Inflammation and Oxidative Stress in the Context of Extracorporeal Cardiac and Pulmonary Support

Effect of extracorporeal circulation on structure of main components of animal plasma - ATR-IR and 2D-COS studies: Part I

Every year, more and more adults and children with severe cardiac and/or respiratory failure require connection to extracorporeal circulation (ECC). Despite a life-saving role in emergency settings, the use of ECC is associated with several serious complications, which result from structural changes in the plasma components. As yet, the molecular mechanism of these changes was not well recognized, and therefore we undertook the first spectroscopic study of structural changes in plasma during ECC. Vibrational spectroscopy coupled with two-dimensional correlation spectroscopy (2D-COS) is a powerful tool for elucidation of variations at a molecular level. The spectra of animal plasma were recorded by ATR-IR (Attenuated Total Reflection-Infrared) technique, which enables measurements of strongly absorbing samples in a non-destructive way. Moving-window and 2D-COS methods were used to obtain more detailed information about the correlation between spectral features and vibrations of functional groups. A comprehensive analysis of variations in the main plasma components requires using bands from both polar (NH, OH, CO, and CO) and non-polar groups (aliphatic and aromatic moieties). Of particular interest is the effect of the state of water on the structure and intermolecular interactions of the plasma under ECC.

Microaxial pump-supported coronary surgery without CPB to optimize outcome in severely impaired left ventricles

AIMS

Cardiopulmonary bypass (CPB) is the standard approach for coronary artery bypass grafting (CABG) in advanced ischaemic cardiomyopathy. Microaxial pump support has been envisioned to allow for beating-heart CABG without CPB (MPCAB), thereby avoiding CPB-inherent complications. This study aims to compare the in-hospital and follow-up outcome of MPCAB versus CPB-CABG in patients with severely impaired left ventricular function.

METHODS AND RESULTS

Eleven patients suffering from three-vessel coronary artery disease with median ejection fraction of 27% and deemed appropriate for CABG according to a heart team decision underwent MPCAB (support up to 5.5 L/min). Propensity score matching generated a CPB-CABG control group (n = 33). The primary endpoint was defined as death from any cause by the end of the follow-up (up to 4 years). MPCAB enabled continuous intraoperative and postoperative haemodynamic stabilization and complete myocardial revascularization. After CPB-CABG, additional mechanical circulatory support was required in 45.5% (vs. 9.1% in MPCAB; P = 0.0363). The follow-up all-cause mortality after MPCAB amounted to 0% (vs. 33.3% after CPB-CABG; P = 0.0414; NNT = 3). MPCAB patients showed a significantly decreased occurrence of major adverse cardiovascular events (MACE: 0% vs. 39.4%; P = 0.0189).

CONCLUSIONS

MPCAB allows for complete surgical revascularization without the necessity of extracorporeal circulation in spite of severely impaired left ventricular function. This first comparative study on the outcome after MPCAB versus CPB-CABG demonstrates a significantly decreased risk of death as well as MACE in MPCAB patients. The MPCAB concept expands the spectrum of patients eligible for CABG without CPB towards patients with severely impaired left ventricular function.

Can we reduce the risk of neurological injury in critically ill children on initiation of ECLS? A narrative review of potential modifiable factors

Neurological morbidity and mortality remain high in children requiring extracorporeal membrane oxygenation (ECMO). Although the severity of illness at the time of ECMO initiation and the nature of the underlying disease are strongly linked to the development of acute brain injury, several important factors are associated with neurological complications during ECMO support. Many of these factors, particularly those encountered during the early phase of ECMO initiation (first 24 hours), may be modifiable and represent potential targets for interventional studies aiming for improvement of neurological outcomes in pediatric ECMO patients. In this review from the European Extracorporeal Life Support Organization (EuroELSO) Working Group on Neurologic Monitoring and Outcome, we aim to summarize current knowledge on modifiable factors associated with brain injury during ECMO and their potential impact on outcome.

Impact of enteral nutrition initiated within 24 h of ECMO on nutritional status and inflammatory response in children

Objective

Malnutrition remains a significant issue in children undergoing ECMO. This study aimed to investigate the effects of initiating enteral nutrition (EN) within 24 h on the adequacy of nutrient intake, nutritional status, anabolic metabolism, and inflammatory markers in children receiving ECMO.

Methods

This was a prospective observational cohort study, including children receiving ECMO therapy at the Children's Hospital of Chongqing Medical University of China from April 2018 to August 2024. Patients were divided into early EN (EEN) and late EN (LEN) groups based on whether effective EN was initiated within 24 h after the start of ECMO. T-tests or Mann-Whitney U and Chi-square tests were used to compare the clinical characteristics, serum total protein (TP), nutritional intake, serum cholinesterase (CHE), and C-reactive protein (CRP) levels between the two groups. Linear mixed-effects models (LME) were applied to assess the effect of EEN on changes in CRP and CHE levels over time during ECMO.

Results

A total of 47 children were included in this study, with 24 patients (51.1%) successfully receiving EEN. The PRISM3 score was higher in the LEN group (P = 0.016). The majority of children in the EEN group had pneumonia or ARDS (P < 0.001). The average daily energy and protein intake, as well as their adequacy, was higher in the EEN group compared to the LEN group (P < 0.001), although the EEN group experienced more frequent interruptions in EN (P < 0.05). Serum TP levels in the EEN group were higher than those in the LEN group during the first 3 days of ECMO (P < 0.05). The median CHE levels were higher, and the median CRP levels were lower in the EEN group compared to the LEN group (P < 0.05). LME analysis showed a significant interaction effect between EEN and time on CRP and CHE levels (P < 0.001).

