Key summary of German national treatment guidance for hospitalized COVID-19 patients : Key pharmacologic recommendations from a national German living guideline using an Evidence to Decision Framework (last updated 17.05.2021).

PURPOSE: This executive summary of a national living guideline aims to provide rapid evidence based recommendations on the role of drug interventions in the treatment of hospitalized patients with COVID-19. METHODS: The guideline makes use of a systematic assessment and decision process using an evidence to decision framework (GRADE) as recommended standard WHO (2021). Recommendations are consented by an interdisciplinary panel. Evidence analysis and interpretation is supported by the CEOsys project providing extensive literature searches and living (meta-) analyses. For this executive summary, selected key recommendations on drug therapy are presented including the quality of the evidence and rationale for the level of recommendation. RESULTS: The guideline contains 11 key recommendations for COVID-19 drug therapy, eight of which are based on systematic review and/or meta-analysis, while three recommendations represent consensus expert opinion. Based on current evidence, the panel makes strong recommendations for corticosteroids (WHO scale 5-9) and prophylactic anticoagulation (all hospitalized patients with COVID-19) as standard of care. Intensified anticoagulation may be considered for patients with additional risk factors for venous thromboembolisms (VTE) and a low bleeding risk. The IL-6 antagonist tocilizumab may be added in case of high supplemental oxygen requirement and progressive disease (WHO scale 5-6). Treatment with nMABs may be considered for selected inpatients with an early SARS-CoV-2 infection that are not hospitalized for COVID-19. Convalescent plasma, azithromycin, ivermectin or vitamin D3 should not be used in COVID-19 routine care. CONCLUSION: For COVID-19 drug therapy, there are several options that are sufficiently supported by evidence. The living guidance will be updated as new evidence emerges.

Systemic calcitonin gene-related peptide receptor antagonism decreases survival in a porcine model of polymicrobial sepsis: blinded randomised controlled trial.

BACKGROUND: Calcitonin gene-related peptide (CGRP) and procalcitonin, which are overexpressed in sepsis, exert distinct immunomodulatory effects mediated through the CGRP receptor. The CGRP receptor antagonist olcegepant improves survival in murine sepsis. This study evaluated whether CGRP receptor antagonism is similarly beneficial in a porcine model of polymicrobial sepsis. METHODS: We conducted a prospective randomised, controlled, investigator-blinded trial in adult pigs of either sex, that were anaesthetised and ventilated before sepsis was induced by polymicrobial (autologous) faecal peritonitis. After the onset of early septic shock (systolic blood pressure <90 mm Hg or >10% decline from baseline MAP), pigs were resuscitated (i.v. fluid/antibiotics/vasopressors) and randomised to receive either i.v. olcegepant (n=8) or vehicle control (n=8). The primary outcome was time to death, euthanasia required up to 72 h after surgery (according to predefined severe cardiorespiratory failure), or both. Secondary outcomes included haemodynamic changes, and systemic as well as organ inflammation (mRNA expression). RESULTS: Septic shock developed 8.7 h (inter-quartile range, 5.8-11.1 h) after the onset of faecal peritonitis. Olcegepant worsened survival, with 6/8 pigs randomised to the control group surviving 72.0 h (50.9-72.0 h), compared with 3/8 pigs receiving olcegepant surviving 51.3 h (12.5-72.0 h; P=0.01). At 48 h, lower MAP and higher cardiac output occurred in pigs receiving olcegepant. Cardiac, hepatic, and renal injury was not different between pigs randomised to receive olcegepant or vehicle. Olcegepant reduced mRNA expression of several inflammation-related cytokines and CD68+ macrophages in liver but not in lung tissue. CONCLUSIONS: CGRP receptor antagonism with olcegepant was not beneficial in this porcine model of polymicrobial sepsis, which closely mimics human sepsis.

Influence of Ingestion of Game Meat on Blood Concentration of Lead in Southern Germany: A Pilot Study.

