Insulin and glycolysis dependency of cardioprotection by nicotinamide riboside

Decreased nicotinamide adenine dinucleotide (NAD+) levels contribute to various pathologies such as ageing, diabetes, heart failure and ischemia-reperfusion injury (IRI). Nicotinamide riboside (NR) has emerged as a promising therapeutic NAD+ precursor due to efficient NAD+ elevation and was recently shown to be the only agent able to reduce cardiac IRI in models employing clinically relevant anesthesia. However, through which metabolic pathway(s) NR mediates IRI protection remains unknown. Furthermore, the influence of insulin, a known modulator of cardioprotective efficacy, on the protective effects of NR has not been investigated. Here, we used the isolated mouse heart allowing cardiac metabolic control to investigate: (1) whether NR can protect the isolated heart against IRI, (2) the metabolic pathways underlying NR-mediated protection, and (3) whether insulin abrogates NR protection. NR protection against cardiac IRI and effects on metabolic pathways employing metabolomics for determination of changes in metabolic intermediates, and 13C-glucose fluxomics for determination of metabolic pathway activities (glycolysis, pentose phosphate pathway (PPP) and mitochondrial/tricarboxylic acid cycle (TCA cycle) activities), were examined in isolated C57BL/6N mouse hearts perfused with either (a) glucose + fatty acids (FA) ("mild glycolysis group"), (b) lactate + pyruvate + FA ("no glycolysis group"), or (c) glucose + FA + insulin ("high glycolysis group"). NR increased cardiac NAD+ in all three metabolic groups. In glucose + FA perfused hearts, NR reduced IR injury, increased glycolytic intermediate phosphoenolpyruvate (PEP), TCA intermediate succinate and PPP intermediates ribose-5P (R5P) / sedoheptulose-7P (S7P), and was associated with activated glycolysis, without changes in TCA cycle or PPP activities. In the "no glycolysis" hearts, NR protection was lost, whereas NR still increased S7P. In the insulin hearts, glycolysis was largely accelerated, and NR protection abrogated. NR still increased PPP intermediates, with now high 13C-labeling of S7P, but NR was unable to increase metabolic pathway activities, including glycolysis. Protection by NR against IRI is only present in hearts with low glycolysis, and is associated with activation of glycolysis. When activation of glycolysis was prevented, through either examining "no glycolysis" hearts or "high glycolysis" hearts, NR protection was abolished. The data suggest that NR's acute cardioprotective effects are mediated through glycolysis activation and are lost in the presence of insulin because of already elevated glycolysis.

Preoperative Glycosylated Haemoglobin Screening to Identify Older Adult Patients with Undiagnosed Diabetes Mellitus-A Retrospective Cohort Study

More than 25% of older adults in Europe have diabetes mellitus. It is estimated that 45% of patients with diabetes are currently undiagnosed, which is a known risk factor for perioperative morbidity. We investigated whether routine HbA1c screening in older adult patients undergoing surgery would identify patients with undiagnosed diabetes. We included patients aged ≥65 years without a diagnosis of diabetes who visited the preoperative assessment clinic at the Amsterdam University Medical Center and underwent HbA1c screening within three months before surgery. Patients undergoing cardiac surgery were excluded. We assessed the prevalence of undiagnosed diabetes (defined as HbA1c ≥ 48 mmol·mol-1) and prediabetes (HbA1c 39-47 mmol·mol-1). Using a multivariate regression model, we analysed the ability of HbA1c to predict days alive and at home within 30 days after surgery. From January to December 2019, we screened 2015 patients ≥65 years at our clinic. Of these, 697 patients without a diagnosis of diabetes underwent HbA1c screening. The prevalence of undiagnosed diabetes and prediabetes was 3.7% (95%CI 2.5-5.4%) and 42.9% (95%CI 39.2-46.7%), respectively. Preoperative HbA1c was not associated with days alive and at home within 30 days after surgery. In conclusion, we identified a small number of patients with undiagnosed diabetes and a high prevalence of prediabetes based on preoperative HbA1c screening in a cohort of older adults undergoing non-cardiac surgery. The relevance of prediabetes in the perioperative setting is unclear. Screening for HbA1c in older adult patients undergoing non-cardiac surgery does not appear to help predict postoperative outcome.

Empagliflozin prevents oxidative stress in human coronary artery endothelial cells via the NHE/PKC/NOX axis

BACKGROUND

Empagliflozin (EMPA) ameliorates reactive oxygen species (ROS) generation in human endothelial cells (ECs) exposed to 10 % stretch, but the underlying mechanisms are still unclear. Pathological stretch is supposed to stimulate protein kinase C (PKC) by increasing intracellular calcium (Ca2+), therefore activating nicotinamide adenine dinucleotide phosphate oxidase (NOX) and promoting ROS production in human ECs. We hypothesized that EMPA inhibits stretch-induced NOX activation and ROS generation through preventing PKC activation.

METHODS

Human coronary artery endothelial cells (HCAECs) were pre-incubated for 2 h before exposure to cyclic stretch (5 % or 10 %) with either vehicle, EMPA or the PKC inhibitor LY-333531 or PKC siRNA. PKC activity, NOX activity and ROS production were detected after 24 h. Furthermore, the Ca2+ chelator BAPTA-AM, NCX inhibitor ORM-10962 or NCX siRNA, sodium/potassium pump inhibitor ouabain and sodium hydrogen exchanger (NHE) inhibitor cariporide were applied to explore the involvement of the NHE/Na+/NCX/Ca2+ in the ROS inhibitory capacity of EMPA.

RESULTS

Compared to 5 % stretch, 10 % significantly increased PKC activity, which was reduced by EMPA and PKC inhibitor LY-333531. EMPA and LY-333531 showed a similar inhibitory capacity on NOX activity and ROS generation induced by 10 % stretch, which was not augmented by combined treatment with both drugs. PKC-β knockdown inhibits the NOX activation induced by Ca2+ and 10 % stretch. BAPTA, pharmacologic or genetic NCX inhibition and cariporide reduced Ca2+ in static HCAECs and prevented the activation of PKC and NOX in 10%-stretched cells. Ouabain increased ROS generation in cells exposed to 5 % stretch.

CONCLUSION

EMPA reduced NOX activity via attenuation of the NHE/Na+/NCX/Ca2+/PKC axis, leading to less ROS generation in HCAECs exposed to 10 % stretch.

Introduction of a Post-Anaesthesia Care Unit in a Teaching Hospital Is Associated with a Reduced Length of Hospital Stay in Noncardiac Surgery: A Single-Centre Interrupted Time Series Analysis

BACKGROUND

A post-anaesthesia care unit (PACU) may improve postoperative care compared with intermediate care units (IMCU) due to its dedication to operative care and an individualized duration of postoperative stay. The effects of transition from IMCU to PACU for postoperative care following intermediate to high-risk noncardiac surgery on length of hospital stay, intensive care unit (ICU) utilization, and postoperative complications were investigated.

METHODS

This single-centre interrupted time series analysis included patients undergoing eleven different noncardiac surgical procedures associated with frequent postoperative admissions to an IMCU or PACU between January 2018 and March 2019 (IMCU episode) and between October 2019 and December 2020 (PACU episode). Primary outcome was hospital length of stay, secondary outcomes included postoperative complications and ICU admissions.

RESULTS

In total, 3300 patients were included. The hospital length of stay was lower following PACU admission compared to IMCU admission (IMCU 7.2 days [4.2-12.0] vs. PACU 6.0 days [3.6-9.1]; p < 0.001). Segmented regression analysis demonstrated that the introduction of the PACU was associated with a decrease in hospital length of stay (GMR 0.77 [95% CI 0.66-0.91]; p = 0.002). No differences between episodes were detected in the number of postoperative complications or postoperative ICU admissions.

