Angiotensin II enhances bacterial clearance via myeloid signaling in a murine sepsis model.

Sepsis, defined as organ dysfunction caused by a dysregulated host-response to infection, is characterized by immunosuppression. The vasopressor norepinephrine is widely used to treat low blood pressure in sepsis but exacerbates immunosuppression. An alternative vasopressor is angiotensin-II, a peptide hormone of the renin-angiotensin system (RAS), which displays complex immunomodulatory properties that remain unexplored in severe infection. In a murine cecal ligation and puncture (CLP) model of sepsis, we found alterations in the surface levels of RAS proteins on innate leukocytes in peritoneum and spleen. Angiotensin-II treatment induced biphasic, angiotensin-II type 1 receptor (AT1R)-dependent modulation of the systemic inflammatory response and decreased bacterial counts in both the blood and peritoneal compartments, which did not occur with norepinephrine treatment. The effect of angiotensin-II was preserved when treatment was delivered remote from the primary site of infection. At an independent laboratory, angiotensin-II treatment was compared in LysM-Cre AT1aR-/- (Myeloid-AT1a-) mice, which selectively do not express AT1R on myeloid-derived leukocytes, and littermate controls (Myeloid-AT1a+). Angiotensin-II treatment significantly reduced post-CLP bacteremia in Myeloid-AT1a+ mice but not in Myeloid-AT1a- mice, indicating that the AT1R-dependent effect of angiotensin-II on bacterial clearance was mediated through myeloid-lineage cells. Ex vivo, angiotensin-II increased post-CLP monocyte phagocytosis and ROS production after lipopolysaccharide stimulation. These data identify a mechanism by which angiotensin-II enhances the myeloid innate immune response during severe systemic infection and highlight a potential role for angiotensin-II to augment immune responses in sepsis.

M1 cholinergic signaling in the brain modulates cytokine levels and splenic cell sub-phenotypes following cecal ligation and puncture.

BACKGROUND: The contribution of the central nervous system to sepsis pathobiology is incompletely understood. In previous studies, administration of endotoxin to mice decreased activity of the vagus anti-inflammatory reflex. Treatment with the centrally-acting M1 muscarinic acetylcholine (ACh) receptor (M1AChR) attenuated this endotoxin-mediated change. We hypothesize that decreased M1AChR-mediated activity contributes to inflammation following cecal ligation and puncture (CLP), a mouse model of sepsis. METHODS: In male C57Bl/6 mice, we quantified basal forebrain cholinergic activity (immunostaining), hippocampal neuronal activity, serum cytokine/chemokine levels (ELISA) and splenic cell subtypes (flow cytometry) at baseline, following CLP and following CLP in mice also treated with the M1AChR agonist xanomeline. RESULTS: At 48 h. post-CLP, activity in basal forebrain cells expressing choline acetyltransferase (ChAT) was half of that observed at baseline. Lower activity was also noted in the hippocampus, which contains projections from ChAT-expressing basal forebrain neurons. Serum levels of TNFα, IL-1ß, MIP-1α, IL-6, KC and G-CSF were higher post-CLP than at baseline. Post-CLP numbers of splenic macrophages and inflammatory monocytes, TNFα+ and ILß+ neutrophils and ILß+ monocytes were higher than baseline while numbers of central Dendritic Cells (cDCs), CD4+ and CD8+ T cells were lower. When, following CLP, mice were treated with xanomeline activity in basal forebrain ChAT-expressing neurons and in the hippocampus was significantly higher than in untreated animals. Post-CLP serum concentrations of TNFα, IL-1ß, and MIP-1α, but not of IL-6, KC and G-CSF, were significantly lower in xanomeline-treated mice than in untreated mice. Post-CLP numbers of splenic neutrophils, macrophages, inflammatory monocytes and TNFα+ neutrophils also were lower in xanomeline-treated mice than in untreated animals. Percentages of IL-1ß+ neutrophils, IL-1ß+ monocytes, cDCs, CD4+ T cells and CD8+ T cells were similar in xanomeline-treated and untreated post-CLP mice. CONCLUSION: Our findings indicate that M1AChR-mediated responses modulate CLP-induced alterations in serum levels of some, but not all, cytokines/chemokines and affected splenic immune response phenotypes.

