[Therapy of sepsis]. / Therapie der Sepsis.

Sepsis as a development of an acute infection-related organ dysfunction significantly increases the risk of death for the patient. Therefore, fast and consistent management is required. The sepsis bundle is a convenient algorithm for initial sepsis therapy within the first hour of sepsis diagnosis consisting of blood cultures, lactate measurement, antibiotics, fluid resuscitation, and vasopressor therapy. Cristalloid solutions are first choice for fluid therapy but albumin and gelatine may be considered if colloid solutions are required. Norepinephrine is the vasopressor of first choice. After initial therapy, further fluid resuscitation should be guided by dynamic criteria. Vasopressin may be added as an additional vasopressor. Goal of resuscitation is to achieve lactate clearance. In shock refractory to therapy, addition of hydrocortisone (200 mg/day) should be considered. Further additional therapies such as immunoglobulins, blood purification, and metabolic resuscitation (combination of hydrocortisone, thiamine, vitamine C) are currently not supported by studies and should not be considered as standard therapy.

Adverse effects of delayed antimicrobial treatment and surgical source control in adults with sepsis: results of a planned secondary analysis of a cluster-randomized controlled trial.

BACKGROUND: Timely antimicrobial treatment and source control are strongly recommended by sepsis guidelines, however, their impact on clinical outcomes is uncertain. METHODS: We performed a planned secondary analysis of a cluster-randomized trial conducted from July 2011 to May 2015 including forty German hospitals. All adult patients with sepsis treated in the participating ICUs were included. Primary exposures were timing of antimicrobial therapy and delay of surgical source control during the first 48 h after sepsis onset. Primary endpoint was 28-day mortality. Mixed models were used to investigate the effects of timing while adjusting for confounders. The linearity of the effect was investigated by fractional polynomials and by categorizing of timing. RESULTS: Analyses were based on 4792 patients receiving antimicrobial treatment and 1595 patients undergoing surgical source control. Fractional polynomial analysis identified a linear effect of timing of antimicrobials on 28-day mortality, which increased by 0.42% per hour delay (OR with 95% CI 1.019 [1.01, 1.028], p ≤ 0.001). This effect was significant in patients with and without shock (OR = 1.018 [1.008, 1.029] and 1.026 [1.01, 1.043], respectively). Using a categorized timing variable, there were no significant differences comparing treatment within 1 h versus 1-3 h, or 1 h versus 3-6 h. Delays of more than 6 h significantly increased mortality (OR = 1.41 [1.17, 1.69]). Delay in antimicrobials also increased risk of progression from severe sepsis to septic shock (OR per hour: 1.051 [1.022, 1.081], p ≤ 0.001). Time to surgical source control was significantly associated with decreased odds of successful source control (OR = 0.982 [0.971, 0.994], p = 0.003) and increased odds of death (OR = 1.011 [1.001, 1.021]; p = 0.03) in unadjusted analysis, but not when adjusted for confounders (OR = 0.991 [0.978, 1.005] and OR = 1.008 [0.997, 1.02], respectively). Only, among patients with septic shock delay of source control was significantly related to risk-of death (adjusted OR = 1.013 [1.001, 1.026], p = 0.04). CONCLUSIONS: Our findings suggest that management of sepsis is time critical both for antimicrobial therapy and source control. Also patients, who are not yet in septic shock, profit from early anti-infective treatment since it can prevent further deterioration. Trial registration ClinicalTrials.gov ( NCT01187134 ). Registered 23 August 2010, NCT01187134.

Population pharmacokinetics and probability of target attainment in patients with sepsis under renal replacement therapy receiving continuous infusion of meropenem: Sustained low-efficiency dialysis and continuous veno-venous haemodialysis.

