Traumatic inflammatory response: pathophysiological role and clinical value of cytokines

When to pursue acute rib fracture fixation

PURPOSE OF REVIEW

This review will explore acute rib fracture management focusing on indications and timing for acute surgical stabilization of rib fractures (SSRF).

RECENT FINDINGS

SSRF is a well tolerated and effective approach for a variety of rib fracture patterns and is most commonly used to correct either clinical flail chest or multiple displaced fractures. Objective tools that assess for deranged pulmonary dynamics may identify patients with other fracture patterns who will also benefit from SSRF. Multimodal analgesia approaches are essential regardless of whether SSRF is pursued; intractable pain may also prompt SSRF. Hemodynamic instability precludes acute SSRF. Otherwise, SSRF should occur within 72 h of injury. Preoperative planning includes thoracic computed tomography scanning, and a preanesthetic evaluation, especially in the geriatric patient based on the presence of comorbidities. Preoperative coordination with other services that also need to address acute injuries helps condense anesthesia exposures. Acute SSRF reduces pain and in particular pulmonary complications in those with acute rib fractures.

SUMMARY

SSRF is a well tolerated and effectively acutely deployed operative technique to address specific rib fracture injury patterns. It is ideally embraced as a structured program to facilitate collaboration, coordination, and program performance evaluation.

Neutrophils and COVID-19

Neutrophils are the first line of defense against pathogens, most effectively by forming Neutrophil Extracellular Traps (NETs). Neutrophiles are further classified into several subpopulations during their development, eliminating pathogens through various mechanisms. However, due to the chaotic and uncontrolled immune response, NETs are often severely resulting in tissue damage and lung infections. The uncontrolled and poorly acknowledged host response regarding the cytokine storm is one of the major causes of severe COVID-19 conditions. Specifically, the increased formation of low-density neutrophils (LDNs), together with neutrophil extracellular traps (NETs) is closely linked with the severity and poor prognosis in patients with COVID-19. In this review, we discuss in detail the ontogeny of neutrophils at different stages and their recruitment and activation after infections, focusing on SARS-CoV-2. In addition, this chapter summarized the research progress on potential targeted drugs (NETs and Cytokine inhibitors) for neutrophil medical therapy and hoped to provide reference for the development of related therapeutic drugs for critically ill COVID-19 patients.

Application prospect of polysaccharide in the development of vaccine adjuvants

Vaccination is an effective strategy for preventing infectious diseases. Subunit vaccines offer more precise targeting and safer protection compared with traditional inactivated virus vaccines. However, due to their poor immunogenicity, subunit vaccines necessitate the use of adjuvants to stimulate the immune system. Adjuvants have long been incorporated into vaccines to enhance the body's immune response, allowing for reduced dosage and lower production costs. Despite the development of numerous vaccine adjuvants, few exhibit the necessary potency and low toxicity for clinical use, often due to limited efficacy or adverse side effects. This underscores the urgent need for novel human vaccine adjuvants that are safe, effective, and cost-efficient. Recent studies have identified certain natural polysaccharides as promising human vaccine adjuvants due to their immunostimulatory properties, low toxicity, and high safety profiles, which enhance both humoral and cellular immunity. These natural polysaccharides are primarily derived from traditional Chinese medicine (TCM) plants, bacteria, and yeast. This review comprehensively analyzes several promising polysaccharide adjuvants, discussing their clinical applications, market potential, and immunoregulatory activities. In summary, the future prospects of polysaccharides provide valuable insights for the application and development of vaccine adjuvants.