Consumption of game meat may exert additional lead exposure with potential health risks. The purpose of the present pilot study was to determine blood lead concentration in game meat and no game meat consumers in southern Germany. Concentration of lead in blood (µg·L- 1) was significantly higher in game meat consumers (n = 190; 21.3 [20.0; 29.7]) compared to study participants consuming no game meat (n = 74; 20.0 [20.0; 20.0], p < 0.0001). In study participants with no game meat consumption, blood lead concentration was significantly higher in those who perform active hunting (80.3 [50.5; 110.0]) as well as active shooting (80.3 [50.5; 110.0]) than in those with no hunting or shooting activities (20.0 [20.0; 20.0], p < 0.01). In conclusion, game meat consumers as well as active hunters and shooters should take in to account their potential for an increased lead exposure and the corresponding health risks.

Development of a novel global rating scale for objective structured assessment of technical skills in an emergency medical simulation training.

BACKGROUND: Medical simulation trainings lead to an improvement in patient care by increasing technical and non-technical skills, procedural confidence and medical knowledge. For structured simulation-based trainings, objective assessment tools are needed to evaluate the performance during simulation and the learning progress. In surgical education, objective structured assessment of technical skills (OSATS) are widely used and validated. However, in emergency medicine and anesthesia there is a lack of validated assessment tools for technical skills. Thus, the aim of the present study was to develop and validate a novel Global Rating Scale (GRS) for emergency medical simulation trainings. METHODS: Following the development of the GRS, 12 teams of different experience in emergency medicine (4th year medical students, paramedics, emergency physicians) were involved in a pre-hospital emergency medicine simulation scenario and assessed by four independent raters. Subsequently, interrater reliability and construct validity of the GRS were analyzed. Moreover, the results of the GRS were cross-checked with a task specific check list. Data are presented as median (minimum; maximum). RESULTS: The GRS consists of ten items each scored on a 5-point Likert scale yielding a maximum of 50 points. The median score achieved by novice teams was 22.75 points (17;30), while experts scored 39.00 points (32;47). The GRS overall scores significantly discriminated between student-guided teams and expert teams of emergency physicians (p = 0.005). Interrater reliability for the GRS was high with a Kendall's coefficient of concordance W ranging from 0.64 to 0.90 in 9 of 10 items and 0.88 in the overall score. CONCLUSION: The GRS represents a promising novel tool to objectively assess technical skills in simulation training with high construct validity and interrater reliability in this pilot study.

Surgical tracheostomy in a cohort of COVID-19 patients.

BACKGROUND: One of the main symptoms of severe infection with the new coronavirus­2 (SARS-CoV-2) is hypoxemic respiratory failure because of viral pneumonia with the need for mechanical ventilation. Prolonged mechanical ventilation may require a tracheostomy, but the increased risk for contamination is a matter of considerable debate. OBJECTIVE: Evaluation of safety and effects of surgical tracheostomy on ventilation parameters and outcome in patients with COVID-19. STUDY DESIGN: Retrospective observational study between March 27 and May 18, 2020, in a single-center coronavirus disease-designated ICU at a tertiary care German hospital. PATIENTS: Patients with COVID-19 were treated with open surgical tracheostomy due to severe hypoxemic respiratory failure requiring mechanical ventilation. MEASUREMENTS: Clinical and ventilation data were obtained from medical records in a retrospective manner. RESULTS: A total of 18 patients with confirmed SARS-CoV­2 infection and surgical tracheostomy were analyzed. The age range was 42-87 years. All patients received open tracheostomy between 2-16 days after admission. Ventilation after tracheostomy was less invasive (reduction in PEAK and positive end-expiratory pressure [PEEP]) and lung compliance increased over time after tracheostomy. Also, sedative drugs could be reduced, and patients had a reduced need of norepinephrine to maintain hemodynamic stability. Six of 18 patients died. All surgical staff were equipped with N99-masks and facial shields or with powered air-purifying respirators (PAPR). CONCLUSION: Our data suggest that open surgical tracheostomy can be performed without severe complications in patients with COVID-19. Tracheostomy may reduce invasiveness of mechanical ventilation and the need for sedative drugs and norepinehprine. Recommendations for personal protective equipment (PPE) for surgical staff should be followed when PPE is available to avoid contamination of the personnel.