AIMS: To describe the population pharmacokinetics (PK) and probability of target attainment (PTA) of continuous infusion (CI) of meropenem in septic patients receiving renal replacement therapy (RRT). METHODS: Fifteen patients without RRT, 13 patients receiving sustained low-efficiency dialysis and 12 patients receiving continuous veno-venous haemodialysis were included. Population PK analysis with Monte Carlo simulations for different dosing regimens was performed. For minimum inhibitory concentration 2 mg/L was chosen. The target was set as 50% time ≥4× minimum inhibitory concentration. RESULTS: The PK of meropenem was best described by a 1-compartment model with linear elimination. Serum creatinine, residual diuresis and time on RRT, with no difference between sustained low-efficiency dialysis and continuous veno-venous haemodialysis, were found to be significant covariates affecting clearance, explaining >20% of the clearance between subject variability. PTA analysis showed that in patients with RRT, 2 g/24 h, meropenem CI achieved a PTA of 95%. In patients without RRT, the target was achieved with 3 g/24 h CI or prolonged infusion of 1 g meropenem over 8 hours but not with bolus application of 1 g meropenem for 8 hours. Only 2 patients (both without RRT) had meropenem concentrations below the target level. However, approximately half of the patients with RRT receiving CI 3 g/24 h meropenem had toxic concentrations. CONCLUSION: We found relevant PK variability for meropenem CI in septic patients with or without RRT, leading to a substantial risk for overdosing in patients with RRT. This finding highlights the strong demand for personalized dosing in critically ill patients.

Fever and hypothermia represent two populations of sepsis patients and are associated with outside temperature.

BACKGROUND: Fever and hypothermia have been observed in septic patients. Their influence on prognosis is subject to ongoing debates. METHODS: We did a secondary analysis of a large clinical dataset from a quality improvement trial. A binary logistic regression model was calculated to assess the association of the thermal response with outcome and a multinomial regression model to assess factors associated with fever or hypothermia. RESULTS: With 6542 analyzable cases we observed a bimodal temperature response characterized by fever or hypothermia, normothermia was rare. Hypothermia and high fever were both associated with higher lactate values. Hypothermia was associated with higher mortality, but this association was reduced after adjustment for other risk factors. Age, community-acquired sepsis, lower BMI and lower outside temperatures were associated with hypothermia while bacteremia and higher procalcitonin values were associated with high fever. CONCLUSIONS: Septic patients show either a hypothermic or a fever response. Whether hypothermia is a maladaptive response, as indicated by the higher mortality in hypothermic patients, or an adaptive response in patients with limited metabolic reserves under colder environmental conditions, remains an open question. Trial registration The original trial whose dataset was analyzed was registered at ClinicalTrials.gov (NCT01187134) on August 23, 2010, the first patient was included on July 1, 2011.

An international comparison of the cost of fluid resuscitation therapies.

OBJECTIVE: Fluid resuscitation is a ubiquitous intervention in the management of patients treated in the intensive care unit, which has implications for intensive care unit resourcing and budgets. Our objective was to calculate the relative cost of resuscitation fluids in several countries to inform future economic evaluations. METHODS: We collected site-level data regarding the availability and cost of fluids as part of an international survey. We normalised costs to net present values using purchasing power parities and published inflation figures. Costs were also adjusted for equi-effective dosing based on intravascular volume expansion effectiveness and expressed as US dollars (USD) per 100 mL crystalloid equivalent. RESULTS: A total of 187 sites had access to cost data. Between countries, there was an approximate six fold variation in the cost of crystalloids and colloids overall. The average cost for crystalloids overall was less than 1 USD per 100 mL. In contrast, colloid fluids had higher average costs (59 USD per 100 mL). After adjusting for equi-effective dosing, saline was ∼27 times less costly than albumin (saline: 0.6 USD per 100 mL crystalloid equivalent; albumin 4-5%: 16.4 USD; albumin 20-25%: 15.8 USD) and ∼4 times less costly than hydroxyethyl starch solution (saline: 0.6 USD; hydroxyethyl starch solution: 2.5 USD). Buffered salt solutions, such as compound sodium acetate solutions (e.g., Plasmalyte®), had the highest average cost of crystalloid fluids, costing between 3 and 4 USD per 100 mL. CONCLUSION: The cost of fluid varies substantially between fluid types and between countries, although normal (0.9%) saline is consistently less costly than colloid preparations and some buffered salt solutions. These data can be used to inform future economic evaluations of fluid preparations.