The Impact of Non-trauma Factors on Trauma Patient Mortality and Hospital Resource Utilization: Population-Based Retrospective Review

BackgroundThe death of trauma patients with low injury severity scores (ISS) may not be fully explained by the severity of their injuries. Our objective was to evaluate preexisting conditions (PECs) that may contribute to the mortality rate of and hospital resources consumed by patients with low ISS.MethodsTrauma patients with ISS <9 were selected from the National Trauma Database Bank [NTDB] [2019-21]. Bivariate and multivariate analysis identified the risk factors associated with mortality, adjusting for secondary PECs, mechanism of injury, AIS body region, vital signs, and blood transfusion. A t test was used to compare PEC status with intensive care unit (ICU) and hospital length of stay (LOS) for significant differences (P < .05).Results1,689,392 patients suffered mild injuries [59.1% male, mean age 45.2, 8579 expired (0.5%)]. Mortality was associated with the presence of several risk factors, especially advanced directive [OR = 9.13, P < .001], cirrhosis [OR = 8.55, P < .001], disseminated cancer [OR = 8.53, P < .001], congestive heart failure (CHF) [OR = 6.62, P < .001], chronic renal failure (CRF) [OR = 6.16, P < .001], chemotherapy for cancer [OR = 5.64, P < .001], peripheral arterial disease (PAD) [OR = 5.32, P < .001], myocardial infarction (MI) [OR = 4.96, P < .001], dementia [OR = 4.62, P < .001], and functionally dependent health [OR = 4.57, P < .001]. In addition, there was a relationship between the presence of several PECs and increased ICU and hospital LOS, especially cirrhosis, CRF, CHF, and PAD.DiscussionNontraumatic factors and preexisting conditions are associated with increased mortality and hospital resource consumption in trauma patients with a low ISS. They should be considered during clinical decision-making for these patients, who may otherwise masquerade as part of a low-risk population.

Neurons Are Not All the Same: Diversity in Neuronal Populations and Their Intrinsic Responses to Spinal Cord Injury

Functional recovery following spinal cord injury will require the regeneration and repair of damaged neuronal pathways. It is well known that the tissue response to injury involves inflammation and the formation of a glial scar at the lesion site, which significantly impairs the capacity for neuronal regeneration and functional recovery. There are initial attempts by both supraspinal and intraspinal neurons to regenerate damaged axons, often influenced by the neighboring tissue pathology. Many experimental therapeutic strategies are targeted to further stimulate the initial axonal regrowth, with little consideration for the diversity of the affected neuronal populations. Notably, recent studies reveal that the neuronal response to injury is variable, based on multiple factors, including the location of the injury with respect to the neuronal cell bodies and the affected neuronal populations. New insights into regenerative mechanisms have shown that neurons are not homogenous but instead exhibit a wide array of diversity in their gene expression, physiology, and intrinsic responses to injury. Understanding this diverse intrinsic response is crucial, as complete functional recovery requires the successful coordinated regeneration and reorganization of various neuron pathways.

Haemodynamic management of septic shock

Septic shock is a significant challenge in the management of patients with burns and traumatic injuries when complicated by infection, necessitating prompt and effective haemodynamic support. This review provides a comprehensive overview of current strategies for vasopressor and fluid management in septic shock, with the aim to optimize patient outcomes. With regard to vasopressor management, we elaborate on the pharmacologic profiles and clinical applications of catecholamines, vasopressin derivatives, angiotensin II, and other vasoactive agents. Noradrenaline remains central to septic shock management. The addition of vasopressin, when sequentially added to noradrenaline, offers a non-catecholaminergic vasoactive effect with some clinical benefits and risks of adverse effects. Emerging agents such as angiotensin II and hydroxocobalamin are highlighted for their roles in catecholamine-resistant vasodilatory shock. Next, for fluid management, crystalloids are currently preferred for initial resuscitation, with balanced crystalloids showing benefits over saline. The application of albumin in septic shock warrants further research. High-quality evidence does not support large-volume fluid resuscitation, and an individualized strategy based on haemodynamic parameters, including lactate clearance and capillary refill time, is recommended. The existing knowledge suggests that early vasopressor initiation, particularly noradrenaline, may be critical in cases where fluid resuscitation takes inadequate effect. Management of refractory septic shock remains challenging, with novel agents like angiotensin II and methylene blue showing potential in recent studies. In conclusion, Further research is needed to optimize haemodynamic management of septic shock, particularly in developing novel vasopressor usage and fluid management approaches.

