Epinephrine Dosing Intervals Are Associated With Pediatric In-Hospital Cardiac Arrest Outcomes: A Multicenter Study.

OBJECTIVES: Data to support epinephrine dosing intervals during cardiopulmonary resuscitation (CPR) are conflicting. The objective of this study was to evaluate the association between epinephrine dosing intervals and outcomes. We hypothesized that dosing intervals less than 3 minutes would be associated with improved neurologic survival compared with greater than or equal to 3 minutes. DESIGN: This study is a secondary analysis of The ICU-RESUScitation Project (NCT028374497), a multicenter trial of a quality improvement bundle of physiology-directed CPR training and post-cardiac arrest debriefing. SETTING: Eighteen PICUs and pediatric cardiac ICUs in the United States. PATIENTS: Subjects were 18 years young or younger and 37 weeks old or older corrected gestational age who had an index cardiac arrest. Patients who received less than two doses of epinephrine, received extracorporeal CPR, or had dosing intervals greater than 8 minutes were excluded. INTERVENTIONS: The primary exposure was an epinephrine dosing interval of less than 3 vs. greater than or equal to 3 minutes. MEASUREMENTS AND MAIN RESULTS: The primary outcome was survival to discharge with a favorable neurologic outcome defined as a Pediatric Cerebral Performance Category score of 1-2 or no change from baseline. Regression models evaluated the association between dosing intervals and: 1) survival outcomes and 2) CPR duration. Among 382 patients meeting inclusion and exclusion criteria, median age was 0.9 years (interquartile range 0.3-7.6 yr) and 45% were female. After adjustment for confounders, dosing intervals less than 3 minutes were not associated with survival with favorable neurologic outcome (adjusted relative risk [aRR], 1.10; 95% CI, 0.84-1.46; p = 0.48) but were associated with improved sustained return of spontaneous circulation (ROSC) (aRR, 1.21; 95% CI, 1.07-1.37; p < 0.01) and shorter CPR duration (adjusted effect estimate, -9.5 min; 95% CI, -14.4 to -4.84 min; p < 0.01). CONCLUSIONS: In patients receiving at least two doses of epinephrine, dosing intervals less than 3 minutes were not associated with neurologic outcome but were associated with sustained ROSC and shorter CPR duration.

Evolution of Pediatric Critical Care Medicine Physicians Clinical and Academic Profile by Gender.

OBJECTIVES: To examine career trajectory and academic profile of Pediatric Critical Care Medicine (PCCM) physicians, with special focus on gender differences. DESIGN: Observational cross-sectional study of PCCM fellowship graduates using publicly available data. SETTING: Publicly available databases including National Provider Identifier registry, American Board of Pediatrics, Doximity, official hospital websites, and Scopus. SUBJECTS: Two thousand one hundred twenty-nine PCCM fellowship graduates employed in clinical positions in U.S. practice locations. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Physician demographic characteristics included gender and time since fellowship completion. Current career and academic characteristics included employment data, publication productivity (h-index), and academic rank. Data from 2129 career PCCM physicians was included, with recent graduates showing a notable increase in female representation. Workplace characteristics revealed that most PCCM physicians worked in university-affiliated hospitals, with higher percentages of female physicians working in university-affiliated hospitals compared with male physicians. The study also highlighted significant gender disparities in academic metrics, with male physicians having higher h-indices (3 vs. 2; p < 0.001) and more publications (6 vs. 4; p < 0.001) than their female counterparts across various career phases. Additionally, the analysis showed gender differences in academic rank, with a higher proportion of female faculty holding assistant and associate professor ranks (58.2% vs. 47.5%; p < 0.001), while a greater percentage of male faculty held the rank of professor (20.2% vs. 11.1%; p < 0.001). Multiple variable regression analysis identified both male gender and time since fellowship graduation as independently associated with a physician's h-index, while only time since fellowship graduation was linked to current academic rank. CONCLUSIONS: This is the first analysis of career and academic characteristics of practicing PCCM physicians, additionally studying the association of gender and career trajectory. Gender discrepancy was seen in employment hospital characteristics, h-indices, and academic rank. Additional studies are required to further explore the impact of gender on career trajectory.

Healthcare Burden and Resource Utilization After Pediatric Acute Respiratory Distress Syndrome: A Secondary Analysis of the Collaborative Pediatric Critical Care Research Network Acute Respiratory Distress Syndrome Study.

