A tidal volume of 7 mL/kg PBW or higher may be safe for COVID-19 patients

PURPOSE

The novel coronavirus disease (COVID-19) has revived the debate on the optimal tidal volume during acute respiratory distress syndrome (ARDS). Some experts recommend 6 mL/kg of predicted body weight (PBW) for all patients, while others suggest 7-9 mL/kg PBW for those with compliance >50 mL/cmH2O. We investigated whether a tidal volume ≥ 7 ml/kg PBW may be safe in COVID-19 patients, particularly those with compliance >50 mL/cmH2O.

MATERIALS AND METHODS

This secondary analysis of a multicenter study compares the Intensive Care Unit (ICU) mortality among 600 patients ventilated with <7 or ≥ 7 mL/kg PBW. Compliance was categorized as <40, 40-50, or > 50 mL/cmH2O.

RESULTS

346 patients were ventilated with <7 (6.2 ± 0.5) mL/kg PBW and 254 with ≥7 (7.9 ± 0.9) mL/kg PBW. ICU mortality was 33 % and 29 % in the two groups (p = 0.272). At multivariable regression analysis, tidal volume ≥ 7 mL/kg PBW was associated with lower ICU mortality in the overall population (odds ratio: 0.62 [95 %-confidence interval: 0.40-0.95]) and in each compliance category.

CONCLUSIONS

A tidal volume ≥ 7 (up to 9) mL/kg PBW was associated with lower ICU mortality in these COVID-19 patients, including those with compliance <40 mL/cmH2O. This finding should be interpreted cautiously due to the retrospective study design.

TRIAL REGISTRATION

ClinicalTrails.govNCT04388670.

Neuroworsening in Moderate Traumatic Brain Injury

Patients with moderate traumatic brain injury (TBI) are at high risk for developing intracerebral complications and in particular neuroworsening (NW). NW can be unpredictable and may be an important risk factor for poor neurologic outcome and for increased mortality. NW is often a medical and surgical emergency, and it is, therefore, fundamental to identify patients at risk early because they require strict neuromonitoring and repeated neuroimaging. So far, there is no standardized and validated definition of NW. In this review, we aim to discuss the definition, risk factors, and management of patients with moderate TBI at high risk of NW.

Understanding ventilator-induced lung injury: The role of mechanical power

Mechanical ventilation stands as a life-saving intervention in the management of respiratory failure. However, it carries the risk of ventilator-induced lung injury. Despite the adoption of lung-protective ventilation strategies, including lower tidal volumes and pressure limitations, mortality rates remain high, leaving room for innovative approaches. The concept of mechanical power has emerged as a comprehensive metric encompassing key ventilator parameters associated with the genesis of ventilator-induced lung injury, including volume, pressure, flow, resistance, and respiratory rate. While numerous animal and human studies have linked mechanical power and ventilator-induced lung injury, its practical implementation at the bedside is hindered by calculation challenges, lack of equation consensus, and the absence of an optimal threshold. To overcome the constraints of measuring static respiratory parameters, dynamic mechanical power is proposed for all patients, regardless of their ventilation mode. However, establishing a causal relationship is crucial for its potential implementation, and requires further research. The objective of this review is to explore the role of mechanical power in ventilator-induced lung injury, its association with patient outcomes, and the challenges and potential benefits of implementing a ventilation strategy based on mechanical power.

Cerebrospinal Fluid Pressure Measurement and Infusion Studies Using Lumbar Puncture

Lumbar puncture provides an easy way of accessing the subarachnoid space. Measuring of the opening cerebrospinal fluid pressure is the most commonly used method of evaluating intracranial pressure but provides basic snapshot information only. Further insights into cerebrospinal fluid dynamics can be obtained through infusion studies, which rely on measurement of the degree of pressure change in response to addition of fluid volume into the subarachnoid space. The authors describe applications of these 2 techniques pertinent to a practicing neuroradiologist, who may be asked to assist with fluoroscopy-guided lumbar puncture in patients with increased body mass index or difficult spine anatomy.

Feasibility of estimating tidal volume from electrocardiograph-derived respiration signal and respiration waveform

PURPOSE

Estimating tidal volume (VT) from electrocardiography (ECG) can be quite useful during deep sedation or spinal anesthesia since it eliminates the need for additional monitoring of ventilation. This study aims to validate and compare VT estimation methodologies based on ECG-derived respiration (EDR) using real-world clinical data.

MATERIALS AND METHODS

We analyzed data from 90 critically ill patients for general analysis and two critically ill patients for constrained analysis. EDR signals were generated from ECG data, and VT was estimated using impedance-based respiration waveforms. Linear regression and deep learning models, both subject-independent and subject-specific, were evaluated using mean absolute error and Pearson correlation.

RESULTS

There was a strong short-term correlation between VT and the respiration waveform (r = 0.78 and 0.96), which weakened over longer periods (r = 0.23 and - 0.16). VT prediction models performed poorly in the general population (R2 = 0.17) but showed satisfactory performance in two constrained patient records using measured respiration waveforms (R2 = 0.84 to 0.94).

CONCLUSION

Although EDR-based VT estimation is promising, current methodologies are limited by noisy ICU ECG signals, but controlled environment data showed significant short-term correlations with measured respiration waveforms. Future studies should develop reliable EDR extraction procedures and improve predictive models to broaden clinical applications.

Dachaihu decoction alleviates septic intestinal epithelial barrier disruption via PI3K/AKT pathway based on transcriptomics and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Dachaihu decoction (DCH) is a famous and ancient TCM formula, extensively utilized for over 1800 years in treating gastrointestinal and inflammatory conditions. Our previous study showed that DCH ameliorated intestinal damage and modulated the gut microflora in septic rats. However, the material basis for these effects and the underlying mechanism of action remains ill-defined. We aimed to explore the pharmaceutical ingredients of DCH and its mechanism in mitigating sepsis-induced intestinal epithelial barrier disruption (IEBD).

MATERIALS AND METHODS

Ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) was used to identify DCH composition. A septic rat model and Caco-2 cells were employed to investigate DCH's effects on IEBD. Transcriptomics and network pharmacology were used to predict potential mechanisms, which were further validated by molecular docking and dynamics simulations. The Modified Murine Sepsis Score (mMSS) and histological assessments were performed. Serum fluorescence intensity of FD4 and the expression of Occludin were evaluated to assess intestinal barrier integrity. And p-PI3K P85, PI3K P85, p-AKT, AKT, Bax and Bcl-2 were determined by Western blot. Cell viability was determined using CCK-8 assay, IL-6 and TNF-α by ELISA and quantitative Real-time PCR (RT-qPCR). The integrity and permeability of single layer of Caco-2 cells were assessed via transepithelial resistance (TEER), alkaline phosphatase (ALP) activity and FD4 permeability.

RESULTS

UHPLC-HRMS identified 180 compounds in DCH. DCH significantly reduced mMSS, improved pathological conditions in the ileum, decreased FD4 serum fluorescence, and enhanced Occludin expression. Transcriptomic and network pharmacology analyses identified the PI3K/AKT pathway as a critical mechanism of action. Molecular docking and dynamics simulations confirmed strong binding of DCH components to PIK3R1. DCH upregulated p-PI3K and p-AKT in ileum tissue of septic rats. DCH improved cell viability, decreased IL-6 and TNF-α, promoted cell survival and Occludin level, and upregulated p-PI3K and p-AKT in LPS-stimulated Caco-2 cells. DCH also maintained TEER, ALP activity and decreased FD4 permeability and these effects were reversed by PI3K inhibitor, LY294002. DCH also downregulated Bax expression and increased Bcl-2 levels in both septic rats and LPS-stimulated Caco-2 cells.

CONCLUSION

DCH ameliorates sepsis-induced IEBD via PI3K/AKT pathway activation, offering a novel therapeutic perspective for sepsis-related intestinal dysfunction.

Evaluation of Vaccines and Therapeutics Against Marburg Virus in Nonhuman Primate Models

Marburg virus (MARV) has caused sporadic outbreaks of severe hemorrhagic fever in Africa in humans and nonhuman primates (NHPs) and has the potential to be used as a biological weapon. Currently, there are no licensed vaccines or therapeutics to respond to outbreaks or deliberate misuse. Vaccine and therapeutic efficacy testing against MARV requires animal models that accurately mimic human disease. In vitro testing in cell culture cannot appropriately model the complex immunological host responses required to accurately predict efficacy in humans, which will ultimately be required for licensure of a medical countermeasure (MCM). While small animal models for MARV have been valuable for dissecting disease processes and the screening of vaccine and drug candidates, there are several caveats to their use including required adaptation of the virus, lack of host-specific reagents, or the need of an immunocompromised host. Conversely, the NHP MARV disease model addresses all shortcomings of small animal models and closely recapitulates all hallmark features of human disease. As such, NHPs have served as the "gold standard" for testing filovirus MCMs and will most likely be required for regulatory approval. Here, we describe the use of NHPs for vaccine and therapeutic evaluation against MARV.

The management of new-onset atrial fibrillation in critical illness: an update on current therapeutic options

PURPOSE OF REVIEW

New-onset atrial fibrillation (NOAF) is the most prevalent arrhythmia among critically ill patients, correlating with heightened morbidity and mortality rates. Current evidence for managing NOAF in this patient population is limited.

