The Lipid Intensive Drug Therapy for Sepsis Phase II Pilot Clinical Trial.

OBJECTIVES: Low cholesterol levels in early sepsis patients are associated with mortality. We sought to test if IV lipid emulsion administration to sepsis patients with low cholesterol levels would prevent a decline or increase total cholesterol levels at 48 hours. DESIGN: Phase II, adaptive, randomized pilot clinical trial powered for 48 patients. SETTING: Emergency department or ICU of an academic medical center. PATIENTS: Sepsis patients (first 24 hr) with Sequential Organ Failure Assessment greater than or equal to 4 or shock. INTERVENTIONS: Patients meeting study criteria, including screening total cholesterol levels less than or equal to 100 mg/dL or high-density lipoprotein cholesterol (HDL-C) + low-density lipoprotein cholesterol (LDL-C) less than or equal to 70 mg/dL, were randomized to receive one of three doses of lipid emulsion administered twice in 48 hours or no drug (controls). The primary endpoint was a change in serum total cholesterol (48 hr - enrollment) between groups. MEASUREMENTS AND MAIN RESULTS: Forty-nine patients were enrolled and randomized. Two patients randomized to lipid emulsion were withdrawn before drug administration. Data for 24 control patients and 23 lipid emulsion patients were analyzed. The mean change in total cholesterol from enrollment to 48 hours was not different between groups and was 5 mg/dL ( sd 20) for lipid emulsion patients, and 2 mg/dL ( sd 18) for control patients ( p = 0.62). The mean changes in HDL-C and LDL-C were similar between groups. Mean change in triglycerides was elevated in lipid emulsion patients (61 mg/dL, sd 87) compared with controls (20 mg/dL, sd 70, p = 0.086). The 48-hour change in SOFA score was -2 (interquartile range [IQR] -4, -1) for control patients and -2 (IQR -3, 0) for lipid emulsion patients ( p = 0.46). CONCLUSIONS: Administration of IV lipid emulsion to early sepsis patients with low cholesterol levels did not influence change in cholesterol levels from enrollment to 48 hours.

HDL and persistent inflammation immunosuppression and catabolism syndrome.

PURPOSE OF REVIEW: This study reviews the mechanisms of HDL cholesterol immunomodulation in the context of the mechanisms of chronic inflammation and immunosuppression causing persistent inflammation, immunosuppression and catabolism syndrome (PICS) and describes potential therapies and gaps in current research. RECENT FINDINGS: Low HDL cholesterol is predictive of acute sepsis severity and outcome. Recent research has indicated apolipoprotein is a prognostic indicator of long-term outcomes. The pathobiologic mechanisms of PICS have been elucidated in the past several years. Recent research of the interaction of HDL pathways in related chronic inflammatory diseases may provide insights into further mechanisms and therapeutic targets. SUMMARY: HDL significantly influences innate and adaptive immune pathways relating to chronic disease and inflammation. Further research is needed to better characterize these interactions in the setting of PICS.

A hypolipoprotein sepsis phenotype indicates reduced lipoprotein antioxidant capacity, increased endothelial dysfunction and organ failure, and worse clinical outcomes.

OBJECTIVE: Approximately one-third of sepsis patients experience poor outcomes including chronic critical illness (CCI, intensive care unit (ICU) stay > 14 days) or early death (in-hospital death within 14 days). We sought to characterize lipoprotein predictive ability for poor outcomes and contribution to sepsis heterogeneity. DESIGN: Prospective cohort study with independent replication cohort. SETTING: Emergency department and surgical ICU at two hospitals. PATIENTS: Sepsis patients presenting within 24 h. METHODS: Measures included cholesterol levels (total cholesterol, high density lipoprotein cholesterol [HDL-C], low density lipoprotein cholesterol [LDL-C]), triglycerides, paraoxonase-1 (PON-1), and apolipoprotein A-I (Apo A-I) in the first 24 h. Inflammatory and endothelial markers, and sequential organ failure assessment (SOFA) scores were also measured. LASSO selection assessed predictive ability for outcomes. Unsupervised clustering was used to investigate the contribution of lipid variation to sepsis heterogeneity. MEASUREMENTS AND MAIN RESULTS: 172 patients were enrolled. Most (~ 67%, 114/172) rapidly recovered, while ~ 23% (41/172) developed CCI, and ~ 10% (17/172) had early death. ApoA-I, LDL-C, mechanical ventilation, vasopressor use, and Charlson Comorbidity Score were significant predictors of CCI/early death in LASSO models. Unsupervised clustering yielded two discernible phenotypes. The Hypolipoprotein phenotype was characterized by lower lipoprotein levels, increased endothelial dysfunction (ICAM-1), higher SOFA scores, and worse clinical outcomes (45% rapid recovery, 40% CCI, 16% early death; 28-day mortality, 21%). The Normolipoprotein cluster patients had higher cholesterol levels, less endothelial dysfunction, lower SOFA scores and better outcomes (79% rapid recovery, 15% CCI, 6% early death; 28-day mortality, 15%). Phenotypes were validated in an independent replication cohort (N = 86) with greater sepsis severity, which similarly demonstrated lower HDL-C, ApoA-I, and higher ICAM-1 in the Hypolipoprotein cluster and worse outcomes (46% rapid recovery, 23% CCI, 31% early death; 28-day mortality, 42%). Normolipoprotein patients in the replication cohort had better outcomes (55% rapid recovery, 32% CCI, 13% early death; 28-day mortality, 28%) Top features for cluster discrimination were HDL-C, ApoA-I, total SOFA score, total cholesterol level, and ICAM-1. CONCLUSIONS: Lipoproteins predicted poor sepsis outcomes. A Hypolipoprotein sepsis phenotype was identified and characterized by lower lipoprotein levels, increased endothelial dysfunction (ICAM-1) and organ failure, and worse clinical outcomes.

