Feasibility and Safety of Intravenous Sotalol Loading in Adult Patients With Atrial Fibrillation (DASH-AF).

BACKGROUND: Inpatient initiation of sotalol is recommended owing to its proarrhythmic effects. OBJECTIVES: The DASH-AF (Feasibility and Safety of Intravenous Sotalol Administered as a Loading Dose to Initiate Oral Sotalol Therapy in Adult Patients With Atrial Fibrillation) trial evaluates the safety and feasibility of intravenous (IV) sotalol, achieving a steady state with maximum QTc prolongation within 6 hours instead of the traditional 5-dose inpatient oral (PO) titration. METHODS: DASH-AF is a prospective, nonrandomized, multicenter, open-label trial consisting of patients who underwent IV sotalol loading dose to initiate rapid oral therapy for atrial arrhythmias. IV dose was calculated based on the target oral dose as indicated by baseline QTc and renal function. Patients' QTc (in sinus) was measured via electrocardiography at 15-minute intervals and after IV loading completion. Patients were discharged 4 hours after first oral dose. All patients were monitored via mobile cardiac outpatient telemetry for 72 hours. The control group was composed of patients admitted for the traditional 5 PO doses. Safety outcomes were assessed in both groups. RESULTS: A total of 120 patients from 3 centers were enrolled from 2021 to 2022 in the IV loading group (compared with type of AF- and renal function-matched patients in the conventional PO loading cohort). This study demonstrated no significant change in ΔQTc in both groups, with a significantly lower number of patients requiring dose adjustment in the IV arm compared with the PO arm (4.1% vs 16.6%; P = 0.003). This led to potential cost savings of up to $3,500.68 per admission. CONCLUSIONS: The DASH-AF trial shows that rapid IV sotalol loading in atrial fibrillation/flutter patients for rhythm control is feasible and safe compared with conventional oral loading with significant cost reduction. (Feasibility and Safety of Intravenous Sotalol Administered as a Loading Dose to Initiate Oral Sotalol Therapy in Adult Patients With Atrial Fibrillation [DASH-AF]; NCT04473807).

Impaired Lymphocyte Responses in Pediatric Sepsis Vary by Pathogen Type and are Associated with Features of Immunometabolic Dysregulation.

BACKGROUND: Sepsis is the leading cause of death in hospitalized children worldwide. Despite its hypothesized immune-mediated mechanism, targeted immunotherapy for sepsis is not available for clinical use. OBJECTIVE: To determine the association between longitudinal cytometric, proteomic, bioenergetic, and metabolomic markers of immunometabolic dysregulation and pathogen type in pediatric sepsis. METHODS: Serial peripheral blood mononuclear cell (PBMC) samples were obtained from 14 sepsis patients (34 total samples) and 7 control patients for this observational study. Flow cytometry was used to define immunophenotype, including T cell subset frequency and activation state, and assess intracellular cytokine production. Global immune dysfunction was assessed by tumor necrosis factor-α (TNF-α) production capacity and monocyte human leukocyte antigen DR (HLA-DR) expression. Mitochondrial function was assessed by bulk respirometry. Plasma cytokine levels were determined via Luminex assay. Metabolites were measured by liquid chromatography-mass spectrometry. Results were compared by timepoint and pathogen type. RESULTS: Sepsis patients were older (15.9 years vs. 10.4 years, P = 0.02) and had higher illness severity by PRISM-III (12.0 vs. 2.0, P < 0.001) compared to controls; demographics were otherwise similar, though control patients were predominately male. Compared to controls, sepsis patients at timepoint 1 demonstrated lower monocyte HLA-DR expression (75% vs. 92%, P = 0.02), loss of peripheral of non-naïve CD4+ T cells (62.4% vs. 77.6%, P = 0.04), and reduced PBMC mitochondrial spare residual capacity (SRC; 4.0 pmol/s/106 cells vs. 8.4 pmol/s/106 cells, P = 0.01). At sepsis onset, immunoparalysis (defined as TNF-α production capacity < 200 pg/mL) was present in 39% of sepsis patients and not identified among controls. Metabolomic findings in sepsis patients were most pronounced at sepsis onset and included elevated uridine and 2-dehydrogluconate and depleted citrulline. Loss of peripheral non-naïve CD4+ T cells was associated with immune dysfunction and reduced cytokine production despite increased T cell activation. CD4+ T cell differentiation and corresponding pro- and anti-inflammatory cytokines varied by pathogen. CONCLUSION: Pediatric sepsis patients exhibit a complex, dynamic physiologic state characterized by impaired T cell function and immunometabolic dysregulation which varies by pathogen type.