RECENT FINDINGS

Numerous meta-analyses have been conducted to assess the efficacy of atrial fibrillation treatments in acute settings, including rate or rhythm control strategies, anticoagulation, and intensive care interventions. The employment of β-blockers for rate control appears to confer greater benefits in critically ill patients. However, the advantage of anticoagulation remains ambiguous because of bleeding risks, which is partly attributed to the scarcity of evidence in the complex context of critical illness. Approximately one-third of patients with transient atrial fibrillation face recurrence within a year. Therefore, vigilant posthospitalization follow-up and monitoring should be considered for high-risk patients to detect atrial fibrillation recurrence. Long-term anticoagulation strategies should be tailored to individual patient profiles, weighing the risks of thromboembolism.

SUMMARY

Factors predicting atrial fibrillation recurrence include age, the burden of atrial fibrillation, and atrial size. There are significant knowledge gaps concerning NOAF in critically ill patients, highlighting the need for further research, particularly randomized clinical trials.

Balanced Solution Versus Normal Saline in Predicted Severe Acute Pancreatitis: A Stepped Wedge Cluster Randomized Trial

OBJECTIVE

To compare the effect of balanced multielectrolyte solutions (BMESs) versus normal saline (NS) for intravenous fluid on chloride levels and clinical outcomes in patients with predicted severe acute pancreatitis (pSAP).

BACKGROUND

Isotonic crystalloids are recommended for initial fluid therapy in acute pancreatitis, but whether the use of BMES in preference to NS confers clinical benefits is unknown.

METHODS

In this multicenter, stepped-wedge, cluster-randomized trial, we enrolled patients with pSAP (acute physiology and chronic health evaluation II score ≥8 and C-reactive protein >150 mg/L) admitted within 72 hours of the advent of symptoms. The study sites were randomly assigned to staggered start dates for a one-way crossover from the NS phase (NS for intravenous fluid) to the BMES phase (sterofudin for intravenous fluid). The primary endpoint was the serum chloride concentration on trial day 3. Secondary endpoints included a composite of clinical and laboratory measures.

RESULTS

Overall, 259 patients were enrolled from 11 sites to receive NS (n = 147) or BMES (n = 112). On trial day 3, the mean chloride level was significantly lower in patients who received BMES [101.8 mmol/L (SD: 4.8) vs 105.8 mmol/L (SD: 5.9), difference -4.3 mmol/L (95% CI: -5.6 to -3.0 mmol/L) ; P < 0.001]. For secondary endpoints, patients who received BMES had less systemic inflammatory response syndrome (19/112, 17.0% vs 43/147, 29.3%, P = 0.024) and increased organ failure-free days [3.9 days (SD: 2.7) vs 3.5 days (SD: 2.7), P < 0.001] by trial day 7. They also spent more time alive and out of the intensive care unit [26.4 days (SD: 5.2) vs 25.0 days (SD: 6.4), P = 0.009] and hospital [19.8 days (SD: 6.1) vs 16.3 days (SD: 7.2), P < 0.001] by trial day 30.

CONCLUSIONS

Among patients with pSAP, using BMES in preference to NS resulted in a significantly more physiological serum chloride level, which was associated with multiple clinical benefits (Trial registration number: ChiCTR2100044432).

The intricate interactions between inflammasomes and bacterial pathogens: Roles, mechanisms, and therapeutic potentials

Inflammasomes are intracellular multiprotein complexes that consist of a sensor, an adaptor, and a caspase enzyme to cleave interleukin (IL)-1β and IL-18 into their mature forms. In addition, caspase-1 and -11 activation results in the cleavage of gasdermin D to form pores, thereby inducing pyroptosis. Activation of the inflammasome and pyroptosis promotes host defense against pathogens, whereas dysregulation of the inflammasome can result in various pathologies. Inflammasomes exhibit versatile microbial signal detection, directly or indirectly, through cellular processes, such as ion fluctuations, reactive oxygen species generation, and the disruption of intracellular organelle function; however, bacteria have adaptive strategies to manipulate the inflammasome by altering microbe-associated molecular patterns, intercepting innate pathways with secreted effectors, and attenuating inflammatory and cell death responses. In this review, we summarize recent advances in the diverse roles of the inflammasome during bacterial infections and discuss how bacteria exploit inflammasome pathways to establish infections or persistence. In addition, we highlight the therapeutic potential of harnessing bacterial immune subversion strategies against acute and chronic bacterial infections. A more comprehensive understanding of the significance of inflammasomes in immunity and their intricate roles in the battle between bacterial pathogens and hosts will lead to the development of innovative strategies to address emerging threats posed by the expansion of drug-resistant bacterial infections.

Sustainability of shear stress conditioning in endothelial colony-forming cells compared to human aortic endothelial cells to underline suitability for tissue-engineered vascular grafts

The endothelialization of cardiovascular implants is supposed to improve the long-term patency of these implants. In addition, in previous studies, it has been shown, that the conditioning of endothelial cells by dynamic cultivation leads to the expression of an anti-thrombogenic phenotype. For the creation of a tissue-engineered vascular graft (TEVG), these two strategies were combined to achieve optimal hemocompatibility. In a clinical setup, this would require the transfer of the already endothelialized construct from the conditioning bioreactor to the patient. Therefore, the reversibility of the dynamic conditioning of the endothelial cells with arterial-like high shear stress (20 dyn/cm2) was investigated to define the timeframe (tested in a range of up to 24 h) for the perseverance of dynamically induced phenotypical changes. Two types of endothelial cells were compared: endothelial colony-forming cells (ECFCs) and human aortic endothelial cells (HAECs). The results showed that ECFCs respond far more sensitively and rapidly to flow than HAECs. The resulting cell alignment and increased protein expression of KLF-2, Notch-4, Thrombomodulin, Tie2 and eNOS monomer was paralleled by increased eNOS and unaltered KLF-2 mRNA levels even under stopped-flow conditions. VCAM-1 mRNA and protein expression was downregulated under flow and did not recover under stopped flow. From these time kinetic results, we concluded, that the maximum time gap between the TEVG cultivated with autologous ECFCs in future reactor cultivations and the transfer to the potential TEVG recipient should be limited to ∼6 h.

Unraveling the pathogenesis of viral-induced pulmonary arterial hypertension: Possible new therapeutic avenues with mesenchymal stromal cells and their derivatives

Pulmonary hypertension (PH) is a severe condition characterized by elevated pressure in the pulmonary artery, where metabolic and mitochondrial dysfunction may contribute to its progression. Within the PH spectrum, pulmonary arterial hypertension (PAH) stands out with its primary pulmonary vasculopathy. PAH's prevalence varies from 0.4 to 1.4 per 100,000 individuals and is associated with diverse conditions, including viral infections such as HIV. Notably, recent observations highlight an increased occurrence of PAH among COVID-19 patients, even in the absence of pre-existing cardiopulmonary disorders. While current treatments offer partial relief, there's a pressing need for innovative therapeutic strategies, among which mesenchymal stromal cells (MSCs) and their derivatives hold promise. This review critically evaluates recent investigations into viral-induced PAH, encompassing pathogens like human immunodeficiency virus, herpesvirus, Cytomegalovirus, Hepatitis B and C viruses, SARS-CoV-2, and Human endogenous retrovirus K (HERKV), with a specific emphasis on mitochondrial dysfunction. Furthermore, we explore the underlying rationale driving novel therapeutic modalities, including MSCs, extracellular vesicles, and mitochondrial interventions, within the framework of PAH management.

Abbreviated Urine Collection Compared With 24-Hour Urine Collection for Measuring Creatinine Clearance in Adult Critically Ill Patients: A Systematic Review

OBJECTIVE

To evaluate the accuracy of abbreviated urine collection (≤12 hours) compared with 24-hour urine collection for measuring creatinine clearance (CrCl) in critically ill adult patients.

DATA SOURCES

We searched PubMed, Embase, Web of Science, Google Scholar, and ProQuest Dissertations and Thesis Global; screened reference lists of included studies; and contacted the authors when needed. English studies only were considered with no restriction on dates.

STUDY SELECTION AND DATA EXTRACTION

After duplicate removal, 2 reviewers screened titles/abstracts, reviewed full-text articles, and extracted data independently. Studies that compared abbreviated versus 24-hour urine collection for measuring CrCl were included. We assessed the risk of bias using the QUADAS-2 tool. We extracted correlation coefficients, mean prediction errors (ME)-as a measure of bias, and root mean squared prediction errors (RMSE)-as a measure of precision.

DATA SYNTHESIS

Five studies were included, comprising 528 adult critically ill adults from surgical, medical, and trauma intensive care units (ICUs). Three studies had high risk of bias, and 2 had low risk. The studies evaluated different durations of urine collection, including 30-minute, 2-hour, 4-hour, 6-hour, and 12-hour. Mean 24-hour CrCl ranged from 57 mL/min/1.73 m2 to 103 mL/min. Abbreviated urine collection led to CrCl that correlated well with the 24-hour measured CrCl (correlation coefficient ranged from 0.8 to 0.95). Mean prediction error ranged from 5 mL/min/1.73 m2 to 16 mL/min (from 8% to 25% of the 24-hour CrCl). Root mean squared prediction error calculated from 1 study was 30.5 mL/min/1.73 m2.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Abbreviated urine collection is used to measure CrCl for renal drug dosing in critically ill patients, but its accuracy is not well-established.