Effects of sodium thiosulfate (Na2S2O3) during resuscitation from hemorrhagic shock in swine with preexisting atherosclerosis.

Controversial data are available on hydrogen sulfide (H2S) during hemorrhage and resuscitation, depending on timing, dosing, mode of application, and the H2S donor used. Sodium thiosulfate (Na2S2O3) is a recognized drug devoid of major side effects, which attenuated murine acute lung injury and cerebral ischemia/reperfusion injury. Therefore, we tested the hypothesis whether Na2S2O3 would mitigate organ dysfunction in porcine hemorrhage-and-resuscitation. We studied animals with pre-existing coronary artery disease because of the reduced coronary arterial expression of the H2S producing enzyme cystathionine-γ-lyase (CSE) in this prospective, randomized, controlled, blinded experimental study. 20 anesthetized and instrumented pigs underwent 3 h of hemorrhage (removal of 30 % of the blood volume and subsequent titration of mean arterial pressure to 40 mmHg). Resuscitation (72 h) comprised re-transfusion of shed blood, crystalloids, and continuous i.v. norepinephrine. Animals randomly received vehicle or Na2S2O3 (0.1 g·kg-1 h-1) for 24 h. Before, at the end of and every 24 h after shock, hemodynamics, metabolism, blood gases, lung, heart, kidney, and liver function and injury were evaluated together with cytokines and parameters of oxidative and nitrosative stress. Immediate post mortem lung, kidney, heart, and liver specimen were analyzed for marker proteins of inflammation and oxidative and nitrosative stress and mitochondrial respiratory activity in the heart, kidney, and liver. Immuno-histochemical analysis comprised lung extra-vascular albumin accumulation, nitrotyrosine formation, and CSE and glucocorticoid receptor (GCR) expression. Na2S2O3 significantly attenuated shock-induced impairment of lung mechanics and gas exchange (plateau and positive end-expiratory pressure at 72 h p = 0.0006/p = 0.0264; Horovitz index at 48 h p = 0.0261), which coincided with a higher tissue GCR expression (p = 0.0415). During resuscitation from hemorrhagic shock Na2S2O3 attenuated shock-induced acute lung injury in co-morbid swine, most likely due to a GCR expression related mechanism.

Impaired hypoxic pulmonary vasoconstriction in a mouse model of Leigh syndrome.

Hypoxic pulmonary vasoconstriction (HPV) is a physiological vasomotor response that maintains systemic oxygenation by matching perfusion to ventilation during alveolar hypoxia. Although mitochondria appear to play an essential role in HPV, the impact of mitochondrial dysfunction on HPV remains incompletely defined. Mice lacking the mitochondrial complex I (CI) subunit Ndufs4 ( Ndufs4-/-) develop a fatal progressive encephalopathy and serve as a model for Leigh syndrome, the most common mitochondrial disease in children. Breathing normobaric 11% O2 prevents neurological disease and improves survival in Ndufs4-/- mice. In this study, we found that either genetic Ndufs4 deficiency or pharmacological inhibition of CI using piericidin A impaired the ability of left mainstem bronchus occlusion (LMBO) to induce HPV. In mice breathing air, the partial pressure of arterial oxygen during LMBO was lower in Ndufs4-/- and in piericidin A-treated Ndufs4+/+ mice than in respective controls. Impairment of HPV in Ndufs4-/- mice was not a result of nonspecific dysfunction of the pulmonary vascular contractile apparatus or pulmonary inflammation. In Ndufs4-deficient mice, 3 wk of breathing 11% O2 restored HPV in response to LMBO. When compared with Ndufs4-/- mice breathing air, chronic hypoxia improved systemic oxygenation during LMBO. The results of this study show that, when breathing air, mice with a congenital Ndufs4 deficiency or chemically inhibited CI function have impaired HPV. Our study raises the possibility that patients with inborn errors of mitochondrial function may also have defects in HPV.