Temperature Trajectory Sub-phenotypes and the Immuno-Inflammatory Response in Pediatric Sepsis.

OBJECTIVE: Heterogeneity has hampered sepsis trials, and sub-phenotyping may assist with enrichment strategies. However, biomarker-based strategies are difficult to operationalize. Four sub-phenotypes defined by distinct temperature trajectories in the first 72 h have been reported in adult sepsis. Given the distinct epidemiology of pediatric sepsis, the existence and relevance of temperature trajectory-defined sub-phenotypes in children is unknown. We aimed to classify septic children into de novo sub-phenotypes derived from temperature trajectories in the first 72 h, and compare cytokine, immune function, and immunometabolic markers across subgroups. METHODS: This was a secondary analysis of a prospective cohort of 191 critically ill septic children recruited from a single academic pediatric intensive care unit. We performed group-based trajectory modeling using temperatures over the first 72 h of sepsis to identify latent profiles. We then used mixed effects regression to determine if temperature trajectory-defined sub-phenotypes were associated with cytokine levels, immune function, and mitochondrial respiration. RESULTS: We identified four temperature trajectory-defined sub-phenotypes: hypothermic, normothermic, hyperthermic fast-resolvers, and hyperthermic slow-resolvers. Hypothermic patients were less often previously healthy and exhibited lower levels of pro- and anti-inflammatory cytokines and chemokines. Hospital mortality did not differ between hypothermic children (17%) and other sub-phenotypes (3-11%; P = 0.26). CONCLUSIONS: Critically ill septic children can be categorized into temperature trajectory-defined sub-phenotypes that parallel adult sepsis. Hypothermic children exhibit a blunted cytokine and chemokine profile. Group-based trajectory modeling has utility for identifying subtypes of clinical syndromes by incorporating readily available longitudinal data, rather than relying on inputs from a single timepoint.

Influence of Immune Cell Subtypes on Mitochondrial Measurements in Peripheral Blood Mononuclear Cells From Children with Sepsis.

INTRODUCTION: Peripheral blood mononuclear cells (PBMCs) are commonly used to compare mitochondrial function in patients with versus without sepsis, but how these measurements in this mixed cell population vary by composition of immune cell subtypes is not known, especially in children. We determined the effect of changing immune cell composition on PBMC mitochondrial respiration and content in children with and without sepsis. METHODS: PBMC mitochondrial respiration and citrate synthase (CS) activity, a marker of mitochondrial content, were measured in 167 children with sepsis at three timepoints (day 1-2, 3-5, and 8-14) and once in 19 nonseptic controls. The proportion of lymphocytes and monocytes and T, B, and NK cells was measured using flow cytometry. More specific CD4+ and CD8+ T cell subsets were measured from 13 sepsis patients and 6 controls. Spearman's correlation and simple and mixed effects linear regression were used to determine the association of PBMC mitochondrial measures with proportion of immune cell subtypes. RESULTS: PBMC mitochondrial respiration and CS activity were correlated with proportion of monocytes, lymphocytes, T B, and NK cells in controls, but not in sepsis patients. PBMC mitochondrial respiration was correlated with CD4+ and CD8+ T cell subsets in both groups. After controlling for differences in immune cell composition between groups using linear regression models, PBMC respiration and CS activity remained lower in sepsis patients than controls. CONCLUSIONS: Mitochondrial measurements from PBMCs varied with changes in immune cell composition in children with and without sepsis. However, differences in PBMC mitochondrial measurements between sepsis patients and controls were at least partially attributable to the effects of sepsis rather than solely an epiphenomena of variable immune cell composition.

