Sepsis 3 and the burns patient: do we need Sepsis 3.1?

Application of Phagotherapy in the Treatment of Burn Patients (Review)

Treatment of patients with a burn injury is a complex process involving multicomponent multidirectional intensive therapy of the majority of organs and systems damaged by thermal effects on the skin, alternating with repeated surgical interventions aimed at removing nonviable tissues with subsequent plastic closure of wound defects. After the recovery from the burn shock, local infectious complications are considered to be the leading problem that decelerates the process of recovery and is the main cause of lethal outcomes. Since the skin integrity is broken, microorganisms penetrate readily into the internal environment of the human organism resulting in a septic state with multiple organ failure. A widespread and often uncontrollable use of antibacterial drugs in medical practice has led to the emergence of multiple drug resistance (MDR) in microorganisms. Introduction of drugs made on the basis of bacteriophages into practice is presently becoming increasingly important. This is confirmed by the growing interest in this field of pharmacology, the development of special programs aimed at studying the processes of phage and bacterial cell interaction. This review presents the main types of bacteria pertaining to MDR pathogens, principles of their classification, and the risk factors for infecting patients. The mechanisms of the selective action of phage particles on a bacterial cell and the possibility of using phage therapy in the treatment of burn injury (experimental and clinical data) based on the analysis of foreign literature are demonstrated as well as new positive properties of phages related to the changes in the macroorganism immune status caused by the interaction with bacteriophage particles.

Incidence and Time Point of Sepsis Detection as Related to Different Sepsis Definitions in Severely Burned Patients and Their Accompanying Time Course of Pro-Inflammatory Biomarkers

Background: Diagnosis of sepsis in burn patients remains difficult for various reasons. One major problem is the definition of sepsis itself. Therefore, previous and current sepsis definitions are a matter of ongoing validation, but a well-defined consensus on which clinical and laboratory parameters to incorporate in such a definition is lacking. The aim of the present study was to compare the incidence and time-related occurrence of septic events according to different definitions as well as their accompanying time course of pro-inflammatory biomarkers. Methods: Across the first 14 days after admission, the incidence and time point of sepsis according to three different definitions (Sepsis-3, Sepsis American Burns Association [ABA] 2007, Sepsis Zurich Burn Center) were assessed on a daily basis in adult burn patients with total body surface area (TBSA) ≥15% admitted to the Zurich Burn Center between May 2015 and October 2018. In order to investigate how well daily drawn proinflammatory biomarkers (white blood cells (WBCs), C-reactive protein (CRP), procalcitonin (PCT), and novel pancreatic stone protein (PSP)) reflect the progression of sepsis depending on its type of definition, a longitudinal mixed model analysis was performed across the first 14 days for septic and non-septic patients. Additionally, the relative increase of biomarker levels 24, 48, and 72 h prior to a septic event was analyzed for each definition used. Results: In our cohort of 90 severely burned patients, Sepsis-3 identified 46 patients (51.1%) as septic, while ABA 2007 and the Zurich Burn Center definition counted 33 patients (36.7%) and 24 patients (26.6%), respectively. Sepsis-3 detected sepsis about 1 day earlier than Sepsis ABA 2007 (p < 0.001) and about 0.5 days earlier than Sepsis Zurich Burn Center (p = 0.04). The course of pro-inflammatory biomarkers was largely unaffected by the type of sepsis definition. Irrespective of the sepsis definition, PSP was the only marker to demonstrate a highly significant interaction between time and group (sepsis versus no sepsis) (p < 0.001) with a 3.3–5.5-fold increase within 72 h before the event of sepsis, whereas CRP, PCT, and WBC showed only mild undulations. Conclusions: Despite the ongoing dilemma of how to define sepsis in burn patients, a continually calculated SOFA score as used in Sepsis-3 is advantageous to early identify a patient’s detrimental progression to sepsis. Inclusion of biomarkers, such as PSP, may help support the burn specialist’s diagnosis of sepsis and could improve the diagnostic performance of current and future definitions in burn patients.

Detection of Infection and Sepsis in Burns

Background: Infection is the most frequent complication after severe burns and has a propensity to progress into sepsis then septic shock and multiple organ dysfunction syndrome (MODS). Improving outcomes in acute burn care depends on early detection of infection to allow prompt interventions. Diagnosis of sepsis in severe burns is uniquely challenging because otherwise-typical clinical signs are masked by the hypermetabolic state and systemic inflammation induced by the burn itself. For this reason, burns have historically been excluded from high-impact studies on the diagnosis and treatment of sepsis. Methods: This article provides a comprehensive three-fold review of current findings and guidelines pertinent to the early detection of infection and sepsis in severe burns. Results: First, evidence-based detection of the most common infections encountered in the burn intensive care unit is reviewed. Second, we analyze the evolution of the diagnostic criteria for sepsis and the evidence regarding their utility in severe burns. Last, we examine the development of biomarkers, from procalcitonin to molecular genomics, for the detection of sepsis. Conclusions: Although gold standard methods of early detection of sepsis in burn patients have yet to be identified, improved understanding and appropriate application of the available diagnostic criteria and assays are paramount to providing effective care of patients with severe burns.