CONCLUSIONS

The introduction of a PACU for postoperative care of patients undergoing intermediate to high-risk noncardiac surgery was associated with a reduction in the length of stay at the hospital, without increasing postoperative complications.

Surveillance of high-risk early postsurgical patients for real-time detection of complications using wireless monitoring (SHEPHERD study): results of a randomized multicenter stepped wedge cluster trial

Background

Vital signs measurements on the ward are performed intermittently. This could lead to failure to rapidly detect patients with deteriorating vital signs and worsens long-term outcome. The aim of this study was to test the hypothesis that continuous wireless monitoring of vital signs on the postsurgical ward improves patient outcome.

Methods

In this prospective, multicenter, stepped-wedge cluster randomized study, patients in the control group received standard monitoring. The intervention group received continuous wireless monitoring of heart rate, respiratory rate and temperature on top of standard care. Automated alerts indicating vital signs deviation from baseline were sent to ward nurses, triggering the calculation of a full early warning score followed. The primary outcome was the occurrence of new disability three months after surgery.

Results

The study was terminated early (at 57% inclusion) due to COVID-19 restrictions. Therefore, only descriptive statistics are presented. A total of 747 patients were enrolled in this study and eligible for statistical analyses, 517 patients in the control group and 230 patients in the intervention group, the latter only from one hospital. New disability at three months after surgery occurred in 43.7% in the control group and in 39.1% in the intervention group (absolute difference 4.6%).

Conclusion

This is the largest randomized controlled trial investigating continuous wireless monitoring in postoperative patients. While patients in the intervention group seemed to experience less (new) disability than patients in the control group, results remain inconclusive with regard to postoperative patient outcome due to premature study termination.

Clinical trial registration

ClinicalTrials.gov, ID: NCT02957825.

Computer tomography perfusion patterns in iatrogenic cerebral arterial gas embolism: A retrospective cohort study

PURPOSE

Cerebral arterial gas embolism (CAGE) occurs when air or medical gas enters the systemic circulation during invasive procedures and lodges in the cerebral vasculature. Non-contrast computer tomography (CT) may not always show intracerebral gas. CT perfusion (CTP) might be a useful adjunct for diagnosing CAGE in these patients.

METHODS

This is a retrospective single-center cohort study. We included patients who were diagnosed with iatrogenic CAGE and underwent CTP within 24 h after onset of symptoms between January 2016 and October 2022. All imaging studies were evaluated by two independent radiologists. CTP studies were scored semi-quantitatively for perfusion abnormalities (normal, minimal, moderate, severe) in the following parameters: cerebral blood flow, cerebral blood volume, time-to-drain and time-to-maximum.

RESULTS

Among 27 patient admitted with iatrogenic CAGE, 15 patients underwent CTP within the designated timeframe and were included for imaging analysis. CTP showed perfusion deficits in all patients except one. The affected areas on CTP scans were in general located bilaterally and frontoparietally. The typical pattern of CTP abnormalities in these areas was hypoperfusion with an increased time-to-drain and time-to-maximum, and a corresponding minimal decrease in cerebral blood flow. Cerebral blood volume was mostly unaffected.

CONCLUSION

CTP may show specific perfusion defects in patients with a clinical diagnosis of CAGE. This suggests that CTP may be supportive in diagnosing CAGE in cases where no intracerebral gas is seen on non-contrast CT.

Initiatives to detect and prevent death from perioperative deterioration

PURPOSE OF REVIEW

This study indicates that there are differences between hospitals in detection, as well as in adequate management of postsurgical complications, a phenomenon that is described as 'failure-to-rescue'.In this review, recent initiatives to reduce failure-to-rescue in the perioperative period are described.

RECENT FINDINGS

Use of cognitive aids, emergency manuals, family participation as well as remote monitoring systems are measures to reduce failure-to-rescue situations. Postoperative visit of an anaesthesiologist on the ward was not shown to improve outcome, but there is still room for improvement of postoperative care.

SUMMARY

Improving the complete emergency chain, including monitoring, recognition and response in the afferent limb, as well as diagnostic and treatment in the efferent limb, should lead to reduced failure-to-rescue situations in the perioperative period.

Crisis Scenarios for Simulation-Based Nontechnical Skills Training for Cardiac Surgery Teams: A National Survey Among Cardiac Anesthesiologists, Cardiac Surgeons, Clinical Perfusionists, and Cardiac Operating Room Nurses

BACKGROUND

Nontechnical skills in cardiac surgery are vital in ensuring patient safety in the operating room (OR). To train these skills in a simulation-based scenario, a collection of commonly accepted crisis scenarios is needed to serve as a framework for a simulation-based training program.

OBJECTIVE

The objective of this study was to identify and reach consensus on a collection of relevant crisis scenarios in cardiac surgery suitable for simulation-based team training focusing on nontechnical skills.

METHODS

Using the Delphi method, a national assessment was performed among cardiac surgeons, cardiac anesthesiologists, clinical perfusionists, and cardiac OR nurses in the Netherlands. In the first Delphi round, potential crisis scenarios for simulation-based team training in cardiac surgery were identified. In the second round, the identified scenarios were rated using a 5-point Likert scale. Finally, based on consensus (two-thirds majority), scenarios were prioritized and explored for feasibility.

RESULTS

One hundred fourteen experts participated in the study (26 cardiac anesthesiologists, 24 cardiac surgeons, 25 clinical perfusionists, and 39 OR nurses), representing all 16 cardiac surgical centers in the Netherlands. In the first round, 237 scenarios were identified. After eliminating duplicates and grouping similar scenarios, 44 scenarios were scored in round 2, which finally resulted in 13 relevant crisis scenarios with an expert consensus higher than 67%.

CONCLUSIONS

Thirteen crisis scenarios relevant to simulation-based team training were identified by an expert panel consisting of all members of the cardiac surgical team. Further research is needed to evaluate the educational value of the respective scenarios.

Is a preoperative multidisciplinary team meeting (cost)effective to improve outcome for high-risk adult patients undergoing noncardiac surgery: the PREPARATION study-a multicenter stepped-wedge cluster randomized trial

BACKGROUND

As a result of increased life expectancy and improved care for patients suffering from chronic disease, the number of patients with multimorbidity requiring surgical intervention is increasing. For complex surgical patients, it is essential to balance the potential benefits of surgical treatment against the risk of permanent loss of functional capacity and quality of life due to complications. European and US guidelines on perioperative care recommend preoperative multidisciplinary team (MDT) discussions for high-risk noncardiac surgical patients. However, the evidence underlying benefits from preoperative MDT meetings with all relevant perioperative specialties present is limited. The current study aims to investigate the effect of implementation of preoperative MDT discussions for high-risk patients undergoing noncardiac surgery on serious adverse events.

METHODS/DESIGN

PREPARATION is a stepped-wedge cluster randomized trial in 14 Dutch hospitals without currently established preoperative MDT meeting. The intervention, preoperative MDT meetings, will be implemented sequentially with seven blocks of 2 hospitals switching from control (preoperative screening as usual) to the intervention every 3 months. Each hospital will be randomized to one of seven blocks. We aim to include 1200 patients. The primary outcome is the incidence of serious adverse events at 6 months. Secondary outcomes include (cost)effectiveness, functional outcome, and quality of life for up to 12 months.

DISCUSSION

PREPARATION is the first study to assess the effectiveness of a preoperative MDT meeting for high-risk noncardiac surgical patients in the presence of an anesthesiologist. If the results suggest that preoperative MDT discussions for high-risk patients are (cost)-effective, the current study facilitates implementation of preoperative MDT meetings in clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05703230. Registered on 11/09/2022.