Endothelial Biomarkers Are Associated With Indirect Lung Injury in Sepsis-Associated Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVES: Acute respiratory distress syndrome occurring in the setting of direct versus indirect lung injury may reflect different pathobiologies amenable to different treatment strategies. We sought to test whether a panel of plasma biomarkers differed between children with sepsis-associated direct versus indirect acute respiratory distress syndrome. We hypothesized that a biomarker profile indicative of endothelial activation would be associated with indirect acute respiratory distress syndrome. DESIGN: Observational cohort. SETTING: Academic PICU. SUBJECTS: Patients less than 18 years old with sepsis-associated direct (pneumonia, n = 52) or indirect (extrapulmonary sepsis, n = 46) acute respiratory distress syndrome. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 58 biomarkers examined, 33 differed by acute respiratory distress syndrome subtype. We used classification and regression tree methodology to examine associations between clinical and biochemical markers and acute respiratory distress syndrome subtype. The classification and regression tree model using only clinical variables (age, sex, race, oncologic comorbidity, and Pediatric Risk of Mortality-III score) performed worse than the classification and regression tree model using five clinical variables and 58 biomarkers. The best classification and regression tree model used only four endothelial biomarkers, including elevated angiopoietin-2/angiopoietin-1 ratio, vascular cell-adhesion molecule, and von Willebrand factor, to identify indirect acute respiratory distress syndrome. Test characteristics were 89% (80-97%) sensitivity, 80% (69-92%) specificity, positive predictive value 84% (74-93%), and negative predictive value 86% (76-96%). CONCLUSIONS: Indirect lung injury in children with acute respiratory distress syndrome is characterized by a biomarker profile indicative of endothelial activation, excess inflammation, and worse outcomes. A model using four biomarkers has the potential to be useful for more precisely identifying patients with acute respiratory distress syndrome whose pathobiology may respond to endothelial-targeted therapies in future trials.

Diagnostic biomarkers to differentiate sepsis from cytokine release syndrome in critically ill children.

Chimeric antigen receptor (CAR) T-cells directed against CD19 have drastically altered outcomes for children with relapsed and refractory acute lymphoblastic leukemia (r/r ALL). Pediatric patients with r/r ALL treated with CAR-T are at increased risk of both cytokine release syndrome (CRS) and sepsis. We sought to investigate the biologic differences between CRS and sepsis and to develop predictive models which could accurately differentiate CRS from sepsis at the time of critical illness. We identified 23 different cytokines that were significantly different between patients with sepsis and CRS. Using elastic net prediction modeling and tree classification, we identified cytokines that were able to classify subjects as having CRS or sepsis accurately. A markedly elevated interferon γ (IFNγ) or a mildly elevated IFNγ in combination with a low IL1ß were associated with CRS. A normal to mildly elevated IFNγ in combination with an elevated IL1ß was associated with sepsis. This combination of IFNγ and IL1ß was able to categorize subjects as having CRS or sepsis with 97% accuracy. As CAR-T therapies become more common, these data provide important novel information to better manage potential associated toxicities.

Systemic Endothelial Activation Is Associated With Early Acute Respiratory Distress Syndrome in Children With Extrapulmonary Sepsis.