Quantitative and Qualitative Assessments of Cholesterol Association With Bacterial Infection Type in Sepsis and Septic Shock.

BACKGROUND: Reduced cholesterol levels are associated with increased organ failure and mortality in sepsis. Cholesterol levels may vary by infection type (gram negative vs positive), possibly reflecting differences in cholesterol-mediated bacterial clearance. METHODS: This was a secondary analysis of a combined data set of 2 prospective cohort studies of adult patients meeting Sepsis-3 criteria. Infection types were classified as gram negative, gram positive, or culture negative. We investigated quantitative (levels) and qualitative (dysfunctional high-density lipoprotein [HDL]) cholesterol differences. We used multivariable logistic regression to control for disease severity. RESULTS: Among 171 patients with sepsis, infections were gram negative in 67, gram positive in 46, and culture negative in 47. Both gram-negative and gram-positive infections occurred in 11 patients. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and HDL cholesterol (HDL-C) levels were lower for culture-positive sepsis at enrollment (TC, P < .001; LDL-C, P < .001; HDL-C, P = .011) and persisted after controlling for disease severity. Similarly, cholesterol levels were lower among culture-positive patients at 48 hours (TC, P = .012; LDL-C, P = .029; HDL-C, P = .002). Triglyceride (TG) levels were lower at enrollment (P =.033) but not at 48 hours (P = .212). There were no differences in dysfunctional HDL. Among bacteremic patients, cholesterol levels were lower at enrollment (TC, P = .010; LDL-C, P = .010; HDL-C, P ≤ .001; TG, P = .005) and at 48 hours (LDL-C, P = .027; HDL-C, P < .001; TG, P = .020), except for 48 hour TC (P = .051). In the bacteremia subgroup, enrollment TC and LDL-C were lower for gram-negative versus gram-positive infections (TC, P = .039; LDL-C, P = .023). CONCLUSION: Cholesterol levels are significantly lower among patients with culture-positive sepsis and bacteremia.

Development of a Simple Sequential Organ Failure Assessment Score for Risk Assessment of Emergency Department Patients With Sepsis.

OBJECTIVES: Sepsis-3 recommends using the quick Sequential Organ Failure Assessment (qSOFA) score followed by SOFA score for sepsis evaluation. The SOFA is complex and unfamiliar to most emergency physicians, while qSOFA is insensitive for sepsis screening and may result in missed cases of sepsis. The objective of this study was to devise an easy-to-use simple SOFA score for use in the emergency department (ED). METHODS: Retrospective study of ED patients with sepsis with in-hospital mortality as the primary outcome. A simple SOFA score was derived and validated and compared with SOFA and qSOFA. RESULTS: A total of 3297 patients with sepsis were included, and in-hospital mortality was 10.1%. Simple SOFA had a sensitivity and specificity of 88% and 44% in the derivation set and 93% and 44% in the validation set for in-hospital mortality, respectively. The sensitivity and specificity of qSOFA was 38% and 86% and for SOFA was 90% and 50%, respectively. There were 2760 (84%) of 3297 qSOFA-negative (<2) patients. In this group, simple SOFA had a sensitivity and specificity of 86% and 48% in the derivation set and 91% and 48% in the validation set, respectively. Sequential Organ Failure Assessment was 86% sensitive and 57% specific in qSOFA-negative patients. For all encounters, the areas under the receiver-operator characteristic curves (AUROC) were 0.82 for SOFA, 0.78 (derivation) and 0.82 (validation) for simple SOFA, and 0.68 for qSOFA. In qSOFA-negative patients, the AUROCs were 0.80 for SOFA and 0.76 (derivation) and 0.82 (validation) for simple SOFA. CONCLUSIONS: Simple SOFA demonstrates similar predictive ability for in-hospital mortality from sepsis compared to SOFA. External validation of these findings is indicated.

Sequential Organ Failure Assessment Component Score Prediction of In-hospital Mortality From Sepsis.