Effect of Automated Real-Time Feedback on Early-Sepsis Care: A Pragmatic Clinical Trial.

OBJECTIVES: To determine if a real-time monitoring system with automated clinician alerts improves 3-hour sepsis bundle adherence. DESIGN: Prospective, pragmatic clinical trial. Allocation alternated every 7 days. SETTING: Quaternary hospital from December 1, 2020 to November 30, 2021. PATIENTS: Adult emergency department or inpatients meeting objective sepsis criteria triggered an electronic medical record (EMR)-embedded best practice advisory. Enrollment occurred when clinicians acknowledged the advisory indicating they felt sepsis was likely. INTERVENTION: Real-time automated EMR monitoring identified suspected sepsis patients with incomplete bundle measures within 1-hour of completion deadlines and generated reminder pages. Clinicians responsible for intervention group patients received reminder pages; no pages were sent for controls. The primary analysis cohort was the subset of enrolled patients at risk of bundle nonadherent care that had reminder pages generated. MEASUREMENTS AND MAIN RESULTS: The primary outcome was orders for all 3-hour bundle elements within guideline time limits. Secondary outcomes included guideline-adherent delivery of all 3-hour bundle elements, 28-day mortality, antibiotic discontinuation within 48-hours, and pathogen recovery from any culture within 7 days of time-zero. Among 3,269 enrolled patients, 1,377 had reminder pages generated and were included in the primary analysis. There were 670 (48.7%) at-risk patients randomized to paging alerts and 707 (51.3%) to control. Bundle-adherent orders were placed for 198 intervention patients (29.6%) versus 149 (21.1%) controls (difference: 8.5%; 95% CI, 3.9-13.1%; p = 0.0003). Bundle-adherent care was delivered for 152 (22.7%) intervention versus 121 (17.1%) control patients (difference: 5.6%; 95% CI, 1.4-9.8%; p = 0.0095). Mortality was similar between groups (8.4% vs 8.3%), as were early antibiotic discontinuation (35.1% vs 33.4%) and pan-culture negativity (69.0% vs 68.2%). CONCLUSIONS: Real-time monitoring and paging alerts significantly increased orders for and delivery of guideline-adherent care for suspected sepsis patients at risk of 3-hour bundle nonadherence. The trial was underpowered to determine whether adherence affected mortality. Despite enrolling patients with clinically suspected sepsis, early antibiotic discontinuation and pan-culture negativity were common, highlighting challenges in identifying appropriate patients for sepsis bundle application.

ACE inhibitors and angiotensin receptor blockers differentially alter the response to angiotensin II treatment in vasodilatory shock.

BACKGROUND: Angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blockers (ARB) medications are widely prescribed. We sought to assess how pre-admission use of these medications might impact the response to angiotensin-II treatment during vasodilatory shock. METHODS: In a post-hoc subgroup analysis of the randomized, placebo-controlled, Angiotensin Therapy for High Output Shock (ATHOS-3) trial, we compared patients with chronic angiotensin-converting enzyme inhibitor (ACEi) use, and patients with angiotensin receptor blocker (ARB) use, to patients without exposure to either ACEi or ARB. The primary outcome was mean arterial pressure after 1-h of treatment. Additional clinical outcomes included mean arterial pressure and norepinephrine equivalent dose requirements over time, and study-drug dose over time. Biological outcomes included baseline RAS biomarkers (renin, angiotensin-I, angiotensin-II, and angiotensin-I/angiotensin-II ratio), and the change in renin from 0 to 3 h. RESULTS: We included n = 321 patients, of whom, 270 were ACEi and ARB-unexposed, 29 were ACEi-exposed and 22 ARB-exposed. In ACEi/ARB-unexposed patients, angiotensin-treated patients, compared to placebo, had higher hour-1 mean arterial pressure (9.1 mmHg [95% CI 7.6-10.1], p < 0.0001), lower norepinephrine equivalent dose over 48-h (p = 0.0037), and lower study-drug dose over 48-h (p < 0.0001). ACEi-exposed patients treated with angiotensin-II showed similarly higher hour-1 mean arterial pressure compared to ACEi/ARB-unexposed (difference in treatment-effect: - 2.2 mmHg [95% CI - 7.0-2.6], pinteraction = 0.38), but a greater reduction in norepinephrine equivalent dose (pinteraction = 0.0031) and study-drug dose (pinteraction < 0.0001) over 48-h. In contrast, ARB-exposed patients showed an attenuated effect of angiotensin-II on hour-1 mean arterial pressure versus ACEi/ARB-unexposed (difference in treatment-effect: - 6.0 mmHg [95% CI - 11.5 to - 0.6], pinteraction = 0.0299), norepinephrine equivalent dose (pinteraction < 0.0001), and study-drug dose (pinteraction = 0.0008). Baseline renin levels and angiotensin-I/angiotensin-II ratios were highest in ACEi-exposed patients. Finally, angiotensin-II treatment reduced hour-3 renin in ACEi/ARB-unexposed and ACEi-exposed patients but not in ARB-exposed patients. CONCLUSIONS: In vasodilatory shock patients, the cardiovascular and biological RAS response to angiotensin-II differed based upon prior exposure to ACEi and ARB medications. ACEi-exposure was associated with increased angiotensin II responsiveness, whereas ARB-exposure was associated with decreased responsiveness. These findings have clinical implications for patient selection and dosage of angiotensin II in vasodilatory shock. Trial Registration ClinicalTrials.Gov Identifier: NCT02338843 (Registered January 14th 2015).