CONCLUSIONS

Abbreviated urine collection may overestimate CrCl compared with 24-hour urine collection. Larger, well-conducted studies are needed to evaluate the accuracy of CrCl measured using different durations of urine collection in critically ill patients.

MicroRNA-guided drug discovery for mitigating persistent pulmonary complications in critical COVID-19 survivors: A longitudinal pilot study

BACKGROUND AND PURPOSE

The post-acute sequelae of SARS-CoV-2 infection pose a significant global challenge, with nearly 50% of critical COVID-19 survivors manifesting persistent lung abnormalities. The lack of understanding about the molecular mechanisms and effective treatments hampers their management. Here, we employed microRNA (miRNA) profiling to decipher the systemic molecular underpinnings of the persistent pulmonary complications.

EXPERIMENTAL APPROACH

We conducted a longitudinal investigation including 119 critical COVID-19 survivors. A comprehensive pulmonary evaluation was performed in the short-term (median = 94.0 days after hospital discharge) and long-term (median = 358 days after hospital discharge). Plasma miRNAs were quantified at the short-term evaluation using the gold-standard technique, RT-qPCR. The analyses combined machine learning feature selection techniques with bioinformatic investigations. Two additional datasets were incorporated for validation.

KEY RESULTS

In the short-term, 84% of the survivors exhibited impaired lung diffusion (DLCO < 80% of predicted). One year post-discharge, 54.4% of this patient subgroup still presented abnormal DLCO. Four feature selection methods identified two specific miRNAs, miR-9-5p and miR-486-5p, linked to persistent lung dysfunction. The downstream experimentally validated targetome included 1473 genes, with heterogeneous enriched pathways associated with inflammation, angiogenesis and cell senescence. Validation studies using RNA-sequencing and proteomic datasets emphasized the pivotal roles of cell migration and tissue repair in persistent lung dysfunction. The repositioning potential of the miRNA targets was limited.

CONCLUSION AND IMPLICATIONS

Our study reveals early mechanistic pathways contributing to persistent lung dysfunction in critical COVID-19 survivors, offering a promising approach for the development of targeted disease-modifying agents.

LINKED ARTICLES

This article is part of a themed issue Non-coding RNA Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.2/issuetoc.

Clinical Comparison of Post-intensive Care Syndrome and Long Coronavirus Disease

Post-intensive care syndrome (PICS) encompasses persistent physical, psychological, and cognitive impairments. The coronavirus disease of 2019 (COVID-19) pandemic highlighted parallels between PICS and "long COVID". There is an overlap between the 2 in risk factors, symptoms, and pathophysiology. Physical impairments in both include weakness and fatigue. Cognitive impairments include executive dysfunction in PICS and "brain fog" in long COVID. Mental health issues consist of depression, anxiety, and posttraumatic stress disorder in both disease states. Long COVID and PICS impact families, with multifaceted effects on physical health, mental well-being, and socioeconomic stability. Understanding these syndromes is crucial for comprehensive patient care and family support.

Differential expression of keratin and keratin associated proteins are linked with hair loss condition in spontaneously mutated inbred mice

Hair loss condition is heritable and is influenced by multifactorial inheritance. In the present study, spontaneously mutated mice showed hair loss phenotype with defect in the first cycle of hair follicle formation leading to cyclic alopecia. These mutant mice follow autosomal recessive inheritance pattern. The transcriptomic profile and differential gene expression analysis of skin tissues by RNA-sequencing at different stages of hair cycle formation was performed. The genes with significant differential genes expression levels in each stage of hair cycle formation were identified and most of these genes were shown to be associated with keratinization process and hair follicle formation. Transcriptome profiling followed by QPCR validation revealed that mRNA levels of Krt16, Alox15, Fetub (upregulated) and Msx2 (downregulated) were significantly differentially expressed in mutant skin tissues during late anagen and catagen stages. Krt6b mRNA and protein levels were significantly higher in the mutant mice during all stages of first hair cycle formation. The present study provides basis for understanding the differential gene expression of hair-related genes, including keratinization-associated proteins and its relevance. These mutant mice can serve as a model for studying hair loss condition that can be further used in the identification, evaluation and treatment strategies for alopecia condition.

Unveiling the Influence of AI on Advancements in Respiratory Care: Narrative Review

BACKGROUND

Artificial intelligence is experiencing rapid growth, with continual innovation and advancements in the health care field.

OBJECTIVE

This study aims to evaluate the application of artificial intelligence technologies across various domains of respiratory care.

METHODS

We conducted a narrative review to examine the latest advancements in the use of artificial intelligence in the field of respiratory care. The search was independently conducted by respiratory care experts, each focusing on their respective scope of practice and area of interest.

RESULTS

This review illuminates the diverse applications of artificial intelligence, highlighting its use in areas associated with respiratory care. Artificial intelligence is harnessed across various areas in this field, including pulmonary diagnostics, respiratory care research, critical care or mechanical ventilation, pulmonary rehabilitation, telehealth, public health or health promotion, sleep clinics, home care, smoking or vaping behavior, and neonates and pediatrics. With its multifaceted utility, artificial intelligence can enhance the field of respiratory care, potentially leading to superior health outcomes for individuals under this extensive umbrella.

CONCLUSIONS

As artificial intelligence advances, elevating academic standards in the respiratory care profession becomes imperative, allowing practitioners to contribute to research and understand artificial intelligence's impact on respiratory care. The permanent integration of artificial intelligence into respiratory care creates the need for respiratory therapists to positively influence its progression. By participating in artificial intelligence development, respiratory therapists can augment their clinical capabilities, knowledge, and patient outcomes.

Current status of routine use of veno-arterial extracorporeal membrane oxygenation during lung transplantation

INTRODUCTION

Recently, there has been growing experience with utilizing a veno-arterial extracorporeal membrane oxygenator (VA ECMO) routinely during lung transplantation procedures. Yet, there is a lack of consensus on the protocols, benefits, and outcomes of routine VA ECMO use in lung transplantation.

AREAS COVERED

This article presents an overview of the current status of routine use of VA ECMO during lung transplantation, including rationale, protocols, applications, and outcomes.

EXPERT OPINION

Utilization of VA ECMO during lung transplantation has emerged as an alternative mechanical circulatory support modality to cardiopulmonary bypass, with growing evidence showing lower rates of peri-operative complications. Some groups took that further into routine application of VA ECMO during lung transplantation. The current available evidence suggests that routine utilization of VA ECMO during lung transplantation is associated with lower rates of primary graft dysfunction and improved early outcomes. Use of VA ECMO allows controlled reperfusion of the allograft and avoids an unplanned "crash" on pump in case of hemodynamic instability, which carries worse outcomes after lung transplantation. As a relatively new approach, further follow-up of growing experience, as well as prospective clinical trials, is necessary to develop a consensus about routine utilization of VA ECMO during lung transplantation.

Development and Evaluation of a Novel Drainage Cannula for Venoarterial Extracorporeal Membrane Oxygenation

A critical factor in thrombus formation during venoarterial extracorporeal membrane oxygenation (VA ECMO) is prothrombotic flow dynamics generated by the drainage cannula's design. This study aimed to create and evaluate a novel drainage cannula design which optimized blood flow dynamics to reduce thrombus formation. Computational fluid dynamics (CFD) was used to iteratively vary drainage cannula design parameters such as inner wall shape and side hole shape. The final novel design was then placed in an ex vivo blood circulation loop, and compared against a Bio-Medicus cannula (n = 6, each). Clot volume, hemolysis, and other parameters were measured to assess thrombus formation markers. The novel design consisted of a parabolic inner wall profile with closely spaced side holes angled at 30º to align with flow. When tested in the ex vivo loop, the novel design resulted in lower instances (two vs. four) and volumes of clot in the cannula (360.5 ± 254.8 vs. 1258.0 ± 651.7 µl) when compared to the Bio-Medicus cannula. Results from tests assessing hemolysis, platelet activation, and other thrombotic markers revealed a noninferior relationship between the novel and Bio-Medicus designs. Future work will explore the clinical applicability of these findings.

Umbilical cord-derived mesenchymal stem cells preferentially modulate macrophages to alleviate pulmonary fibrosis

BACKGROUND

Idiopathic Pulmonary Fibrosis (IPF) is a type of interstitial lung disease characterized by chronic inflammation due to persistent lung damage. Mesenchymal stem cells (MSCs), including those derived from the umbilical cord (UCMSCs) and placenta (PLMSCs), have been utilized in clinical trials for IPF treatment. However, the varying therapeutic effectiveness between these two MSC types remains unclear.

METHODS

In this study, we examined the therapeutic differences between UCMSCs and PLMSCs in treating lung damage using a bleomycin (BLM)-induced pulmonary injury mouse model.