OBJECTIVES: Early organ dysfunction in sepsis confers a high risk of in-hospital mortality, but the relative contribution of specific types of organ failure to overall mortality is unclear. The objective of this study was to assess the predictive ability of individual types of organ failure to in-hospital mortality or prolonged intensive care. METHODS: Retrospective cohort study of adult emergency department patients with sepsis from October 1, 2013, to November 10, 2015. Multivariable regression was used to assess the odds ratios of individual organ failure types for the outcomes of in-hospital death (primary) and in-hospital death or ICU stay ≥ 3 days (secondary). RESULTS: Of 2796 patients, 283 (10%) experienced in-hospital mortality, and 748 (27%) experienced in-hospital mortality or an ICU stay ≥ 3 days. The following components of Sequential Organ Failure Assessment (SOFA) score were most predictive of in-hospital mortality (descending order): coagulation (odds ratio [OR]: 1.60, 95% confidence interval [CI]: 1.32-1.93), hepatic (1.58, 95% CI: 1.32-1.90), respiratory (OR: 1.33, 95% CI: 1.21-1.47), neurologic (OR: 1.20, 95% CI: 1.07-1.35), renal (OR: 1.14, 95% CI: 1.02-1.27), and cardiovascular (OR: 1.13, 95% CI: 1.01-1.25). For mortality or ICU stay ≥3 days, the most predictive SOFA components were respiratory (OR: 1.97, 95% CI: 1.79-2.16), neurologic (OR: 1.72, 95% CI: 1.54-1.92), cardiovascular (OR: 1.38, 95% CI: 1.23-1.54), coagulation (OR: 1.31, 95% CI: 1.10-1.55), and renal (OR: 1.19, 95% CI: 1.08-1.30) while hepatic SOFA (OR: 1.16, 95% CI: 0.98-1.37) did not reach statistical significance (P = .092). CONCLUSION: In this retrospective study, SOFA score components demonstrated varying predictive abilities for mortality in sepsis. Elevated coagulation or hepatic SOFA scores were most predictive of in-hospital death, while an elevated respiratory SOFA was most predictive of death or ICU stay >3 days.

Cholesterol levels and long-term rates of community-acquired sepsis.

BACKGROUND: Dyslipidemia is a risk factor for cardiovascular disease, with elevated low-density lipoprotein cholesterol (LDL-C) and decreased high-density lipoprotein cholesterol (HDL-C) recognized as risk factors for acute coronary events. Studies suggest an association between low cholesterol levels and poor outcomes in acute sepsis. We sought to determine the relationship between baseline cholesterol levels and long-term rates of sepsis. METHODS: We used data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort, a population-based cohort of 30,239 community-dwelling adults. The primary outcome was first sepsis event, defined as hospitalization for an infection with the presence of ≥2 systemic inflammatory response syndrome criteria (abnormal temperature, heart rate, respiratory rate, white blood cell count) during the first 28 hours of hospitalization. Cox models assessed the association between quartiles of HDL-C or LDL-C and first sepsis event, adjusted for participant demographics, health behaviors, chronic medical conditions, and biomarkers. RESULTS: We included 29,690 subjects with available baseline HDL-C and LDL-C. There were 3423 hospitalizations for serious infections, with 1845 total sepsis events among 1526 individuals. Serum HDL-C quartile was not associated with long-term rates of sepsis (hazard ratio (HR) (95% CI): Q1 (HDL-C 5-40 mg/dl), 1.08 (0.91-1.28); Q2 (HDL-C 41-49 mg/dl), 1.06 (0.90-1.26); Q3 (HDL-C 50-61 mg/dl), 1.04 (0.89-1.23); Q4, reference). However, compared with the highest quartile of LDL-C, low LDL-C was associated with higher rates of sepsis (Q1 (LDL-C 3-89 mg/dl), 1.30 (1.10-1.52); Q2 (LDL-C 90-111 mg/dl), 1.24 (1.06-1.47); Q3 (LDL-C 112-135 mg/dl), 1.07 (0.91-1.26); Q4, reference). CONCLUSION: Low LDL-C was associated with higher long-terms rates of community-acquired sepsis. HDL-C level was not associated with long-term sepsis rates.

End-tidal carbon dioxide and occult injury in trauma patients: ETCO2 does not rule out severe injury.

OBJECTIVE: To determine if early measurement of end-tidal carbon dioxide (ETCO2) in nonintubated patients triaged to a level 1 trauma center has utility in ruling out severe injury. METHODS: We performed a prospective cohort study of adult patients triaged to our urban, academic, level 1 trauma center. Included patients had ETCO2 measured within 30 minutes of arrival. Chart review was performed on enrolled patients to identify severe injury defined by: admission to an intensive care unit, need for an invasive procedure, blood product transfusion, acute blood loss anemia, and acute clinically significant finding on computed tomographic scan. RESULTS: Of 170 patients enrolled, 115 met the outcome of no severe injury. Mean ETCO2 for patients without and with severe injury was 33.1 mm Hg (SD, 5.8) and 30.3 mm Hg (SD, 6.7), respectively. This difference reached statistical significance (P=.05), but did not demonstrate added clinical utility when combined with Glasgow Coma Scale, systolic blood pressure, and age in predicting the primary outcome (area under curve, 0.70 with ETCO2 vs area under curve, 0.68 without ETCO2, P=.5). Patients with ETCO2 ≤30 mm Hg were found to be older, more likely to require intensive care unit admission or emergency operative intervention, develop acute blood loss anemia, and have an acute finding on computed tomography than patients with a higher ETCO2. CONCLUSION: End-tidal carbon dioxide cannot be used to rule out severe injury in patients meeting criteria for trauma center care. The ETCO2 ≤30 mm Hg may be associated with increased risk of traumatic severe injury.