Conclusion

Successfully initiating EN within 24 h significantly improves the nutritional status of children receiving ECMO, promotes hepatic anabolic metabolism, and reduces inflammatory responses. This study provided new insights and data support for nutritional therapy strategies in children on ECMO.

Association between hyperlipidemia and postoperative delirium risk: a systematic review and meta-analysis

Introduction

The association between hyperlipidemia and its potential role as a risk factor for postoperative delirium (POD) remains unclear.

Methods

We systematically searched PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov to identify studies meeting the inclusion criteria. Outcomes of interest included comparisons of blood lipid levels between POD and non-POD (NPOD) patients, the association between hyperlipidemia and POD risk, and the predictive value of hyperlipidemia for POD.

Results

A total of nine studies involving 4,686 patients were included in the meta-analysis. Pooled analysis revealed that hyperlipidemia was significantly associated with an increased risk of POD (OR = 1.47; 95% CI 1.13-1.91; P = 0.004;) compared to patients without hyperlipidemia. Patients with POD exhibited significantly higher levels of total cholesterol (TC) (weighted mean difference [WMD] = 0.31; 95% CI 0.03-0.59; P = 0.030), triglycerides (TG) (WMD = 0.37; 95% CI 0.03-0.71; P = 0.033), and low-density lipoprotein cholesterol (LDL-C) (WMD = 0.09; 95% CI 0.01-0.17; P = 0.023) compared to NPOD patients. In contrast, high-density lipoprotein cholesterol (HDL-C) levels were significantly lower in POD patients (WMD = -0.07; 95% CI -0.12 to -0.01; P = 0.026). Insufficient evidence was available to summarize the area under the curve (AUC) results.

Conclusions

Blood lipid levels were significantly elevated in POD patients compared to NPOD patients. Hyperlipidemia was significantly associated with an increased risk of POD, highlighting its potential role as a risk factor.

Spatiotemporal metabolic mapping of ex-situ preserved hearts subjected to dialysis by integration of bio-SPME sampling with non-targeted metabolipidomic profiling

BACKGROUND

Normothermic ex situ heart perfusion (ESHP) has emerged as a valid modality for advanced cardiac allograft preservation and conditioning prior to transplantation though myocardial function declines gradually during ESHP thus limiting its potential for expanding the donor pool. Recently, the utilization of dialysis has been shown to preserve myocardial and coronary vasomotor function. Herein, we sought to determine the changes in myocardial metabolism that could support this improvement.

RESULTS

Male Yorkshire porcine hearts were subjected to ESHP for 8 h with or without dialysis. Alterations in metabolism were studied with an innovative in vivo solid-phase microextraction (SPME) technology coupled with global metabolite profiling at 15 min, 1.5, 4, and 8 h of perfusion. Bio-SPME sampling was performed by inserting SPME fibres coated with a PAN-based extraction phase containing mixed-mode (C8+benzenesulfonic acid) functionalities into the myocardium to a depth of their entire 8 mm coating or immersing them in the perfusate, followed by a 20-min extraction period for the analytes of interest. Dialyzed hearts demonstrated improved bioenergetics as evidenced by accelerated purine metabolism and less pronounced accumulation of intermediates of fatty acid β/ω-oxidation. Metabolic waste accumulation such as pro-inflammatory lipid mediators (e.g., leukotrienes) was mitigated thereby supporting the process of resolution of inflammation through excretion of specialized pro-resolving mediators (resolvins D1/D2, E2, protecin D1).

SIGNIFICANCE

Through implementing the unique analytical pipeline we demonstrated that the addition of dialysis may preserve cardiac metabolism allowing for prolonged ESHP. This strategy has the potential to facilitate high-risk donor organs' reconditioning prior to transplantation.

Early Prone Positioning As a Rescue Therapy for Moderate-to-severe Primary Graft Dysfunction After Bilateral Lung Transplant

OBJECTIVES

Primary graft dysfunction (PGD) affects survival after lung transplant (LT). The current hypothesis was that prone positioning (PP), proposed as a rescue maneuver to treat refractory hypoxemia due to PGD, may improve LT outcomes, especially when applied early.

DESIGN

Bilateral LT recipients developing moderate-to-severe PGD within 24 hours from intensive care unit admission were enrolled. From January 2020 to November 2021, patients developing PGD after LT were turned prone between 24 and 48 hours after diagnosis, only in case of radiological or oxygenation worsening ("late PP" group). After November 2021, patients were routinely turned prone within 24 hours from PGD diagnosis ("early PP"). A propensity score-weighted analysis, adjusted for clinically relevant covariates, was applied.

SETTING

Intensive care unit.

PARTICIPANTS

Bilateral LT recipients.

INTERVENTIONS

Early PP, late PP, or supine position.

MEASUREMENTS AND MAIN RESULTS

130 LT patients were screened and 67 were enrolled. A total of 25 (37%) recipients were treated in the supine position, 24 (36%) in early PP, and 18 (27%) in late PP. After propensity score weighting, both supine treatment (estimated effect for 1 ventilator-free day = 8.23, standard error: 2.97, p = 0.007) and early PP treatment (estimated effect = 9.42, standard error: 2.59, p < 0.001) were associated with greater 28-day ventilator-free days than late PP treatment (reference). Compared with late PP, early PP was also associated with better oxygenation, driving pressure, and static respiratory system compliance. Compared with supine recipients, the early PP group showed better oxygenation at 72 hours after PGD diagnosis.