OBJECTIVES: To describe family healthcare burden and health resource utilization in pediatric survivors of acute respiratory distress syndrome (ARDS) at 3 and 9 months. DESIGN: Secondary analysis of a prospective multisite cohort study. SETTING: Eight academic PICUs in the United States (2019-2020). PATIENTS: Critically ill children with ARDS and follow-up survey data collected at 3 and/or 9 months after the event. INTERVENTIONS: None. METHODS AND MEASUREMENT: We evaluated family healthcare burden, a measure of healthcare provided by families at home, and child health resource use including medication use and emergency department (ED) and hospital readmissions during the initial 3- and 9-month post-ARDS using proxy-report. Using multivariable logistic regression, we evaluated patient characteristics associated with family healthcare burden at 3 months. MAIN RESULTS: Of 109 eligible patients, 74 (68%) and 63 patients (58%) had follow-up at 3- and 9-month post-ARDS. At 3 months, 46 families (62%) reported healthcare burden including (22%) with unmet care coordination needs. At 9 months, 33 families (52%) reported healthcare burden including 10 families (16%) with unmet care coordination needs. At month 3, 61 patients (82%) required prescription medications, 13 patients (18%) had ED visits and 16 patients (22%) required hospital readmission. At month 9, 41 patients (65%) required prescription medications, 19 patients (30%) had ED visits, and 16 (25%) required hospital readmission were reported. Medication use was associated with family healthcare burden at both 3 and 9 months. In a multivariable analysis, preillness functional status and chronic conditions were associated with healthcare burden at month 3 but illness characteristics were not. CONCLUSIONS: Pediatric ARDS survivors report high rates of healthcare burden and health resource utilization at 3- and 9-month post-ARDS. Future studies should assess the impact of improved care coordination to simplify care (e.g., medication management) and improve family burden.

Viral Detection by Reverse Transcriptase Polymerase Chain Reaction in Upper Respiratory Tract and Metagenomic RNA Sequencing in Lower Respiratory Tract in Critically Ill Children With Suspected Lower Respiratory Tract Infection.

OBJECTIVES: Viral lower respiratory tract infection (vLRTI) contributes to substantial morbidity and mortality in children. Diagnosis is typically confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) of nasopharyngeal specimens in hospitalized patients; however, it is unknown whether nasopharyngeal detection accurately reflects presence of virus in the lower respiratory tract (LRT). This study evaluates agreement between viral detection from nasopharyngeal specimens by RT-PCR compared with metagenomic next-generation RNA sequencing (RNA-Seq) from tracheal aspirates (TAs). DESIGN: This is an analysis of of a seven-center prospective cohort study. SETTING: Seven PICUs within academic children's hospitals in the United States. PATIENTS: Critically ill children (from 1 mo to 18 yr) who required mechanical ventilation via endotracheal tube for greater than or equal to 72 hours. INTERVENTIONS: We evaluated agreement in viral detection between paired upper and LRT samples. Results of clinical nasopharyngeal RT-PCR were compared with TA RNA-Seq. Positive and negative predictive agreement and Cohen's Kappa were used to assess agreement. MEASUREMENTS AND MAIN RESULTS: Of 295 subjects with paired testing available, 200 (68%) and 210 (71%) had positive viral testing by RT-PCR from nasopharyngeal and RNA-Seq from TA samples, respectively; 184 (62%) were positive by both nasopharyngeal RT-PCR and TA RNA-Seq for a virus, and 69 (23%) were negative by both methods. Nasopharyngeal RT-PCR detected the most abundant virus identified by RNA-Seq in 92.4% of subjects. Among the most frequent viruses detected, respiratory syncytial virus demonstrated the highest degree of concordance (κ = 0.89; 95% CI, 0.83-0.94), whereas rhinovirus/enterovirus demonstrated lower concordance (κ = 0.55; 95% CI, 0.44-0.66). Nasopharyngeal PCR was more likely to detect multiple viruses than TA RNA-Seq (54 [18.3%] vs 24 [8.1%], p ≤ 0.001). CONCLUSIONS: Viral nucleic acid detection in the upper versus LRT reveals good overall agreement, but concordance depends on the virus. Further studies are indicated to determine the utility of LRT sampling or the use of RNA-Seq to determine LRTI etiology.

Survival With Favorable Neurologic Outcome and Quality of Cardiopulmonary Resuscitation Following In-Hospital Cardiac Arrest in Children With Cardiac Disease Compared With Noncardiac Disease.

OBJECTIVES: To assess associations between outcome and cardiopulmonary resuscitation (CPR) quality for in-hospital cardiac arrest (IHCA) in children with medical cardiac, surgical cardiac, or noncardiac disease. DESIGN: Secondary analysis of a multicenter cluster randomized trial, the ICU-RESUScitation Project (NCT02837497, 2016-2021). SETTING: Eighteen PICUs. PATIENTS: Children less than or equal to 18 years old and greater than or equal to 37 weeks postconceptual age receiving chest compressions (CC) of any duration during the study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 1,100 children with IHCA, there were 273 medical cardiac (25%), 383 surgical cardiac (35%), and 444 noncardiac (40%) cases. Favorable neurologic outcome was defined as no more than moderate disability or no worsening from baseline Pediatric Cerebral Performance Category at discharge. The medical cardiac group had lower odds of survival with favorable neurologic outcomes compared with the noncardiac group (48% vs 55%; adjusted odds ratio [aOR] [95% CI], aOR 0.59 [95% CI, 0.39-0.87], p = 0.008) and surgical cardiac group (48% vs 58%; aOR 0.64 [95% CI, 0.45-0.9], p = 0.01). We failed to identify a difference in favorable outcomes between surgical cardiac and noncardiac groups. We also failed to identify differences in CC rate, CC fraction, ventilation rate, intra-arrest average target diastolic or systolic blood pressure between medical cardiac versus noncardiac, and surgical cardiac versus noncardiac groups. The surgical cardiac group had lower odds of achieving target CC depth compared to the noncardiac group (OR 0.15 [95% CI, 0.02-0.52], p = 0.001). We failed to identify a difference in the percentage of patients achieving target CC depth when comparing medical cardiac versus noncardiac groups. CONCLUSIONS: In pediatric IHCA, medical cardiac patients had lower odds of survival with favorable neurologic outcomes compared with noncardiac and surgical cardiac patients. We failed to find differences in CPR quality between medical cardiac and noncardiac patients, but there were lower odds of achieving target CC depth in surgical cardiac compared to noncardiac patients.