International Survey on Perioperative Management of Patients With Infective Endocarditis

OBJECTIVES

To estimate the current practice in the perioperative management of patients undergoing cardiac surgery due to infective endocarditis.

DESIGN

A prospective, open, 24-item, web-based cross-sectional survey.

SETTING

Online survey endorsed by the European Association of Cardiothoracic Anesthesiology and Intensive Care (EACTAIC).

PARTICIPANTS

Members of the EACTAIC.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 156 responses from 44 countries were received, with a completion rate of 99%. The response rate was 16.6%. Most respondents (76%) practiced cardiac anesthesia in European hospitals, and most respondents stated that a multidisciplinary endocarditis team was not established at their center, that cardiac anesthesiologists appeared to be involved infrequently in those teams (36%), and that they were not involved in decision-making on indication and timing of surgery (88%). In contrast, the cardiac anesthesiologist performed intraoperative antibiotic therapy (62%) and intraoperative transesophageal echocardiography (90%). Furthermore, there was a relative heterogeneity concerning perioperative monitoring, as well as for coagulation and transfusion management.

CONCLUSIONS

This international survey evaluated current practice among cardiac anesthesiologists in the perioperative management of patients with infective endocarditis and the anesthesiologist's role in multidisciplinary decision-making. Heterogeneity in treatment approaches was identified, indicating relevant knowledge gaps that should encourage further clinical research to optimize treatment and postoperative outcomes in this specific population.

Perioperative Complications in Infective Endocarditis

Infective endocarditis is a challenging condition to manage, requiring collaboration among various medical professionals. Interdisciplinary teamwork within endocarditis teams is essential. About half of the patients diagnosed with the disease will ultimately have to undergo cardiac surgery. As a result, it is vital for all healthcare providers involved in the perioperative period to have a comprehensive understanding of the unique features of infective endocarditis, including clinical presentation, echocardiographic signs, coagulopathy, bleeding control, and treatment of possible organ dysfunction. This narrative review provides a summary of the current knowledge on the incidence of complications and their management in the perioperative period in patients with infective endocarditis.

Does Regular Practice with a "Flexible Bronchoscopy Simulator" Improve Fibreoptic Intubation Skills in Experts and Novices? A Randomized Controlled Study

BACKGROUND

The appropriate management of a "difficult airway" remains a challenge for novices and experienced anaesthetists. With the current available airway technologies, e.g., video laryngoscopy, flexible bronchoscopy (fibreoptic intubation (FOI)) for endotracheal intubation is decreasing, likely diminishing caregiver skills. We investigated whether bronchoscopy simulator training improved FOI skills.

METHODS

72 volunteers, consisting of anaesthetists, anaesthesia residents, and nurses, performed six exercises on a bronchoscopy simulator. At baseline and after 12 months, the six exercises included one serious game (to train agility), two basic airways, and three difficult airways. After a baseline assessment, subjects were randomly allocated to the intervention group (with) or control group without bronchoscopy simulator training every six weeks for 10 min using a preloaded serious game. The primary outcome was the difference in the time to reach the carina after 12 months, as measured objectively by the simulator. The level of stress and FOI confidence after 12 months were secondary outcomes.

RESULTS

The control and intervention groups had a similar time to reach the carina in difficult airway cases and the reported stress levels, at baseline and 12 months, showed no difference. In contrast, the intervention group's self-reported confidence in FOI skills improved more.

CONCLUSIONS

Although participants rated higher in confidence, practicing FOI skills on an airway simulator with an agility game did not increase their performance in simulated challenging airway instances.

Early hyperbaric oxygen therapy is associated with favorable outcome in patients with iatrogenic cerebral arterial gas embolism: systematic review and individual patient data meta-analysis of observational studies

BACKGROUND

Iatrogenic cerebral arterial gas embolism (CAGE) caused by invasive medical procedures may be treated with hyperbaric oxygen therapy (HBOT). Previous studies suggested that initiation of HBOT within 6-8 h is associated with higher probability of favorable outcome, when compared to time-to-HBOT beyond 8 h. We performed a group level and individual patient level meta-analysis of observational studies, to evaluate the relationship between time-to-HBOT and outcome after iatrogenic CAGE.

METHODS

We systematically searched for studies reporting on time-to-HBOT and outcome in patients with iatrogenic CAGE. On group level, we meta-analyzed the differences between median time-to-HBOT in patients with favorable versus unfavorable outcome. On individual patient level, we analyzed the relationship between time-to-HBOT and probability of favorable outcome in a generalized linear mixed effects model.

RESULTS

Group level meta-analysis (ten studies, 263 patients) shows that patients with favorable outcome were treated with HBOT 2.4 h (95% CI 0.6-9.7) earlier than patients with unfavorable outcome. The generalized linear mixed effects model (eight studies, 126 patients) shows a significant relationship between time-to-HBOT and probability of favorable outcome (p = 0.013) that remains significant after correcting for severity of manifestations (p = 0.041). Probability of favorable outcome decreases from approximately 65% when HBOT is started immediately, to 30% when HBOT is delayed for 15 h.

CONCLUSIONS

Increased time-to-HBOT is associated with decreased probability of favorable outcome in iatrogenic CAGE. This suggests that early initiation of HBOT in iatrogenic CAGE is of vital importance.

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.

Comparison of Patient-Controlled versus Continuous Epidural Analgesia in Adult Surgical Patients: A Systematic Review

BACKGROUND

The advantages of PCEA over CEA have been demonstrated in obstetric patients. Whether a similar benefit applies to surgical patients is unclear.

METHODS

Embase, PubMed, and Cochrane Library were searched, enabling a systematic review of studies comparing PCEA and CEA in adult surgical patients (PROSPERO: CRD42018106644). The study quality was assessed using the Cochrane risk-of-bias tool (RoB2). The primary outcome was pain scores on postoperative day one (POD1). Secondary outcomes were 24 or 48 h epidural or intravenous total analgesic dose, systemic analgesics, manual top-ups, side effects, and patient satisfaction.

RESULTS

Six randomized controlled trials with high heterogeneity of study characteristics were identified with a moderate risk of bias. Two studies showed significantly reduced resting pain scores on POD1 in PCEA compared with CEA patients (36-44%, p < 0.05). Four studies found comparable pain scores between these groups. PCEA use reduced epidural medication (28% to 40% reduction, p < 0.01) in four studies. One study found a 23% reduction (p < 0.001) of top-ups in PCEA; intravenous morphine use by PCEA patients was reduced (0.16 vs. 3.45 mg per patient, p < 0.05) in one study. PCEA patients were more satisfied with analgesia (p < 0.001) in two studies. Nausea and vomiting were reduced in PCEA (p = 0.01).

CONCLUSIONS

Regarding the reduction in pain scores, the effects of PCEA were not significant or clinically not relevant. However, regarding the amount of epidural drug use, the amount of required rescue systemic analgesics, patient satisfaction, and the number of required top-ups, PCEA had advantages over CEA in surgical patients.

Canagliflozin inhibits inflammasome activation in diabetic endothelial cells - Revealing a novel calcium-dependent anti-inflammatory effect of canagliflozin on human diabetic endothelial cells

BACKGROUND

Canagliflozin (CANA) shows anti-inflammatory and anti-oxidative effects on endothelial cells (ECs). In diabetes mellitus (DM), excessive reactive oxygen species (ROS) generation, increased intracellular calcium (Ca²⁺) and enhanced extracellular signal regulated kinase (ERK) 1/2 phosphorylation are crucial precursors for inflammasome activation. We hypothesized that: (1) CANA prevents the TNF-α triggered ROS generation in ECs from diabetic donors and in turn suppresses the inflammasome activation; and (2) the anti-inflammatory effect of CANA is mediated via intracellular Ca²⁺ and ERK1/2.