Immature platelet indices alongside procalcitonin for sensitive and specific identification of bacteremia in the intensive care unit

Hematological markers that can be rapidly analyzed and regularly monitored during a patient's stay on ICU, and that can identify bacterial causes of sepsis are being extensively sought. The significance of platelets in early immunological responses provides justification for assessing their usefulness in the identification of bacteremia amongst sepsis patients. In this preliminary study, the full blood count, including the platelet count by impedance (PLT-I), Immature Platelet Fraction (IPF%) and absolute immature platelet count (AIPC), were analyzed in eighty-two sepsis patients daily over the first 5 days stay on ICU. C-Reactive Protein (CRP), procalcitonin (PCT), and lactate were also analyzed daily. Blood cultures confirmed or excluded the presence of bacteremia. PCT provided the earliest indicator of bacteremia, with significant differences between the two cohorts on day 1. The change in IPF% and AIPC from day 1 to day 2 (Δ IPF% and Δ AIPC) provided the most accurate indication; A combination of Δ IPF% and day 2 PCT, provided a positive predictive value and negative predictive value of 100% and 96.10%, respectively. These data provide strong justification for larger multi-center validation studies to confirm the usefulness of these platelet indices during the assessment of sepsis on the ICU.

Prognostic accuracy of SOFA, qSOFA and SIRS criteria in hematological cancer patients: a retrospective multicenter study

Background

With Sepsis-3, the increase in sequential organ failure assessment (SOFA) as a clinical score for the identification of patients with sepsis and quickSOFA (qSOFA) for the identification of patients at risk of sepsis outside the intensive care unit (ICU) were introduced in 2016. However, their validity has been questioned, and their applicability in different settings and subgroups, such as hematological cancer patients, remains unclear. We therefore assessed the validity of SOFA, qSOFA, and the systemic inflammatory response syndrome (SIRS) criteria regarding the diagnosis of sepsis and the prediction of in-hospital mortality in a multicenter cohort of hematological cancer patients treated on ICU and non-ICU settings.

Methods

We retrospectively calculated SIRS, SOFA, and qSOFA scores in our cohort and applied the definition of sepsis as "life-threatening organ dysfunction caused by dysregulated host response to infection" as reference. Discriminatory capacity was assessed using the area under the receiver operating characteristic curve (AUROC).

Results

Among 450 patients with hematological cancer (median age 58 years, 274 males [61%]), 180 (40%) had sepsis of which 101 (56%) were treated on ICU. For the diagnosis of sepsis, sensitivity was 86%, 64%, and 42% for SIRS, SOFA, and qSOFA, respectively. However, the AUROCs of SOFA and qSOFA indicated better discrimination for sepsis than SIRS (SOFA, 0.69 [95% CI, 0.64-0.73] p < 0.001; qSOFA, 0.67 [95% CI, 0.62-0.71] p < 0.001; SIRS, 0.57 [95% CI, 0.53-0.61] p < 0.001).In-hospital mortality was 40% and 14% in patients with and without sepsis, respectively (p < 0.001). Regarding patients with sepsis, mortality was similar in patients with positive and negative SIRS scores (39% vs. 40% (p = 0.899), respectively). For patients with qSOFA ≥ 2, mortality was 49% compared to 33% for those with qSOFA < 2 (p = 0.056), and for SOFA 56% vs. 11% (p < 0.001), respectively. SOFA allowed significantly better discrimination for in-hospital mortality (AUROC 0.74 [95% CI, 0.69-0.79] p < 0.001) than qSOFA (AUROC 0.65 [95% CI, 0.60-0.71] p < 0.001) or SIRS (AUROC 0.49 [95% CI, 0.44-0.54] p < 0.001).

Conclusions

An increase in SOFA score of ≥ 2 had better prognostic accuracy for both diagnosis of sepsis and in-hospital mortality in this setting, and especially on ICU, we observed limited validity of SIRS criteria and qSOFA in identifying hematological patients with sepsis and at high risk of death.

Methodological challenges in European ethics approvals for a genetic epidemiology study in critically ill patients: the GenOSept experience

BACKGROUND

During the set-up phase of an international study of genetic influences on outcomes from sepsis, we aimed to characterise potential differences in ethics approval processes and outcomes in participating European countries.

METHODS

Between 2005 and 2007 of the FP6-funded international Genetics Of Sepsis and Septic Shock (GenOSept) project, we asked national coordinators to complete a structured survey of research ethic committee (REC) approval structures and processes in their countries, and linked these data to outcomes. Survey findings were reconfirmed or modified in 2017.

RESULTS

Eighteen countries participated in the study, recruiting 2257 patients from 160 ICUs. National practices differed widely in terms of composition of RECs, procedures and duration of the ethics approval process. Eight (44.4%) countries used a single centralised process for approval, seven (38.9%) required approval by an ethics committee in each participating hospital, and three (16.7%) required both. Outcomes of the application process differed widely between countries because of differences in national legislation, and differed within countries because of interpretation of the ethics of conducting research in patients lacking capacity. The RECs in four countries had no lay representation. The median time from submission to final decision was 1.5 (interquartile range 1-7) months; in nine (50%) approval was received within 1 month; six took over 6 months, and in one 24 months; had all countries been able to match the most efficient approvals processes, an additional 74 months of country or institution-level recruitment would have been available. In three countries, rejection of the application by some local RECs resulted in loss of centres; and one country rejected the application outright.

CONCLUSIONS

The potential benefits of the single application portal offered by the European Clinical Trials Regulation will not be realised without harmonisation of research ethics committee practices as well as national legislation.