CONCLUSIONS

Early PP in LT recipients with moderate-to-severe PGD seems to be associated with better 28-day ventilator-free days, oxygenation, and driving pressure than late PP.

Novel Insights in Perioperative Neuroprotection in Neonatal Congenital Heart Disease

Congenital heart disease (CHD) includes defects of intrauterine cardiac development that result in alterations to the morphology and/or physiology of the heart, usually expressed early in fetal or postnatal life. This group represents one of the most common congenital anomalies of all living newborns worldwide. Neurodevelopmental deficits are a reality in patients with CHDs and may contribute to significant sequela and long-term morbidity beginning in infancy and extending into adulthood. There is general agreement that the perioperative period of neonatal cardiac surgery may be responsible for a significant burden of lifelong neurological injury in patients with CHDs. Recent research has advanced understanding of neurodevelopmental trajectories, factors that increase neurodevelopmental risk, and neuroprotective strategies for patients with these disorders. In the present study, we aim to describe the different emerging strategies for neuroprotection in the perioperative period in neonatal patients with congenital heart disease.

To Hemoadsorb or Not to Hemoadsorb-Do We Have the Answer Yet? An Updated Meta-Analysis on the Use of CytoSorb in Sepsis and Septic Shock

Severe inflammation leading to organ dysfunction is the cornerstone of the pathophysiology of sepsis. Thus, from a theoretical point of view, rebalancing inflammation has the potential to improve patient outcomes.

METHODS

To better understand the clinical effectiveness of hemoadsorption in managing inflammation, we conducted an updated meta-analysis on the effects of CytoSorb in critically ill septic patients. Ten studies containing 715 patients (355 in the interventional group and 360 in the control group) have been included in the final analysis.

RESULTS

Statistical analysis demonstrated that the use of CytoSorb did not influence overall mortality (OR 0.95, 95% CI [0.58, 1.56], p = 0.85), but we observed a decreased mortality when comparing CytoSorb-treated patients with patients in the control group treated with continuous renal replacement therapy (CRRT) (OR 0.97, 95% CI [0.46, 0.98], p = 0.04). We also observed an increased mortality in patients in whom hemoadsorption was initiated earlier in the treatment course (OR 0.97, 95% CI [0.46, 0.98], p = 0.04). We did not observe any significant difference in either intensive care unit length of stay (p = 0.93) or between end-of-treatment severity scores in the two groups (p = 0.24).

CONCLUSIONS

Although it has a high risk of bias, current evidence does not support the routine use of CytoSorb in critically ill septic patients. The addition of CytoSorb to CRRT may be associated with decreased survival as compared to CRRT alone, but future studies are needed to draw a definitive conclusion.

Mixed Cardiogenic-Vasodilatory Shock: Current Insights and Future Directions

This state-of-the-art review describes the potential etiologies, pathophysiology, and management of mixed shock in the context of a proposed novel classification system. Cardiogenic-vasodilatory shock occurs when cardiogenic shock is complicated by inappropriate vasodilation, impairing compensatory mechanisms, and contributing to worsening shock. Vasodilatory-cardiogenic shock occurs when vasodilatory shock is complicated by myocardial dysfunction, resulting in low cardiac output. Primary mixed shock occurs when a systemic insult triggers both myocardial dysfunction and vasoplegia. Regardless of the etiology of mixed shock, the hemodynamic profile can be similar, and outcomes tend to be poor. Identification and treatment of both the initial and complicating disease processes is essential along with invasive hemodynamic monitoring given the evolving nature of mixed shock states. Hemodynamic support typically involves a combination of inotropes and vasopressors, with few data available to guide the use of mechanical circulatory support. Consensus definitions and novel treatment strategies are needed for this dangerous condition.

Alterations in novel inflammatory biomarkers during perioperative cardiovascular surgeries involving cardiopulmonary bypass: a retrospective propensity score matching study

Background

Cardiopulmonary bypass (CPB) triggers a strong inflammatory response in cardiovascular surgery patients during the perioperative period. This article mainly focuses on the perioperative application of novel inflammatory biomarkers in cardiovascular surgeries involving CPB.

Methods

Patients were divided into a CPB group and a non-CPB group according to whether they underwent CPB during cardiovascular surgery. Novel inflammatory biomarkers and clinical results were recorded. The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), platelet × neutrophil/lymphocyte ratio (SII), and monocyte × platelet × neutrophil/lymphocyte ratio (PIV) were calculated. The primary outcomes were perioperative prognosis between the CPB and non-CPB groups. The secondary outcomes included perioperative alterations of novel inflammatory biomarkers in the CPB group and predictive values of novel inflammatory biomarkers for postoperative infection and acute kidney injury.