Ultrasound-Guided Peripheral Intravenous Catheter Training Results in Physician-Level Success for Emergency Department Technicians.

OBJECTIVES: To report our success and complication rates with emergency department (ED) technician-performed ultrasound (US)-guided peripheral intravenous (IV) catheter placement and to compare our results to similar studies in the literature. METHODS: We conducted a retrospective review of a prospective database of patients who underwent US-guided peripheral IV catheter placement attempts for clinical care in the ED. All patients meeting difficult IV access criteria who had a US-guided peripheral IV catheter placement attempted by a trained ED technician were included. Average attempts per success and overall success rates were compared to similar published studies. RESULTS: There were 830 participants, with an overall success rate of ED technician- performed US-guided peripheral IV catheter placement of 97.5%. Clinicians categorized 82.6% of participants as having difficult IV access and reported that in 46.5%, a central venous catheter would have been necessary if the US-guided peripheral IV catheter failed. Of successful catheter attempts, 86.8% were placed on the first attempt; 11.6% were placed on the second attempt; and 1.6% were placed on the third attempt. For this study, the average number of attempts per success was 1.15 (95% confidence interval, 1.12-1.18), which was lower than in 6 other published studies, ranging from 1.27 to 1.70. The overall success rate of our ED technician-performed attempts was 0.970 (95% confidence interval, 0.956-0.983), which was higher than that reported in previous ED technician studies (0.79-0.80), and closer to that reported for physicians or nurses (0.87-0.97). The arterial puncture complication rate was 0.8%, which was also lower than in other published studies (1.25%-9.80%). CONCLUSIONS: With brief but comprehensive training, ED technicians can successfully obtain US-guided peripheral IV catheter access in patients with difficult IV access.

The bubble study: ultrasound confirmation of central venous catheter placement.

STUDY OBJECTIVE: The objective was to determine if ultrasound (US) can more rapidly confirm central venous catheter (CVC) position in comparison to chest radiography (CXR) in the emergency department. METHODS: The study included a convenience sample of emergency department patients with supradiaphragmatic CVCs and a CXR for confirmation. Ultrasound was used for CVC confirmation by visualizing microbubble artifact in the right atrium after injection of saline through the distal port. To evaluate for pneumothorax (PTX), "sliding sign" of the pleura was noted on US of the anterior chest. Blinded chart review was performed to assess CXR timing, catheter position and CVC complications. Student's t test was used to compare US time to CXR performance time and radiologist reading time. RESULTS: Fifty patients were enrolled; 4 were excluded because of inadequate views. Forty-six patients were included in the final analysis. Mean total US time was 5.0 minutes (95% confidence interval [CI], 4.2-5.9) compared to 28.2 minutes (95% CI, 16.8-39.4) for CXR performance with a mean difference of 23.1 minutes (95% CI, -34.5 to -11.8; P < .0002). When comparing only US CVC confirmation time to CXR time, US was an average of 24.0 minutes (95% CI, -35.4 to -12.7; P < .0001) faster. Comparing total US time to radiologist CXR reading time, US was an average of 294 minutes faster (95% CI, -384.5 to -203.5; P < .0000). There were a total of 3 misplaced lines and 2 patients with PTX, all of which were identified correctly on US. CONCLUSION: Ultrasound can confirm CVC placement and rule out PTX significantly faster than CXR, expediting the use of CVCs in the critically ill.

The relationship of intravenous fluid chloride content to kidney function in patients with severe sepsis or septic shock.

BACKGROUND: Previous studies suggest a relationship between chloride-rich intravenous fluids and acute kidney injury in critically ill patients. OBJECTIVES: The aim of this study was to evaluate the relationship of intravenous fluid chloride content to kidney function in patients with severe sepsis or septic shock. METHODS: A retrospective chart review was performed to determine (1) quantity and type of bolus intravenous fluids, (2) serum creatinine (Cr) at presentation and upon discharge, and (3) need for emergent hemodialysis (HD) or renal replacement therapy (RRT). Linear regression was used for continuous outcomes, and logistic regression was used for binary outcomes and results were controlled for initial Cr. The primary outcome was change in Cr from admission to discharge. Secondary outcomes were need for HD/RRT, length of stay (LOS), mortality, and organ dysfunction. RESULTS: There were 95 patients included in the final analysis; 48% (46) of patients presented with acute kidney injury, 8% (8) required first-time HD or RRT, 61% (58) were culture positive, 55% (52) were in shock, and overall mortality was 20% (19). There was no significant relationship between quantity of chloride administered in the first 24 hours with change in Cr (ß = -0.0001, t = -0.86, R(2) = 0.92, P = .39), need for HD or RRT (odds ratio [OR] = 0.999; 95% confidence interval [CI], 0.999-1.000; P = .77), LOS >14 days (OR = 1.000; 95% CI, 0.999-1.000; P = .68), mortality (OR = 0.999; 95% CI, 0.999-1.000; P = .88), or any type of organ dysfunction. CONCLUSION: Chloride administered in the first 24 hours did not influence kidney function in this cohort with severe sepsis or septic shock.