Bloodstream infection due to Enterobacter ludwigii, correlating with massive aggregation on the surface of a central venous catheter.

We report a case of catheter associated bloodstream infection due to Enterobacter ludwigii with a massive aggregation on the outside surface of a central venous catheter (CVC). The 57 years old patient with a history of spondylodiscitis and Staphylococcus aureus-associated endocarditis was admitted to the intensive care unit for acute cerebral infarction. The patient developed signs of infections and the CVC was removed 11 days after placement. The infectious agent was identified by standard diagnostics to the genus level as belonging to the Enterobacter cloacae complex, and additional molecular testing determined the species as E. ludwigii. The catheter was selected for a study aiming to identify the influence of blood components on the formation of central venous catheter-associated biofilms. In this course a massive biofilm was recognized and is presented here.

Correction to: The early identification of disease progression in patients with suspected infection presenting to the emergency department: a multi-centre derivation and validation study.

In the publication of this article [1], there are two errors in contributing author affiliations. This has now been included in this correction article.

The early identification of disease progression in patients with suspected infection presenting to the emergency department: a multi-centre derivation and validation study.

BACKGROUND: There is a lack of validated tools to assess potential disease progression and hospitalisation decisions in patients presenting to the emergency department (ED) with a suspected infection. This study aimed to identify suitable blood biomarkers (MR-proADM, PCT, lactate and CRP) or clinical scores (SIRS, SOFA, qSOFA, NEWS and CRB-65) to fulfil this unmet clinical need. METHODS: An observational derivation patient cohort validated by an independent secondary analysis across nine EDs. Logistic and Cox regression, area under the receiver operating characteristic (AUROC) and Kaplan-Meier curves were used to assess performance. Disease progression was identified using a composite endpoint of 28-day mortality, ICU admission and hospitalisation > 10 days. RESULTS: One thousand one hundred seventy-five derivation and 896 validation patients were analysed with respective 28-day mortality rates of 7.1% and 5.0%, and hospitalisation rates of 77.9% and 76.2%. MR-proADM showed greatest accuracy in predicting 28-day mortality and hospitalisation requirement across both cohorts. Patient subgroups with high MR-proADM concentrations (≥ 1.54 nmol/L) and low biomarker (PCT < 0.25 ng/mL, lactate < 2.0 mmol/L or CRP < 67 mg/L) or clinical score (SOFA < 2 points, qSOFA < 2 points, NEWS < 4 points or CRB-65 < 2 points) values were characterised by a significantly longer length of hospitalisation (p < 0.001), rate of ICU admission (p < 0.001), elevated mortality risk (e.g. SOFA, qSOFA and NEWS HR [95%CI], 45.5 [10.0-207.6], 23.4 [11.1-49.3] and 32.6 [9.4-113.6], respectively) and a greater number of disease progression events (p < 0.001), compared to similar subgroups with low MR-proADM concentrations (< 1.54 nmol/L). Increased out-patient treatment across both cohorts could be facilitated using a derivation-derived MR-proADM cut-off of < 0.87 nmol/L (15.0% and 16.6%), with decreased readmission rates and no mortalities. CONCLUSIONS: In patients presenting to the ED with a suspected infection, the blood biomarker MR-proADM could most accurately identify the likelihood of further disease progression. Incorporation into an early sepsis management protocol may therefore aid rapid decision-making in order to either initiate, escalate or intensify early treatment strategies, or identify patients suitable for safe out-patient treatment.

Influence of pathogen and focus of infection on procalcitonin values in sepsis patients with bacteremia or candidemia.