Results

A total of 332 patients were initially included in the study. Before propensity score matching (PSM), there were 96 patients in the CPB group and 236 patients in the non-CPB group. After PSM, both groups included 58 patients each. Compared with the non-CPB group, the CPB group had a higher proportion of intraoperative transfusion of blood products (63.79% vs. 6.90%, P < 0.001), specifically for red blood cells (58.62% vs. 3.45%, P < 0.001) and plasma (41.38% vs. 1.72, P < 0.001), exhibited a higher drainage fluid volume within 24 h [380 (200-550) ml vs. 200 (24-330) ml, P = 0.002], and required longer durations of mechanical ventilation [14.3 (6.6-21.3) h vs. 5.75 (4.08-10.1) h, P < 0.001] and ICU stay [48.78 (44.92-89.38) h vs. 27.16 (21.67-46.25) h, P < 0.001]. After surgery, NLR [14.00 (9.93-23.08) vs. 11.55 (7.38-17.38), P = 0.043] was higher in the CPB group, while the PIV, PLR, and SII in the CPB group were lower than those in the non-CPB group on the first day after surgery.

Conclusions

Cardiovascular surgeries involving CPB exhibit a poorer prognosis compared to non-CPB procedures. Novel inflammatory biomarkers, including PLR, PIV, and SII, may offer valuable insights into the degree of postoperative inflammation, with NLR emerging as a potentially reliable prognostic indicator.

Neutrophils: a key component in ECMO-related acute organ injury

Extracorporeal membrane oxygenation (ECMO), as an extracorporeal life support technique, can save the lives of reversible critically ill patients when conventional treatments fail. However, ECMO-related acute organ injury is a common complication that increases the risk of death in critically ill patients, including acute kidney injury, acute brain injury, acute lung injury, and so on. In ECMO supported patients, an increasing number of studies have shown that activation of the inflammatory response plays an important role in the development of acute organ injury. Cross-cascade activation of the complement system, the contact system, and the coagulation system, as well as the mechanical forces of the circuitry are very important pathophysiological mechanisms, likely leading to neutrophil activation and the production of neutrophil extracellular traps (NETs). NETs may have the potential to cause organ damage, generating interest in their study as potential therapeutic targets for ECMO-related acute organ injury. Therefore, this article comprehensively summarized the mechanism of neutrophils activation and NETs formation following ECMO treatment and their actions on acute organ injury.

Remimazolam inhibits postoperative cognitive impairment after cardiopulmonary bypass by alleviating neuroinflammation and promoting microglia M2 polarization

Postoperative cognitive impairment (POCD) is a complication of cardiopulmonary bypass (CPB). Remimazolam is an ultra-short acting benzodiazepine that can be used for anesthesia or sedation during surgery. This study investigated the role of remimazolam in inflammasome activation and microglia polarization using CPB rat model and lipopolysaccharide (LPS)-induced microglia model. The cognitive function of rats was evaluated by Morris water maze. TUNEL assay was performed to detect apoptosis. Inflammatory cytokines concentration were analyzed by enzyme-linked immunosorbent assay. Reverse transcription-polymerase chain reaction was used to assess the expression of inflammasome and M1/M2-related microglia markers. Flow cytometry was performed to evaluate the expression of CD16/32 and CD206 in microglia. The results showed that remimazolam improved the memory and learning abilities in CPB rats. CPB rats and LPS-treated microglia showed increased apoptosis, pro-inflammatory cytokines level, and inflammasome expression as well as decreased microglia activation, while the results were reversed after remimazolam treatment. Besides, remimazolam treatment promoted the expression of M2-related markers in LPS-treated microglia. Nigericin treatment reversed the increased M2-related mRNA levels and the decreased apoptosis and inflammatory responses induced by remimazolam treatment. In conclusion, remimazolam attenuated POCD after CPB through regulating neuroinflammation and microglia M2 polarization, suggesting a new insight into the clinical treatment of POCD after CPB.

The Effects of Oxygen-Derived Free-Radical Scavengers During Normothermic Ex-Situ Heart Perfusion

Oxidative stress occurs during ex-situ heart perfusion (ESHP) and may negatively affect functional preservation of the heart. We sought to assess the status of key antioxidant enzymes during ESHP, and the effects of augmenting these antioxidants on the attenuation of oxidative stress and improvement of myocardial and endothelial preservation in ESHP. Porcine hearts were perfused for 6 hours with oxygen-derived free-radical scavengers polyethylene glycol (PEG)-catalase or PEG-superoxide dismutase (SOD) or with naive perfusate (control). The oxidative stress-related modifications were determined in the myocardium and coronary vasculature, and contractile function, injury, and endothelial integrity were compared between the groups. The activity of key antioxidant enzymes decreased and adding catalase and SOD restored the enzyme activity. Cardiac function and endothelial integrity were preserved better with restored catalase activity. Catalase and SOD both decreased myocardial injury and catalase reduced ROS production and oxidative modification of proteins in the myocardium and coronary vasculature. The activity of antioxidant enzymes decrease in ESHP. Catalase may improve the preservation of cardiac function and endothelial integrity during ESHP. While catalase and SOD may both exert cardioprotective effects, unbalanced SOD and catalase activity may paradoxically increase the production of reactive species during ESHP.

Risk factors for postoperative delirium in frail elderly patients undergoing on-pump cardiac surgery and development of a prediction model-a prospective observational study

Background

To identify the risk factors for postoperative delirium (POD) after cardiac surgery in frail elderly patients and develop a receiver operating characteristic (ROC) prediction model to confirm the effectiveness.

Methods

This was a prospective observational study, patients were assessed preoperatively according to the frailty index (FI) scale. Cerebral (SctO2) was assessed at different time points using near-infrared spectroscopy (NIRS). On the basis of the occurrence of POD within 7 days after surgery, patients were divided into POD and non-POD groups. Risk factors were analyzed using logistic regression analysis, while their predictive values were evaluated using the receiver operating characteristic curve analysis.