End-tidal carbon dioxide as a goal of early sepsis therapy.

OBJECTIVE: To determine the use of end-tidal carbon dioxide (etco2) as an end point of sepsis resuscitation. METHODS: This was a prospective, observational, single-center cohort study of emergency department patients receiving treatment for severe sepsis with a quantitative resuscitation protocol. Three etco2 readings were taken during a 1-minute time frame at 0, 3, and 6 hours of treatment. Linear regression was used to characterize the association between etco2 and central venous oxygen saturation (SCVo2) and lactate and also to determine the relationship between their change. Analysis of variance was used to determine the relationship between etco2 and disposition. RESULTS: Sixty-nine patients were included in our final analysis. For baseline values, linear regression failed to show a relationship between etco2 and SCVo2 (ß = -0.04, t(70) = -0.53, P = .60) but showed a nearly significant relationship (ß = -0.51, t(70) = -1.90, P = .06) with lactate. There was no significant relationship between etco2 and SCVo2 at 3 hours (ß = 0.12, t(70) = 1.43, P = .16) or 6 hours (ß = 0.05, t(64) = 0.82, P = .67). There was also no significant relationship between 6-hour change in etco2 and change in SCVo2 (ß = 0.04, t(64) = 0.43, P = .67) or lactate (ß = 0.04, t(59) = 0.52, P = .60) or disposition (F(4) = 0.78, P = .54). CONCLUSION: End-tidal carbon dioxide is unlikely to be a useful clinical end point for sepsis resuscitation, although it may be useful as a triage tool in suspected sepsis because baseline values may reflect initial lactate.

Lipidomic changes in a novel sepsis outcome-based analysis reveals potent pro-inflammatory and pro-resolving signaling lipids.

The purpose of this study was to investigate changes in the lipidome of patients with sepsis to identify signaling lipids associated with poor outcomes that could be linked to future therapies. Adult patients with sepsis were enrolled within 24h of sepsis recognition. Patients meeting Sepsis-3 criteria were enrolled from the emergency department or intensive care unit and blood samples were obtained. Clinical data were collected and outcomes of rapid recovery, chronic critical illness (CCI), or early death were adjudicated by clinicians. Lipidomic analysis was performed on two platforms, the Sciex™ 5500 device to perform a lipidomic screen of 1450 lipid species and a targeted signaling lipid panel using liquid-chromatography tandem mass spectrometry. For the lipidomic screen, there were 274 patients with sepsis: 192 with rapid recovery, 47 with CCI, and 35 with early deaths. CCI and early death patients were grouped together for analysis. Fatty acid (FA) 12:0 was decreased in CCI/early death, whereas FA 17:0 and 20:1 were elevated in CCI/early death, compared to rapid recovery patients. For the signaling lipid panel analysis, there were 262 patients with sepsis: 189 with rapid recovery, 45 with CCI, and 28 with early death. Pro-inflammatory signaling lipids from ω-6 poly-unsaturated fatty acids (PUFAs), including 15-hydroxyeicosatetraenoic (HETE), 12-HETE, and 11-HETE (oxidation products of arachidonic acid [AA]) were elevated in CCI/early death patients compared to rapid recovery. The pro-resolving lipid mediator from ω-3 PUFAs, 14(S)-hydroxy docosahexaenoic acid (14S-HDHA), was also elevated in CCI/early death compared to rapid recovery. Signaling lipids of the AA pathway were elevated in poor-outcome patients with sepsis and may serve as targets for future therapies.

TRENDS IN CHOLESTEROL AND LIPOPROTEINS ARE ASSOCIATED WITH ACUTE RESPIRATORY DISTRESS SYNDROME INCIDENCE AND DEATH AMONG SEPSIS PATIENTS.

