Determining the Association Between the Origin of Sepsis and the Severity of Sepsis in Intensive Care Unit (ICU) Patients Using Acute Physiology and Chronic Health Evaluation (APACHE) IV

Objective The objective of this study is to compare the outcomes of hospital mortality, the requirement of invasive ventilation, vasopressor requirement, duration of vasopressor requirement, and duration of intensive care unit (ICU) stay among the different causes of sepsis and to determine which cause of sepsis had the most severe outcomes. Methods A retrospective chart review was done in critically ill adult patients who were admitted with sepsis to the ICU from July 2017 until July 2019. Acute Physiology and Chronic Health Evaluation (APACHE) IV scores were calculated on patients admitted to ICU on day one of ICU admission. Each patient was then evaluated for outcomes of hospital mortality, need for invasive ventilation, requirement of vasopressors, duration of vasopressors, and duration of ICU stay. The outcomes were then compared between the different sources of sepsis to determine which source of sepsis had the highest severity. Results In total, 176 patients were included in the study. Ninety-three patients were admitted with respiratory sepsis, 26 patients were admitted with gastrointestinal sepsis, 31 patients were admitted with urosepsis, and 26 patients were admitted with other miscellaneous causes of sepsis. The hospital mortality was highest in the respiratory sepsis group at 32%, with a trend towards statistical significance with a P value of 0.057. ICU stay duration was highest in patients with respiratory sepsis at six days, with a statistically significant P value of < 0.001. The need for invasive ventilation was highest in patients with respiratory sepsis at 64%, with a statistically significant P value of < 0.001. The requirement of vasopressor support was highest in patients with respiratory sepsis at 47% and the duration of vasopressors was highest in both respiratory and gastrointestinal sepsis at three days, however, there was no statistical significance. Conclusion Among the different origins of sepsis, the patients with respiratory sepsis had the most severe outcomes, with the highest need for invasive ventilation and the highest ICU stay duration.

Renal transplant and hemostasis: early postoperative changes in recipients and donors

Background

The benefit of administering pharmacologic thromboprophylaxis following renal transplantation remains uncertain.

Objectives

To compare hemostatic parameters before and after renal transplant surgery in both recipients and their donors at predetermined time points.

Methods

Blood samples were collected at baseline (T1), immediately after surgery (T2), and at 24 hours after surgery (T3) in both recipients and donors and at 72 (T4) and 120 hours (T5) from recipients only. Assays included in vitro thrombin generation, factor VIII (FVIIIc) activity, von Willebrand factor (VWF) antigen, D-dimer, antithrombin activity, prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complexes, and plasminogen activator inhibitor-1 (PAI-1) antigen.

Results

Fifty-two patients (28 recipients and 24 donors) were enrolled. Both donors and recipients had increased FVIIIc, VWF, F1 + 2, D-dimer, and PAI immediately after surgery but reduced antithrombin. Mixed-model analysis showed that the magnitude of change over time (between T1 and T3) for FVIIIc (mean estimated difference [MED], 72; 95% CI, 41-102; P < .0001), VWF (MED, 89; 95% CI, 35-142; P = .001), F1 + 2 (MED, 283; 95% CI, 144-422; P < .0001), thrombin-antithrombin complexes (MED, 3.5; 95% CI, 1.9-5.1; P < .0001), D-dimer (MED, 2.2; 95% CI, 1.0-3.3; P < .0001), PAI-1 (MED, 9.2; 95% CI, 3.4-14.9; P = .002), and time to peak thrombin generation (MED, 1.5; 95% CI, 0.35-2.7; P = .01) was more significant in recipients than in donors.

Conclusion

Persistence of a hypercoagulable state was more prominent in recipients after 24 hours despite recovery in renal function and initiation of thromboprophylaxis.

The characteristics and impact of source of infection on sepsis-related ICU outcomes

BACKGROUND

Source of infection is an independent predictor of sepsis-related mortality. To date, studies have failed to evaluate differences in septic patients based on the source of infection.

METHODS

Retrospective study of all patients with sepsis admitted to the ICU of a university hospital within a 12month time period.