OBJECTIVES: Systemic endothelial activation may contribute to sepsis-associated organ injury, including acute respiratory distress syndrome. We hypothesized that children with extrapulmonary sepsis with versus without acute respiratory distress syndrome would have plasma biomarkers indicative of increased endothelial activation and that persistent biomarker changes would be associated with poor outcome. DESIGN: Observational cohort. SETTING: Academic PICU. PATIENTS: Patients less than 18 years old with sepsis from extrapulmonary infection with (n = 46) or without (n = 54) acute respiratory distress syndrome and noninfected controls (n = 19). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Endothelial (angiopoietin-1, angiopoietin-2, tyrosine kinase with immunoglobulin-like loop epidermal growth factor homology domain 2, vascular endothelial growth factor, soluble fms-like tyrosine kinase, von Willebrand factor, E-selectin, intercellular adhesion molecule, vascular cell adhesion molecule, thrombomodulin) and inflammatory biomarkers (C-reactive protein, interleukin-6, and interleukin-8) were measured from peripheral plasma collected within 3 days (time 1) of sepsis recognition and at 3-6 days (time 2) and 7-14 days (time 3). Time 1 biomarkers and longitudinal measurements were compared for sepsis patients with versus without acute respiratory distress syndrome and in relation to complicated course, defined as greater than or equal to two organ dysfunctions at day 7 or death by day 28. Angiopoietin-2, angiopoietin-2/angiopoietin-1 ratio, tyrosine kinase with immunoglobulin-like loop epidermal growth factor homology domain 2, vascular endothelial growth factor, von Willebrand factor, E-selectin, intercellular adhesion molecule, vascular cell adhesion molecule, thrombomodulin, endocan, C-reactive protein, interleukin-6, and interleukin-8 were different between sepsis and noninfected control patients at time 1. Among patients with sepsis, those with acute respiratory distress syndrome had higher angiopoietin-2/angiopoietin-1 ratio, vascular endothelial growth factor, vascular cell adhesion molecule, thrombomodulin, endocan, interleukin-6, and interleukin-8 than those without acute respiratory distress syndrome (all p < 0.003). Angiopoietin-2 and angiopoietin-2/angiopoietin-1 ratio remained higher in sepsis with versus without acute respiratory distress syndrome after multivariable analyses. Time 1 measures of angiopoietin-2, angiopoietin-2/-1 ratio, von Willebrand factor, and endocan were indicative of complicated course in all sepsis patients (all area under the receiver operating curve ≥ 0.80). In sepsis without acute respiratory distress syndrome, soluble fms-like tyrosine kinase decreased more quickly and von Willebrand factor and thrombomodulin decreased more slowly in those with complicated course. CONCLUSIONS: Children with extrapulmonary sepsis with acute respiratory distress syndrome had plasma biomarkers indicative of greater systemic endothelial activation than those without acute respiratory distress syndrome. Several endothelial biomarkers measured near sepsis recognition were associated with complicated course, whereas longitudinal biomarker changes yielded prognostic information only in those without sepsis-associated acute respiratory distress syndrome.

Mitochondrial Dysfunction is Associated With an Immune Paralysis Phenotype in Pediatric Sepsis.

OBJECTIVE: Immune dysregulation is a defining feature of sepsis, but the role for mitochondria in the development of immunoparalysis in pediatric sepsis is not known. We sought to determine if mitochondrial dysfunction measured in peripheral blood mononuclear cells (PBMCs) is associated with immunoparalysis and systemic inflammation in children with sepsis. DESIGN: Prospective observational study. SETTING: Single-academic pediatric intensive care unit (PICU). PATIENTS: One hundred sixty-one children with sepsis/septic shock and 18 noninfected PICU controls. MEASUREMENTS AND MAIN RESULTS: Mitochondrial respiration in PBMCs, markers of immune function, and plasma cytokines were measured on days 1 to 2 (T1), 3 to 5 (T2), and 8 to 14 (T3) after sepsis recognition, and once for controls. Immunoparalysis was defined as whole-blood ex vivo lipopolysaccharide-induced tumor necrosis factor-alpha (TNF-α) ≤200 pg/mL or monocyte human leukocyte antigen-DR ≤30%. Mitochondrial respiration was lower in children with versus without immunoparalysis measured at the same timepoint. Mitochondrial respiration measured early (at T1 and T2) was also lower in those with immunoparalysis at T2 and T3, respectively. Although most patients with immunoparalysis exhibited low mitochondrial respiration, this metabolic finding was not specific to the immunoparalysis phenotype. Plasma cytokines, including IL-8, IL-10, TNF-α, and MCP-1, were highest in the subset of sepsis patients with immune paralysis or low mitochondrial respiration at T1. CONCLUSIONS: Children with sepsis had lower PBMC mitochondrial respiration when immunoparalysis was present compared with those without immunoparalysis. The subsets with immune paralysis and low mitochondrial respiration exhibited the highest levels of systemic inflammation.

Persistent Mitochondrial Dysfunction Linked to Prolonged Organ Dysfunction in Pediatric Sepsis.