METHODS

Human coronary artery endothelial cells from donors with DM (D-HCAECs) were pre-incubated with either CANA or vehicle for 2 h before exposure to 50 ng/ml TNF-α for 2-48 h. NAC was applied to scavenge ROS, BAPTA-AM to chelate intracellular Ca²⁺, and PD 98059 to inhibit the activation of ERK1/2. Live cell imaging was performed at 6 h to measure ROS and intracellular Ca²⁺. At 48 h, ELISA and infra-red western blot were applied to detect IL-1β, NLRP3, pro-caspase-1 and ASC.

RESULTS

10 µM CANA significantly reduced TNF-α related ROS generation, IL-1β production and NLRP3 expression (P all <0.05), but NAC did not alter the inflammasome activation (P > 0.05). CANA and BAPTA both prevented intracellular Ca²⁺ increase in cells exposed to TNF-α (P both <0.05). Moreover, BAPTA and PD 98059 significantly reduced the TNF-α triggered IL-1β production as well as NLRP3 and pro-caspase-1 expression (P all <0.05).

CONCLUSION

CANA suppresses inflammasome activation by inhibition of (1) intracellular Ca²⁺ and (2) ERK1/2 phosphorylation, but not by ROS reduction.

Performance and usability of pre-operative prediction models for 30-day peri-operative mortality risk: a systematic review

Estimating pre-operative mortality risk may inform clinical decision-making for peri-operative care. However, pre-operative mortality risk prediction models are rarely implemented in routine clinical practice. High predictive accuracy and clinical usability are essential for acceptance and clinical implementation. In this systematic review, we identified and appraised prediction models for 30-day postoperative mortality in non-cardiac surgical cohorts. PubMed and Embase were searched up to December 2022 for studies investigating pre-operative prediction models for 30-day mortality. We assessed predictive performance in terms of discrimination and calibration. Risk of bias was evaluated using a tool to assess the risk of bias and applicability of prediction model studies. To further inform potential adoption, we also assessed clinical usability for selected models. In all, 15 studies evaluating 10 prediction models were included. Discrimination ranged from a c-statistic of 0.82 (MySurgeryRisk) to 0.96 (extreme gradient boosting machine learning model). Calibration was reported in only six studies. Model performance was highest for the surgical outcome risk tool (SORT) and its external validations. Clinical usability was highest for the surgical risk pre-operative assessment system. The SORT and risk quantification index also scored high on clinical usability. We found unclear or high risk of bias in the development of all models. The SORT showed the best combination of predictive performance and clinical usability and has been externally validated in several heterogeneous cohorts. To improve clinical uptake, full integration of reliable models with sufficient face validity within the electronic health record is imperative.

Comparison of Postoperative Neurocognitive Function in Older Adult Patients with and without Diabetes Mellitus

INTRODUCTION

Delayed neurocognitive recovery (DNR; neurocognitive disorder up to 30 days postoperative) and postoperative neurocognitive disorders (POCD; neurocognitive disorder 1-12 months postoperative) occur frequently after surgery, with diabetes mellitus (DM) suggested to contribute to this. This was a single-center prospective cohort study. The main aim of this study was to investigate the role of DM and preoperative hemoglobin A1c (HbA1c) in the development of POCDs after noncardiac surgery.

METHODS

Older adult patients ≥65 years of age scheduled for elective surgery were recruited. The Modified Telephone Interview for Cognitive Status questionnaire (TICS-M), a test of global cognitive functioning, was administered to determine cognition. Preoperative, 30-day postoperative, and 6-month postoperative cognition were compared for patients with and without DM. Cognitive decline was subdivided into mild (1 to 2 standard deviations below controls) and major (≥2 standard deviations below controls) DNR or POCD. Preoperative HbA1c levels were correlated with TICS-M scores.

RESULTS

We analyzed 102 patients [median (IQR [range]) age 72.0 (5 [68-74])]), who were divided into patients with DM (80 patients [78%]) and patients without DM (22 patients [22%]). Baseline cognitive function was similar for both groups. Repeated measures ANOVA showed that mean DM patient TICS-M scores decreased 30 days postoperative (F(2, 200) = 4.0, p = 0.02), with subsequent recovery 6-month postoperative, compared to stable TICS-M scores in non-DM patients. There were significantly more DM patients with DNR than non-DM patients (n = 11 [50%] vs. n = 14 [17.5%]; p = 0.031). There were no between-group differences in mild or major POCD. Higher preoperative HbA1c levels were significantly correlated with decreased 30-day Δcognition scores (F(1, 54) = 9.4, p = 0.003) with an R2 of 0.149 (β -0.45, 95% confidence interval: -0.735 to -0.154).

CONCLUSIONS

Older adult patients with DM undergoing surgery have an increased risk of DNR compared to older adult non-DM patients, but no increased risk of POCD. In DM patients, higher preoperative HbA1c levels were associated with an increased risk of DNR.

Type 1 and other types of diabetes mellitus in the perioperative period. What the anaesthetist should know

Diabetes mellitus is often treated as a uniform disease in the perioperative period. Type 2 diabetes is most commonly encountered, and only a minority of surgical patients have been diagnosed with another type of diabetes. Patients with a specific type of diabetes can be particularly prone to perioperative glycaemic dysregulation. In addition, certain type-related features and pitfalls should be taken into account in the operating theatre. In this narrative review, we discuss characteristics of types of diabetes other than type 2 diabetes relevant to the anaesthetist, based on available literature and data from our clinic.

Prospective comparison of three methods for detecting peri-operative neurocognitive disorders in older adults undergoing cardiac and non-cardiac surgery

Postoperative neurocognitive disorders occur frequently in older adult patients. Neuropsychological assessment is the gold standard for diagnosis, but the resources required for routine use are significant. Instead, it is common for simplified and unvalidated tests to be used for trials and in clinical practice. We undertook a single-centre prospective observational study in elective surgical patients aged ≥ 65 years recruited between September 2019 and January 2021. Patients underwent neuropsychological assessment, the Modified Telephone Interview for Cognitive Status and Montreal Cognitive Assessment before surgery. Tests were repeated at approximately four to eight postoperative weeks. We included 105 patients and 28 (27%) were lost to follow-up. Pre-operative Modified Telephone Interview for Cognitive Status and cognitive domain scores were very weakly to moderately correlated (r = 0.09-0.41). Pre-operative Montreal Cognitive Assessment and cognitive domain scores were very weakly to weakly correlated (r = 0.17-0.37) Postoperative Modified Telephone Interview for Cognitive Status and cognitive domain scores were very weakly to weakly correlated (r = 0.09-0.36). Postoperative Montreal Cognitive Assessment score and cognitive domain scores were very weakly to weakly correlated (r = 0.07-0.36). Overall, there was limited agreement between tests. We conclude that the Modified Telephone Interview for Cognitive Status and Montreal Cognitive Assessment should not be used in isolation to diagnose postoperative neurocognitive disorders. There seems to be little to no pre-operative, postoperative or pre- to postoperative correlation between these tests and the neuropsychological assessment in older adults without pre-operative cognitive impairment.

Patients with infective endocarditis undergoing cardiac surgery have distinct ROTEM profiles and more bleeding complications compared to patients without infective endocarditis

BACKGROUND

The coagulation system is crucial in the pathogenesis of infective endocarditis and undergoes significant changes during course of the disease. However, little is known about the implications of those changes in the perioperative period. Aim of the present study was to delineate the specific coagulation patterns and their clinical consequence in patients undergoing cardiac surgery due to infective endocarditis.

METHODS

In this single-centre, exploratory, prospective observational study, we investigated the incidence and degree of coagulopathy in patients with (n = 31) and without infective endocarditis (n = 39) undergoing cardiac valve surgery. The primary outcome was the differences between these two groups in rotational thromboelastometry (ROTEM) results before, during and after surgery. The secondary outcomes were the differences between the groups in heparin sensitivity, bleeding complications, and transfusion requirements.