RESULTS

We showed that UCMSCs had a superior therapeutic impact on lung damage compared to PLMSCs. Upon cytokine stimulation, UCMSCs expressed higher levels of inflammation-related genes and more effectively directed macrophage polarization towards the M2 phenotype than PLMSCs, both in vitro and in vivo. Furthermore, UCMSCs showed a preference for expressing CC motif ligation 2 (CCL2) and C-X-C motif chemokine ligand 1 (CXCL1) compared to PLMSCs. The expression of secreted phosphoprotein 1 (SPP1), triggering receptor expressed on myeloid cells 2 (Trem2), and CCAAT enhancer binding protein beta (Cebpb) in macrophages from mice with the disease treated with UCMSCs was significantly reduced compared to those treated with PLMSCs.

CONCLUSIONS

Therefore, UCMSCs demonstrated superior anti-fibrotic abilities in treating lung damage, potentially through inducing a more robust M2 polarization of macrophages than PLMSCs.

Manipulated mesenchymal stem cell therapy in the treatment of Parkinson's disease

Mesenchymal stem cell (MSC) therapy has been considered a promising approach for the treatment of Parkinson's disease (PD) for several years. PD is a globally prevalent neurodegenerative disease characterized by the accumulation of Lewy bodies and the loss of dopaminergic neurons, leading to severe motor and non-motor complications in patients. As current treatments are unable to halt the progression of neuronal loss and dopamine degradation, MSC therapy has emerged as a highly promising strategy for PD treatment. This promise is due to MSCs' unique properties compared to other types of stem cells, including self-renewal, differentiation potential, immune privilege, secretion of neurotrophic factors, ability to improve damaged tissue, modulation of the immune system, and lack of ethical concerns. MSCs have been employed in numerous pre-clinical and clinical studies for PD treatment with promising results. However, certain aspects of their efficacy in treating PD may benefit from various genetic and epigenetic modifications. In this review article, we assess these approaches to improving MSCs for specialized treatment of PD.

Hemodynamic effects of slower versus faster intravenous fluid bolus rates in critically ill patients: An observational study

PURPOSE

We compared the immediate and sustained effects of 500 mL of crystalloid administered at slow (333 mL/h) versus fast rates (999 mL/h) on mean arterial pressure (MAP) in critically ill patients.

MATERIALS AND METHODS

Hemodynamic variables were collected immediately before and every 30 min up to 60 min after the end of the infusion. The primary outcome was the adjusted difference in MAP.

RESULTS

We included 146 patients (slow rate: 71, fast rate: 75). One hour after the end of the infusion, there was no difference in the overall mean marginal effect on MAP between the groups [1.9 mmHg (95 % CI: -1.5 to 5.3 mmHg), p = 0.27] or on the perfusion parameters. Similarly, no difference was found in the immediate effect after 90 min [overall marginal effect: 1.1 mmHg (95 % CI: -2.3 to 4.6 mmHg); p = 0.52]. In patients with cardiac output (CO) monitoring, there was an increase in CO in the fast rate group (overall mean marginal effect: 1.78 L/min (95 % CI: 0.08 to 3.48 L/min); p = 0.04).

CONCLUSION

In critically ill patients, crystalloid infusion at both fast and slow rates did not lead to immediate or sustained differences in MAP. However, fast infusion may result in a greater increase in CO.

Goal-directed fluid therapy on the postoperative complications of laparoscopic hepatobiliary or pancreatic surgery: An interventional comparative study

BACKGROUND

Intraoperative fluid balance significantly affects patients' outcomes. Goal-directed fluid therapy (GDFT) has reduced the incidence of major postoperative complications by 20% for 30 days after open abdominal surgery. Little is known about GDFT during laparoscopic surgery.

AIM

We investigated whether GDFT affects the postoperative outcomes in laparoscopic hepatobiliary or pancreatic surgery compared with conventional fluid management.

METHODS

This interventional comparative study with a historical control group was performed in the tertiary care center. Patients were allocated to one of two groups. The GDFT (n = 147) was recruited prospectively and the conventional group (n = 228) retrospectively. In the GDFT group, fluid management was guided by the stroke volume (SV) and cardiac index (CI), whereas it had been performed based on vital signs in the conventional group. Propensity score (PS) matching was performed to reduce selection bias (n = 147 in each group). Postoperative complications were evaluated as primary outcome measures.

RESULTS

The amount of crystalloid used during surgery was less in the GDFT group than in the conventional group (5.1 ± 1.1 vs 6.3 ± 1.8 ml/kg/h, respectively; P <0.001), whereas the amount of colloid was comparable between the two groups. The overall proportion of patients who experienced any adverse events was 57.8% in the GDFT group and 70.1% in the conventional group (P = 0.038), of which the occurrence of pleural effusion was significantly lower in the GDFT group than in the conventional group (9.5% vs. 19.7%; P = 0.024). During the postoperative period, the proportion of patients admitted to the intensive care unit (ICU) was lower in the GDFT group than that in the conventional group after PS matching (4.1% vs 10.2%; P = 0.049).

CONCLUSIONS

GDFT based on SV and CI resulted in a lower net fluid balance than conventional fluid therapy. The overall complication rate in laparoscopic hepatobiliary or pancreatic surgery decreased after GDFT, and the frequency of pleural effusion was the most affected.

Efficacy and safety of a non-immersive virtual reality-based neuropsychological intervention for cognitive stimulation and relaxation in patients with critical illness: study protocol of a randomized clinical trial (RGS-ICU)

BACKGROUND

Experiencing a critical illness may be a stressful life event that is also associated with cognitive dysfunction during and after the intensive care unit (ICU) stay. A deep-tech solution based on non-immersive virtual reality, gamification and motion capture called Rehabilitation Gaming System for Intensive Care Units (RGS-ICU) has been developed that includes both cognitive stimulation and relaxation protocols specifically designed for patients with critical illness. This study aims to evaluate whether the cognitive and relaxation protocols of the RGS-ICU platform are 1) effective in improving neuropsychological outcomes during and after ICU stay and 2) safe for patients with critical illness.

METHODS

This is a study protocol for a multicenter longitudinal randomized clinical trial. At least 80 patients with critical illness will be included: 40 experimental subjects and 40 control subjects. Patients in the experimental group will receive daily 20-min sessions of cognitive stimulation and relaxation with the RGS-ICU platform adjuvant to standard ICU care in their own rooms during the ICU stay and until discharge from the ICU or up to a maximum of 28 days after randomization, provided they are alert and calm. Patients in the experimental group will be constantly monitored as part of standard ICU care to ensure the safety of the intervention and that no avoidable adverse events occur. Patients in the control group will receive standard ICU care. The primary outcome is objective cognition 12 months after ICU discharge, assessed with a composite index including measures of attention, working memory, learning/memory, executive function and processing speed. The secondary outcome is the safety of the intervention, assessed by considering the number of sessions terminated early due to unsafe events in physiological parameters. Other outcomes are comfort experienced during the ICU stay, and subjective cognition, mental health (anxiety, depression and post-traumatic stress disorder), functionality and health-related quality of life 12 months after ICU discharge.

DISCUSSION

The expected results are 1) better neuropsychological outcomes during and after the ICU stay in patients in the experimental group compared to patients in the control group and 2) that the cognitive and relaxation protocols of the RGS-ICU platform are safe for patients with critical illness.

TRIAL REGISTRATION

Clinicaltrials.gov NCT06267911. Registered on February 20, 2024.

Tumor- and host-derived heparanase-2 (Hpa2) attenuates tumorigenicity: role of Hpa2 in macrophage polarization and BRD7 nuclear localization

Little attention was given to heparanase 2 (Hpa2) over the last two decades, possibly because it lacks a heparan sulfate (HS)-degrading activity typical of heparanase. Emerging results suggest, nonetheless, that Hpa2 plays a role in human pathologies, including cancer progression where it functions as a tumor suppressor. Here, we examined the role of Hpa2 in cervical carcinoma. We report that high levels of Hpa2 correlate with prolonged survival of cervical carcinoma patients. Strong staining intensity of Hpa2 also correlates with low tumor grade. Overexpression of Hpa2 in SiHa cervical carcinoma cells resulted in tumor xenografts that were two-fold smaller than control tumors. Interestingly, even smaller tumor xenografts were developed by SiHa cells overexpressing the Pro140Arg and Asn543Ile Hpa2 missense mutations that were identified in patients diagnosed with urofacial syndrome (UFS). Utilizing the Ras recruitment system, we identified bromodomain-containing protein 7 (BRD7) to interact with Hpa2 and found that both BRD7 and the Hpa2 mutants are translocated to the cell nucleus in tumors developed by the Pro140Arg and Asn543Ile Hpa2 mutants. Utilizing our newly developed conditional Hpa2-KO mice, we further show that Hpa2 plays a critical role in macrophage polarization; in the absence of Hpa2, macrophages are shifted towards pro-tumorigenic, M2 phenotype. Notably, implanting SiHa cervical carcinoma cells together with Hpa2-KO macrophages promoted tumor growth. These results support, and further expand, the notion that Hpa2 functions as a tumor suppressor, co-operating with another tumor suppressor, BRD7.