The IL-1β/STAT1 Axis inhibits STAT3 function via Sequestration of the transcriptional activator GLIS2, leading to postoperative vascular dysfunction

Surgery-induced endothelial dysfunction is crucial in thrombus formation, driven by the release of inflammatory mediators due to surgical trauma. The STAT family, known for amplifying inflammatory responses via cytokine activation, plays an unclear role in the signaling mechanisms from surgery to molecular activation, and their regulatory effects on inflammation vary. This study aimed to identify key signaling pathways responsible for vascular dysfunction post-surgery and to discover potential targets for predicting or preventing thrombosis. To explore this, endothelial cells were co-cultured with post-surgical trauma serum and analyzed using various assays. Bioinformatics analysis linked surgical trauma with pathways involving thrombosis, interleukins, cytokines, and STAT signaling. Elevated inflammatory mediators were observed in mouse serum post-surgical trauma, with IL-6 activating STAT3 to enhance endothelial proliferation, while IL-1β activated STAT1, inhibiting STAT3's effects. Gli-similar 2 (GLIS2), a novel coactivator of STAT3, was found to regulate STAT transcription. STAT1, however, inhibited GLIS2's interaction with STAT3, suppressing STAT3's role in endothelial proliferation. The study concludes that IL-1β-triggered STAT1 activation impedes GLIS2-STAT3 interaction, reducing STAT3's transcriptional activity and leading to endothelial dysfunction, presenting new targets for preventing post-surgical trauma endothelial dysfunction and thrombosis.

Hemogram-Based Phenotypes of the Immune Response and Coagulopathy in Blunt Thoracic Trauma

Background: Blunt thoracic trauma possesses unique physiopathological traits due to the complex interaction of immune and coagulation systems in the lung tissue. Hemogram-based ratios such as neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), neutrophil-to-lymphocyte × platelet (NLPR) ratios have been studied as proxies for immune dysregulation and survival in trauma. We hypothesized that blunt thoracic trauma patients exhibit distinct patterns of coagulation and inflammation abnormalities identifiable by the use of readily available hemogram-derived markers. Methods: The present study represents a retrospective observational analysis that included 86 patients with blunt thoracic trauma from a single high-volume level one trauma center. The primary outcome was mortality prediction in blunt thoracic trauma patients using these derived biomarkers. Secondary outcomes included phenotypes of the immune response and coagulopathy and the prediction of non-fatal adverse events. Results: A U-shaped distribution of mortality was found, with high rates of early deaths in patients with an NLPR value of <3.1 and high rates of late deaths in patients with NLPR > 9.5. A subgroup of blunt thoracic trauma patients expressing moderate inflammation and inflammation-induced hypercoagulation objectified as NLPR between 3.1 and 9.5 may have a survival benefit (p < 0.0001). The NLPR cut-off for predicting early deaths and the need for massive transfusion was 3.1 (sensitivity = 80.00% and specificity = 71.05%). Conclusions: These findings suggest that blunt thoracic trauma patients exhibit distinct phenotypes of the immune response and coagulopathy from the early stages. A controlled, balanced interaction of immune, coagulation, and fibrinolytic systems might effectively achieve tissue repair and increase survival in thoracic trauma patients and should be subject to further research.

Extracellular vesicles epitopes as potential biomarker candidates in patients with traumatic spinal cord injury

Background

Extracellular vesicles (EVs), a heterogeneous group of cell-derived, membrane-enclosed vesicles bearing cell-specific epitopes, have been demonstrated to play a crucial role in neuronal-glial communication and the orchestration of neuroinflammatory processes. However, the existing evidence regarding their function as biomarkers and their role in the pathobiology of traumatic spinal cord injuries (tSCI), particularly in humans, is scarce.

Objective

The primary goal of this study was to investigate whether a distinct pattern of EV surface epitopes detected in the plasma of individuals suffering from spinal cord injury is indicative of tSCI.