OBJECTIVES: Limited data exist about the timing and significance of mitochondrial alterations in children with sepsis. We therefore sought to determine if alterations in mitochondrial respiration and content within circulating peripheral blood mononuclear cells were associated with organ dysfunction in pediatric sepsis. DESIGN: Prospective observational study SETTING:: Single academic PICU. PATIENTS: One-hundred sixty-seven children with sepsis/septic shock and 19 PICU controls without sepsis, infection, or organ dysfunction. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Mitochondrial respiration and content were measured in peripheral blood mononuclear cells on days 1-2, 3-5, and 8-14 after sepsis recognition or once for controls. Severity and duration of organ dysfunction were determined using the Pediatric Logistic Organ Dysfunction score and organ failure-free days through day 28. Day 1-2 maximal uncoupled respiration (9.7 ± 7.7 vs 13.7 ± 4.1 pmol O2/s/10 cells; p = 0.02) and spare respiratory capacity (an index of bioenergetic reserve: 6.2 ± 4.3 vs 9.6 ± 3.1; p = 0.005) were lower in sepsis than controls. Mitochondrial content, measured by mitochondrial DNA/nuclear DNA, was higher in sepsis on day 1-2 than controls (p = 0.04) and increased in sepsis patients who had improving spare respiratory capacity over time (p = 0.005). Mitochondrial respiration and content were not associated with day 1-2 Pediatric Logistic Organ Dysfunction score, but low spare respiratory capacity was associated with higher Pediatric Logistic Organ Dysfunction score on day 3-5. Persistently low spare respiratory capacity was predictive of residual organ dysfunction on day 14 (area under the receiver operating characteristic, 0.72; 95% CI, 0.61-0.84) and trended toward fewer organ failure-free days although day 28 (ß coefficient, -0.64; 95% CI, -1.35 to 0.06; p = 0.08). CONCLUSIONS: Mitochondrial respiration was acutely decreased in peripheral blood mononuclear cells in pediatric sepsis despite an increase in mitochondrial content. Over time, a rise in mitochondrial DNA tracked with improved respiration. Although initial mitochondrial alterations in peripheral blood mononuclear cells were unrelated to organ dysfunction, persistently low respiration was associated with slower recovery from organ dysfunction.

Site Variability in Regulatory Oversight for an International Study of Pediatric Sepsis.

OBJECTIVES: Duplicative institutional review board/research ethics committee review for multicenter studies may impose administrative burdens and inefficiencies affecting study implementation and quality. Understanding variability in site-specific institutional review board/research ethics committee assessment and barriers to using a single review committee (an increasingly proposed solution) can inform a more efficient process. We provide needed data about the regulatory oversight process for the Sepsis PRevalence, OUtcomes, and Therapies multicenter point prevalence study. DESIGN: Survey. SETTING: Sites invited to participate in Sepsis PRevalence, OUtcomes, and Therapies. SUBJECTS: Investigators at sites that expressed interest and/or participated in Sepsis PRevalence, OUtcomes, and Therapies. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Using an electronic survey, we collected data about 1) logistics of protocol submission, 2) institutional review board/research ethics committee requested modifications, and 3) use of a single institutional review board (for U.S. sites). We collected surveys from 104 of 167 sites (62%). Of the 97 sites that submitted the protocol for institutional review board/research ethics committee review, 34% conducted full board review, 54% expedited review, and 4% considered the study exempt. Time to institutional review board/research ethics committee approval required a median of 34 (range 3-186) days, which took longer at sites that required protocol modifications (median [interquartile range] 50 d [35-131 d] vs 32 d [14-54 d)]; p = 0.02). Enrollment was delayed at eight sites due to prolonged (> 50 d) time to approval. Of 49 U.S. sites, 43% considered using a single institutional review board, but only 18% utilized this option. Time to final approval for U.S. sites using the single institutional review board was 62 days (interquartile range, 34-70 d) compared with 34 days (interquartile range, 15-54 d) for nonsingle institutional review board sites (p = 0.16). CONCLUSIONS: Variability in regulatory oversight was evident for this minimal-risk observational research study, most notably in the category of type of review conducted. Duplicative review prolonged time to protocol approval at some sites. Use of a single institutional review board for U.S. sites was rare and did not improve efficiency of protocol approval. Suggestions for minimizing these challenges are provided.

The Epidemiology of Hospital Death Following Pediatric Severe Sepsis: When, Why, and How Children With Sepsis Die.