Novel Dynamic Organ Storage System Enhances Liver Graft Function in a Porcine Donation After Circulatory Death Model

Donation after circulatory death (DCD) livers face increased risks of critical complications when preserved with static cold storage (SCS). Although machine perfusion (MP) may mitigate these risks, its cost and logistical complexity limit widespread application. We developed the Dynamic Organ Storage System (DOSS), which delivers oxygenated perfusate at 10°C with minimal electrical power requirement and allows real-time effluent sampling in a portable cooler. In a porcine DCD model, livers were preserved using DOSS or SCS for 10 hours and evaluated with 4 hours of normothermic MP, with n = 5 per group. After 4 hours of normothermic MP, the DOSS group demonstrated significantly lower perfusate lactate (p = 0.023), increased perfusate fibrinogen (p = 0.005), higher oxygen consumption (p = 0.018), greater bile production (p = 0.013), higher bile bicarbonate levels (p = 0.035) and bile/perfusate sodium ratio (p = 0.002), and lower hepatic arterial resistance after phenylephrine administration (p = 0.018). Histological analysis showed lower apoptotic markers in DOSS-preserved livers, with fewer cleaved caspase-3 (p = 0.039) and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL; p = 0.009) positive cells. These findings suggest that DOSS can enhance DCD allograft function during transport, offering potential clinical benefits and contributing to the expansion of the donor pool.

Comprehensive review of drug resistance in mammalian cancer stem cells: implications for cancer therapy

Cancer remains a significant global challenge, and despite the numerous strategies developed to advance cancer therapy, an effective cure for metastatic cancer remains elusive. A major hurdle in treatment success is the ability of cancer cells, particularly cancer stem cells (CSCs), to resist therapy. These CSCs possess unique abilities, including self-renewal, differentiation, and repair, which drive tumor progression and chemotherapy resistance. The resilience of CSCs is linked to certain signaling pathways. Tumors with pathway-dependent CSCs often develop genetic resistance, whereas those with pathway-independent CSCs undergo epigenetic changes that affect gene regulation. CSCs can evade cytotoxic drugs, radiation, and apoptosis by increasing drug efflux transporter activity and activating survival mechanisms. Future research should prioritize the identification of new biomarkers and signaling molecules to better understand drug resistance. The use of cutting-edge approaches, such as bioinformatics, genomics, proteomics, and nanotechnology, offers potential solutions to this challenge. Key strategies include developing targeted therapies, employing nanocarriers for precise drug delivery, and focusing on CSC-targeted pathways such as the Wnt, Notch, and Hedgehog pathways. Additionally, investigating multitarget inhibitors, immunotherapy, and nanodrug delivery systems is critical for overcoming drug resistance in cancer cells.

Portal vein pulsatility is associated with the cumulative fluid balance: A post hoc longitudinal analysis of a prospective, general intensive care unit cohort

BACKGROUND

Previous studies have explored tools for evaluating the effects of positive fluid balance, with recent emphasis, and controversies, on venous ultrasound parameters and composite scores. The portal vein pulsatility index and the renal venous pattern have emerged as the most promising indicators of volume-induced venous congestion. But in the general intensive care unit (ICU), numerous factors influence cardiovascular homeostasis, affecting venous function.

OBJECTIVES

This study aimed to evaluate the factors associated with portal vein pulsatility index in general ICU patients. Secondary objectives were to examine the correlations between pulsatility index and additional markers of congestion.

DESIGN

This exploratory study was a post hoc analysis of a prospective, multicentric, observational database.

SETTING

The data collection was performed in four ICUs in university-affiliated or tertiary hospitals.

PATIENTS

This study included adult patients within 24 h of general ICU admission with an expected ICU length of stay of more than 2 days.

INTERVENTION

Patients underwent clinical, biological, and echocardiographic assessments at several times: ICU admission, day 1, day 2, day 5 and the last day of ICU.

MAIN OUTCOME MEASURE

The study primary endpoint was the portal vein pulsatility index during the course of the patients' stay on the ICU.

RESULTS

One hundred forty-five patients and 514 haemodynamic evaluations were analysed. The mean age of the patients was 64 ± 15 years, 41% were women, with a median [IQR] admission simplified acute physiology score II of 46 [37 to 59]. The univariable followed by multivariable mixed-effects linear regression analyses demonstrated an association between portal vein pulsatility index, heart rate [estimate -0.002 (95% CI, -0.003 to -0.001), P < 0.001] and the cumulative fluid balance [estimate 0.0007 (95% CI, 0.00007 to 0.001), P = 0.024]. Portal vein pulsatility index showed no agreement with CVP of at least 12 mmHg (kappa correlation -0.008, P = 0.811), negative passive leg raising (kappa correlation -0.036, P = 0.430), mean inferior vena caval (IVC) diameter greater than 2 cm (kappa correlation -0.090, P = 0.025), maximal IVC diameter greater than 2 cm (kappa correlation -0.010, P = 0.835), hepatic vein systolic/diastolic ratio less than 1 (kappa correlation 0.043, P = 0.276), or renal vein pulsatile pattern (kappa correlation -0.243, P < 0.001).

CONCLUSION

The study findings emphasise the unique sensitivity of portal vein pulsatility index in assessing fluid balance in general ICU patients. The lack of correlation between portal vein pulsatility index and other parameters of venous congestion underscores its potential to provide distinctive insights into venous congestion.

Closed-Loop Automated Control System of Extracorporeal Membrane Oxygenation and Left Ventricular Assist Device Support in Cardiogenic Shock

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) benefits patients with cardiogenic shock (CS) but can increase left ventricular afterload and exacerbate pulmonary edema. Adding a percutaneous left ventricular assist device (LVAD) to VA-ECMO can optimize the hemodynamics. Because managing VA-ECMO and LVAD simultaneously is complex and labor-intensive, we developed a closed-loop automated control system for VA-ECMO and LVAD. Based on the circulatory equilibrium framework, this system automatically adjusts VA-ECMO and LVAD flows and cardiovascular drug and fluid dosages to achieve target arterial pressure (AP, 70 mm Hg), left atrial pressure (PLA, 14 mm Hg), and total systemic flow (Ftotal, 120-140 ml/min/kg). In seven anesthetized dogs with CS, VA-ECMO significantly increased AP and PLA from 24 (23-27) to 71 (63-77) mm Hg and 20.1 (16.3-22.1) to 43.0 (25.7-51.4) mm Hg, respectively. Upon system activation, PLA was promptly reduced. At 60 min postactivation, the system-controlled AP to 69 (65-74) mm Hg, PLA to 12.5 (12.0-13.4) mm Hg, and Ftotal to 117 (114-132) ml/min/kg while adjusting VA-ECMO flow to 59 (12-60) ml/min/kg, LVAD flow to 68 (54-78) ml/min/kg, and cardiovascular drug and fluid dosages. This system automatically optimizes VA-ECMO and LVAD hemodynamics, making it an attractive tool for rescuing patients with CS.

β-Cyclodextrin and cucurbit[7]uril as protective encapsulation agents of the CO-releasing molecule [CpMo(CO)3Me]

The CO releasing ability of the complex [CpMo(CO)3Me] (1) (Cp = η5-C5H5) has been assessed using a deoxymyoglobin-carbonmonoxymyoglobin assay. In the dark, CO release was shown to be promoted by the reducing agent sodium dithionite in a concentration-dependent manner. At lower dithionite concentrations, where dithionite-induced CO release was minimised, irradiation at 365 nm with a low-power UV lamp resulted in a strongly enhanced release of CO (half-life (t1/2) = 6.3 min), thus establishing complex 1 as a photochemically activated CO-releasing molecule. To modify the CO release behaviour of the tricarbonyl complex, the possibility of obtaining inclusion complexes between 1 and β-cyclodextrin (βCD) or cucurbit[7]uril (CB7) by liquid-liquid interfacial precipitation (1@βCD(IP)), liquid antisolvent precipitation (1@CB7), and mechanochemical ball-milling (1@βCD(BM)) was evaluated. All these methods led to the isolation of a true inclusion compound (albeit mixed with nonincluded 1 for 1@βCD(BM)), as evidenced by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), FT-IR and FT-Raman spectroscopies, and 13C{1H} magic angle spinning (MAS) NMR. PXRD showed that 1@βCD(IP) was microcrystalline with a channel-type crystal packing structure. High resolution mass spectrometry studies revealed the formation of aqueous phase 1 : 1 complexes between 1 and CB7. For 1@βCD(IP) and 1@CB7, the protective effects of the hosts led to a decrease in the CO release rates with respect to nonincluded 1. βCD had the strongest effect, with a ca. 10-fold increase in t1/4 for dithionite-induced CO release, and a ca. 2-fold increase in t1/2 for photoinduced CO release.

Exploration of simultaneous transients between cerebral hemodynamics and the autonomic nervous system using windowed time-lagged cross-correlation matrices: a CENTER-TBI study

BACKGROUND

Traumatic brain injury (TBI) can significantly disrupt autonomic nervous system (ANS) regulation, increasing the risk for secondary complications, hemodynamic instability, and adverse outcome. This retrospective study evaluated windowed time-lagged cross-correlation (WTLCC) matrices for describing cerebral hemodynamics-ANS interactions to predict outcome, enabling identifying high-risk patients who may benefit from enhanced monitoring to prevent complications.