Alveolar, Endothelial, and Organ Injury Marker Dynamics in Severe COVID-19.

Rationale: Alveolar and endothelial injury may be differentially associated with coronavirus disease (COVID-19) severity over time. Objectives: To describe alveolar and endothelial injury dynamics and associations with COVID-19 severity, cardiorenovascular injury, and outcomes. Methods: This single-center observational study enrolled patients with COVID-19 requiring respiratory support at emergency department presentation. More than 40 markers of alveolar (including receptor for advanced glycation endproducts [RAGE]), endothelial (including angiopoietin-2), and cardiorenovascular injury (including renin, kidney injury molecule-1, and troponin-I) were serially compared between invasively and spontaneously ventilated patients using mixed-effects repeated-measures models. Ventilatory ratios were calculated for intubated patients. Associations of biomarkers with modified World Health Organization scale at Day 28 were determined with multivariable proportional-odds regression. Measurements and Main Results: Of 225 patients, 74 (33%) received invasive ventilation at Day 0. RAGE was 1.80-fold higher in invasive ventilation patients at Day 0 (95% confidence interval [CI], 1.50-2.17) versus spontaneous ventilation, but decreased over time in all patients. Changes in alveolar markers did not correlate with changes in endothelial, cardiac, or renal injury markers. In contrast, endothelial markers were similar to lower at Day 0 for invasive ventilation versus spontaneous ventilation, but then increased over time only among intubated patients. In intubated patients, angiopoietin-2 was similar (fold difference, 1.02; 95% CI, 0.89-1.17) to nonintubated patients at Day 0 but 1.80-fold higher (95% CI, 1.56-2.06) at Day 3; cardiorenovascular injury markers showed similar patterns. Endothelial markers were not consistently associated with ventilatory ratios. Endothelial markers were more often significantly associated with 28-day outcomes than alveolar markers. Conclusions: Alveolar injury markers increase early. Endothelial injury markers increase later and are associated with cardiorenovascular injury and 28-day outcome. Alveolar and endothelial injury likely contribute at different times to disease progression in severe COVID-19.

Impaired angiotensin II type 1 receptor signaling contributes to sepsis-induced acute kidney injury.