RESULTS

Most ROTEM parameters in EXTEM, INTEM and FIBTEM assays were significantly altered in patients with infective endocarditis. Clotting time in the EXTEM assay was significantly prolonged in the endocarditis group at all time-points, while all clot firmness parameters (A5, A10 and MCF) were significantly increased. The heparin sensitivity index was significantly lower in the endocarditis group (median index 0.99 vs 1.17s. IU-1.kg-1, p = .008), indicating increased heparin resistance. Patients with infective endocarditis had more bleeding complications as assessed by the universal definition of perioperative bleeding score (OR 3.0, p = .018), and more patients with endocarditis underwent early re-exploration (p = .018).

CONCLUSIONS

The findings of this exploratory investigation show significantly altered coagulation profiles in patients with infective endocarditis, with concomitant hyper- and hypocoagulability. Furthermore, the incidence of bleeding complications and transfusion requirements were increased in patients with endocarditis. These results show the potential of ROTEM to detect coagulation abnormalities in patients with infective endocarditis. Existing point-of-care coagulation testing guided algorithms for optimizing perioperative coagulation management possibly need to be adjusted for these high-risk patients undergoing cardiac surgery.

Anesthetic considerations for endovascular treatment in stroke therapy

PURPOSE OF REVIEW

The introduction of clot removement by endovascular treatment (EVT) in 2015 has improved the clinical outcome of patients with acute ischemic stroke (AIS) due to a large vessel occlusion (LVO). Anesthetic strategies during EVT vary widely between hospitals, with some departments employing local anesthesia (LA), others performing conscious sedation (CS) or general anesthesia (GA). The optimal anesthetic strategy remains debated. This review will describe the effects of anesthetic strategy on clinical and radiological outcomes and hemodynamic parameters in patients with AIS undergoing EVT.

RECENT FINDINGS

Small single-center randomized controlled trails (RCTs) found either no difference or favored GA, while large observational cohort studies favored CS or LA. RCTs using LA as separate comparator arm are still lacking and a meta-analysis of observational studies failed to show differences in functional outcome between LA vs. other anesthetic strategies. Advantages of LA were shorter door-to-groin time in patients and less intraprocedural hypotension, which are both variables that are known to impact functional outcome.

SUMMARY

The optimal anesthetic approach in patients undergoing EVT for stroke therapy is still unclear, but based on logistics and peri-procedural hemodynamics, LA may be the optimal choice. Multicenter RCTs are warranted comparing LA, CS and GS with strict blood pressure targets and use of the same anesthetic agents to minimize confounding variables.

Elevated cerebrospinal fluid glucose levels and diabetes mellitus are associated with activation of the neurotoxic polyol pathway

AIMS/HYPOTHESIS

During hyperglycaemia, some glucose bypasses glycolysis and is metabolised via the potentially neurotoxic polyol pathway, in which glucose is metabolised to sorbitol and fructose. Increased polyol concentrations have been demonstrated in the cerebrospinal fluid (CSF) of neurological patients with and without diabetes mellitus. However, polyol levels in patients without evident neurological abnormalities have not been investigated so far. The aim of this study was to determine CSF polyol concentrations in patients without major neurological disease with normal or elevated CSF glucose concentrations.

METHODS

This observational cohort study used CSF and plasma analyses, as well as clinical data, from 30 participants of the Anaesthetic Biobank of Cerebrospinal Fluid study. Biomaterial was collected from adult patients scheduled for elective surgery under spinal anaesthesia. CSF polyol concentrations were measured by GC/flame ionisation detector in ten patients with normal CSF glucose levels (group 1), ten patients with elevated CSF glucose levels (group 2) and ten patients with elevated CSF glucose levels and type 2 diabetes (group 3). We compared the concentrations of plasma glucose, CSF glucose, sorbitol and fructose, and CSF polyol/glucose ratios between the three groups, and determined the correlation between plasma glucose levels and CSF glucose, sorbitol and fructose levels.

RESULTS

Groups 2 and 3 had significantly higher CSF fructose levels compared with group 1 (p=0.036 and p<0.001, respectively). Group 3 showed significant differences compared with groups 1 and 2 for CSF sorbitol (p<0.001 and 0.036, respectively). Moreover, patients with diabetes had a significantly higher CSF sorbitol/glucose ratio compared with patients without diabetes. There was a strong positive correlation between plasma glucose and CSF glucose, sorbitol and fructose. Finally, age, sex, CSF/plasma albumin ratio and preoperative cognitive function scores were significantly correlated with plasma glucose and CSF glucose, sorbitol and fructose levels.

CONCLUSIONS/INTERPRETATION

Hyperglycaemia causes a proportional increase in polyol concentrations in CSF of patients without major neurological disease. Furthermore, this study provides the first indication of upregulation of the cerebral polyol pathway in patients with diabetes without evident neurological abnormalities.

Amelioration of endothelial dysfunction by sodium glucose co-transporter 2 inhibitors: pieces of the puzzle explaining their cardiovascular protection

Sodium glucose co‐transporter 2 inhibitors (SGLT‐2is) improve cardiovascular outcomes in both diabetic and non‐diabetic patients. Preclinical studies suggest that SGLT‐2is directly affect endothelial function in a glucose‐independent manner. The effects of SGLT‐2is include decreased oxidative stress and inflammatory reactions in endothelial cells. Furthermore, SGLT2is restore endothelium‐related vasodilation and regulate angiogenesis. The favourable cardiovascular effects of SGLT‐2is could be mediated via a number of pathways: (1) inhibition of the overactive sodium‐hydrogen exchanger; (2) decreased expression of nicotinamide adenine dinucleotide phosphate oxidases; (3) alleviation of mitochondrial injury; (4) suppression of inflammation‐related signalling pathways (e.g., by affecting NF‐κB); (5) modulation of glycolysis; and (6) recovery of impaired NO bioavailability. This review focuses on the most recent progress and existing gaps in preclinical investigations concerning the direct effects of SGLT‐2is on endothelial dysfunction and the mechanisms underlying such effects.

Empagliflozin reduces oxidative stress through inhibition of the novel inflammation/NHE/[Na+]c/ROS-pathway in human endothelial cells

Inflammation causing oxidative stress in endothelial cells contributes to heart failure development. Sodium/glucose cotransporter 2 inhibitors (SGLT2i's) were shown to reduce heart failure hospitalization and oxidative stress. However, how inflammation causes oxidative stress in endothelial cells, and how SGLT2i's can reduce this is unknown. Here we hypothesized that 1) TNF-α activates the Na⁺/H⁺ exchanger (NHE) and raises cytoplasmatic Na⁺ ([Na⁺]_c), 2) increased [Na⁺]_c causes reactive oxygen species (ROS) production, and 3) empagliflozin (EMPA) reduces inflammation-induced ROS through NHE inhibition and lowering of [Na⁺]_c in human endothelial cells. Human umbilical vein endothelial cells (HUVECs) and human coronary artery endothelial cells (HCAECs) were incubated with vehicle (V), 10 ng/ml TNF-α, 1 µM EMPA or the NHE inhibitor Cariporide (CARI, 10 µM) and NHE activity, intracellular [Na⁺]_c and ROS were analyzed. TNF-α enhanced NHE activity in HCAECs and HUVECs by 92% (p < 0.01) and 51% (p < 0.05), respectively, and increased [Na⁺]_c from 8.2 ± 1.6 to 11.2 ± 0.1 mM (p < 0.05) in HCAECs. Increasing [Na⁺]_c by ouabain elevated ROS generation in both HCAECs and HUVECs. EMPA inhibited NHE activity in HCAECs and in HUVECs. EMPA concomitantly lowered [Na⁺]_c in both cell types. In both cell types, TNF α-induced ROS was lowered by EMPA or CARI, with no further ROS lowering by EMPA in the presence of CARI, indicating EMPA attenuated ROS through NHE inhibition. In conclusion, inflammation induces oxidative stress in human endothelial cells through NHE activation causing elevations in [Na⁺]_c, a process that is inhibited by EMPA through NHE inhibition.