Methods

The study includes patients with isolated tSCI (n=8), polytrauma patients without tSCI (PT; ISS ≥16, n=8), and healthy volunteers (HV; n=8). Plasma samples from tSCI and PT patients were collected right after admission to the emergency room (ER), 24 hours (24h), and 48h after trauma. EVs were isolated via size exclusion chromatography, and EVs' surface epitopes were quantified with MACSPlex EV Kit Neuro (prototype product, Miltenyi Biotec) and compared among the groups. Additionally, results were correlated with clinical parameters.

Results

In total, 19 epitopes differed significantly between the tSCI and the HV groups. Out of these 19, four (CD47, CD56, CD68, and ADAM17) were found to differ significantly among tSCI and PT groups. The expression of the CD47 epitope was found to correlate positively with the American Spinal Injury Association (ASIA) impairment scale.

Conclusion

We identified four potential EV-based tSCI biomarkers (CD47+, CD56+, CD68+, and ADAM17+ EVs) that differ in tSCI, with CD47+ EVs showing a strong correlation with the neurological function in tSCI. Thus, future studies might further specify the relevance of potential tSCI-specific biomarkers and investigate underlying mechanisms of tSCI.

Evaluation of severe rhabdomyolysis on day 30 mortality in trauma patients admitted to intensive care: a propensity score analysis of the Traumabase registry

BACKGROUND

Traumatic rhabdomyolysis (RM) is common and associated with the development of acute kidney injury and potentially with other organ dysfunctions. Thus, RM may increase the risk of death. The primary objective was to assess the effect of severe RM (Creatine Kinase [CK] > 5000 U/L) on 30-day mortality in trauma patients using a causal inference approach.

METHODS

In this multicenter cohort study conducted in France using a national major trauma registry (Traumabase) between January 1, 2012, and July 1, 2023, all patients admitted to a participating major trauma center hospitalized in intensive care unit (ICU) and with CK measurement were included. Confounding variables for both 30-day mortality and exposure were used to establish a propensity score. A doubly robust approach with inverse treatment weighting enabled the calculation of the average treatment effect on the treated (ATT). Analyses were performed in the overall cohort as well as in two subgroups: hemorrhagic shock subgroup (HS) and traumatic brain injury subgroup (TBI). Sensitivity analyses were conducted.

RESULTS

Among the 8592 patients included, 1544 (18.0%) had severe RM. They were predominantly males (78.6%) with median [IQR] age of 41 [27-58] years and severely injured (ISS 20 [13 - 29]) mainly from blunt trauma (90.8%). In the entire cohort, the ATT, expressed as a risk difference, was 0.073 [-0.054 to 0.200]. Considering the 1311 patients in the HS subgroup, the ATT was 0.039 [0.014 to 0.063]. As in the overall cohort, there was no effect on mortality in the TBI subgroup. Severe RM was associated with greater severity of trauma and more complications (whether related to renal function or not) during the ICU stay. Mortality due to multiorgan failure (39.9% vs 12.4%) or septic shock (2.6% vs 0.8%) was more frequent among patients with severe RM.

CONCLUSIONS

Severe RM was not associated with 30-day mortality considering the overall cohort. However, it was associated with a 4.0% increase in 30-day mortality among patients with concurrent hemorrhagic shock. Severe RM plays a significant role in ICU morbidity.

Severe trauma leads to sustained muscle loss, induced frailty, and distinct temporal changes in myokine and chemokine profiles of older patients

INTRODUCTION

Sarcopenia is a known risk factor for adverse outcomes across multiple disease states, including severe trauma. Factors such as age, hyperinflammation, prolonged immobilization, and critical illness may not only exacerbate progression of this disease but may also contribute to the development of induced sarcopenia, or sarcopenia secondary to hospitalization. This study seeks to (1) determine the effects of severe traumatic injury on changes in skeletal muscle mass in older adults; (2) test whether changes in skeletal muscle mass are associated with clinical frailty, physical performance, and health-related quality of life; and (3) examine trauma-induced frailty and temporal changes in myokine and chemokine profiles.

METHODS

A prospective, longitudinal cohort study of 47 critically ill, older (≥45 years) adults presenting after severe blunt trauma was conducted. Repeated measures of computed tomography-based skeletal muscle index, frailty, and quality of life were obtained in addition to selected plasma biomarkers over 6 months.