Development of a portable mini-generator to safely produce nitric oxide for the treatment of infants with pulmonary hypertension.

OBJECTIVES: To test the safety of a novel miniaturized device that produces nitric oxide (NO) from air by pulsed electrical discharge, and to demonstrate that the generated NO can be used to vasodilate the pulmonary vasculature in rabbits with chemically-induced pulmonary hypertension. STUDY DESIGN: A miniature NO (mini-NO) generator was tested for its ability to produce therapeutic levels (20-80 parts per million (ppm)) of NO, while removing potentially toxic gases and metal particles. We studied healthy 6-month-old New Zealand rabbits weighing 3.4 ±â€¯0.4 kg (mean ±â€¯SD, n = 8). Pulmonary hypertension was induced by chemically increasing right ventricular systolic pressure to 28-30 mmHg. The mini-NO generator was placed near the endotracheal tube. Production of NO was triggered by a pediatric airway flowmeter during the first 0.5 s of inspiration. RESULTS: In rabbits with acute pulmonary hypertension, the mini-NO generator produced sufficient NO to induce pulmonary vasodilation. Potentially toxic nitrogen dioxide (NO2) and ozone (O3) were removed by the Ca(OH)2 scavenger. Metallic particles, released from the electrodes by the electric plasma, were removed by a 0.22 µm filter. While producing 40 ppm NO, the mini-NO generator was cooled by a flow of air (70 ml/min) and the external temperature of the housing did not exceed 31 °C. CONCLUSIONS: The mini-NO generator safely produced therapeutic levels of NO from air. The mini-NO generator is an effective and economical approach to producing NO for treating neonatal pulmonary hypertension and will increase the accessibility and therapeutic uses of life-saving NO therapy worldwide.

Effects of Hyperoxia During Resuscitation From Hemorrhagic Shock in Swine With Preexisting Coronary Artery Disease.

OBJECTIVES: Investigation of the effects of hyperoxia during resuscitation from hemorrhagic shock in swine with preexisting coronary artery disease. DESIGN: Prospective, controlled, randomized trial. SETTING: University animal research laboratory. SUBJECTS: Nineteen hypercholesterolemic pigs with preexisting coronary artery disease. INTERVENTIONS: Anesthetized, mechanically ventilated, and surgically instrumented pigs underwent 3 hours of hemorrhagic shock (removal of 30% of the calculated blood volume and subsequent titration of mean arterial blood pressure ≈40 mm Hg). Postshock resuscitation (48 hr) comprised retransfusion of shed blood, crystalloids (balanced electrolyte solution), and norepinephrine support. Pigs were randomly assigned to "control" (FIO2 0.3, adjusted for arterial oxygen saturation ≥ 90%) and "hyperoxia" (FIO2 1.0 for 24 hr) groups. MEASUREMENTS AND MAIN RESULTS: Before, at the end of shock and every 12 hours of resuscitation, datasets comprising hemodynamics, calorimetry, blood gases, cytokines, and cardiac and renal function were recorded. Postmortem, organs were sampled for immunohistochemistry, western blotting, and mitochondrial high-resolution respirometry. Survival rates were 50% and 89% in the control and hyperoxia groups, respectively (p = 0.077). Apart from higher relaxation constant τ at 24 hours, hyperoxia did not affect cardiac function. However, troponin values were lower (2.2 [0.9-6.2] vs 6.9 [4.8-9.8] ng/mL; p < 0.05) at the end of the experiment. Furthermore, hyperoxia decreased cardiac 3-nitrotyrosine formation and increased inducible nitric oxide synthase expression. Plasma creatinine values were lower in the hyperoxia group during resuscitation coinciding with significantly improved renal mitochondrial respiratory capacity and lower 3-nitrotyrosine formation. CONCLUSIONS: Hyperoxia during resuscitation from hemorrhagic shock in swine with preexisting coronary artery disease reduced renal dysfunction and cardiac injury, potentially resulting in improved survival, most likely due to increased mitochondrial respiratory capacity and decreased oxidative and nitrosative stress. Compared with our previous study, the present results suggest a higher benefit of hyperoxia in comorbid swine due to an increased susceptibility to hemorrhagic shock.