METHODS

The first experiment aimed to predict short-term outcome using WTLCC-based convolution neural network models on the Wroclaw University Hospital (WUH) database (Ptraining = 31 with 1,079 matrices, Pval = 16 with 573 matrices). The second experiment predicted long-term outcome, training on the CENTER-TBI database (Ptraining = 100 with 17,062 matrices) and validating on WUH (Pval = 47 with 6,220 matrices). Cerebral hemodynamics was characterized using intracranial pressure (ICP), cerebral perfusion pressure (CPP), pressure reactivity index (PRx), while ANS metrics included low-to-high-frequency heart rate variability (LF/HF) and baroreflex sensitivity (BRS) over 72 h. Short-term outcome at WUH was assessed using the Glasgow Outcome Scale (GOS) at discharge. Long-term outcome was evaluated at 3 months at WUH and 6 months at CENTER-TBI using GOS and GOS-Extended, respectively. The XGBoost model was used to compare performance of WTLCC-based model and averaged neuromonitoring parameters, adjusted for age, Glasgow Coma Scale, major extracranial injury, and pupil reactivity in outcome prediction.

RESULTS

For short-term outcome prediction, the best-performing WTLCC-based model used ICP-LF/HF matrices. It had an area under the curve (AUC) of 0.80, vs. 0.71 for averages of ANS and cerebral hemodynamics metrics, adjusted for clinical metadata. For long-term outcome prediction, the best-score WTLCC-based model used ICP-LF/HF matrices. It had an AUC of 0.63, vs. 0.66 for adjusted neuromonitoring parameters.

CONCLUSIONS

Among all neuromonitoring parameters, ICP and LF/HF signals were the most effective in generating the WTLCC matrices. WTLCC-based model outperformed adjusted neuromonitoring parameters in short-term but had moderate utility in long-term outcome prediction.

Dietary prevention of antibiotic-induced dysbiosis and mortality upon aging in mice

Oral antibiotic use is both widespread and frequent in older adults and has been linked to dysbiosis of the gut microbiota, enteric infection, and chronic diseases. Diet and nutrients, particularly prebiotics, may modify the susceptibility of the gut microbiome to antibiotic-induced dysbiosis. We fed 12-month-old mice a high glycemic (HG) or low glycemic (LG) diet with or without antibiotics (ampicillin and neomycin) for an additional 11 months. The glycemic index was modulated by the ratio of rapidly digested amylopectin starch to slowly digested amylose, a type-2-resistant starch. We observed a significant decrease in survival of mice fed a HG diet containing antibiotics (HGAbx) relative to those fed a LG diet containing antibiotics (LGAbx). HGAbx mice died with an enlarged and hemorrhagic cecum, which is associated with colonic hyperplasia and goblet cell depletion. Gut microbiome analysis revealed a pronounced expansion of Proteobacteria and a near-complete loss of Bacteroidota and Firmicutes commensal bacteria in HGAbx, whereas the LGAbx group maintained a population of Bacteroides and more closely resembled the LG microbiome. The predicted functional capacity for bile salt hydrolase activity was lost in HGAbx mice but retained in LGAbx mice. An LG diet containing amylose may therefore be a potential therapeutic to prevent antibiotic-induced dysbiosis and morbidity.

Impact of macrohemodynamic manipulations during cardiopulmonary bypass on finger microcirculation assessed by photoplethysmography signal components

Objective.Continuous monitoring of the hemodynamic coherence between macro and microcirculation is difficult at the bedside. We tested the role of photoplethysmography (PPG) to real-time assessment of microcirculation during extreme manipulation of macrohemodynamics induced by the cardiopulmonary bypass (CPB).Approach.We analyzed the alternating (AC) and direct (DC) components of the finger PPG in 12 patients undergoing cardiac surgery with CPB at five moments: (1) before-CPB; (2) CPB-start, at the transition from pulsatile to non-pulsatile blood flow; (3) CPB-aortic clamping, at a sudden decrease in pump blood flow and volemia.; (4) CPB-weaning, during step-wise 20% decreases in pump blood flow and opposite proportional increases in native pulsatile blood flow; and (5) after-CPB.Main results.Nine Caucasian men and three women were included for analysis. Macrohemodynamic changes during CPB had an immediate impact on the PPG at all studied moments. Before-CPB the AC signal amplitude showed a median and IQR values of 0.0023(0.0013). The AC signal completely disappeared at CPB-start and at CPB-aortic clamping. During CPB weaning its amplitude progressively increased but remained lower than before CPB, at 80% [0.0008 (0.0005);p< 0.001], 60% [0.0010(0.0006);p< 0.001], and 40% [0.0013(0.0009);p= 0.011] of CPB flow. The AC amplitude returned close to Before-CPB values at 20% of CPB flow [0.0015(0.0008);p= 0.081], when CPB was completely stopped [0.0019 (0.0009);p= 0.348], and at after-CPB [0.0021(0.0009);p= 0.687]. The DC signal Before-CPB [0.95(0.02)] did not differ statistically from CPB-start, CPB-weaning and After-CPB. However, at CPB-aortic clamping, at no flow and a sudden drop in volemia, the DC signal decreased from [0.96(0.01)] to [0.94(0.02);p= 0.002].Significance.The macrohemodynamic alterations brought on by CPB were consistent with changes in the finger's microcirculation. PPG described local pulsatile blood flow (AC) as well as non-pulsatile blood flow and volemia (DC) in the finger. These findings provide plausibility to the use of PPG in ongoing hemodynamic coherence monitoring.

Chinese expert consensus on tunneled technique for peripherally inserted central venous catheters

OBJECTIVE

To formulate an expert consensus on an evidence-based overview of all topics related to the Tunneled Peripherally Inserted Central Venous Catheters.

METHODS

A Chinese consensus based on evidence has provided a definition and indications for Tunneled Peripherally Inserted Central Venous Catheters. The literature on Tunneled Peripherally Inserted Central Venous Catheter was reviewed from its inception to March 2024. The indications were developed using the RAND/UCLA Appropriateness Method.

RESULTS

This consensus presents five indications for Tunneled Peripherally Inserted Central Venous Catheters, covering tunneling definitions, key processes, tunneling devices, various applications, and maintenance. The indications aim to enhance patient safety and optimize the efficacy of tunneled peripherally inserted central venous catheters.

CONCLUSIONS

This consensus is based on critical evidence review and the clinical experts aimed to assist clinicians in applying tunneling techniques. Further prospective studies are needed to evaluate the impact of complications related to the tunneling technique.

Prognostic Factors Associated With Intracranial Hemorrhage and Ischemic Stroke During Venovenous Extracorporeal Membrane Oxygenation: A Systematic Review

OBJECTIVES

Venovenous extracorporeal membrane oxygenation (ECMO) is a life-preserving intervention for patients with respiratory failure refractory to conventional mechanical ventilation. Intracranial hemorrhage (ICH) and ischemic stroke are life-threatening complications associated with venovenous ECMO. Despite this, little is known regarding the prognostic factors associated with these adverse neurologic events. We conducted a systematic review that characterizes these predictors of ICH and ischemic stroke during venovenous ECMO.

DATA SOURCES

We conducted a comprehensive search of MEDLINE and Embase via the Ovid interface.

STUDY SELECTION

We developed and performed a literature search to identify articles that evaluated ICH and ischemic stroke in adult patients undergoing venovenous ECMO. We excluded studies based on design, target population, and outcomes.

DATA EXTRACTION

Data were extracted manually by one reviewer. Risk of bias assessment was completed using the Quality in Prognostic Studies approach for each included study. Prognostic factors associated with ICH and ischemic stroke that were identified in two or more included studies were evaluated through the Grading of Recommendations, Assessment, Development, and Evaluation approach.

DATA SYNTHESIS

Three hundred thirty-three studies met criteria for screening. Seventeen studies met final inclusion criteria. Seventeen studies addressed predictors of ICH. Five studies demonstrated an increased risk of ICH with lower pH before venovenous ECMO (moderate certainty). Five studies demonstrated an increased risk of ICH with greater decreases in Paco2 pre- to post-venovenous ECMO cannulation (moderate certainty). Four studies addressed predictors of ischemic stroke; however, there were no predictors of ischemic stroke identified in two or more of the included studies.

CONCLUSIONS

This systematic review demonstrates that abnormalities and changes in blood gas parameters from pre- to post-venovenous ECMO cannulation are probably associated with increased risk of ICH. Additional high-quality studies dedicated to probable predictors of these adverse neurologic events are crucial to understanding the pathophysiology of ICH and ischemic stroke in this population and informing clinical practice to mitigate the risk of these life-threatening events.

Predictors of VILI risk: driving pressure, 4DPRR and mechanical power ratio-an experimental study

BACKGROUND

Ventilator-induced lung injury (VILI) is one of the side effects of mechanical ventilation during ARDS; a prerequisite for averting it is the quantification of its risk factors associated with a given ventilatory setting. Many clinical variables have been proposed as predictors of VILI, of which driving pressure is the most widely used. In this study, we compared the performance of driving pressure, four times the driving pressure added to respiratory rate (4DPRR) and mechanical power ratio.