RESULTS

Sepsis due to intravascular device and multiple sources had the highest number of positive blood cultures and microbiology whereas lung and abdominal sepsis had the least. The observed hospital mortality was highest for sepsis due to multiple sources and unknown cause, and was lowest when due to abdominal, genitourinary (GU) or skin/soft tissue. Patients with sepsis due to lungs, unknown and multiple sources had the highest rates of multi-organ failure, whereas those with sepsis due to GU and skin/soft tissue had the lowest rates. Those with multisource sepsis had a significantly higher median ICU length of stay and hospital cost.

CONCLUSION

There are significant differences in patient characteristics, microbiology positivity, organs affected, mortality, length of stay and cost based on the source of sepsis. These differences should be considered in future studies to be able to deliver personalized care.

A new method for removing endotoxin from plasma using hemocompatible affinity chromatography technology, applicable for extracorporeal treatment of septic patients

The pathogenesis of sepsis begins with the proliferation of micro-organisms at a site of infection, followed by invasion of the bloodstream and other organs. Gram-negative bacteria account for a large part of sepsis cases. The structural component of Gram-negative bacteria, endotoxin or lipopolysaccharide (LPS), induces the synthesis and release of endogenous mediators of sepsis. A growing number of investigations of the molecular mechanisms occurring in sepsis, point to endotoxin as a central mediator leading to multi-organ failure and death. In numerous clinical trials, attempts to target molecules downstream of endotoxin have been made, but have not been associated with improved survival. We describe an affinity-based system for the selective removal of endotoxin from plasma. The small-scale device, a 1.5 ml cartridge, contains beads that bind endotoxin with high specificity and efficiency. In addition, evidence is presented that this device does not affect plasma hemostasis, nor does it activate the complement system. Taken together, these results represent a proof of principle for endotoxin removal from plasma, which may be of clinical value to treat sepsis by extracorporeal circulation of the blood through a scaled-up version of this endotoxin-removing device.

Coagulation factor II from rock bream (Oplegnathus fasciatus): First report on the molecular biological function and expression analysis in the teleost

The rapid haemostasis of fish prevents bleeding or infection that could be caused by physical properties of the aquatic environment. Additionally, the innate immune system is the first line of defence against infection and is responsible for the recognition of pathogen-associated molecular patterns, which are important for the activation of acquired immune responses. Coagulation factor II (CFII) is an important factor in the coagulation system and is involved in recognition and interaction with various bacterial and extracellular proteins. In this study, we identified and characterised the gene encoding CFII in rock bream (Oplegnathus fasciatus) (RbCFII) and analysed its expression in various tissues after a pathogen challenge. The full-length RbCFII cDNA (2079 bp) contained an open reading frame of 1854 bp encoding 617 amino acids. Alignment analysis revealed that a gamma-carboxyglutamic acid-rich domain, two kringle domains, and a trypsin-like serine protease domain of the deduced protein were well conserved. RbCFII was ubiquitously expressed in all tissues examined but, predominantly detected in the liver and skin. RbCFII expression was dramatically up-regulated in the kidney, spleen and liver after infection with Edwardsiella tarda, Streptococcus iniae, or red seabream iridovirus. The recombinant protein RbCFII (rRbCFII) produced using an Escherichia coli expression system was able to bind all examined bacteria. Interestingly, rRbCFII has agglutination activities towards E. coli and E. tarda, while no agglutination was shown toward Vibrio ordalii and S. iniae. These findings indicate that rRbCFII performs an immunological function in the immune response, and might be involved in innate immunity as well as blood coagulation.

An alternate pathophysiologic paradigm of sepsis and septic shock: implications for optimizing antimicrobial therapy

The advent of modern antimicrobial therapy following the discovery of penicillin during the 1940s yielded remarkable improvements in case fatality rate of serious infections including septic shock. Since then, pathogens have continuously evolved under selective antimicrobial pressure resulting in a lack of significant improvement in clinical effectiveness in the antimicrobial therapy of septic shock despite ever more broad-spectrum and potent drugs. In addition, although substantial effort and money has been expended on the development novel non-antimicrobial therapies of sepsis in the past 30 years, clinical progress in this regard has been limited. This review explores the possibility that the current pathophysiologic paradigm of septic shock fails to appropriately consider the primacy of the microbial burden of infection as the primary driver of septic organ dysfunction. An alternate paradigm is offered that suggests that has substantial implications for optimizing antimicrobial therapy in septic shock. This model of disease progression suggests the key to significant improvement in the outcome of septic shock may lie, in great part, with improvements in delivery of existing antimicrobials and other anti-infectious strategies. Recognition of the role of delays in administration of antimicrobial therapy in the poor outcomes of septic shock is central to this effort. However, therapeutic strategies that improve the degree of antimicrobial cidality likely also have a crucial role.