OBJECTIVE: The epidemiology of in-hospital death after pediatric sepsis has not been well characterized. We investigated the timing, cause, mode, and attribution of death in children with severe sepsis, hypothesizing that refractory shock leading to early death is rare in the current era. DESIGN: Retrospective observational study. SETTING: Emergency departments and ICUs at two academic children's hospitals. PATIENTS: Seventy-nine patients less than 18 years old treated for severe sepsis/septic shock in 2012-2013 who died prior to hospital discharge. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Time to death from sepsis recognition, cause and mode of death, and attribution of death to sepsis were determined from medical records. Organ dysfunction was assessed via daily Pediatric Logistic Organ Dysfunction-2 scores for 7 days preceding death with an increase greater than or equal to 5 defined as worsening organ dysfunction. The median time to death was 8 days (interquartile range, 1-12 d) with 25%, 35%, and 49% of cumulative deaths within 1, 3, and 7 days of sepsis recognition, respectively. The most common cause of death was refractory shock (34%), then multiple organ dysfunction syndrome after shock recovery (27%), neurologic injury (19%), single-organ respiratory failure (9%), and nonseptic comorbidity (6%). Early deaths (≤ 3 d) were mostly due to refractory shock in young, previously healthy patients while multiple organ dysfunction syndrome predominated after 3 days. Mode of death was withdrawal in 72%, unsuccessful cardiopulmonary resuscitation in 22%, and irreversible loss of neurologic function in 6%. Ninety percent of deaths were attributable to acute or chronic manifestations of sepsis. Only 23% had a rise in Pediatric Logistic Organ Dysfunction-2 that indicated worsening organ dysfunction. CONCLUSIONS: Refractory shock remains a common cause of death in pediatric sepsis, especially for early deaths. Later deaths were mostly attributable to multiple organ dysfunction syndrome, neurologic, and respiratory failure after life-sustaining therapies were limited. A pattern of persistent, rather than worsening, organ dysfunction preceded most deaths.

New or Progressive Multiple Organ Dysfunction Syndrome in Pediatric Severe Sepsis: A Sepsis Phenotype With Higher Morbidity and Mortality.

OBJECTIVES: To describe the epidemiology, morbidity, and mortality of new or progressive multiple organ dysfunction syndrome in children with severe sepsis. DESIGN: Secondary analysis of a prospective, cross-sectional, point prevalence study. SETTING: International, multicenter PICUs. PATIENTS: Pediatric patients with severe sepsis identified on five separate days over a 1-year period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 567 patients from 128 PICUs in 26 countries enrolled, 384 (68%) developed multiple organ dysfunction syndrome within 7 days of severe sepsis recognition. Three hundred twenty-seven had multiple organ dysfunction syndrome on the day of sepsis recognition. Ninety-one of these patients developed progressive multiple organ dysfunction syndrome, whereas an additional 57 patients subsequently developed new multiple organ dysfunction syndrome, yielding a total proportion with severe sepsis-associated new or progressive multiple organ dysfunction syndrome of 26%. Hospital mortality in patients with progressive multiple organ dysfunction syndrome was 51% compared with patients with new multiple organ dysfunction syndrome (28%) and those with single-organ dysfunction without multiple organ dysfunction syndrome (10%) (p < 0.001). Survivors of new or progressive multiple organ dysfunction syndrome also had a higher frequency of moderate to severe disability defined as a Pediatric Overall Performance Category score of greater than or equal to 3 and an increase of greater than or equal to 1 from baseline: 22% versus 29% versus 11% for progressive, new, and no multiple organ dysfunction syndrome, respectively (p < 0.001). CONCLUSIONS: Development of new or progressive multiple organ dysfunction syndrome is common (26%) in severe sepsis and is associated with a higher risk of morbidity and mortality than severe sepsis without new or progressive multiple organ dysfunction syndrome. Our data support the use of new or progressive multiple organ dysfunction syndrome as an important outcome in trials of pediatric severe sepsis although efforts are needed to validate whether reducing new or progressive multiple organ dysfunction syndrome leads to improvements in more definitive morbidity and mortality endpoints.

Comparison of Pediatric Severe Sepsis Managed in U.S. and European ICUs.