RESULTS

In a study population of 121 previously healthy pigs exposed to harmful ventilation, we compared the association of driving pressure, 4DPRR and mechanical power ratio to lung weight, lung wet-to-dry and total histological score. All the three variables were associated with these outcomes. Driving pressure, 4DPRR and mechanical power ratio increase linearly with the lung weight (adjusted R2 of 0.27, 0.36 and 0.40, respectively), the lung wet-to-dry ratio (adjusted R2 of 0.19, 0.25 and 0.37) and the total histological score (adjusted R2 of 0.26, 0.38 and 0.26). Using a multiple linear regression model with forward analysis, starting with tidal volume and progressively adding respiratory rate and positive end-expiratory pressure, and comparing the topic with the outcome variables, we obtained R2 values, respectively, of 0.07, 0.20, 0.42 for lung weight, 0.09, 0.19, 0.26 for lung wet-to-dry ratio and 0.07, 0.27, 0.43 for total histological score.

CONCLUSIONS

Driving pressure, 4DPRR and mechanical power ratio, were all associated with lung injury in healthy animals undergoing mechanical ventilation.

The Role of High Density Lipoproteins in Sepsis

High density lipoproteins (HDL) are best known for their role in atherosclerotic cardiovascular diseases. However, efforts to reduce cardiovascular risk by increasing the concentration of cholesterol in HDL have failed, raising the question of whether HDL may have other, more central aspects to its role in health and disease. In epidemiological studies, low levels of HDL cholesterol are strongly associated with risk of infectious diseases and death from sepsis, and during sepsis a larger decline in HDL cholesterol predicts a worse outcome. Many preclinical studies have examined strategies to augment HDL genetically or pharmacologically, and have shown that this leads to protection from sepsis in animal models. Data in humans are more limited, but suggest a clinically-relevant role of HDL in mediating the response to pathogen-associated lipids and preventing excessive inflammation. Collectively, these data raise the intriguing possibility that a clinically important biological function of HDL is as a component of the innate immune system, and suggest that pharmacological manipulation of HDL may be a strategy to reduce the organ dysfunction and death that results from uncontrolled inflammation during sepsis. In this review article, we discuss recent advances in our understanding of the role of HDL in sepsis.

Substrate utilization of carbohydrates, fat, and protein in the late acute phase of critically ill surgical patients: A retrospective longitudinal study

BACKGROUND AND AIMS

Tailoring nutrition to measured energy expenditure (EE) and provision of adequate protein amounts, is considered gold standard for critically ill patients. There are currently no recommendations to measure specific substrate utilization or to adapt nutrition accordingly.

METHODS

In this retrospective longitudinal study, we analyzed results of 316 simultaneous measurements of indirect calorimetry (IC) and urinary urea nitrogen (UUN) in 191 mechanically ventilated, critically ill patients, admitted to the surgical intensive care unit (SICU) in a tertiary medical center. We calculated substrate utilization, compared it to administered nutrition, investigated factors that may influence it and tested the added value of routine UUN measurements over IC alone.

RESULTS

The mean total EE, measured using the indirect calorimetry module, was 1600 ± 451 kcal/day The mean daily fat, carbohydrates and protein oxidation were 118.3 ± 63.9 g, 53.3 ± 114.1 g and 64.7 ± 36.0 g, respectively, accounting for 68.8 % ± 31.4 %, 14.2 % ± 29.6 % and 17.0 % ± 8.6 % of the total EE. Fasting and noradrenaline administration were the only factors that influenced substrate utilization, resulting in higher fat and lower carbohydrate utilization (p < 0.045 for all). There were significant differences between percentage of substrate utilization and supply, with average differences of +28.5 % for fat, -38 % for carbohydrates and +1.9 % for protein (p < 0.006 for all).

CONCLUSIONS

SICU patients demonstrated very high fat utilization and lower than expected carbohydrate utilization, that differed significantly from amounts supplied. Further prospective studies are needed to elucidate the clinical impact of these findings.

Oleaginous Yeast Biology Elucidated With Comparative Transcriptomics

Extremophilic yeasts have favorable metabolic and tolerance traits for biomanufacturing- like lipid biosynthesis, flavinogenesis, and halotolerance - yet the connection between these favorable phenotypes and strain genotype is not well understood. To this end, this study compares the phenotypes and gene expression patterns of biotechnologically relevant yeasts Yarrowia lipolytica, Debaryomyces hansenii, and Debaryomyces subglobosus grown under nitrogen starvation, iron starvation, and salt stress. To analyze the large data set across species and conditions, two approaches were used: a "network-first" approach where a generalized metabolic network serves as a scaffold for mapping genes and a "cluster-first" approach where unsupervised machine learning co-expression analysis clusters genes. Both approaches provide insight into strain behavior. The network-first approach corroborates that Yarrowia upregulates lipid biosynthesis during nitrogen starvation and provides new evidence that riboflavin overproduction in Debaryomyces yeasts is overflow metabolism that is routed to flavin cofactor production under salt stress. The cluster-first approach does not rely on annotation; therefore, the coexpression analysis can identify known and novel genes involved in stress responses, mainly transcription factors and transporters. Therefore, this work links the genotype to the phenotype of biotechnologically relevant yeasts and demonstrates the utility of complementary computational approaches to gain insight from transcriptomics data across species and conditions.

A Scoping Review of End-of-Life Discussions and Palliative Care: Implications for Neurological Intensive Care in Latin America and the Caribbean

Background: Palliative care (PC) is essential to improve quality of life for individuals with life-limiting acute neurological conditions, particularly in resource-limited settings. In Latin America and the Caribbean (LAC), there is limited health care professional training and education on PC. Objective: We reviewed the peer-reviewed literature discussing end-of-life care, withdrawal of life-sustaining treatments (WOLST), and PC in the acute inpatient setting. Methods: We searched 10 databases, including peer-reviewed published conference abstracts and articles published until May 22, 2024, and included literature describing goals-of-care discussions or availability of PC services in an inpatient setting in LAC countries. Results: We identified 34 articles that highlighted end-of-life discussions, WOLST, and PC utilization in inpatient settings in LAC. We identified several themes across literature as follows: limitations to PC referrals, hospice/end-of-life care, and the role of advanced directives in LAC. Our review found that several articles highlight the limitations of PC usage in LAC and inadequate access to treatments, including gastrostomy and tracheostomy tube placement. Conclusions: Our review demonstrates a need to improve PC knowledge and access to end-of-life care resources. Regional educational efforts are needed to improve PC knowledge among health care providers who care for patients with acute neurological conditions in LAC.

Predictive validity of interleukin 6 (IL-6) for the mortality in critically ill COVID-19 patients with the B.1.617.2 (Delta) variant in Vietnam: a single-centre, cross-sectional study

OBJECTIVES

To investigate the serum IL-6 levels and their rate of change in predicting the mortality of critically ill patients with COVID-19 in Vietnam.

DESIGN

A single-centre, cross-sectional study.

SETTING

An Intensive Care Centre for the Treatment of Critically Ill Patients with COVID-19 in Ho Chi Minh City, Vietnam.

PARTICIPANTS

We included patients aged 18 years or older who were critically ill with COVID-19 and presented to the study centre from 30 July 2021 to 15 October 2021. We excluded patients who did not have serum IL-6 measurements between admission and the end of the first day.

PRIMARY OUTCOME MEASURES

The primary outcome was hospital all-cause mortality.

RESULTS

Of 90 patients, 41.1% were men, the median age was 60.5 years (Q1-Q3: 52.0-71.0), and 76.7% of patients died in the hospital. Elevated IL-6 levels were observed on admission (41.79 pg/mL; Q1-Q3: 20.68-106.27) and on the third day after admission (72.00 pg/mL; Q1-Q3: 26.98-186.50), along with a significant rate of change in IL-6 during that period (839.5%; SD: 2753.2). While admission IL-6 level (areas under the receiver operator characteristic curve (AUROC): 0.610 (95% CI: 0.459 to 0.761); cut-off value ≥15.8 pg/mL) and rate of change in IL-6 on the third day of admission (AUROC: 0.586 (95% CI: 0.420 to 0.751); cut-off value ≥-58.7%) demonstrated poor discriminatory ability in predicting hospital mortality, the third day IL-6 rate of change from admission ≥-58.7% (adjusted OR: 12.812; 95% CI: 2.104 to 78.005) emerged as an independent predictor of hospital mortality.

CONCLUSIONS

This study focused on a highly selected cohort of critically ill COVID-19 patients with a high IL-6 level and mortality rate. Despite the poor discriminatory value of admission IL-6 levels, the rate of change in IL-6 proved valuable in predicting mortality. To identify critically ill COVID-19 patients with the highest risk for mortality, monitoring the serial serum IL-6 measurements and observing the rate of change in serum IL-6 levels over time are needed.

Beyond conventional care: The therapeutic potential of hemoperfusion in severe COVID-19

BACKGROUND

Hemoperfusion (HP) is an extracorporeal blood purification modality utilized to remove small- to medium-sized molecules, such as toxins and cytokines, that are difficult to remove by conventional hemodialysis. In clinical practice, HP has been successfully used as a salvage therapy for drug overdose and occasionally in patients with liver failure and sepsis.