Role of reactive oxygen and nitrogen species in the vascular responses to inflammation

Inflammation is a complex and potentially life-threatening condition that involves the participation of a variety of chemical mediators, signaling pathways, and cell types. The microcirculation, which is critical for the initiation and perpetuation of an inflammatory response, exhibits several characteristic functional and structural changes in response to inflammation. These include vasomotor dysfunction (impaired vessel dilation and constriction), the adhesion and transendothelial migration of leukocytes, endothelial barrier dysfunction (increased vascular permeability), blood vessel proliferation (angiogenesis), and enhanced thrombus formation. These diverse responses of the microvasculature largely reflect the endothelial cell dysfunction that accompanies inflammation and the central role of these cells in modulating processes as varied as blood flow regulation, angiogenesis, and thrombogenesis. The importance of endothelial cells in inflammation-induced vascular dysfunction is also predicated on the ability of these cells to produce and respond to reactive oxygen and nitrogen species. Inflammation seems to upset the balance between nitric oxide and superoxide within (and surrounding) endothelial cells, which is necessary for normal vessel function. This review is focused on defining the molecular targets in the vessel wall that interact with reactive oxygen species and nitric oxide to produce the characteristic functional and structural changes that occur in response to inflammation. This analysis of the literature is consistent with the view that reactive oxygen and nitrogen species contribute significantly to the diverse vascular responses in inflammation and supports efforts that are directed at targeting these highly reactive species to maintain normal vascular health in pathological conditions that are associated with acute or chronic inflammation.

Early antimicrobial therapy in severe sepsis and septic shock

The advent of modern antimicrobial therapy following the discovery of penicillin during the 1940s yielded remarkable improvements in the case fatality rates of serious infections, including septic shock. Since then, pathogens have continuously evolved under selective antimicrobial pressure, resulting in a lack of additional significant improvement in clinical effectiveness of antimicrobial therapy of septic shock despite ever more broad-spectrum and potent drugs. In addition, although substantial effort and money were expended on the development of novel nonantimicrobial therapies of sepsis in the past 30 years, clinical progress in this regard has been limited. This article explores the possibility that the key to significant improvement in the outcome of septic shock may lie, in great part, with improvements in delivery of existing antimicrobials. Recognizing the role of delays in administration of antimicrobial therapy in the poor outcomes of septic shock is central to this effort.

Inflammatory pathways in female reproductive health and disease

Inflammation involves alterations to vascular and immune cell function. It is well recognised that many physiological reproductive events such as ovulation, menstruation, implantation and onset of labour display hallmark signs of inflammation. These are orchestrated by specific molecular pathways involving a host of growth factors, cytokines, chemokines and lipid mediators. Resumption of normal reproductive function involves prompt and proper resolution of these inflammatory pathways. Recent literature confirms that resolution of inflammatory pathways involves specific biochemical events that are activated to re-establish homeostasis in the affected tissue. Moreover, initiation and maintenance of inflammatory pathways are the key components of many pathologies of the reproductive tract and elsewhere in the body. The onset of reproductive disorders or disease may be the result of exacerbated activation and maintenance of inflammatory pathways or their dysregulated resolution. This review will address the role of inflammatory events in normal reproductive function and its pathologies.

In vitro evaluation of blood coagulation activation and microthrombus formation by a microchannel array flow analyzer

An in vitro assay system for evaluating microthrombus formation in whole blood has not yet been established. In this study, we characterized the relationship between coagulation activation and capillary occlusion in an in vitro assay system using a microchannel array flow analyzer (MC-FAN), which can evaluate microthrombus formation in whole blood as a function of blood flow rate. The flow rate of lipopolysaccharide (LPS)-treated whole blood decreased in a dose- and time-dependent manner. Addition of LPS-pretreated mononuclear cells (PBMCs) to whole blood also decreased the flow rate. Treatment with an anti-tissue factor (TF) antibody blocked the LPS-induced decrease in blood flow rate, suggesting that TF expressed on PBMCs is responsible for decreased blood flow in the microchannels. Known anticoagulants and anti-platelet agents also inhibited the LPS-induced decrease in blood flow rate. Thrombin-antithrombin complexes were increased in LPS-stimulated whole blood, and decreased by anticoagulants but not by anti-platelet agents. These findings suggest that occlusion in microchannels occurs mainly by formation of microthrombi composed of fibrin nets and platelet aggregates, which result from TF expression on activated PBMCs. In addition, the MC-FAN was found to be useful for in vitro evaluation of antithrombotic agents in the capillary.