RESULTS

Severe trauma was associated with significant losses in skeletal muscle mass and increased incidence of sarcopenia from 36% at baseline to 60% at 6 months. Severe trauma also was associated with a transient worsening of induced frailty and reduced quality of life irrespective of sarcopenia status, which returned to baseline by 6 months after injury. Admission biomarker levels were not associated with skeletal muscle index at the time points studied but demonstrated distinct temporal changes across our entire cohort.

CONCLUSIONS

Severe blunt trauma in older adults is associated with increased incidence of induced sarcopenia and reversible induced frailty. Despite muscle wasting, functional decline is transient, with a return to baseline by 6 months, suggesting a need for holistic definitions of sarcopenia and further investigation into long-term functional outcomes in this population.

Utility of hypoxic modalities for musculoskeletal injury rehabilitation in athletes: A narrative review of mechanisms and contemporary perspectives

Recent evidence suggests that different hypoxic modalities might accelerate the rehabilitation process in injured athletes. In this review, the application of hypoxia during rehabilitation from musculoskeletal injury is explored in relation to two principles: (1) facilitating the healing of damaged tissue, and (2) mitigating detraining and inducing training adaptations with a reduced training load. Key literature that explores the underlying mechanisms for these themes is presented, and considerations for practice and future research directions are outlined. For principle (1), passive intermittent hypoxic exposures might accelerate tissue healing through angiogenic and osteogenic mechanisms. Experimental evidence is largely derived from rodent research, so further work is warranted to establish whether clinically meaningful effects can be observed in humans, before optimal protocols are determined (duration, frequency, and hypoxic severity). Regarding principle (2), a hypoxia-related increase in the cardiometabolic stimulus imposed by low-load exercise is appealing for load-compromised athletes. As rehabilitation progresses, a variety of hypoxic modalities can be implemented to enhance adaptation to energy-systems and resistance-based training, and more efficiently return the athlete to competition readiness. While hypoxic modalities seem promising for accelerating musculoskeletal injury rehabilitation in humans, and are already being widely used in practice, a significant gap remains regarding their evidence-based application.

Segmentary exclusion syndrome in hand traumatology - definition, rehabilitation and orthosis

BACKGROUND

Segmentary exclusion syndrome is a motor behavioral disorder consisting in non-use or underuse of a limb or limb segment following local inflammation, most often of traumatic origin, primarily affecting the fingers and hand. It can be associated with somatosensory disorder, limitation of range of motion, and pain.

PURPOSE OF THE STUDY

The objective of this article is to further describe segmentary exclusion syndrome, and to present practical rehabilitation techniques and strategies focused on prevention, assessment and treatment.

Brain-derived extracellular vesicles mediate systemic coagulopathy and inflammation after traumatic brain injury

Traumatic brain injury (TBI) can induce systemic coagulopathy and inflammation, thereby increasing the risk of mortality and disability. However, the mechanism causing systemic coagulopathy and inflammation following TBI remains unclear. In prior research, we discovered that brain-derived extracellular vesicles (BDEVs), originating from the injured brain, can activate the coagulation cascade and inflammatory cells. In this study, we primarily investigated how BDEVs affect systemic coagulopathy and inflammation in peripheral circulation. The results of cytokines and coagulation function indicated that BDEVs can lead to systemic coagulopathy and inflammation by influencing inflammatory factors and chemokines within 24 h. Furthermore, according to flow cytometry and blood cell counter results, we found that BDEVs induced changes in the blood count such as a reduced number of platelets and leukocytes and an increased percentage of neutrophils, macrophages, activated platelets, circulating platelet-EVs, and leukocyte-derived EVs. We also discovered that eliminating circulating BDEVs with lactadherin helped improve coagulopathy and inflammation, relieved blood cell dysfunction, and decreased the circulating platelet-EVs and leukocyte-derived EVs. Our research provides a novel viewpoint and potential mechanism of TBI-associated secondary damage.