In sepsis-induced acute kidney injury, kidney blood flow may increase despite decreased glomerular filtration. Normally, angiotensin-II reduces kidney blood flow to maintain filtration. We hypothesized that sepsis reduces angiotensin type-1 receptor (AT1R) expression to account for this observation and tested this hypothesis in a patient case-control study and studies in mice. Seventy-three mice underwent cecal ligation and puncture (a sepsis model) or sham operation. Additionally, 94 septic mice received losartan (selective AT1R antagonist), angiotensin II without or with losartan, or vehicle. Cumulative urine output, kidney blood flow, blood urea nitrogen, and creatinine were measured. AT1R expression was assessed using ELISA, qPCR, and immunofluorescence. A blinded pathologist evaluated tissue for ischemic injury. AT1R expression was compared in autopsy tissue from seven patients with sepsis to that of the non-involved portion of kidney from ten individuals with kidney cancer and three non-infected but critically ill patients. By six hours post ligation/puncture, kidney blood flow doubled, blood urea nitrogen rose, and urine output fell. Concurrently, AT1R expression significantly fell 2-fold in arterioles and the macula densa. Creatinine significantly rose by 24 hours and sham operation did not alter measurements. Losartan significantly exacerbated ligation/puncture-induced changes in kidney blood flow, blood urea nitrogen, creatinine, and urine output. There was no histologic evidence of cortical ischemia. Significantly, angiotensin II prevented changes in kidney blood flow, creatinine, and urine output compared to vehicle. Co-administering losartan with angiotensin-II reversed this protection. Relative to both controls, patients with sepsis had low AT1R expression in arterioles and macula densa. Thus, murine cecal ligation/puncture and clinical sepsis decrease renal AT1R expression. Angiotensin II prevents functional changes while AT1R-blockade exacerbates them independent of ischemia in mice.

General and Intensive Care Outcomes for Hospitalized Patients With Solid Organ Transplants With COVID-19.

PURPOSE: COVID-19 has been associated with a dysregulated inflammatory response. Patients who have received solid-organ transplants are more susceptible to infections in general due to the use of immunosuppressants. We investigated factors associated with mechanical ventilation and outcomes in solid-organ transplant recipients with COVID-19. MATERIALS AND METHODS: We conducted a retrospective cohort study of all solid-organ transplant recipients admitted with a diagnosis of COVID-19 in our 23-hospital health system over a 1-month period. Descriptive statistics were used to describe hospital course and laboratory results and bivariate comparisons were performed on variables to determine differences. RESULTS: Twenty-two patients with solid-organ transplants and COVID-19 were identified. Eight patients were admitted to the ICU, of which 7 were intubated. Admission values of CRP (p = 0.045) and N/L ratio (p = 0.047) were associated with the need for mechanical ventilation. Seven patients (32%) died during admission, including 86% (n = 6) of patients who received mechanical ventilation. CONCLUSIONS: In solid-organ transplant recipients with COVID-19, initial CRP and N/L ratio were associated with need for mechanical ventilation.

Development and Reporting of Prediction Models: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals.

Prediction models aim to use available data to predict a health state or outcome that has not yet been observed. Prediction is primarily relevant to clinical practice, but is also used in research, and administration. While prediction modeling involves estimating the relationship between patient factors and outcomes, it is distinct from casual inference. Prediction modeling thus requires unique considerations for development, validation, and updating. This document represents an effort from editors at 31 respiratory, sleep, and critical care medicine journals to consolidate contemporary best practices and recommendations related to prediction study design, conduct, and reporting. Herein, we address issues commonly encountered in submissions to our various journals. Key topics include considerations for selecting predictor variables, operationalizing variables, dealing with missing data, the importance of appropriate validation, model performance measures and their interpretation, and good reporting practices. Supplemental discussion covers emerging topics such as model fairness, competing risks, pitfalls of "modifiable risk factors", measurement error, and risk for bias. This guidance is not meant to be overly prescriptive; we acknowledge that every study is different, and no set of rules will fit all cases. Additional best practices can be found in the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines, to which we refer readers for further details.

Predictors, Prevalence, and Outcomes of Early Crystalloid Responsiveness Among Initially Hypotensive Patients With Sepsis and Septic Shock.