ABSTRACT: Objective: Compare changes in cholesterol and lipoprotein levels occurring in septic patients with and without acute respiratory distress syndrome (ARDS) and by survivorship. Methods: We reanalyzed data from prospective sepsis studies. Cholesterol and lipoprotein levels were analyzed using univariate testing to detect changes between septic patients with or without ARDS, and among ARDS survivors compared with nonsurvivors at enrollment (first 24 h of sepsis) and 48 to 72 h later. Results: 214 patients with sepsis were included of whom 48 had ARDS and 166 did not have ARDS. Cholesterol and lipoproteins among septic ARDS versus non-ARDS showed similar enrollment levels. However, 48 to 72 h after enrollment, change in median total cholesterol (48/72 h - enrollment) was significantly different between septic ARDS (-4, interquartile range [IQR] -23.5, 6.5, n = 35) and non-ARDS (0, -10.0, 17.5, P = 0.04; n = 106). When compared by ARDS survivorship, ARDS nonsurvivors (n = 14) had lower median total cholesterol levels (75.5, IQR 68.4, 93.5) compared with ARDS survivors (113.0, IQR 84.0, 126.8, P = 0.022), and lower median enrollment low-density lipoprotein cholesterol (LDL-C) levels (27, IQR 19.5-34.5) compared with ARDS survivors (43, IQR 27-67, P = 0.013; n = 33). Apolipoprotein A-I levels were also significantly lower in ARDS nonsurvivors (n = 14) (87.6, IQR 76.45-103.64) compared with ARDS survivors (130.0, IQR 73.25-165.47, P = 0.047; n = 33). At 48 to 72 h, for ARDS nonsurvivors, median levels of low-density lipoprotein cholesterol (9.0, IQR 4.3, 18.0; n = 10), LDL-C (17.0, IQR 5.0, 29.0; n = 9), and total cholesterol (59.0, 45.3, 81.5; n = 10) were significantly lower compared with ARDS survivors' (n = 25) levels of low-density lipoprotein cholesterol (20.0, IQR 12.0-39.0, P = 0.014), LDL-C (42.0, IQR 27.0-58.0, P = 0.019), and total cholesterol (105.0, IQR 91.0, 115.0, P = 0.003). Conclusions: Change in total cholesterol was different in septic ARDS versus non-ARDS. Total cholesterol, LDL-C, and apolipoprotein A-I levels were lower in ARDS nonsurvivors compared with survivors. Future studies of dysregulated cholesterol metabolism in septic ARDS patients are needed to understand biology and links to potential therapies.

Racial disparities in septic shock mortality: a retrospective cohort study.

Background: Patients with septic shock have the highest risk of death from sepsis, however, racial disparities in mortality outcomes in this cohort have not been rigorously investigated. Our objective was to describe the association between race/ethnicity and mortality in patients with septic shock. Methods: Our study is a retrospective cohort study of adult patients in the OneFlorida Data Trust (Florida, United States of America) admitted with septic shock between January 2012 and July 2018. We identified patients as having septic shock if they received vasopressors during their hospital encounter and had either an explicit International Classification of Disease (ICD) code for sepsis, or had an infection ICD code and received intravenous antibiotics. Our primary outcome was 90-day mortality. Our secondary outcome was in-hospital mortality. Multiple logistic regression with Least Absolute Shrinkage and Selection Operator (LASSO) for variable selection was used to assess associations. Findings: There were 13,932 patients with septic shock in our cohort. The mean age was 61 years (SD 16), 68% of the cohort identified as White (n = 9419), 28% identified as Black (n = 3936), 2% (n = 294) identified as Hispanic ethnicity, and 2% as other races not specified in the previous groups (n = 283). In our logistic regression model for 90-day mortality, patients identified as Black had 1.57 times the odds of mortality (95% CI 1.07-2.29, p = 0.02) compared to White patients. Other significant predictors included mechanical ventilation (OR 3.66, 95% CI 3.35-4.00, p < 0.01), liver disease (OR 1.75, 95% CI 1.59-1.93, p < 0.01), laboratory components of the Sequential Organ Failure Assessment score (OR 1.18, 95% CI 1.16-1.21, p < 0.01), lactate (OR 1.10, 95% CI 1.08-1.12, p < 0.01), congestive heart failure (OR 1.19, 95% CI 1.10-1.30, p < 0.01), human immunodeficiency virus (OR 1.35, 95% CI 1.04-1.75, p = 0.03), age (OR 1.04, 95% CI 1.04-1.04, p < 0.01), and the interaction between age and race (OR 0.99, 95% CI 0.99-1.00, p < 0.01). Among younger patients (<45 years), patients identified as Black accounted for a higher proportion of the deaths. Results were similar in the in-hospital mortality model. Interpretation: In this retrospective study of septic shock patients, we found that patients identified as Black had higher odds of mortality compared to patients identified as non-Hispanic White. Our findings suggest that the greatest disparities in mortality are among younger Black patients with septic shock. Funding: National Institutes of Health National Center for Advancing Translational Sciences (1KL2TR001429); National Institute of Health National Institute of General Medical Sciences (1K23GM144802).

Association Between Hypocholesterolemia and Mortality in Critically Ill Patients With Sepsis: A Systematic Review and Meta-Analysis.

