have shown more prominent cardioprotective effects than older agents. We searched ScholarOne, Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library. The medical subject headings (MeSH) terms “anaesthesia, inhalational,” “anaesthesia, intravenous, or TIVA,” and “Cardiac anaesthesia or Cardiac Surgery” were used. Additional studies were identified by review of the reference sections of all eligible studies. The aim of this review article is to bring together the evidences with newer inhalational agents and provide a holistic view of their benefits and shortcomings in cardiac anesthesia.

Pharmacological Conditioning of the Heart: An Update on Experimental Developments and Clinical Implications

The aim of pharmacological conditioning is to protect the heart against myocardial ischemia-reperfusion (I/R) injury and its consequences. There is extensive literature that reports a multitude of different cardioprotective signaling molecules and mechanisms in diverse experimental protocols. Several pharmacological agents have been evaluated in terms of myocardial I/R injury. While results from experimental studies are immensely encouraging, translation into the clinical setting remains unsatisfactory. This narrative review wants to focus on two aspects: (1) give a comprehensive update on new developments of pharmacological conditioning in the experimental setting concentrating on recent literature of the last two years and (2) briefly summarize clinical evidence of these cardioprotective substances in the perioperative setting highlighting their clinical implications. By directly opposing each pharmacological agent regarding its recent experimental knowledge and most important available clinical data, a clear overview is given demonstrating the remaining gap between basic research and clinical practice. Finally, future perspectives are given on how we might overcome the limited translatability in the field of pharmacological conditioning.