OBJECTIVES: The prevalence of responsiveness to initial fluid challenge among hypotensive sepsis patients is unclear. To avoid fluid overload, and unnecessary treatment, it is important to differentiate these phenotypes. We aimed to 1) determine the proportion of hypotensive sepsis patients sustaining favorable hemodynamic response after initial fluid challenge, 2) determine demographic and clinical risk factors that predicted refractory hypotension, and 3) assess the association between timeliness of fluid resuscitation and refractoriness. DESIGN: Secondary analysis of a prospective, multisite, observational, consecutive-sample cohort. SETTING: Nine tertiary and community hospitals over 1.5 years. PATIENTS: Inclusion criteria 1) suspected or confirmed infection, 2) greater than or equal to two systemic inflammatory response syndrome criteria, 3) systolic blood pressure less than 90 mm Hg, greater than 40% decrease from baseline, or mean arterial pressure less than 65 mm Hg. MEASUREMENTS AND MAIN RESULTS: Sex, age, heart failure, renal failure, immunocompromise, source of infection, initial lactate, coagulopathy, temperature, altered mentation, altered gas exchange, and acute kidney injury were used to generate a risk score. The primary outcome was sustained normotension after fluid challenge without vasopressor titration. Among 3,686 patients, 2,350 (64%) were fluid responsive. Six candidate risk factors significantly predicted refractoriness in multivariable analysis: heart failure (odds ratio, 1.43; CI, 1.20-1.72), hypothermia (odds ratio, 1.37; 1.10-1.69), altered gas exchange (odds ratio, 1.33; 1.12-1.57), initial lactate greater than or equal to 4.0 mmol/L (odds ratio, 1.28; 1.08-1.52), immunocompromise (odds ratio, 1.23; 1.03-1.47), and coagulopathy (odds ratio, 1.23; 1.03-1.48). High-risk patients (≥ three risk factors) had 70% higher (CI, 48-96%) refractory risk (19% higher absolute risk; CI, 14-25%) versus low-risk (zero risk factors) patients. Initiating fluids in greater than 2 hours also predicted refractoriness (odds ratio, 1.96; CI, 1.49-2.58). Mortality was 15% higher (CI, 10-18%) for refractory patients. CONCLUSIONS: Two in three hypotensive sepsis patients were responsive to initial fluid resuscitation. Heart failure, hypothermia, immunocompromise, hyperlactemia, and coagulopathy were associated with the refractory phenotype. Fluid resuscitation initiated after the initial 2 hours more strongly predicted refractoriness than any patient factor tested.

Patterns and Outcomes Associated With Timeliness of Initial Crystalloid Resuscitation in a Prospective Sepsis and Septic Shock Cohort.

OBJECTIVES: The objectives of this study were to 1) assess patterns of early crystalloid resuscitation provided to sepsis and septic shock patients at initial presentation and 2) determine the association between time to initial crystalloid resuscitation with hospital mortality, mechanical ventilation, ICU utilization, and length of stay. DESIGN: Consecutive-sample observational cohort. SETTING: Nine tertiary and community hospitals over 1.5 years. PATIENTS: Adult sepsis and septic shock patients captured in a prospective quality improvement database inclusion criteria: suspected or confirmed infection, greater than or equal to two systemic inflammatory response criteria, greater than or equal to one organ-dysfunction criteria. INTERVENTIONS: The primary exposure was crystalloid initiation within 30 minutes or lesser, 31-120 minutes, or more than 120 minutes from sepsis identification. MEASUREMENTS AND MAIN RESULTS: We identified 11,182 patients. Crystalloid initiation was faster for emergency department patients (ß, -141 min; CI, -159 to -125; p < 0.001), baseline hypotension (ß, -39 min; CI, -48 to -32; p < 0.001), fever, urinary or skin/soft-tissue source of infection. Initiation was slower with heart failure (ß, 20 min; CI, 14-25; p < 0.001), and renal failure (ß, 16 min; CI, 10-22; p < 0.001). Five thousand three hundred thirty-six patients (48%) had crystalloid initiated in 30 minutes or lesser versus 2,388 (21%) in 31-120 minutes, and 3,458 (31%) in more than 120 minutes. The patients receiving fluids within 30 minutes had lowest mortality (949 [17.8%]) versus 31-120 minutes (446 [18.7%]) and more than 120 minutes (846 [24.5%]). Compared with more than 120 minutes, the adjusted odds ratio for mortality was 0.76 (CI, 0.64-0.90; p = 0.002) for 30 minutes or lesser and 0.76 (CI, 0.62-0.92; p = 0.004) for 31-120 minutes. When assessed continuously, mortality odds increased by 1.09 with each hour to initiation (CI, 1.03-1.16; p = 0.002). We observed similar patterns for mechanical ventilation, ICU utilization, and length of stay. We did not observe significant interaction for mortality risk between initiation time and baseline heart failure, renal failure, hypotension, acute kidney injury, altered gas exchange, or emergency department (vs inpatient) presentation. CONCLUSIONS: Crystalloid was initiated significantly later with comorbid heart failure and renal failure, with absence of fever or hypotension, and in inpatient-presenting sepsis. Earlier crystalloid initiation was associated with decreased mortality. Comorbidities and severity did not modify this effect.