Results

POD was significantly associated with frailty, lower preoperative MMSE scores, hyperlipidemia, diabetes, cerebrovascular disease, lower hemoglobin level, lower albumin level, longer operation time, longer CPB time, lower SctO2 at T5, and lower SctO2baseline (P < 0.05). SrtO2 and SmtO2 did not differ significantly between groups. FI, preoperative MMSE score, and operation time as independent risk factors (P < 0.05). Significant predictive value was demonstrated in all 3 variables (P < 0.001; respectively). Among them, high sensitivity and specificity were observed with the FI (cut-off value 0.27, sensitivity 75%, specificity 73.5%) and operation time (cut-off value 237.5, sensitivity 62.5%, specificity 78.6%).

Conclusions

The FI, preoperative MMSE score, and operation time were independent risk factors for POD in elderly patients after cardiac surgery, with high predictive value observed with the FI and operation time. Cerebral oxygen saturation was associated with POD but was not an independent risk factor.

Clinical Trial Registration

Chinese Clinical Trail Registry, No: chictr2200056038.

Cardioprotection in cardiovascular surgery

Since the invention of cardiopulmonary bypass, cardioprotective strategies have been investigated to mitigate ischemic injury to the heart during aortic cross-clamping and reperfusion injury with cross-clamp release. With advances in cardiac surgical and percutaneous techniques and post-operative management strategies including mechanical circulatory support, cardiac surgeons are able to operate on more complex patients. Therefore, there is a growing need for improved cardioprotective strategies to optimize outcomes in these patients. This review provides an overview of the basic principles of cardioprotection in the setting of cardiac surgery, including mechanisms of cardiac injury in the context of cardiopulmonary bypass, followed by a discussion of the specific approaches to optimizing cardioprotection in cardiac surgery, including refinements in cardiopulmonary bypass and cardioplegia, ischemic conditioning, use of specific anesthetic and pharmaceutical agents, and novel mechanical circulatory support technologies. Finally, translational strategies that investigate cardioprotection in the setting of cardiac surgery will be reviewed, with a focus on promising research in the areas of cell-based and gene therapy. Advances in this area will help cardiologists and cardiac surgeons mitigate myocardial ischemic injury, improve functional post-operative recovery, and optimize clinical outcomes in patients undergoing cardiac surgery.

Phenotyping Refractory Cardiogenic Shock Patients Receiving Venous-Arterial Extracorporeal Membrane Oxygenation Using Machine Learning Algorithms

Background

This study used machine learning to categorize cardiogenic shock (CS) patients treated with venous-arterial extracorporeal membrane oxygenation (VA-ECMO) into distinct phenotypes. Subsequently, it aimed to clarify the wide mortality variance observed in refractory CS, attributing it to the condition's inherent heterogeneity.

Methods

This study enrolled a cohort of CS patients who received VA-ECMO support. By employing rigorous machine learning (ML) techniques, we generated and validated clusters based on determinants identified through algorithmic analysis. These clusters, characterized by distinct clinical outcomes, facilitated the examination of clinical and laboratory profiles to enhance the understanding of patient responses to VA-ECMO treatment.

Results

In a study of 210 CS patients undergoing VA-ECMO treatment, 70.5% were male with a median age of 62, ranging from 53 to 67 years. Survival rates were 67.6% during VA-ECMO and 49.5% post-discharge. Patients were classified into three phenotypes based on the clinical and laboratory findings: "platelet preserved (I)", those with stable platelet counts, "hyperinflammatory (II)", those indicating significant inflammation, and "hepatic-renal (III)", those showing compromised liver and kidney functions. Mortality rates (25.0%, 52.8%, and 55.9% for phenotypes I, Ⅱ, and Ⅲ, respectively (p = 0.005)) varied significantly among these groups, highlighting the importance of phenotype identification in patient management.

Conclusions

This study identified three distinct phenotypes among refractory CS patients treated using VA-ECMO, each with unique clinical characteristics and mortality risks. Thus, highlighting the importance of early detection and targeted intervention, these findings suggest that proactive management could improve outcomes for those showing critical signs.

Cardiac Surgery-Associated Acute Kidney Injury

AKI is a common and serious complication of cardiac surgery that has a significant impact on patient morbidity and mortality. The Kidney Disease Improving Global Outcomes definition of AKI is widely used to classify and identify AKI associated with cardiac surgery (cardiac surgery-associated AKI [CSA-AKI]) on the basis of changes in serum creatinine and/or urine output. There are various preoperative, intraoperative, and postoperative risk factors for the development of CSA-AKI which should be recognized and addressed as early as possible to expedite its diagnosis, reduce its occurrence, and prevent or ameliorate its devastating complications. Crucial issues are the inaccuracy of serum creatinine as a surrogate parameter of kidney function in the perioperative setting of cardiothoracic surgery and the necessity to discover more representative markers of the pathophysiology of AKI. However, except for the tissue inhibitor of metalloproteinase-2 and insulin-like growth factor binding protein 7 ratio, other diagnostic biomarkers with an acceptable sensitivity and specificity are still lacking. This article provides a comprehensive review of various aspects of CSA-AKI, including pathogenesis, risk factors, diagnosis, biomarkers, classification, prevention, and treatment management.