OBJECTIVES: Pediatric severe sepsis remains a significant global health problem without new therapies despite many multicenter clinical trials. We compared children managed with severe sepsis in European and U.S. PICUs to identify geographic variation, which may improve the design of future international studies. DESIGN: We conducted a secondary analysis of the Sepsis PRevalence, OUtcomes, and Therapies study. Data about PICU characteristics, patient demographics, therapies, and outcomes were compared. Multivariable regression models were used to determine adjusted differences in morbidity and mortality. SETTING: European and U.S. PICUs. PATIENTS: Children with severe sepsis managed in European and U.S. PICUs enrolled in the Sepsis PRevalence, OUtcomes, and Therapies study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: European PICUs had fewer beds (median, 11 vs 24; p < 0.001). European patients were younger (median, 1 vs 6 yr; p < 0.001), had higher severity of illness (median Pediatric Index of Mortality-3, 5.0 vs 3.8; p = 0.02), and were more often admitted from the ward (37% vs 24%). Invasive mechanical ventilation, central venous access, and vasoactive infusions were used more frequently in European patients (85% vs 68%, p = 0.002; 91% vs 82%, p = 0.05; and 71% vs 50%; p < 0.001, respectively). Raw morbidity and mortality outcomes were worse for European compared with U.S. patients, but after adjusting for patient characteristics, there were no significant differences in mortality, multiple organ dysfunction, disability at discharge, length of stay, or ventilator/vasoactive-free days. CONCLUSIONS: Children with severe sepsis admitted to European PICUs have higher severity of illness, are more likely to be admitted from hospital wards, and receive more intensive care therapies than in the United States. The lack of significant differences in morbidity and mortality after adjusting for patient characteristics suggests that the approach to care between regions, perhaps related to PICU bed availability, needs to be considered in the design of future international clinical trials in pediatric severe sepsis.

Discordant identification of pediatric severe sepsis by research and clinical definitions in the SPROUT international point prevalence study.

INTRODUCTION: Consensus criteria for pediatric severe sepsis have standardized enrollment for research studies. However, the extent to which critically ill children identified by consensus criteria reflect physician diagnosis of severe sepsis, which underlies external validity for pediatric sepsis research, is not known. We sought to determine the agreement between physician diagnosis and consensus criteria to identify pediatric patients with severe sepsis across a network of international pediatric intensive care units (PICUs). METHODS: We conducted a point prevalence study involving 128 PICUs in 26 countries across 6 continents. Over the course of 5 study days, 6925 PICU patients <18 years of age were screened, and 706 with severe sepsis defined either by physician diagnosis or on the basis of 2005 International Pediatric Sepsis Consensus Conference consensus criteria were enrolled. The primary endpoint was agreement of pediatric severe sepsis between physician diagnosis and consensus criteria as measured using Cohen's κ. Secondary endpoints included characteristics and clinical outcomes for patients identified using physician diagnosis versus consensus criteria. RESULTS: Of the 706 patients, 301 (42.6%) met both definitions. The inter-rater agreement (κ ± SE) between physician diagnosis and consensus criteria was 0.57 ± 0.02. Of the 438 patients with a physician's diagnosis of severe sepsis, only 69% (301 of 438) would have been eligible to participate in a clinical trial of pediatric severe sepsis that enrolled patients based on consensus criteria. Patients with physician-diagnosed severe sepsis who did not meet consensus criteria were younger and had lower severity of illness and lower PICU mortality than those meeting consensus criteria or both definitions. After controlling for age, severity of illness, number of comorbid conditions, and treatment in developed versus resource-limited regions, patients identified with severe sepsis by physician diagnosis alone or by consensus criteria alone did not have PICU mortality significantly different from that of patients identified by both physician diagnosis and consensus criteria. CONCLUSIONS: Physician diagnosis of pediatric severe sepsis achieved only moderate agreement with consensus criteria, with physicians diagnosing severe sepsis more broadly. Consequently, the results of a research study based on consensus criteria may have limited generalizability to nearly one-third of PICU patients diagnosed with severe sepsis.

Global epidemiology of pediatric severe sepsis: the sepsis prevalence, outcomes, and therapies study.