Survival Benefit and Cost Savings From Compliance With a Simplified 3-Hour Sepsis Bundle in a Series of Prospective, Multisite, Observational Cohorts.

OBJECTIVES: To determine mortality and costs associated with adherence to an aggressive, 3-hour sepsis bundle versus noncompliance with greater than or equal to one bundle element for severe sepsis and septic shock patients. DESIGN: Prospective, multisite, observational study following three sequential, independent cohorts, from a single U.S. health system, through their hospitalization. SETTING: Cohort 1: five tertiary and six community hospitals. Cohort 2: single tertiary, academic medical center. Cohort 3: five tertiary and four community hospitals. PATIENTS: Consecutive sample of all severe sepsis and septic shock patients (defined: infection, ≥ 2 systemic inflammatory response syndrome, and hypoperfusive organ dysfunction) identified by a quality initiative. The exposure was full 3-hour bundle compliance. Bundle elements are as follows: 1) blood cultures before antibiotics; 2) parenteral antibiotics administered less than or equal to 180 minutes from greater than or equal to two systemic inflammatory response syndrome "and" lactate ordered, or less than or equal to 60 minutes from "time-zero," whichever occurs earlier; 3) lactate result available less than or equal to 90 minutes postorder; and 4) 30 mL/kg IV crystalloid bolus initiated less than or equal to 30 minutes from "time-zero." Main outcomes were in-hospital mortality (all cohorts) and total direct costs (cohorts 2 and 3). MEASUREMENTS AND MAIN RESULTS: Cohort 1: 5,819 total patients; 1,050 (18.0%) bundle compliant. Mortality: 604 (22.6%) versus 834 (26.5%); CI, 0.9-7.1%; adjusted odds ratio, 0.72; CI, 0.61-0.86; p value is less than 0.001. Cohort 2: 1,697 total patients; 739 (43.5%) bundle compliant. Mortality: 99 (13.4%) versus 171 (17.8%), CI, 1.0-7.9%; adjusted odds ratio, 0.60; CI, 0.44-0.80; p value is equal to 0.001. Mean costs: $14,845 versus $20,056; CI, -$4,798 to -5,624; adjusted ß, -$2,851; CI, -$4,880 to -822; p value is equal to 0.006. Cohort 3: 7,239 total patients; 2,115 (29.2%) bundle compliant. Mortality: 383 (18.1%) versus 1,078 (21.0%); CI, 0.9-4.9%; adjusted odds ratio, 0.84; CI, 0.73-0.96; p value is equal to 0.013. Mean costs: $17,885 versus $22,108; CI, -$2,783 to -5,663; adjusted ß, -$1,423; CI, -$2,574 to -272; p value is equal to 0.015. CONCLUSIONS: In three independent cohorts, 3-hour bundle compliance was associated with improved survival and cost savings.

Early sepsis bundle compliance for non-hypotensive patients with intermediate versus severe hyperlactemia.