To ascertain the association between cholesterol and triglyceride levels on ICU admission and mortality in patients with sepsis. DATA SOURCES: Systematic review and meta-analysis of published studies on PubMed and Embase. STUDY SELECTION: All observational studies reporting ICU admission cholesterol and triglyceride levels in critically ill patients with sepsis were included. Authors were contacted for further data. DATA EXTRACTION: Eighteen observational studies were identified, including 1,283 patients with a crude overall mortality of 33.3%. Data were assessed using Revman (Version 5.1, Cochrane Collaboration, Oxford, United Kingdom) and presented as mean difference (MD) with 95% CIs, p values, and I 2 values. DATA SYNTHESIS: Admission levels of total cholesterol (17 studies, 1,204 patients; MD = 0.52 mmol/L [0.27-0.77 mmol/L]; p < 0.001; I 2 = 91%), high-density lipoprotein (HDL)-cholesterol (14 studies, 991 patients; MD = 0.08 mmol/L [0.01-0.15 mmol/L]; p = 0.02; I 2 = 61%), and low-density lipoprotein (LDL)-cholesterol (15 studies, 1,017 patients; MD = 0.18 mmol/L [0.04-0.32 mmol/L]; p = 0.01; I 2 = 71%) were significantly lower in eventual nonsurvivors compared with survivors. No association was seen between admission triglyceride levels and mortality (15 studies, 1,070 patients; MD = 0.00 mmol/L [-0.16 to 0.15 mmol/L]; p = -0.95; I 2 = 79%). CONCLUSIONS: Mortality was associated with lower levels of total cholesterol, HDL-cholesterol, and LDL-cholesterol, but not triglyceride levels, in patients admitted to ICU with sepsis. The impact of cholesterol replacement on patient outcomes in sepsis, particularly in at-risk groups, merits investigation.

DHCR7 Expression Predicts Poor Outcomes and Mortality from Sepsis.

Objective: Sepsis patients experience poor outcomes including chronic critical illness (CCI) or early death (within 14 days). We investigated lipid metabolic gene expression differences by outcome to discover therapeutic targets. Design: Secondary analysis of samples from prospectively enrolled sepsis patients and a zebrafish sepsis model for drug discovery. Setting: Emergency department or ICU at an urban teaching hospital. Patients: Sepsis patients presenting within 24 hours. Methods: Enrollment samples from sepsis patients were analyzed. Clinical data and cholesterol levels were recorded. Leukocytes were processed for RNA sequencing (RNA-seq) and reverse transcriptase polymerase chain reaction (RT-qPCR). A lipopolysaccharide (LPS) zebrafish sepsis model was used for confirmation of human transcriptomic findings and drug discovery. Measurements and Main Results: There were 96 samples in the derivation (76 sepsis, 20 controls) and 52 in the validation cohort (sepsis only). The cholesterol metabolism gene 7-Dehydrocholesterol Reductase ( DHCR7) was significantly upregulated in both derivation and validation cohorts in poor outcome sepsis compared to rapid recovery patients and in 90-day non-survivors (validation only) and validated using RT-qPCR analysis. Our zebrafish sepsis model showed upregulation of dhcr7 and several of the same lipid genes upregulated in poor outcome human sepsis (dhcr24, sqlea, cyp51, msmo1 , ldlra) compared to controls. We then tested six lipid-based drugs in the zebrafish sepsis model. Of these, only the Dhcr7 inhibitor AY9944 completely rescued zebrafish from LPS death in a model with 100% lethality. Conclusions: DHCR7, an important cholesterol metabolism gene, was upregulated in poor outcome sepsis patients warranting external validation. This pathway may serve as a potential therapeutic target to improve sepsis outcomes.

DHCR7 Expression Predicts Poor Outcomes and Mortality From Sepsis.

This is a study of lipid metabolic gene expression patterns to discover precision medicine for sepsis. OBJECTIVES: Sepsis patients experience poor outcomes including chronic critical illness (CCI) or early death (within 14 d). We investigated lipid metabolic gene expression differences by outcome to discover therapeutic targets. DESIGN SETTING AND PARTICITPANTS: Secondary analysis of samples from prospectively enrolled sepsis patients (first 24 hr) and a zebrafish endotoxemia model for drug discovery. Patients were enrolled from the emergency department or ICU at an urban teaching hospital. Enrollment samples from sepsis patients were analyzed. Clinical data and cholesterol levels were recorded. Leukocytes were processed for RNA sequencing and reverse transcriptase polymerase chain reaction. A lipopolysaccharide zebrafish endotoxemia model was used for confirmation of human transcriptomic findings and drug discovery. MAIN OUTCOMES AND MEASURES: The derivation cohort included 96 patients and controls (12 early death, 13 CCI, 51 rapid recovery, and 20 controls) and the validation cohort had 52 patients (6 early death, 8 CCI, and 38 rapid recovery). RESULTS: The cholesterol metabolism gene 7-dehydrocholesterol reductase (DHCR7) was significantly up-regulated in both derivation and validation cohorts in poor outcome sepsis compared with rapid recovery patients and in 90-day nonsurvivors (validation only) and validated using RT-qPCR analysis. Our zebrafish sepsis model showed up-regulation of dhcr7 and several of the same lipid genes up-regulated in poor outcome human sepsis (dhcr24, sqlea, cyp51, msmo1, and ldlra) compared with controls. We then tested six lipid-based drugs in the zebrafish endotoxemia model. Of these, only the Dhcr7 inhibitor AY9944 completely rescued zebrafish from lipopolysaccharide death in a model with 100% lethality. CONCLUSIONS: DHCR7, an important cholesterol metabolism gene, was up-regulated in poor outcome sepsis patients warranting external validation. This pathway may serve as a potential therapeutic target to improve sepsis outcomes.