RATIONALE: Limited data exist about the international burden of severe sepsis in critically ill children. OBJECTIVES: To characterize the global prevalence, therapies, and outcomes of severe sepsis in pediatric intensive care units to better inform interventional trials. METHODS: A point prevalence study was conducted on 5 days throughout 2013-2014 at 128 sites in 26 countries. Patients younger than 18 years of age with severe sepsis as defined by consensus criteria were included. Outcomes were severe sepsis point prevalence, therapies used, new or progressive multiorgan dysfunction, ventilator- and vasoactive-free days at Day 28, functional status, and mortality. MEASUREMENTS AND MAIN RESULTS: Of 6,925 patients screened, 569 had severe sepsis (prevalence, 8.2%; 95% confidence interval, 7.6-8.9%). The patients' median age was 3.0 (interquartile range [IQR], 0.7-11.0) years. The most frequent sites of infection were respiratory (40%) and bloodstream (19%). Common therapies included mechanical ventilation (74% of patients), vasoactive infusions (55%), and corticosteroids (45%). Hospital mortality was 25% and did not differ by age or between developed and resource-limited countries. Median ventilator-free days were 16 (IQR, 0-25), and vasoactive-free days were 23 (IQR, 12-28). Sixty-seven percent of patients had multiorgan dysfunction at sepsis recognition, with 30% subsequently developing new or progressive multiorgan dysfunction. Among survivors, 17% developed at least moderate disability. Sample sizes needed to detect a 5-10% absolute risk reduction in outcomes within interventional trials are estimated between 165 and 1,471 [corrected] patients per group. CONCLUSIONS: Pediatric severe sepsis remains a burdensome public health problem, with prevalence, morbidity, and mortality rates similar to those reported in critically ill adult populations. International clinical trials targeting children with severe sepsis are warranted.

Understanding the global epidemiology of pediatric critical illness: the power, pitfalls, and practicalities of point prevalence studies.

OBJECTIVE: The point prevalence methodology is a valuable epidemiological study design that can optimize patient enrollment, prospectively gather individual-level data, and measure practice variability across a large number of geographic regions and healthcare settings. The objective of this article is to review the design, implementation, and analysis of recent point prevalence studies investigating the global epidemiology of pediatric critical illness. DATA SOURCES: Literature review and primary datasets. STUDY SELECTION: Multicenter, international point prevalence studies performed in PICUs since 2007. DATA EXTRACTION: Study topic, number of sites, number of study days, patients screened, prevalence of disease, use of specified therapies, and outcomes. DATA SYNTHESIS: Since 2007, five-point prevalence studies have been performed on acute lung injury, neurologic disease, thromboprophylaxis, fluid resuscitation, and sepsis in PICUs. These studies were performed in 59-120 sites in 7-28 countries. All studies accounted for seasonal variation in pediatric disease by collecting data over multiple study days. Studies screened up to 6,317 patients and reported data on prevalence and therapeutic variability. Three studies also reported short-term outcomes, a valuable but atypical data element in point prevalence studies. Using these five studies as examples, the advantages and disadvantages and approach to designing, implementing, and analyzing point prevalence studies are reviewed. CONCLUSIONS: Point prevalence studies in pediatric critical care can efficiently provide valuable insight on the global epidemiology of disease and practice patterns for critically ill children.

Bronchodilator responsiveness in swine veterinarians.

OBJECTIVE: Swine veterinarians are known to be at risk for respiratory symptoms and airflow obstruction. The present study reassessed the prevalence of respiratory complaints and pulmonary function abnormalities in swine veterinarians and sought to characterize their response to bronchodilators. METHODS: A cross-sectional study was conducted during the American Association of Swine Veterinarians annual meeting. Subjects completed a respiratory symptom and workplace exposure history questionnaire and spirometry. Subjects with airflow obstruction were assessed for a post-bronchodilator response with beta2 agonist administration. RESULTS: Participants included 58 veterinarians (mean age, 45.5 years). Work-related symptoms assessed by questionnaire included rhinitis symptoms (60.3%), cough and chest tightness (55.2%), and wheezing (35.1%). Airflow obstruction was detected in 11/58 (19%) of subjects by spirometry. Only 2/9 (22.2%) met American Thoracic Society criteria for reversibility with bronchodilator administration. CONCLUSIONS: Respiratory symptoms and airway obstruction remain common findings in swine veterinarians. Airflow obstruction was not consistently reversible with beta agonists, suggesting that swine barn exposure may be a risk factor for irreversible airflow obstruction.