OBJECTIVE: To compare the association of 3-h sepsis bundle compliance with hospital mortality in non-hypotensive sepsis patients with intermediate versus severe hyperlactemia. METHODS: This was a cohort study of all non-hypotensive, hyperlactemic sepsis patients captured in a prospective quality-improvement database, treated October 2014 to September 2015 at five tertiary-care centers. We defined sepsis as 1) infection, 2) ≥2 SIRS criteria, and 3) ≥1 organ dysfunction criterion. "Time-zero" was the first time a patient met all sepsis criteria. INCLUSION CRITERIA: systolic blood pressure>90 mmHg, mean arterial pressure>65 mmHg, and serum lactate≥2.2 mmol/L. Primary exposures: 1) intermediate(2.2-3.9 mmol/L) versus severe(≥4.0 mmol/L) hyperlactemia and 2) full 3-h bundle compliance. Bundle elements: The primary outcome was 60-day in-hospital mortality. RESULTS: 2417 patients met inclusion criteria. 704(29%) had lactate≥4.0 mmol/L versus 1775 patients with lactate 2.2-3.9 mmol/L. Compliance was 75% for antibiotics and 53% for fluids. Full-compliance was comparable between lactate groups (n=200(29%) and 488(28%), respectively). We observed 424(17.5%) mortalities: intermediate/non-compliant - 182(14.9%), intermediate/compliant - 41(8.4%), severe/non-compliant - 147(29.2%), severe/compliant - 54(27.0%) [difference-of-differences=4.3%, CI=2.6-5.9%]. In multivariable regression, mortality predictors included severe hyperlactemia (OR=1.99, CI=1.51-2.63) and bundle compliance (OR=0.62, CI=0.42-0.90), and their interaction was significant: p(interaction)=0.022. CONCLUSION: We observed a significant interaction between 3-h bundle compliance and initial hyperlactemia. Bundle compliance may be associated with greater mortality benefit for non-hypotensive sepsis patients with less severe hyperlactemia.

Left Ventricular Hypertrophy in Children with Hypertension: in Search of a Definition.

PURPOSE OF REVIEW: The purpose of this review is to provide background on the importance of left ventricular hypertrophy (LVH) in children with hypertension, to highlight various diagnostic modalities and measures for defining LVH, and to demonstrate the need for standardization and a consensus definition for LVH in the pediatric population. RECENT FINDINGS: There is no clear consensus among specialists performing echocardiograms and treating clinicians on the definition of LVH in children with hypertension. In fact, there is considerable variation in every step of the evaluation of pediatric LVH. There is variation in every step of the assessment of LVH in the pediatric population. This variation exists in imaging modality, the type of measurement used, the method of calculating left ventricular mass (LVM), the method of indexing LVM to body size, the normalization method for the index used, the reference data used, the inclusion of confounders, the implementation in clinical practice, and the format for echocardiography reporting.

Acute Kidney Injury in Neonates in the PICU.

OBJECTIVES: Acute kidney injury is an independent risk factor for morbidity and mortality in critically ill children in the PICU. Neonates are a particularly vulnerable subgroup regarding acute kidney injury. The objectives were to define the prevalence of acute kidney injury to assess independent risk factors, for the development of acute kidney injury, and to determine the impact of acute kidney injury on outcomes in critically ill neonates without history of cardiac surgery. DESIGN: A retrospective study of neonates (≤ 28 d old and ≥ 32 wk of gestational age) admitted to a tertiary PICU was conducted. Acute kidney injury was classified using the Kidney Disease: Improving Global Outcomes definition. SETTING: PICU in a tertiary children's hospital. PATIENTS: A total of 80 neonates (62% male neonates) with a median gestational age of 38 weeks (interquartile range, 37-39 wk) were reviewed. INTERVENTION: None. MEASUREMENT AND MAIN RESULTS: Acute kidney injury was found in 35% (n = 28) of neonates. Fourteen (50%) reached stage I, 8 (29%) stage II, and 6 (21%) stage III acute kidney injury. Younger age was associated with acute kidney injury (p = 0.016; odds ratio, 0.93; CI, 0.88-0.98). In regression analysis adjusted for age and gender, bacteremia (p = 0.014; odds ratio, 5.4; CI, 1.4-20.4) and maximum sodium concentration (p = 0.02; odds ratio, 1.12; CI, 1.02-1.24) were associated with acute kidney injury. Mortality (p = 0.03) and length of mechanical ventilation (p = 0.001) were significantly higher in neonates with acute kidney injury compared with those without acute kidney injury. In an adjusted regression model, stages 2 and 3 combined were associated with increased mortality (p = 0.02; odds ratio, 5.64; CI, 1.33-23.8), length of ventilation (p = 0.016; ß, 12.2; CI, 2.39-22.0), and length of stay (p = 0.049; ß, 12.2; CI, 0.073-24.3). CONCLUSIONS: Acute kidney injury is common in neonates not requiring cardiac surgery and is associated with increased morbidity and mortality. Age, bacteremia, and maximum sodium concentration are independently associated with the development of acute kidney injury in this population.