Severe coagulopathy and inflammation occurred after resection of giant right ventricular intimal sarcoma with cardiopulmonary bypass: a case report

BACKGROUND

Primary malignant cardiac tumors are rare in clinic, and surgical resection under cardiopulmonary bypass (CPB) remains the main treatment. The non-physiological perfusion process of CPB leads to contact activation, and the resulting coagulopathy and systemic inflammatory response syndrome (SIRS) are common complications. However, it is difficult to predict the impact of foreign tumor fragments on this pathophysiological process once they enter the bloodstream, making this phenomenon more complex and challenging.

CASE PRESENTATION

We report a case of cardiac intimal sarcoma who developed severe coagulopathy and widespread inflammation after excision of massive right ventricular tumor and replacement of tricuspid valve by median sternotomy under CPB. Although the procedure was expected to cause tumor cell necrosis and precautions were taken, uncontrolled massive postoperative bleeding, persistent fever, abnormally elevated inflammatory markers, and recurrent malignant arrhythmias occurred after surgery. In addition to common factors, the most possible underlying mechanism is contact activation triggered following surgical procedure for intimal sarcoma with CPB.

CONCLUSION

Patients with intracardiac malignant tumors are at a high risk for serious contact activation during CPB. Preventive application of comprehensive anti-inflammatory measures such as drugs and adsorptive CPB technology, as well as point-of-care (POC) monitoring of coagulation status will be helpful for individualized guidance and optimization of CPB management, and improvement of patient prognosis.

Inflammatory Progression in Patients Undergoing Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is identified as a novel therapeutic strategy that offers short-term support to the metabolism of the heart and lungs in humans. Recently, the clinical centers, which provide ECMO has increased rapidly worldwide. The indications for the use of ECMO in daily clinical practice were broadened dynamically. However, even with the widespread adoption of ECMO, it still remains significant morbidity and mortality, and the underlying mechanisms are still not elucidated. Notably, one of the vital complications during ECMO was proposed as the inflammatory progression within the extracorporeal circulation. via the development of inflammatory response, patients with ECMO may further suffer from systemic inflammatory response syndrome (SIRS), posing serious risks to human health. Recently, growing evidence confirmed that through exposure of blood into the ECMO circuit could lead to the stimulation of the immune system which also facilitated the inflammatory response and systemic impaired. In the current review, the pathological development of inflammatory progression in patients with ECMO is well-listed. Furthermore, the relationship between immune-related activation and the development of inflammation is also summarized, which may further help us to decide the therapeutic strategies in daily clinical practice.

Biochemical Changes in Cardiopulmonary Bypass in Cardiac Surgery: New Insights

Patients undergoing coronary revascularization with extracorporeal circulation or cardiopulmonary bypass (CPB) may develop several biochemical changes in the microcirculation that lead to a systemic inflammatory response. Surgical incision, post-CPB reperfusion injury and blood contact with non-endothelial membranes can activate inflammatory signaling pathways that lead to the production and activation of inflammatory cells, with cytokine production and oxidative stress. This inflammatory storm can cause damage to vital organs, especially the heart, and thus lead to complications in the postoperative period. In addition to the organic pathophysiology during and after the period of exposure to extracorporeal circulation, this review addresses new perspectives for intraoperative treatment and management that may lead to a reduction in this inflammatory storm and thereby improve the prognosis and possibly reduce the mortality of these patients.

Long term outcomes after normothermic machine perfusion in liver transplantation -experience at a single North American centre

Normothermic machine perfusion (NMP) has emerged as a valuable tool in the preservation of liver allografts before transplantation. Randomized trials have shown that replacing static cold storage (SCS) with NMP reduces allograft injury and improves graft utilization. The University of Alberta's liver transplant program was one of the early adopters of NMP in North America. Herein, we describe our seven-year experience applying NMP to extend preservation time in liver transplantation using a 'back-to-base' approach. From 2015 to 2021, 79 livers were transplanted following NMP compared to 386 after SCS only. NMP livers were preserved for a median time of 847min compared to 288.5min in the SCS cohort (p<0.0001). Despite this, we observed significantly improved 30-day graft survival (p=0.030), though no differences in long term patient survival, major complications or biliary or vascular complications. We also found that while SCS time was strongly associated with increased graft failure at one year in the SCS cohort (p=0.006), there was no such association amongst NMP livers (p=0.171). Our experience suggests that NMP can safely extend the total preservation time of liver allografts without increasing complications.

Impact of early pericardial fluid chymase activation after cardiac surgery

Introduction

Chymase is a highly destructive serine protease rapidly neutralized in the circulation by protease inhibitors. Here we test whether pericardial fluid (PCF) chymase activation and other inflammatory biomarkers determine intensive care unit length of stay, and explore mechanisms of chymase delivery by extracellular vesicles to the heart.

Methods

PCF was collected from adult patients (17 on-pump; 13 off-pump) 4 h after cardiac surgery. Extracellular vesicles (EVs) containing chymase were injected into Sprague-Dawley rats to test for their ability to deliver chymase to the heart.