Sensitivity to Sevoflurane anesthesia is decreased in mice with a congenital deletion of Guanylyl Cyclase-1 alpha.

BACKGROUND: Volatile anesthetics increase levels of the neurotransmitter nitric oxide (NO) and the secondary messenger molecule cyclic guanosine monophosphate (cGMP) in the brain. NO activates the enzyme guanylyl cyclase (GC) to produce cGMP. We hypothesized that the NO-GC-cGMP pathway contributes to anesthesia-induced unconsciousness. METHODS: Sevoflurane-induced loss and return of righting reflex (LORR and RORR, respectively) were studied in wild-type mice (WT) and in mice congenitally deficient in the GC-1α subunit (GC-1-/- mice). Spatial distributions of GC-1α and the GC-2α subunit in the brain were visualized by in situ hybridization. Brain cGMP levels were measured in WT and GC-1-/- mice after inhaling oxygen with or without 1.2% sevoflurane for 20 min. RESULTS: Higher concentrations of sevoflurane were required to induce LORR in GC-1-/- mice than in WT mice (1.5 ± 0.1 vs. 1.1 ± 0.2%, respectively, n = 14 and 14, P < 0.0001). Similarly, RORR occurred at higher concentrations of sevoflurane in GC-1-/- mice than in WT mice (1.0 ± 0.1 vs. 0.8 ± 0.1%, respectively, n = 14 and 14, P < 0.0001). Abundant GC-1α and GC-2α mRNA expression was detected in the cerebral cortex, medial habenula, hippocampus, and cerebellum. Inhaling 1.2% sevoflurane for 20 min increased cGMP levels in the brains of WT mice from 2.6 ± 2.0 to 5.5 ± 3.7 pmol/mg protein (n = 13 and 10, respectively, P = 0.0355) but not in GC-1-/- mice. CONCLUSION: Congenital deficiency of GC-1α abolished the ability of sevoflurane anesthesia to increase cGMP levels in the whole brain, and increased the concentration of sevoflurane required to induce LORR. Impaired NO-cGMP signaling raises the threshold for producing sevoflurane-induced unconsciousness in mice.

Soluble epoxide hydrolase deficiency or inhibition enhances murine hypoxic pulmonary vasoconstriction after lipopolysaccharide challenge.

Hypoxic pulmonary vasoconstriction (HPV) is the response of the pulmonary vasculature to low levels of alveolar oxygen. HPV improves systemic arterial oxygenation by matching pulmonary perfusion to ventilation during alveolar hypoxia and is impaired in lung diseases such as the acute respiratory distress syndrome (ARDS) and in experimental models of endotoxemia. Epoxyeicosatrienoic acids (EETs) are pulmonary vasoconstrictors, which are metabolized to less vasoactive dihydroxyeicosatrienoic acids (DHETs) by soluble epoxide hydrolase (sEH). We hypothesized that pharmacological inhibition or a congenital deficiency of sEH in mice would reduce the metabolism of EETs and enhance HPV in mice after challenge with lipopolysaccharide (LPS). HPV was assessed 22 h after intravenous injection of LPS by measuring the percentage increase in the pulmonary vascular resistance of the left lung induced by left mainstem bronchial occlusion (LMBO). After LPS challenge, HPV was impaired in sEH+/+, but not in sEH-/- mice or in sEH+/+ mice treated acutely with a sEH inhibitor. Deficiency or pharmacological inhibition of sEH protected mice from the LPS-induced decrease in systemic arterial oxygen concentration (PaO2 ) during LMBO. In the lungs of sEH-/- mice, the LPS-induced increase in DHETs and cytokines was attenuated. Deficiency or pharmacological inhibition of sEH protects mice from LPS-induced impairment of HPV and improves the PaO2 after LMBO. After LPS challenge, lung EET degradation and cytokine expression were reduced in sEH-/- mice. Inhibition of sEH might prove to be an effective treatment for ventilation-perfusion mismatch in lung diseases such as ARDS.