Empagliflozin reduces TNFa-induced reactive oxygen species through inhibition of the human endothelial Na+/H+ exchanger 1

Background

Chronic low-grade inflammation, endothelial dysfunction and oxidative stress are major interactive pathways contributing to the pathogenesis of HFpEF. The sodium/glucose cotransporter 2 (SGLT2) inhibitor Empagliflozin (EMPA) inhibits inflammation-induced ROS generation in endothelial cells. EMPA also lowers Na+/H+ exchanger 1 (NHE1) activity and cytoplasmatic Na+ levels ([Na+]c) in cardiomyocytes.

Purpose

It is unknown how inflammation causes oxidative stress in endothelial cells and how EMPA can mitigate this. Here we examined for human endothelial cells whether 1) inflammatory mediators activate NHE1 activity, 2) increased [Na+]c mediates the inflammation-induced ROS production, and 3) EMPA reduces inflammation-induced ROS through NHE1 inhibition.

Methods

Human umbilical vein endothelial cells (HUVECs) and human coronary artery endothelial cells (HCAECs) were incubated with vehicle (V), 10ng/mL TNFα, 1μM EMPA or the canonical NHE1 inhibitor 10μM Cariporide. NHE1 activity was measured using the intracellular pH sensitive seminaphtharhodafluor fluorescence, by the pH recovery rate after an ammonium pulse. Intracellular ROS were detected by fluorescent live cell imaging in the presence of 10ng/mL TNFα or under increased Na+ conditions using 100nM ouabain (partial inhibition of the Na+/K+ pump). [Na+]c was measured using the sodium-binding benzofuran isophthalate 1 fluorescent probe.

Results

TNFα enhanced NHE1 activity in HCAECs (Fig a, in Δ[H+]/sec, V 0.81±0.14, TNFα 1.86±0.35 p&lt;0.05). Increasing [Na+]c by ouabain elevated ROS generation (Fig b, in mM, HUVECs; V 5.6±1.3, ouabain 25.2±1.6 p&lt;0.001, HCAECs; V 18.5±2.4, ouabain 91.2±32.6 p&lt;0.05). EMPA reduced NHE1 activity in HUVECs (in Δ[H+]/sec, V 3.55±0.54, EMPA 1.66±0.25 p&lt;0.01 vs V, Cariporide 0.95±0.11 p&lt;0.001 vs V). HCAECs showed similar results. EMPA lowered [Na+]c (HUVECs; from 8.8±0.9 to 6.0±0.5 mM, p&lt;0.05, HCAECs; from 7.8±0.7 to 4.0±0.8 mM, p&lt;0.001). ROS generation was reversed in the presence of EMPA and/or Cariporide indicating that the effect was mediated by NHE inhibition (Fig c).

Conclusions

TNFα induces oxidative stress in EC through NHE1 activation and the consequently increased [Na+]c. EMPA acutely inhibits TNFα-induced ROS generation by inhibiting NHE1 and lowering [Na+]c in human cardiac and non-cardiac endothelial cells. Our data suggest that the previously reported cardiac effects of EMPA on NHE1 and [Na+]c are also present in endothelial cells. Endothelial ion homeostasis may be a valuable target to reduce inflammation-induced ROS generation and can constitute the pathway through which SGLT2 inhibitors offer protection in HFpEF patients, as examined in the EMPEROR-Preserved trial.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Effects of surgery and general anaesthesia on sleep-wake timing: CLOCKS observational study

Surgery and general anaesthesia have the potential to disturb the body’s circadian timing system, which may affect postoperative outcomes. Animal studies suggest that anaesthesia could induce diurnal phase shifts, but clinical research is scarce. We hypothesised that surgery and general anaesthesia would result in peri‐operative changes in diurnal sleep–wake patterns in patients. In this single‐centre prospective cohort study, we recruited patients aged ≥18 years scheduled for elective surgery receiving ≥30 min of general anaesthesia. The Munich Chronotype Questionnaire and Pittsburgh Sleep Quality Index were used to determine baseline chronotype, sleep characteristics and sleep quality. Peri‐operative sleeping patterns were logged. Ninety‐four patients with a mean (SD) age of 52 (17) years were included; 56 (60%) were female. The midpoint of sleep (SD) three nights before surgery was 03.33 (55 min) and showed a phase advance of 40 minutes to 02.53 (67 min) the night after surgery (p < 0.001). This correlated with the midpoint of sleep three nights before surgery and was not associated with age, sex, duration of general anaesthesia or intra‐operative dexamethasone use. Peri‐operatively, patients had lower subjective sleep quality and worse sleep efficiency. Disruption started from one night before surgery and did not normalise until 6 days after surgery. We conclude that there is a peri‐operative phase advance in midpoint of sleep, confirming our hypothesis that surgery and general anaesthesia disturb the circadian timing system. Patients had decreased subjective sleep quality, worse sleep efficiency and increased daytime fatigue.

Sodium Glucose Co-Transporter 2 Inhibitors Ameliorate Endothelium Barrier Dysfunction Induced by Cyclic Stretch through Inhibition of Reactive Oxygen Species

SGLT-2i's exert direct anti-inflammatory and anti-oxidative effects on resting endothelial cells. However, endothelial cells are constantly exposed to mechanical forces such as cyclic stretch. Enhanced stretch increases the production of reactive oxygen species (ROS) and thereby impairs endothelial barrier function. We hypothesized that the SGLT-2i's empagliflozin (EMPA), dapagliflozin (DAPA) and canagliflozin (CANA) exert an anti-oxidative effect and alleviate cyclic stretch-induced endothelial permeability in human coronary artery endothelial cells (HCAECs). HCAECs were pre-incubated with one of the SGLT-2i's (1 µM EMPA, 1 µM DAPA and 3 µM CANA) for 2 h, followed by 10% stretch for 24 h. HCAECs exposed to 5% stretch were considered as control. Involvement of ROS was measured using N-acetyl-l-cysteine (NAC). The sodium-hydrogen exchanger 1 (NHE1) and NADPH oxidases (NOXs) were inhibited by cariporide, or GKT136901, respectively. Cell permeability and ROS were investigated by fluorescence intensity imaging. Cell permeability and ROS production were increased by 10% stretch; EMPA, DAPA and CANA decreased this effect significantly. Cariporide and GKT136901 inhibited stretch-induced ROS production but neither of them further reduced ROS production when combined with EMPA. SGLT-2i's improve the barrier dysfunction of HCAECs under enhanced stretch and this effect might be mediated through scavenging of ROS. Anti-oxidative effect of SGLT-2i's might be partially mediated by inhibition of NHE1 and NOXs.