BACKGROUND: This study aimed to evaluate the accuracy of procalcitonin (PCT) serum concentrations to diagnose Gram-negative bacteremia and the association of PCT serum concentrations with more specific pathogens and the focus of infection. METHODS: Secondary analysis of the prospectively collected patient-level dataset from a cluster randomized quality improvement trial was performed. The trial included sepsis patients with organ dysfunction treated in the participating intensive care units from 2011 to 2015. Test performance for the prediction of Gram-negative bacteremia was assessed by receiver operating curve analysis. Independent effects of specific pathogen groups and foci of infection on PCT concentrations were assessed by linear logistic regression models. RESULTS: Blood cultures (BC) and PCT concentrations had been taken in 4858 of 6561 documented patients. PCT was significantly higher in Gram-negative bacteremia compared to Gram-positive bacteremia or candidemia (p < 0.001). The area under the curve was 0.72 (95% confidence interval 0.71-0.74) for the prediction of Gram-negative bacteremia compared to all other blood culture results including negative blood cultures. The optimized cutoff value was 10 ng/ml (sensitivity 69%, specificity 35%). PCT differed significantly between specific groups of pathogens (p < 0.001) with highest concentrations in Escherichia coli, Streptococcus species and other Enterobacteriaceae. PCT was highest in urogenital followed by abdominal infection and lowest in respiratory infection (p < 0.001). In a linear regression model, Streptococci, E. coli and other Enterobacteriaceae detected from BC were associated with three times higher PCT values. Urogenital or abdominal foci of infection were associated with twofold increased PCT values independent of the pathogen. CONCLUSIONS: Serum PCT concentrations are higher in patients with Gram-negative bacteremia than in patients with Gram-positive bacteremia or candidemia. However, the discriminatory power of this difference is too low to guide therapeutic decisions. Variations in PCT serum concentrations are not determined solely by Gram-negative or Gram-positive bacteria but are also affected by distinct groups of pathogens and different foci of infection. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01187134 . Registered on 23 August 2010.

The use of mid-regional proadrenomedullin to identify disease severity and treatment response to sepsis - a secondary analysis of a large randomised controlled trial.

BACKGROUND: This study assessed the ability of mid-regional proadrenomedullin (MR-proADM) in comparison to conventional biomarkers (procalcitonin (PCT), lactate, C-reactive protein) and clinical scores to identify disease severity in patients with sepsis. METHODS: This is a secondary analysis of a randomised controlled trial in patients with severe sepsis or septic shock across 33 German intensive care units. The association between biomarkers and clinical scores with mortality was assessed by Cox regression analysis, area under the receiver operating characteristic and Kaplan-Meier curves. Patients were stratified into three severity groups (low, intermediate, high) for all biomarkers and scores based on cutoffs with either a 90% sensitivity or specificity. RESULTS: 1089 patients with a 28-day mortality rate of 26.9% were analysed. According to the Sepsis-3 definition, 41.2% and 58.8% fulfilled the criteria for sepsis and septic shock, with respective mortality rates of 20.0% and 32.1%. MR-proADM had the strongest association with mortality across all Sepsis-1 and Sepsis-3 subgroups and could facilitate a more accurate classification of low (e.g. MR-proADM vs. SOFA: N = 265 vs. 232; 9.8% vs. 13.8% mortality) and high (e.g. MR-proADM vs. SOFA: N = 161 vs. 155; 55.9% vs. 41.3% mortality) disease severity. Patients with decreasing PCT concentrations of either ≥ 20% (baseline to day 1) or ≥ 50% (baseline to day 4) but continuously high MR-proADM concentrations had a significantly increased mortality risk (HR (95% CI): 19.1 (8.0-45.9) and 43.1 (10.1-184.0)). CONCLUSIONS: MR-proADM identifies disease severity and treatment response more accurately than established biomarkers and scores, adding additional information to facilitate rapid clinical decision-making and improve personalised sepsis treatment.

Clinical Frailty Scale (CFS) reliably stratifies octogenarians in German ICUs: a multicentre prospective cohort study.