Results

The mean intensive care unit (ICU) stay and mean total length of stay was 2.17 ± 3.8 days and 6.41 ± 1.3 days respectively. Chymase activity and 32 inflammatory markers did not differ in on-pump vs. off-pump cardiac surgery. Society of Thoracic Surgeons Predicted Risk of Morbidity and Mortality Score (STS-PROM), 4-hour post-surgery PCF chymase activity and C-X-C motif chemokine ligand 6 (CXCL6) were all independent predictors of ICU and total hospital length of stay by univariate analysis. Mass spectrometry of baseline PCF shows the presence of serine protease inhibitors that neutralize chymase activity. The compartmentalization of chymase within and on the surface of PCF EVs was visualized by immunogold labeling and transmission electron microscopy. A chymase inhibitor prevented EV chymase activity (0.28 fmol/mg/min vs. 14.14 fmol/mg/min). Intravenous injection of PCF EVs obtained 24 h after surgery into Sprague Dawley rats shows diffuse human chymase uptake in the heart with extensive cardiomyocyte damage 4 h after injection.

Discussion

Early postoperative PCF chymase activation underscores its potential role in cardiac damage soon after on- or off-pump cardiac surgery. In addition, chymase in extracellular vesicles provides a protected delivery mechanism from neutralization by circulating serine protease inhibitors.

Overview of oxidative stress and the role of micronutrients in critical illness

Inflammation and oxidative stress represent physiological response mechanisms to different types of stimuli and injury during critical illness. Its proper regulation is fundamental to cellular and organismal survival and are paramount to outcomes and recovery from critical illness. A proper maintenance of the delicate balance between inflammation, oxidative stress, and immune response is crucial for resolution from critical illness with important implications for patient outcome. The extent of inflammation and oxidative stress under normal conditions is limited by the antioxidant defense system of the human body, whereas the antioxidant capacity is commonly significantly compromised, and serum levels of micronutrients and vitamins significantly depleted in patients who are critically ill. Hence, the provision of antioxidants and anti-inflammatory nutrients may help to reduce the extent of oxidative stress and therefore improve clinical outcomes in patients who are critically ill. As existing evidence of the beneficial effects of antioxidant supplementation in patients who are critically ill is still unclear, actual findings about the most promising anti-inflammatory and antioxidative candidates selenium, vitamin C, zinc, and vitamin D will be discussed in this narrative review. The existing evidence provided so far demonstrates that several factors need to be considered to determine the efficacy of an antioxidant supplementation strategy in patients who are critically ill and indicates the need for adequately designed multicenter prospective randomized control trials to evaluate the clinical significance of different types and doses of micronutrients and vitamins in selected groups of patients with different types of critical illness.

Diagnosis, pathophysiology and preventive strategies for cardiac surgery-associated acute kidney injury: a narrative review

Acute kidney injury (AKI) is a common and serious complication of cardiac surgery and is associated with increased mortality and morbidity, accompanied by a substantial economic burden. The pathogenesis of cardiac surgery-associated acute kidney injury (CSA-AKI) is multifactorial and complex, with a variety of pathophysiological theories. In addition to the existing diagnostic criteria, the exploration and validation of biomarkers is the focus of research in the field of CSA-AKI diagnosis. Prevention remains the key to the management of CSA-AKI, and common strategies include maintenance of renal perfusion, individualized blood pressure targets, balanced fluid management, goal-directed oxygen delivery, and avoidance of nephrotoxins. This article reviews the pathogenesis, definition and diagnosis, and pharmacological and nonpharmacological prevention strategies of AKI in cardiac surgical patients.

Postoperative Lactate Predicts In-Hospital Death in Patients with Acute Type A Aortic Dissection

Several studies have found that lactate correlates with surgical outcomes in patients with heart disease. However, the prognostic value of postoperative lactate in patients with acute type A aortic dissection (AAAD) remains unclear. This study aimed to investigate the relationship between postoperative lactate and in-hospital mortality in patients with AAAD. Patients who underwent AAAD surgery at Fujian Cardiac Medical Center from February 2020 to January 2022 were enrolled in this retrospective study. Correlations between in-hospital mortality and various parameters, including lactate, were investigated. A total of 357 patients were included in this study, 58 of which died. Multivariate logistic regression analysis revealed that body mass index (BMI) (odds ratio [OR] = 1.099, 95% confidence interval [CI]: 1.017-1.188, P = 0.017), cardiopulmonary bypass (CPB) time (OR = 1.005; 95% CI: 1.000-1.010, P = 0.039), and lactate (OR = 1.291, 95% CI: 1.182-1.409, P < 0.001) were independent risk factors for in-hospital mortality in AAAD patients. Receiver operating characteristic (ROC) curve analysis showed that lactate had a moderate power for in-hospital mortality (area under the curve [AUC] = 0.729, 95% CI: 0.647-0.810, P < 0.001). Furthermore, the combination of lactate, BMI, and CPB time showed better performance (AUC = 0.780; 95% CI: 0.706-0.854, P < 0.001) in predicting in-hospital mortality than in using these variables independently. Among patients undergoing AAAD surgery, postoperative lactate was significantly associated with in-hospital mortality. Lactate can be used as a potential predictor of in-hospital mortality. The combination of lactate, BMI, and CPB time showed better performance in predicting in-hospital mortality than using single one.

Fluid overload and mortality in critically ill patients with severe heart failure and cardiogenic shock-An observational cohort study

OBJECTIVE

Patients with heart failure (HF) and cardiogenic shock are especially prone to the negative effects of fluid overload (FO); however, fluid resuscitation in respective patients is sometimes necessary resulting in FO. We aimed to study the association of FO at ICU discharge with 30-day mortality in patients admitted to the ICU due to severe heart failure and/or cardiogenic shock.