Effects of Hyperoxia and Mild Therapeutic Hypothermia During Resuscitation From Porcine Hemorrhagic Shock.

OBJECTIVE: Hemorrhagic shock-induced tissue hypoxia induces hyperinflammation, ultimately causing multiple organ failure. Hyperoxia and hypothermia can attenuate tissue hypoxia due to increased oxygen supply and decreased demand, respectively. Therefore, we tested the hypothesis whether mild therapeutic hypothermia and hyperoxia would attenuate postshock hyperinflammation and thereby organ dysfunction. DESIGN: Prospective, controlled, randomized study. SETTING: University animal research laboratory. SUBJECTS: Thirty-six Bretoncelles-Meishan-Willebrand pigs of either gender. INTERVENTIONS: After 4 hours of hemorrhagic shock (removal of 30% of the blood volume, subsequent titration of mean arterial pressure at 35 mm Hg), anesthetized and instrumented pigs were randomly assigned to "control" (standard resuscitation: retransfusion of shed blood, fluid resuscitation, norepinephrine titrated to maintain mean arterial pressure at preshock values, mechanical ventilation titrated to maintain arterial oxygen saturation > 90%), "hyperoxia" (standard resuscitation, but FIO2, 1.0), "hypothermia" (standard resuscitation, but core temperature 34°C), or "combi" (hyperoxia plus hypothermia) (n = 9 each). MEASUREMENTS AND MAIN RESULTS: Before, immediately at the end of and 12 and 22 hours after hemorrhagic shock, we measured hemodynamics, blood gases, acid-base status, metabolism, organ function, cytokine production, and coagulation. Postmortem kidney specimen were taken for histological evaluation, immunohistochemistry (nitrotyrosine, cystathionine γ-lyase, activated caspase-3, and extravascular albumin), and immunoblotting (nuclear factor-κB, hypoxia-inducible factor-1α, heme oxygenase-1, inducible nitric oxide synthase, B-cell lymphoma-extra large, and protein expression of the endogenous nuclear factor-κB inhibitor). Although hyperoxia alone attenuated the postshock hyperinflammation and thereby tended to improve visceral organ function, hypothermia and combi treatment had no beneficial effect. CONCLUSIONS: During resuscitation from near-lethal hemorrhagic shock, hyperoxia attenuated hyperinflammation, and thereby showed a favorable trend toward improved organ function. The lacking efficacy of hypothermia was most likely due to more pronounced barrier dysfunction with vascular leakage-induced circulatory failure.

Exposure of Stored Packed Erythrocytes to Nitric Oxide Prevents Transfusion-associated Pulmonary Hypertension.