[Pathophysiological role of endotoxins, a common denominator to various diseases]

A growing number of investigations point to endotoxin or lipopolysaccharide as a central player in many pathophysiological states and diseases. Endotoxins are one of the most toxic biological contaminants continuously shed by both dead and live Gram negative bacteria. Endotoxins induce the primitive form of defense called innate immunity. Endotoxins have been related to inflammatory reactions observed in patients suffering from respiratory distress syndrome, multiorgan failure and septic shock, hepatic diseases, or in subjects affected by graft versus host disease after allogeneic transplantation. As our understanding of the molecular mechanisms underlying pathologies progresses, more diseases involving endotoxins emerge. Although these illnesses are multifactorial, the objective of this article is to review some of the common and distinct processes involving endotoxins in various disease states.

Thrombin induces nitric-oxide synthase via Galpha12/13-coupled protein kinase C-dependent I-kappaBalpha phosphorylation and JNK-mediated I-kappaBalpha degradation

An imbalance between thrombin and antithrombin III contributed to vascular hyporeactivity in sepsis, which can be attributed to excess NO production by inducible nitric-oxide synthase (iNOS). In view of the importance of the thrombin-activated coagulation pathway and excess NO as the culminating factors in vascular hyporeactivity, this study investigated the effects of thrombin on the induction of iNOS and NO production in macrophages. Thrombin induced iNOS protein in the Raw264.7 cells, which was inhibited by a thrombin inhibitor, LB30057. Thrombin increased NF-kappaB DNA binding, whose band was supershifted with anti-p65 and anti-p50 antibodies. Thrombin elicited the phosphorylation and degradation of I-kappaBalpha prior to the nuclear translocation of p65. The NF-kappaB-mediated iNOS induction was stimulated by the overexpression of activated mutants of Galpha(12/13) (Galpha(12/13)QL). Protein kinase C depletion inhibited I-kappaBalpha degradation, NF-kappaB activation, and iNOS induction by thrombin or the iNOS induction by Galpha(12/13)QL. JNK, p38 kinase, and ERK were all activated by thrombin. JNK inhibition by the stable transfection with a dominant negative mutant of JNK1 (JNK1(-)) completely suppressed the NF-kappaB-mediated iNOS induction by thrombin. Conversely, the inhibition of p38 kinase enhanced the expression of iNOS. In addition, JNK and p38 kinase oppositely controlled the NF-kappaB-mediated iNOS induction by Galpha(12/13)QL. Hence, iNOS induction by thrombin was regulated by the opposed functions of JNK and p38 kinase downstream of Galpha(12/13). In the JNK1(-) cells, thrombin did not increase either the NF-kappaB binding activity or I-kappaBalpha degradation despite I-kappaBalpha phosphorylation. These results demonstrated that thrombin induces iNOS in macrophages via Galpha(12) and Galpha(13), which leads to NF-kappaB activation involving the protein kinase C-dependent phosphorylation of I-kappaBalpha and the JNK-dependent degradation of phosphorylated I-kappaBalpha.

Points of control in inflammation

Inflammation is a complex set of interactions among soluble factors and cells that can arise in any tissue in response to traumatic, infectious, post-ischaemic, toxic or autoimmune injury. The process normally leads to recovery from infection and to healing, However, if targeted destruction and assisted repair are not properly phased, inflammation can lead to persistent tissue damage by leukocytes, lymphocytes or collagen. Inflammation may be considered in terms of its checkpoints, where binary or higher-order signals drive each commitment to escalate, go signals trigger stop signals, and molecules responsible for mediating the inflammatory response also suppress it, depending on timing and context. The non-inflammatory state does not arise passively from an absence of inflammatory stimuli; rather, maintenance of health requires the positive actions of specific gene products to suppress reactions to potentially inflammatory stimuli that do not warrant a full response.