Efficacy of Losartan in Hospitalized Patients With COVID-19-Induced Lung Injury: A Randomized Clinical Trial.

Importance: SARS-CoV-2 viral entry may disrupt angiotensin II (AII) homeostasis, contributing to COVID-19 induced lung injury. AII type 1 receptor blockade mitigates lung injury in preclinical models, although data in humans with COVID-19 remain mixed. Objective: To test the efficacy of losartan to reduce lung injury in hospitalized patients with COVID-19. Design, Setting, and Participants: This blinded, placebo-controlled randomized clinical trial was conducted in 13 hospitals in the United States from April 2020 to February 2021. Hospitalized patients with COVID-19 and a respiratory sequential organ failure assessment score of at least 1 and not already using a renin-angiotensin-aldosterone system (RAAS) inhibitor were eligible for participation. Data were analyzed from April 19 to August 24, 2021. Interventions: Losartan 50 mg orally twice daily vs equivalent placebo for 10 days or until hospital discharge. Main Outcomes and Measures: The primary outcome was the imputed arterial partial pressure of oxygen to fraction of inspired oxygen (Pao2:Fio2) ratio at 7 days. Secondary outcomes included ordinal COVID-19 severity; days without supplemental o2, ventilation, or vasopressors; and mortality. Losartan pharmacokinetics and RAAS components (AII, angiotensin-[1-7] and angiotensin-converting enzymes 1 and 2)] were measured in a subgroup of participants. Results: A total of 205 participants (mean [SD] age, 55.2 [15.7] years; 123 [60.0%] men) were randomized, with 101 participants assigned to losartan and 104 participants assigned to placebo. Compared with placebo, losartan did not significantly affect Pao2:Fio2 ratio at 7 days (difference, -24.8 [95%, -55.6 to 6.1]; P = .12). Compared with placebo, losartan did not improve any secondary clinical outcomes and led to fewer vasopressor-free days than placebo (median [IQR], 9.4 [9.1-9.8] vasopressor-free days vs 8.7 [8.2-9.3] vasopressor-free days). Conclusions and Relevance: This randomized clinical trial found that initiation of orally administered losartan to hospitalized patients with COVID-19 and acute lung injury did not improve Pao2:Fio2 ratio at 7 days. These data may have implications for ongoing clinical trials. Trial Registration: ClinicalTrials.gov Identifier: NCT04312009.

Lipid and Lipoprotein Dysregulation in Sepsis: Clinical and Mechanistic Insights into Chronic Critical Illness.

In addition to their well-characterized roles in metabolism, lipids and lipoproteins have pleiotropic effects on the innate immune system. These undergo clinically relevant alterations during sepsis and acute inflammatory responses. High-density lipoprotein (HDL) plays an important role in regulating the immune response by clearing bacterial toxins, supporting corticosteroid release, decreasing platelet aggregation, inhibiting endothelial cell apoptosis, reducing the monocyte inflammatory response, and inhibiting expression of endothelial cell adhesion molecules. It undergoes quantitative as well as qualitative changes which can be measured using the HDL inflammatory index (HII). Pro-inflammatory, or dysfunctional HDL (dysHDL) lacks the ability to perform these functions, and we have also found it to independently predict adverse outcomes and organ failure in sepsis. Another important class of lipids known as specialized pro-resolving mediators (SPMs) positively affect the escalation and resolution of inflammation in a temporal fashion. These undergo phenotypic changes in sepsis and differ significantly between survivors and non-survivors. Certain subsets of sepsis survivors go on to have perilous post-hospitalization courses where this inflammation continues in a low grade fashion. This is associated with immunosuppression in a syndrome of persistent inflammation, immunosuppression, and catabolism syndrome (PICS). The continuous release of tissue damage-related patterns and viral reactivation secondary to immunosuppression feed this chronic cycle of inflammation. Animal data indicate that dysregulation of endogenous lipids and SPMs play important roles in this process. Lipids and their associated pathways have been the target of many clinical trials in recent years which have not shown mortality benefit. These results are limited by patient heterogeneity and poor animal models. Considerations of sepsis phenotypes and novel biomarkers in future trials are important factors to be considered in future research. Further characterization of lipid dysregulation and chronic inflammation during sepsis will aid mortality risk stratification, detection of sepsis, and inform individualized pharmacologic therapies.