BACKGROUND: Transfusion of packed erythrocytes stored for a long duration is associated with increased pulmonary arterial pressure and vascular resistance. Prolonged storage decreases erythrocyte deformability, and older erythrocytes are rapidly removed from the circulation after transfusion. The authors studied whether treating stored packed ovine erythrocytes with NO before transfusion could prevent pulmonary vasoconstriction, enhance erythrocyte deformability, and prolong erythrocyte survival after transfusion. METHODS: Ovine leukoreduced packed erythrocytes were treated before transfusion with either NO gas or a short-lived NO donor. Sheep were transfused with autologous packed erythrocytes, which were stored at 4°C for either 2 ("fresh blood") or 40 days ("stored blood"). Pulmonary and systemic hemodynamic parameters were monitored before, during, and after transfusion. Transfused erythrocytes were labeled with biotin to measure their circulating lifespan. Erythrocyte deformability was assessed before and after NO treatment using a microfluidic device. RESULTS: NO treatment improved the deformability of stored erythrocytes and increased the number of stored erythrocytes circulating at 1 and 24 h after transfusion. NO treatment prevented transfusion-associated pulmonary hypertension (mean pulmonary arterial pressure at 30 min of 21 ± 1 vs. 15 ± 1 mmHg in control and NO-treated packed erythrocytes, P < 0.0001). Washing stored packed erythrocytes before transfusion did not prevent pulmonary hypertension. CONCLUSIONS: NO treatment of stored packed erythrocytes before transfusion oxidizes cell-free oxyhemoglobin to methemoglobin, prevents subsequent NO scavenging in the pulmonary vasculature, and limits pulmonary hypertension. NO treatment increases erythrocyte deformability and erythrocyte survival after transfusion. NO treatment might provide a promising therapeutic approach to prevent pulmonary hypertension and extend erythrocyte survival.

Cigarette smoke exposure reduces hemorrhagic shock induced circulatory dysfunction in mice with attenuated glucocorticoid receptor function.

Introduction: We previously showed that attenuated glucocorticoid receptor (GR) function in mice (GRdim/dim) aggravates systemic hypotension and impairs organ function during endotoxic shock. Hemorrhagic shock (HS) causes impaired organ perfusion, which leads to tissue hypoxia and inflammation with risk of organ failure. Lung co-morbidities like chronic obstructive pulmonary disease (COPD) can aggravate tissue hypoxia via alveolar hypoxia. The most common cause for COPD is cigarette smoke (CS) exposure. Therefore, we hypothesized that affecting GR function in mice (GRdim/dim) and pre-traumatic CS exposure would further impair hemodynamic stability and organ function after HS. Methods: After 3 weeks of CS exposure, anesthetized and mechanically ventilated GRdim/dim and GR+/+ mice underwent pressure-controlled HS for 1h via blood withdrawal (mean arterial pressure (MAP) 35mmHg), followed by 4h of resuscitation with re-transfusion of shed blood, colloid fluid infusion and, if necessary, continuous intravenous norepinephrine. Acid-base status and organ function were assessed together with metabolic pathways. Blood and organs were collected at the end of the experiment for analysis of cytokines, corticosterone level, and mitochondrial respiratory capacity. Data is presented as median and interquartile range. Results: Nor CS exposure neither attenuated GR function affected survival. Non-CS GRdim/dim mice had a higher need of norepinephrine to keep target hemodynamics compared to GR+/+ mice. In contrast, after CS exposure norepinephrine need did not differ significantly between GRdim/dim and GR+/+ mice. Non-CS GRdim/dim mice presented with a lower pH and increased blood lactate levels compared to GR+/+ mice, but not CS exposed mice. Also, higher plasma concentrations of some pro-inflammatory cytokines were observed in non-CS GRdim/dim compared to GR+/+ mice, but not in the CS group. With regards to metabolic measurements, CS exposure led to an increased lipolysis in GRdim/dim compared to GR+/+ mice, but not in non-CS exposed animals. Conclusion: Whether less metabolic acidosis or increased lipolysis is the reason or the consequence for the trend towards lower catecholamine need in CS exposed GRdim/dim mice warrants further investigation.

Impaired Glucocorticoid Receptor Signaling Aggravates Lung Injury after Hemorrhagic Shock.