BACKGROUND: In intensive care units (ICU) octogenarians become a routine patients group with aggravated therapeutic and diagnostic decision-making. Due to increased mortality and a reduced quality of life in this high-risk population, medical decision-making a fortiori requires an optimum of risk stratification. Recently, the VIP-1 trial prospectively observed that the clinical frailty scale (CFS) performed well in ICU patients in overall-survival and short-term outcome prediction. However, it is known that healthcare systems differ in the 21 countries contributing to the VIP-1 trial. Hence, our main focus was to investigate whether the CFS is usable for risk stratification in octogenarians admitted to diversified and high tech German ICUs. METHODS: This multicentre prospective cohort study analyses very old patients admitted to 20 German ICUs as a sub-analysis of the VIP-1 trial. Three hundred and eight patients of 80 years of age or older admitted consecutively to participating ICUs. CFS, cause of admission, APACHE II, SAPS II and SOFA scores, use of ICU resources and ICU- and 30-day mortality were recorded. Multivariate logistic regression analysis was used to identify factors associated with 30-day mortality. RESULTS: Patients had a median age of 84 [IQR 82-87] years and a mean CFS of 4.75 (± 1.6 standard-deviation) points. More than half of the patients (53.6%) were classified as frail (CFS ≥ 5). ICU-mortality was 17.3% and 30-day mortality was 31.2%. The cause of admission (planned vs. unplanned), (OR 5.74) and the CFS (OR 1.44 per point increase) were independent predictors of 30-day survival. CONCLUSIONS: The CFS is an easy determinable valuable tool for prediction of 30-day ICU survival in octogenarians, thus, it may facilitate decision-making for intensive care givers in Germany. TRIAL REGISTRATION: The VIP-1 study was retrospectively registered on ClinicalTrials.gov (ID: NCT03134807 ) on May 1, 2017.

Perceived Nonbeneficial Treatment of Patients, Burnout, and Intention to Leave the Job Among ICU Nurses and Junior and Senior Physicians.

OBJECTIVES: Perceiving nonbeneficial treatment is stressful for ICU staff and may be associated with burnout. We aimed to investigate predictors and consequences of perceived nonbeneficial treatment and to compare nurses and junior and senior physicians. DESIGN: Cross-sectional, multicenter paper-pencil survey on personal and work-related characteristics, perceived nonbeneficial treatment, burnout, and intention to leave the job. SETTING: Convenience sample of 23 German ICUs. SUBJECTS: ICU nurses and physicians. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 847 questionnaires were returned (51% response); 778 had complete data for final multivariate analyses. Nonbeneficial treatment was in median perceived "sometimes." Adjusted for covariates, it was perceived more often by nurses and junior physicians (both p ≤ 0.001 in comparison to senior physicians), while emotional exhaustion was highest in junior physicians (p ≤ 0.015 in comparison to senior physicians and nurses), who also had a higher intention to leave than nurses (p = 0.024). Nonbeneficial treatment was predicted by high workload and low quality collaboration with other departments (both p ≤ 0.001). Poor nurse-physician collaboration predicted perception of nonbeneficial treatment among junior physicians and nurses (both p ≤ 0.001) but not among senior physicians (p = 0.753). Nonbeneficial treatment was independently associated with the core burnout dimension emotional exhaustion (p ≤ 0.001), which significantly mediated the effect between nonbeneficial treatment and intention to leave (indirect effect: 0.11 [95% CI, 0.06-0.18]). CONCLUSIONS: Perceiving nonbeneficial treatment is related to burnout and may increase intention to leave. Efforts to reduce perception of nonbeneficial treatment should improve the work environment and should be tailored to the different experiences of nurses and junior and senior physicians.

High-dose intravenous selenium does not improve clinical outcomes in the critically ill: a systematic review and meta-analysis.

BACKGROUND: Selenium (Se) is an essential trace element with antioxidant, anti-inflammatory, and immunomodulatory effects. So far, several randomized clinical trials (RCTs) have demonstrated that parenteral Se may improve clinical outcomes in intensive care unit (ICU) patients. Since publication of our previous systematic review and meta-analysis on antioxidants in the ICU, reports of several trials have been published, including the largest RCT on Se therapy. The purpose of the present systematic review was to update our previous data on intravenous (IV) Se in the critically ill. METHODS: We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials. We included RCTs with parallel groups comparing parenteral Se as single or combined therapy with placebo. Potential trials were evaluated according to specific eligibility criteria, and two reviewers abstracted data from original trials in duplicate independently. Overall mortality was the primary outcome; secondary outcomes were infections, ICU length of stay (LOS), hospital LOS, ventilator days, and new renal dysfunction. RESULTS: A total of 21 RCTs met our inclusion criteria. When the data from these trials were aggregated, IV Se had no effect on mortality (risk ratio [RR] 0.98, 95 % CI 0.90-1.08, P = 0.72, heterogeneity I 2 = 0 %). In addition, when the results of ten trials in which researchers reported on infections were statistically aggregated, there was no significant treatment effect of parenteral Se (RR 0.95, 95 % CI 0.88-1.02, P = 0.15, I 2 = 0 %). There was no positive or negative effect of Se therapy on ICU and hospital LOS, renal function, or ventilator days. CONCLUSIONS: In critically ill patients, IV Se as monotherapy does not improve clinical outcomes.