Effects of Hyperglycemia and Diabetes Mellitus on Coagulation and Hemostasis

In patients with diabetes, metabolic disorders disturb the physiological balance of coagulation and fibrinolysis, leading to a prothrombotic state characterized by platelet hypersensitivity, coagulation disorders and hypofibrinolysis. Hyperglycemia and insulin resistance cause changes in platelet number and activation, as well as qualitative and/or quantitative modifications of coagulatory and fibrinolytic factors, resulting in the formation of fibrinolysis-resistant clots in patients with diabetes. Other coexisting factors like hypoglycemia, obesity and dyslipidemia also contribute to coagulation disorders in patients with diabetes. Management of the prothrombotic state includes antiplatelet and anticoagulation therapies for diabetes patients with either a history of cardiovascular disease or prone to a higher risk of thrombus generation, but current guidelines lack recommendations on the optimal antithrombotic treatment for these patients. Metabolic optimizations like glucose control, lipid-lowering, and weight loss also improve coagulation disorders of diabetes patients. Intriguing, glucose-lowering drugs, especially cardiovascular beneficial agents, such as glucagon-like peptide-1 receptor agonists and sodium glucose co-transporter inhibitors, have been shown to exert direct anticoagulation effects in patients with diabetes. This review focuses on the most recent progress in the development and management of diabetes related prothrombotic state.

The role of intraoperative hypotension on the development of postoperative cognitive dysfunction: a systematic review

STUDY OBJECTIVE

To clarify whether intraoperative hypotension contributes to the development of postoperative cognitive dysfunction.

DESIGN

A systematic review of prospective studies reporting on intraoperative hypotension and postoperative cognitive dysfunction in elective, non-cognitive impaired, adult surgical patients. PubMed, EMBASE and the Cochrane Library were searched up to the 1st of January 2021.

SETTING

Studies had to use a clear definition of hypotension, although differing definitions were accepted. Neurocognitive tests to determine postoperative cognitive dysfunction had to be done pre- and postoperatively, with a minimum follow-up of seven days postoperatively.

MEASUREMENTS

Risk of bias was assessed using the Cochrane Risk of Bias Tool 2.0 for randomized controlled trials and the Newcastle-Ottawa Scale for cohort studies.

MAIN RESULTS

Out of 941 studies screened, five randomized controlled trials and four cohort studies were included for qualitative analysis. Extensive methodological differences between studies were present hindering proper quantitive analysis. No studies reported statistically significant differences in incidence of postoperative cognitive dysfunction in hypo- compared to normotensive patients. Five studies reported exact incidences of postoperative cognitive dysfunction.

CONCLUSIONS

This systematic review showed no conclusive association between intraoperative hypotension and the development of postoperative cognitive dysfunction. Given the vast methodological differences of the included studies, the role of intraoperative hypotension in the development of postoperative cognitive dysfunction remains uncertain. Future research into the association between intraoperative hypotension and postoperative cognitive dysfunction should be conducted in a standardized manner.

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.

[Postoperative remote monitoring]

During the course of surgical interventions, complications mostly occur in the postoperative period. Slight clinical indications can be observed, which precede a significant deterioration of the patient's condition. On the general ward vital parameters, such as heart and breathing frequencies are measured every 4-8 h. Even if the monitoring of critically ill patients is increased to every 2 h and the measurement of vital functions takes 10 min, the patient is only monitored for 120 min in a 24 h period and remains postoperatively on the general ward without monitoring for 22 out of 24 h. New wireless monitoring systems are available to continuously register some vital functions with the aid of wearable sensors. These systems can alert and alarm ward personnel if the patient's condition deteriorates. Although the optimal monitoring system does not yet exist and implementation of these new wireless monitoring systems might involve some risks, these new methods offer a great opportunity to optimize surveillance of postoperative patients on the general ward.

Ventilation practices in burn patients—an international prospective observational cohort study

Background

It is unknown whether lung-protective ventilation is applied in burn patients and whether they benefit from it. This study aimed to determine ventilation practices in burn intensive care units (ICUs) and investigate the association between lung-protective ventilation and the number of ventilator-free days and alive at day 28 (VFD-28).

Methods

This is an international prospective observational cohort study including adult burn patients requiring mechanical ventilation. Low tidal volume (VT) was defined as VT ≤ 8 mL/kg predicted body weight (PBW). Levels of positive end-expiratory pressure (PEEP) and maximum airway pressures were collected. The association between VT and VFD-28 was analyzed using a competing risk model. Ventilation settings were presented for all patients, focusing on the first day of ventilation. We also compared ventilation settings between patients with and without inhalation trauma.

Results

A total of 160 patients from 28 ICUs in 16 countries were included. Low VT was used in 74% of patients, median VT size was 7.3 [interquartile range (IQR) 6.2–8.3] mL/kg PBW and did not differ between patients with and without inhalation trauma (p = 0.58). Median VFD-28 was 17 (IQR 0–26), without a difference between ventilation with low or high VT (p = 0.98). All patients were ventilated with PEEP levels ≥5 cmH2O; 80% of patients had maximum airway pressures &lt;30 cmH2O.

Conclusion

In this international cohort study we found that lung-protective ventilation is used in the majority of burn patients, irrespective of the presence of inhalation trauma. Use of low VT was not associated with a reduction in VFD-28.

Trial registration

Clinicaltrials.gov NCT02312869. Date of registration: 9 December 2014.

Second Update for Anaesthetists on Clinical Features of COVID-19 Patients and Relevant Management

The COVID-19 pandemic poses great challenges for healthcare workers around the world, including perioperative specialists. Previously, we provided a first overview of available literature on SARS-CoV-2 and COVID-19, relevant for anaesthetists and intensivists. In the current review, we provide an update of this topic, after a literature search current through May 2020. We discuss the evidence on perioperative risk for COVID-19 patients presenting for surgery, the risk of transmission of SARS-CoV-2 in the operating room, and the current literature on laboratory diagnostics. Furthermore, cardiovascular and nervous system involvement in COVID-19 are discussed, as well as considerations in diabetic patients. Lastly, the latest evidence on pharmacological treatment is summarised.

Registration of attentional function as a predictor of incident delirium (the RAPID study)

INTRODUCTION

Older adults undergoing elective surgery have a high risk of developing postoperative delirium (POD). Validated models predicting POD are scarce. This study investigated whether preoperative impairment of attentional function predicts POD in older adults without previously diagnosed cognitive impairment.

METHODS

In this prospective cohort study we recruited patients aged ≥70 years preceding major elective surgery. Preoperatively a visual vigilance test was administered to determine intra-individual reaction-time variability. Postoperatively, presence of delirium was screened daily.

RESULTS

We recruited 152 patients, 25 (16.4%) developed POD. Intra-individual reaction-time variability was not significantly different between patients with or without POD (0.18 ± 0.08 ms vs 0.22 ± 0.11 ms; P = 0.087). Receiver operating characteristic analyses indicated a poor accuracy for POD (area under the curve 0.609 ± 0.63). Except for surgery duration, no clinically significant between-group differences were found for secondary outcome parameters.

DISCUSSION

Preoperative intra-individual reaction time variability does not predict the incidence of POD in older patients undergoing major elective surgery.

Update for Anaesthetists on Clinical Features of COVID-19 Patients and Relevant Management

When preparing for the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the coronavirus infection disease (COVID-19) questions arose regarding various aspects concerning the anaesthetist. When reviewing the literature it became obvious that keeping up-to-date with all relevant publications is almost impossible. We searched for and summarised clinically relevant topics that could help making clinical decisions. This is a subjective analysis of literature concerning specific topics raised in our daily practice (e.g., clinical features of COVID-19 patients; ventilation of the critically ill COVID-19 patient; diagnostic of infection with SARS-CoV-2; stability of the virus; Covid-19 in specific patient populations, e.g., paediatrics, immunosuppressed patients, patients with hypertension, diabetes mellitus, kidney or liver disease; co-medication with non-steroidal anti-inflammatory drugs (NSAIDs); antiviral treatment) and we believe that these answers help colleagues in clinical decision-making. With ongoing treatment of severely ill COVID-19 patients other questions will come up. While respective guidelines on these topics will serve clinicians in clinical practice, regularly updating all guidelines concerning COVID-19 will be a necessary, although challenging task in the upcoming weeks and months. All recommendations during the current extremely rapid development of knowledge must be evaluated on a daily basis, as suggestions made today may be out-dated with the new evidence available tomorrow.