We previously showed that attenuated lung injury after hemorrhagic shock (HS) coincided with enhanced levels of the glucocorticoid (GC) receptor (GR) in lung tissue of swine. Here, we investigated the effects of impaired GR signaling on the lung during resuscitated HS using a dysfunctional GR mouse model (GRdim/dim). In a mouse intensive care unit, HS led to impaired lung mechanics and aggravated lung inflammation in GRdim/dim mice compared to wildtype mice (GR+/+). After HS, high levels of the pro-inflammatory and pro-apoptotic transcription factor STAT1/pSTAT1 were found in lung samples from GRdim/dim mice. Lungs of GRdim/dim mice revealed apoptosis, most likely as consequence of reduced expression of the lung-protective Angpt1 compared to GR+/+ after HS. RNA-sequencing revealed increased expression of pro-apoptotic and cytokine-signaling associated genes in lung tissue of GRdim/dim mice. Furthermore, high levels of pro-inflammatory cytokines and iNOS were found in lungs of GRdim/dim mice. Our results indicate impaired repression of STAT1/pSTAT1 due to dysfunctional GR signaling in GRdim/dim mice, which leads to increased inflammation and apoptosis in the lungs. These data highlight the crucial role of functional GR signaling to attenuate HS-induced lung damage.

Effects of Acute Subdural Hematoma-Induced Brain Injury On Energy Metabolism in Peripheral Blood Mononuclear Cells.

ABSTRACT: In activated immune cells, differentiation and function are determined by cell type-specific modifications of metabolic patterns. After traumatic brain injury both immune cell activation and suppression were reported. Therefore, we sought to explore immune cell energy metabolism in a long-term, resuscitated porcine model of acute subdural hematoma (ASDH)-induced acute brain injury devoid of impaired systemic hemodynamics and oxygen transport.Before and up to 50 h after induction of ASDH, peripheral blood mononuclear cells (PBMCs) were separated by density gradient centrifugation, and cell metabolism was analyzed using high-resolution respirometry for mitochondrial respiration and electron spin resonance for reactive oxygen species production. After incubation with stable isotope-labeled 1,2-13C2-glucose or 13C5-glutamine, distinct labeling patterns of intermediates of glycolysis or tricarboxylic acid (TCA) cycle and 13CO2 production were measured by gas chromatography-mass spectroscopy. Principal component analysis was followed by a varimax rotation on the covariance across all measured variables and all measured time points.After ASDH induction, average PBMC metabolic activity remained unaffected, possibly because strict adherence to intensive care unit guidelines limited trauma to ASDH induction without any change in parameters of systemic hemodynamics, oxygen transport, and whole-body metabolism. Despite decreased glycolytic activity fueling the TCA cycle, the principal component analysis indicated a cell type-specific activation pattern with biosynthetic and proliferative characteristics.

Impact of downstream effects of glucocorticoid receptor dysfunction on organ function in critical illness-associated systemic inflammation.

Glucocorticoids (GCs) are stress hormones that regulate developmental and physiological processes and are among the most potent anti-inflammatory drugs to suppress chronic and acute inflammation. GCs act through the glucocorticoid receptor (GR), a ubiquitously expressed ligand-activated transcription factor, which translocates into the nucleus and can act via two different modes, as a GR monomer or as a GR dimer. These two modes of action are not clearly differentiated in practice and may lead to completely different therapeutic outcomes. Detailed aspects of GR mechanisms are often not taken into account when GCs are used in different clinical scenarios. Patients, with critical illness-related corticosteroid insufficiency, treated with natural or synthetic GCs are still missing a clearly defined therapeutic strategy. This review discusses the different modes of GR function and its importance on organ function in vivo.

H2S in acute lung injury: a therapeutic dead end(?).

This review addresses the plausibility of hydrogen sulfide (H2S) therapy for acute lung injury (ALI) and circulatory shock, by contrasting the promising preclinical results to the present clinical reality. The review discusses how the narrow therapeutic window and width, and potentially toxic effects, the route, dosing, and timing of administration all have to be balanced out very carefully. The development of standardized methods to determine in vitro and in vivo H2S concentrations, and the pharmacokinetics and pharmacodynamics of H2S-releasing compounds is a necessity to facilitate the safety of H2S-based therapies. We suggest the potential of exploiting already clinically approved compounds, which are known or unknown H2S donors, as a surrogate strategy.