Impact of compliance with infection management guidelines on outcome in patients with severe sepsis: a prospective observational multi-center study.

INTRODUCTION: Current sepsis guidelines recommend antimicrobial treatment (AT) within one hour after onset of sepsis-related organ dysfunction (OD) and surgical source control within 12 hours. The objective of this study was to explore the association between initial infection management according to sepsis treatment recommendations and patient outcome. METHODS: In a prospective observational multi-center cohort study in 44 German ICUs, we studied 1,011 patients with severe sepsis or septic shock regarding times to AT, source control, and adequacy of AT. Primary outcome was 28-day mortality. RESULTS: Median time to AT was 2.1 (IQR 0.8 - 6.0) hours and 3 hours (-0.1 - 13.7) to surgical source control. Only 370 (36.6%) patients received AT within one hour after OD in compliance with recommendation. Among 422 patients receiving surgical or interventional source control, those who received source control later than 6 hours after onset of OD had a significantly higher 28-day mortality than patients with earlier source control (42.9% versus 26.7%, P <0.001). Time to AT was significantly longer in ICU and hospital non-survivors; no linear relationship was found between time to AT and 28-day mortality. Regardless of timing, 28-day mortality rate was lower in patients with adequate than non-adequate AT (30.3% versus 40.9%, P < 0.001). CONCLUSIONS: A delay in source control beyond 6 hours may have a major impact on patient mortality. Adequate AT is associated with improved patient outcome but compliance with guideline recommendation requires improvement. There was only indirect evidence about the impact of timing of AT on sepsis mortality.

Sepsis and underlying comorbidities in intensive care unit patients : Analysis of the cause of death by different clinicians-a pilot study.

BACKGROUND: There is an ongoing debate as to whether death with sepsis is primarily caused by sepsis or, more often, by the underlying disease. There are no data on the influence of a researcher's background on such an assessment. Therefore, the aim of this analysis was to assess the cause of death in sepsis and the influence of an investigator's professional background on such an assessment. MATERIALS AND METHODS: We performed a retrospective observational cohort study of sepsis patients treated in the medical intensive care unit (ICU) of a tertiary care center. For deceased patients, comorbidities and severity of illness were documented. The cause of death (sepsis or comorbidities or both combined) was independently assessed by four assessors with different professional backgrounds (medical student, senior physician in the medical ICU, anesthesiological intensivist, and senior physician specialized in the predominant comorbidity). RESULTS: In all, 78 of 235 patients died in hospital. Agreement between assessors about cause of death was low (κ 0.37, 95% confidence interval 0.29-0.44). Depending on the assessor, sepsis was the sole cause of death in 6-12% of cases, sepsis and comorbidities in 54-76%, and comorbidities alone in 18-40%. CONCLUSIONS: In a relevant proportion of patients with sepsis treated in the medical ICU, comorbidities contribute significantly to mortality, and death from sepsis without relevant comorbidities is a rare event. Designation of the cause of death in sepsis patients is highly subjective and may be influenced by the professional background of the assessor.

Perceptions of Quality of Interprofessional Collaboration, Staff Well-Being and Nonbeneficial Treatment: A Comparison between Nurses and Physicians in Intensive and Palliative Care.