METHODS

Retrospective, single-center cohort study. Patients with admission diagnoses of severe HF and/or cardiogenic shock were eligible. The following exclusion criteria were applied: (I) patients younger than 16 years, (II) patients admitted to our intermediate care unit, and (III) patients with incomplete data to determine FO at ICU discharge. We used a cumulative weight-adjusted definition of fluid balance and defined more than 5% as FO. The data were analyzed by univariate and adjusted univariate logistic regression.

RESULTS

We included 2,158 patients in our analysis. 185 patients (8.6%) were fluid overloaded at ICU discharge. The mean FO in the FO group was 7.2% [interquartile range (IQR) 5.8-10%]. In patients with FO at ICU discharge, 30-day mortality was 22.7% compared to 11.7% in non-FO patients (p < 0.001). In adjusted univariate logistic regression, we did not observe any association of FO at discharge with 30-day mortality [odds ratio (OR) 1.48; 95% confidence interval (CI) 0.81-2.71, p = 0.2]. No association between FO and 30-day mortality was found in the subgroups with HF only or cardiogenic shock (all p > 0.05). Baseline lactate (adjusted OR 1.27; 95% CI 1.13-1.42; p < 0.001) and cardiac surgery at admission (adjusted OR 1.94; 95% CI 1.0-3.76; p = 0.05) were the main associated factors with FO at ICU discharge.

CONCLUSION

In patients admitted to the ICU due to severe HF and/or cardiogenic shock, FO at ICU discharge seems not to be associated with 30-day mortality.

TEMPORAL TRENDS IN THE USE AND OUTCOMES OF TEMPORARY MECHANICAL CIRCULATORY SUPPORT AS A BRIDGE TO CARDIAC TRANSPLANTATION IN SPAIN. FINAL REPORT OF THE ASIS-TC STUDY

BACKGROUND

We aimed to describe recent trends in the use and outcomes of temporary mechanical circulatory support (MCS) as a bridge to heart transplantation (HTx) in Spain.

METHODS

Retrospective case-by-case analysis of 1,036 patients listed for emergency HTx while on temporary MCS in 16 Spanish institutions from January 1st, 2010 to December 31st, 2020. Patients were classified in 3 eras according to changes in donor allocation criteria (Era 1: January 2010/May 2014; Era 2: June 2014/May 2017; Era 3: June 2017/December 2020).

RESULTS

Over time, the proportion of candidates listed with intra-aortic balloon pumps decreased (Era 1 = 55.9%, Era 2 = 32%, Era 3 = 0.9%; p < 0.001), while the proportion of candidates listed with surgical continuous-flow temporary VADs (Era 1 = 10.6%, Era 2 = 32%, Era 3 = 49.1%; p < 0.001) and percutaneous VADs (Era 1 = 0.3%, Era 2 = 6.3%; Era 3 = 17.2%; p < 0.001) increased. Rates of HTx increased from Era 1 (79.4%) to Era 2 (87.8%), and Era 3 (87%) (p = 0.004), while rates of death before HTx decreased (Era 1 = 17.7%; Era 2 = 11%, Era 3 = 12.4%; p = 0.037) Median time from listing to HTx increased in patients supported with intra-aortic balloon pumps (Era 1 = 8 days, Era 2 = 15 days; p < 0.001) but remained stable in other candidates (Era 1 = 6 days; Era 2 = 5 days; Era 3 = 6 days; p = 0.134). One-year post-transplant survival was 71.4% in Era 1, 79.3% in Era 2, and 76.5% in Era 3 (p = 0.112). Preoperative bridging with ECMO was associated with increased 1-year post-transplant mortality (adjusted HR=1.71; 95% CI 1.15-2.53; p = 0.008).

CONCLUSIONS

During the period 2010 to 2020, successive changes in the Spanish organ allocation protocol were followed by a significant increase of the rate of HTx and a significant reduction of waiting list mortality in candidates supported with temporary MCS. One-year post-transplant survival rates remained acceptable.

A Functional Network Driven by MicroRNA-125a Regulates Monocyte Trafficking in Acute Inflammation

During the onset of acute inflammation, rapid trafficking of leukocytes is essential to mount appropriate immune responses towards an inflammatory insult. Monocytes are especially indispensable for counteracting the inflammatory stimulus, neutralising the noxa and reconstituting tissue homeostasis. Thus, monocyte trafficking to the inflammatory sites needs to be precisely orchestrated. In this study, we identify a regulatory network driven by miR-125a that affects monocyte adhesion and chemotaxis by the direct targeting of two adhesion molecules, i.e., junction adhesion molecule A (JAM-A), junction adhesion molecule-like (JAM-L) and the chemotaxis-mediating chemokine receptor CCR2. By investigating monocytes isolated from patients undergoing cardiac surgery, we found that acute yet sterile inflammation reduces miR-125a levels, concomitantly enhancing the expression of JAM-A, JAM-L and CCR2. In contrast, TLR-4-specific stimulation with the pathogen-associated molecular pattern (PAMP) LPS, usually present within the perivascular inflamed area, resulted in dramatically induced levels of miR-125a with concomitant repression of JAM-A, JAM-L and CCR2 as early as 3.5 h. Our study identifies miR-125a as an important regulator of monocyte trafficking and shows that the phenotype of human monocytes is strongly influenced by this miRNA, depending on the type of inflammatory stimulus.