Perioperative approach of allergic patients

Perioperative allergic reactions are rare, yet important complications of anesthesia. Severe, generalized allergic reactions called anaphylaxis are estimated to have a mortality of 3.5-4.8%. Adequate recognition and handling of a severe perioperative anaphylactic reaction result in better outcomes, including less hypoxic-ischemic encephalopathy and death. The diagnosis of a perioperative allergic reaction can be difficult as the list of possible culprits of a perioperative allergic reaction is extensive. Making an informed guess on the causative agent and avoiding this agent in future anesthesia procedures is undesirable and unsafe. Therefore, to ensure future patient safety, a thorough investigation following a perioperative allergic reaction is mandatory. A collaborate approach by allergists and anesthesiologists is advised. In this article, we discuss the basic approach of the allergic patient and of patients with a suspected allergy to perioperatively administered medication.

Liraglutide for perioperative management of hyperglycaemia in cardiac surgery patients: a multicentre randomized superiority trial

AIMS

Most cardiac surgery patients, with or without diabetes, develop perioperative hyperglycaemia, for which intravenous insulin is the only therapeutic option. This is labour-intensive and carries a risk of hypoglycaemia. We hypothesized that preoperative administration of the glucagon-like peptide-1 receptor agonist liraglutide reduces the number of patients requiring insulin for glycaemic control during cardiac surgery.

MATERIALS AND METHODS

In this randomized, blinded, placebo-controlled, parallel-group, balanced (1:1), multicentre randomized, superiority trial, adult patients undergoing cardiac surgery in four Dutch tertiary hospitals were randomized to receive 0.6 mg subcutaneous liraglutide on the evening before surgery and 1.2 mg after induction of anaesthesia or matching placebo. Blood glucose was measured hourly and controlled using an insulin-bolus algorithm. The primary outcome was insulin administration for blood glucose >8.0 mmol/L in the operating theatre. Research pharmacists used centralized, stratified, variable-block, randomization software. Patients, care providers and study personnel were blinded to treatment allocation.

RESULTS

Between June 2017 and August 2018, 278 patients were randomized to liraglutide (139) or placebo (139). All patients receiving at least one study drug injection were included in the intention-to-treat analyses (129 in the liraglutide group, 132 in the placebo group). In the liraglutide group, 55 (43%) patients required additional insulin compared with 80 (61%) in the placebo group and absolute difference 18% (95% confidence interval 5.9-30.0, P = 0.003). Dose and number of insulin injections and mean blood glucose were all significantly lower in the liraglutide group. We observed no difference in the incidence of hypoglycaemia, nausea and vomiting, mortality or postoperative complications.

CONCLUSIONS

Preoperative liraglutide, compared with placebo, reduces insulin requirements while improving perioperative glycaemic control during cardiac surgery.

Effect of electroacupuncture on sedation requirements during colonoscopy: a prospective placebo-controlled randomised trial

INTRODUCTION

Propofol provides excellent sedation during colonoscopy. However, its application, namely when used together with an opioid, is associated with cardiopulmonary depression. Acupuncture is used nowadays for the treatment of pain and anxiety, and also to induce sedation. We hypothesised that electroacupuncture (EA) during colonoscopy would have sedative effects, thereby reducing propofol requirements to achieve an adequate level of sedation.

METHOD

The study was designed and conducted as a single centre, patient and observer blinded, sham- and placebo-controlled randomised trial. Patients scheduled for elective colonoscopy under deep propofol/alfentanil sedation were randomly assigned to receive unilateral EA, sham-acupuncture (SA) or placebo-acupuncture (PA) at ST36, PC6 and LI4. The primary outcome parameter was the total dosage of propofol. Secondary outcomes included the patients' and endoscopists' satisfaction levels evaluated by questionnaires.

RESULTS

The dosage of propofol required (median [IQR]) was not significantly different between the three groups (EA group 147 μg/kg/min [109-193] vs SA group 141 μg/kg/min [123- 180] vs PA group 141 μg/kg/min [112-182]; P=0.776). There was also no significant difference in alfentanil consumption (P=0.634). Global satisfaction (median [IQR]) among patients (EA group 6.6 [6.0-7.0] vs SA group 6.8 [6.0-7.0] vs PA group 6.5 [6.0-7.0]; P=0.481) and endoscopists (6.0 [5.0-6.0] for all groups; P=0.773) did not significantly differ between the three groups. There was no significant difference in the number of cardiorespiratory events.

CONCLUSION

For colonoscopy, the applied mode of EA did not show any propofol-sparing sedative effect compared with sham or placebo acupuncture.

TRIAL REGISTRATION

The trial is registered in the Netherland's Trial Registry (NTR4325).

Effect of Cognitive Aids on Adherence to Best Practice in the Treatment of Deteriorating Surgical Patients: A Randomized Clinical Trial in a Simulation Setting

Importance

Failure to rescue causes significant morbidity and mortality in the surgical population. Human error is often the underlying cause of failure to rescue. Human error can be reduced by the use of cognitive aids.

Objectives

To test the effectiveness of cognitive aids on adherence to best practice in the management of deteriorating postoperative surgical ward patients.

Design, Setting, and Participants

Randomized clinical trial in a simulation setting. Surgical teams consisted of 1 surgeon and 2 nurses from a surgical ward from 4 different hospitals in Amsterdam, the Netherlands. Data were analyzed between February 2, 2017, and December 18, 2018.

Interventions

The teams were randomized to manage 3 simulated deteriorating patient scenarios with or without the use of cognitive aids.

Main Outcomes and Measures

The primary outcome of the study was failure to adhere to best practice, expressed as the percentage of omitted critical management steps. The secondary outcome of the study was the perceived usability of the cognitive aids.

Results

Of the total participants, 93 were women and 51 were men. Twenty-five surgical teams performed 75 patient scenarios with cognitive aids, and 25 teams performed 75 patient scenarios without cognitive aids. Using the cognitive aids resulted in a reduction of omitted critical management steps from 33% to 10%, which is a 70% (P < .001) reduction. This effect remained significant (odds ratio, 0.63; 95% CI, -0.228 to -0.061; P = .001) in a multivariate analysis. Overall usability (scale of 0-10) of the cognitive aids was scored at a median of 8.7 (interquartile range, 8-9).

Conclusions and Relevance

Failure to comply with best practice management of postoperative complications is associated with worse outcomes. In this simulation study, adherence to best practice in the management of postoperative complications improves significantly by the use of cognitive aids. Cognitive aids for deteriorating surgical patients therefore have the potential to reduce failure to rescue and improve patient outcome.

Trial Registration

ClinicalTrials.gov identifier: NCT03812861.

Remote wireless vital signs monitoring on the ward for early detection of deteriorating patients: A case series

INTRODUCTION

Remote wireless monitoring is a new technology that allows the continuous recording of ward patients' vital signs, supporting nurses by measuring vital signs frequently and accurately. A case series is presented to illustrate how these systems might contribute to improved patient surveillance.

METHODS AND RESULTS

Five hospitals in three European countries installed a remote wireless vital signs monitoring system on medical or surgical wards. Heart rate, respiratory rate and temperature were measured by the system every 2 min. Four cases of (paroxysmal) atrial fibrillation are presented, two cases of sepsis and one case each of pyrexia, cardiogenic pulmonary edema and pulmonary embolisms. All cases show that the remote monitoring system revealed the first signs of ventilatory and circulatory deterioration before a change in the trends of the respective values became obvious by manual vital signs measurement.

DISCUSSION

This case series illustrates that a wireless remote vital signs monitoring system on medical and surgical wards has the potential to reduce time to detect deteriorating patients.