This study assessed differences in interprofessional collaboration, perception of nonbeneficial care, and staff well-being between critical care and palliative care teams. In six German hospitals, a staff survey was conducted between December 2013 and March 2015 among nurses and physicians in intensive and palliative care units. To allow comparability between unit types, a matching was performed for demographic characteristics of staff. N = 313 critical care and 79 palliative care staff participated, of which 72 each were successfully matched. Critical care nurses perceived the poorest overall quality of collaboration compared with critical care physicians and palliative care physicians and nurses. They also reported less inclusive leadership from attendings and head nurses, and the least collaboration on care decisions with physicians. They were most likely to perceive nonbeneficial care, and they reported the lowest levels of job satisfaction and the highest intention to leave the job. In partial correlations, aspects of high-quality collaboration were associated with less perceived nonbeneficial care and higher staff well-being for both critical care and palliative care staff. Our findings indicate that critical care teams could improve collaboration and enhance well-being, particularly among nurses, by adopting principles of collaborative work culture as established in palliative care.

Serum cytokine dysregulation signatures associated with COVID-19 outcomes in high mortality intensive care unit cohorts across pandemic waves and variants.

The aim of this study was to characterize the systemic cytokine signature of critically ill COVID-19 patients in a high mortality setting aiming to identify biomarkers of severity, and to explore their associations with viral loads and clinical characteristics. We studied two COVID-19 critically ill patient cohorts from a referral centre located in Central Europe. The cohorts were recruited during the pre-alpha/alpha (November 2020 to April 2021) and delta (end of 2021) period respectively. We determined both the serum and bronchoalveolar SARS-CoV-2 viral load and identified the variant of concern (VoC) involved. Using a cytokine multiplex assay, we quantified systemic cytokine concentrations and analyzed their relationship with clinical findings, routine laboratory workup and pulmonary function data obtained during the ICU stay. Patients who did not survive had a significantly higher systemic and pulmonary viral load. Patients infected with the pre-alpha VoC showed a significantly lower viral load in comparison to those infected with the alpha- and delta-variants. Levels of systemic CTACK, M-CSF and IL-18 were significantly higher in non-survivors in comparison to survivors. CTACK correlated directly with APACHE II scores. We observed differences in lung compliance and the association between cytokine levels and pulmonary function, dependent on the VoC identified. An intra-cytokine analysis revealed a loss of correlation in the non-survival group in comparison to survivors in both cohorts. Critically ill COVID-19 patients exhibited a distinct systemic cytokine profile based on their survival outcomes. CTACK, M-CSF and IL-18 were identified as mortality-associated analytes independently of the VoC involved. The Intra-cytokine correlation analysis suggested the potential role of a dysregulated systemic network of inflammatory mediators in severe COVID-19 mortality.

Skin dysbiosis and loss of microbiome site specificity in critically ill patients.

An increasing amount of evidence has linked critical illness with dysbiotic microbiome signatures in different body sites. The disturbance of the indigenous microbiota structures has been further associated with disease severity and outcome and has been suggested to pose an additional risk for complications in intensive care units (ICUs), including hospital-acquired infections. A better understanding of the microbial dysbiosis in critical illness might thus help to develop strategies for the prevention of such complications. While most of the studies addressing microbiome changes in ICU patients have focused on the gut, the lung, or the oral cavity, little is known about the microbial communities on the skin of ICU patients. Since the skin is the outermost organ and the first immune barrier against pathogens, its microbiome might play an important role in the risk management for critically ill patients. This observational study characterizes the skin microbiome in ICU patients covering five different body sites at the time of admission. Our results show a profound dysbiosis on the skin of critically ill patients, which is characterized by a loss of site specificity and an overrepresentation of gut bacteria on all skin sites when compared to a healthy group. This study opens a new avenue for further investigations on the effect of skin dysbiosis in the ICU setting and points out the need of strategies for the management of dysbiosis in critically ill patients.IMPORTANCEUnbalanced gut microbiota in critically ill patients has been associated with poor outcome and complications during the intensive care unit (ICU) stay. Whether the disturbance of the microbial communities in these patients is extensive for other body sites, such as the skin, is largely unknown. The skin not only is the largest organ of the body but also serves as the first immune barrier against potential pathogens. This study characterized the skin microbiota on five different body sites in ICU patients at the time of admission. The observed disturbance of the bacterial communities might help to develop new strategies in the risk management of critically ill patients.