AIM

To summarize the clinical outcomes of a series of patients with severe coronavirus disease 2019 (COVID-19) who received HP.

METHODS

Here, we summarize the clinical outcomes of a series of 18 patients with severe COVID-19 who received HP in our institution during the COVID-19 pandemic. A review of the literature was also performed.

RESULTS

HP was well-tolerated, and after an average of three sessions, respiratory and cardiovascular parameters as well as blood inflammatory markers improved in most patients. Ten patients were discharged alive. Our literature search identified a total of 20 studies (873 patients) in which HP was used for COVID-19. Nine studies reported improvements in respiratory parameters, and 13 studies (438 patients in total) reported better survival rates in patients undergoing HP.

CONCLUSION

HP was well-tolerated in patients with severe COVID-19, and most studies reported improved clinical parameters, including better survival rates, when HP was used in patients with severe COVID-19. Further research, especially prospective studies, is needed to evaluate the utility of HP as an early and supportive therapy for critically ill patients due to infectious diseases, such as those with COVID-19 or severe sepsis.

In Vitro Comparison of Inspiration-Synchronized and Continuous Vibrating Mesh Nebulizer During Adult Invasive Mechanical Ventilation

Background: Aerosol delivery may be enhanced by utilizing an inspiration-synchronized nebulization mode, where nebulization occurs only during inspiration. This study aimed to compare aerosol delivery of albuterol via a prototype of an inspiration-synchronized vibrating mesh nebulizer (VMN) versus continuous VMN during invasive mechanical ventilation. Methods: A critical care ventilator equipped with a heated-wire circuit to deliver adult parameters was attached to an endotracheal tube (ETT), a collection filter, and a test lung. The nebulizer was placed at the humidifier's inlet, inspiratory limb at the Y-piece, and between the Y-piece and ETT. Conventional VMNs producing standard size aerosol particles (Solo; Aerogen Ltd) were compared with prototype small-particle VMNs (Aerogen Pharma) in both inspiration-synchronization and continuous modes. In each run, 1 mL of albuterol (2.5 mg) was used (n = 5). The drug was eluted from the collection filter and assayed with UV spectrophotometry (276 nm). Results: The inhaled dose with inspiration-synchronization mode was 1.4 to 3.6 times that with the continuous mode, regardless of nebulizer positions (all p < 0.001). The small-particle VMN delivered an 8%-69% greater inhaled dose than the conventional VMN (Solo), regardless of the nebulizer placement or aerosol generation mode (all p < 0.001). The highest inhaled dose (50%-60%) with the inspiration-synchronized VMN was observed when it was placed at the ETT (all p < 0.001), whereas the continuous VMN performed better when positioned near the humidifier, with an inhaled dose of 21%-37% (p < 0.001). Conclusion: The inspiration-synchronized VMN delivered a greater inhaled dose than continuous VMN, irrespective of nebulizer placement. The prototype VMN producing smaller aerosol particles resulted in a greater inhaled dose than the conventional VMN (Solo), regardless of placement or aerosol generation modes. The inspiration-synchronized VMN achieved the highest delivery when placed close to the airway, whereas the continuous VMN delivered the most when positioned near the ventilator.

How to minimize mechanical power during controlled mechanical ventilation

High intrapulmonary pressures, large tidal volumes, and elevated respiratory rates during controlled mechanical ventilation can lead to barotrauma, volutrauma, and atelectrauma. Mechanical power-defined as the product of the pressure-volume integral and respiratory rate-consolidates these three risk factors into a single, intuitive parameter. Several studies have demonstrated that higher mechanical power correlates with an increased risk of lung injury and mortality, prompting the suggestion that mechanical power should be minimized. However, under the constraint of maintaining a fixed alveolar minute ventilation and positive end-expiratory pressure (PEEP), it remains unclear how to adjust respiratory rate and tidal volume to minimize mechanical power. This study provides an analytical solution to this optimization problem. Accordingly, only the elastic component of mechanical power should be targeted for minimization. Regardless of lung elastance or resistance, or the mode and settings of the ventilator, the elastic power is minimized at a tidal volume equal to twice the anatomic dead space, or approximately 4.4 ml/kg of body weight.

Combining Medication With High-Intensity-Focused Ultrasound for Adenomyosis: A Network Meta-Analysis of Randomized Controlled Trials

This network meta-analysis aims to identify the best possible combination therapy for individuals suffering from adenomyosis. To identify pertinent research for the network meta-analysis, a comprehensive search was conducted across multiple databases, including PubMed, Embase, Cochrane Library, Web of Science, CNKI, WanFang, and VIP, spanning from their commencement to February 21, 2024. The study's focus was on evaluating outcomes including visual analog scale (VAS) scores for dysmenorrhea, measurements of uterine and lesion volumes, menstrual blood loss, and the rate of disease recurrence. The findings from both direct and indirect comparisons, which were quantitatively assessed using weighted mean differences or relative risk along with their respective 95% confidence intervals, were graphically depicted in forest plots. Additionally, the ranking probability was illustrated, which indicated the likelihood of various high-intensity-focused ultrasound (HIFU) combination therapies being the most effective across each measured outcome. In the final analysis, this network meta-analysis encompassed a total of 31 articles. The results showed that HIFU combined with gonadotropin-releasing hormone agonist (GnRH-a) and progestin was more effective to decrease VAS score for dysmenorrhea than other combined therapies. HIFU combined with progestin was superior to other combined therapies in decreasing uterine volume, lesion size, and recurrence rate. HIFU combined with mifepristone was more effective to reduce menstrual volume compared to other combined therapies. The analysis suggests that regimens incorporating HIFU along with GnRH-a and progestin, or HIFU combined with progestin or HIFU combined with mifepristone might offer superior benefits in the clinical management of adenomyosis. These combined treatment approaches could potentially be more effective options for patients suffering from this condition.

Paracetamol metabolism by endothelial cells - Potential mechanism underlying intravenous paracetamol-induced hypotension

It was shown previously that a metabolite of acetaminophen (APAP), N-acetyl-p-benzoquinone imine (NAPQI), is a potent vasodilator, which could underlie the hypotension observed when APAP is administered intravenously. However, it is unknown whether APAP metabolism to NAPQI is possible in the vasculature. In this study, we examine the hypothesis that APAP is metabolized by cytochrome P450 enzymes within the endothelium, which may be accelerated in critically ill patients by the presence of elevated myeloperoxidase (MPO). Exposure of human coronary artery endothelial cells (HCAECs) to APAP resulted in the formation of protein-bound APAP adducts. Proteomic analysis of HCAECs exposed to APAP showed upregulation of CYP20A1, together with proteins involved in the pentose phosphate pathway and maintaining redox homeostasis. Proteomic analyses of mesenteric arteries from rats administered intravenous APAP are consistent with a key role of the vascular wall in APAP metabolism, with similar proteomic pathway changes identified in HCAECs. These changes occurred over a short timeframe and were not seen in the corresponding proteomic analyses of liver tissue. Intracellular thiols were depleted in HCAECs upon APAP treatment, which was partially attenuated by ketoconazole, consistent with the involvement of cytochrome P450 enzymes in the metabolism of APAP to a thiol-reactive metabolite such as NAPQI. Evidence was also obtained for the metabolism of APAP to a thiol-reactive intermediate by MPO in the absence of chloride ions, consistent with NAPQI formation. Taken together, these data provide a putative mechanism to explain the presentation of hypotension in critically ill patients following IV APAP administration.

Bedside Assessment of the Respiratory System During Invasive Mechanical Ventilation

Assessing the respiratory system of a patient receiving mechanical ventilation is complex. We provide an overview of an approach at the bedside underpinned by physiology. We discuss the importance of distinguishing between extensive and intensive ventilatory variables. We outline methods to evaluate both passive patients and those making spontaneous respiratory efforts during assisted ventilation. We believe a comprehensive assessment can influence setting mechanical ventilatory support to achieve lung and diaphragm protective ventilation.

Inhibiting triggering receptor expressed on myeloid cells 1 signaling to ameliorate skin fibrosis

Systemic sclerosis (SSc) is characterized by immune system failure, vascular insult, autoimmunity, and tissue fibrosis. TGF-β is a crucial mediator of persistent myofibroblast activation and aberrant extracellular matrix production in SSc. The factors responsible for this are unknown. By amplifying pattern recognition receptor signaling, triggering receptor expressed on myeloid cells 1 (TREM-1) is implicated in multiple inflammatory conditions. In this study, we used potentially novel ligand-independent TREM-1 inhibitors in preclinical models of fibrosis and explanted SSc skin fibroblasts in order to investigate the pathogenic role of TREM-1 in SSc. Selective pharmacological TREM-1 blockade prevented and reversed skin fibrosis induced by bleomycin in mice and mitigated constitutive collagen synthesis and myofibroblast features in SSc fibroblasts in vitro. Our results implicate aberrantly activated TREM-1 signaling in SSc pathogenesis, identify a unique approach to TREM-1 blockade, and suggest a potential therapeutic benefit for TREM-1 inhibition.