Early Cardiac Arrest Hemodynamics, End-Tidal C o2 , and Outcome in Pediatric Extracorporeal Cardiopulmonary Resuscitation: Secondary Analysis of the ICU-RESUScitation Project Dataset (2016-2021).

OBJECTIVES: Cannulation for extracorporeal membrane oxygenation during active extracorporeal cardiopulmonary resuscitation (ECPR) is a method to rescue patients refractory to standard resuscitation. We hypothesized that early arrest hemodynamics and end-tidal C o2 (ET co2 ) are associated with survival to hospital discharge with favorable neurologic outcome in pediatric ECPR patients. DESIGN: Preplanned, secondary analysis of pediatric Utstein, hemodynamic, and ventilatory data in ECPR patients collected during the 2016-2021 Improving Outcomes from Pediatric Cardiac Arrest study; the ICU-RESUScitation Project (ICU-RESUS; NCT02837497). SETTING: Eighteen ICUs participated in ICU-RESUS. PATIENTS: There were 97 ECPR patients with hemodynamic waveforms during cardiopulmonary resuscitation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Overall, 71 of 97 patients (73%) were younger than 1 year old, 82 of 97 (85%) had congenital heart disease, and 62 of 97 (64%) were postoperative cardiac surgical patients. Forty of 97 patients (41%) survived with favorable neurologic outcome. We failed to find differences in diastolic or systolic blood pressure, proportion achieving age-based target diastolic or systolic blood pressure, or chest compression rate during the initial 10 minutes of CPR between patients who survived with favorable neurologic outcome and those who did not. Thirty-five patients had ET co2 data; of 17 survivors with favorable neurologic outcome, four of 17 (24%) had an average ET co2 less than 10 mm Hg and two (12%) had a maximum ET co2 less than 10 mm Hg during the initial 10 minutes of resuscitation. CONCLUSIONS: We did not identify an association between early hemodynamics achieved by high-quality CPR and survival to hospital discharge with favorable neurologic outcome after pediatric ECPR. Candidates for ECPR with ET co2 less than 10 mm Hg may survive with favorable neurologic outcome.

Early, Persistent Lymphopenia Is Associated With Prolonged Multiple Organ Failure and Mortality in Septic Children.

OBJECTIVES: Sepsis-associated immune suppression correlates with poor outcomes. Adult trials are evaluating immune support therapies. Limited data exist to support consideration of immunomodulation in pediatric sepsis. We tested the hypothesis that early, persistent lymphopenia predicts worse outcomes in pediatric severe sepsis. DESIGN: Observational cohort comparing children with severe sepsis and early, persistent lymphopenia (absolute lymphocyte count < 1,000 cells/µL on 2 d between study days 0-5) to children without. The composite outcome was prolonged multiple organ dysfunction syndrome (MODS, organ dysfunction beyond day 7) or PICU mortality. SETTING: Nine PICUs in the National Institutes of Health Collaborative Pediatric Critical Care Research Network between 2015 and 2017. PATIENTS: Children with severe sepsis and indwelling arterial and/or central venous catheters. INTERVENTIONS: Blood sampling and clinical data analysis. MEASUREMENTS AND MAIN RESULTS: Among 401 pediatric patients with severe sepsis, 152 (38%) had persistent lymphopenia. These patients were older, had higher illness severity, and were more likely to have underlying comorbidities including solid organ transplant or malignancy. Persistent lymphopenia was associated with the composite outcome prolonged MODS or PICU mortality (66/152, 43% vs 45/249, 18%; p < 0.01) and its components prolonged MODS (59/152 [39%] vs 43/249 [17%]), and PICU mortality (32/152, 21% vs 12/249, 5%; p < 0.01) versus children without. After adjusting for baseline factors at enrollment, the presence of persistent lymphopenia was associated with an odds ratio of 2.98 (95% CI [1.85-4.02]; p < 0.01) for the composite outcome. Lymphocyte count trajectories showed that patients with persistent lymphopenia generally did not recover lymphocyte counts during the study, had lower nadir whole blood tumor necrosis factor-α response to lipopolysaccharide stimulation, and higher maximal inflammatory markers (C-reactive protein and ferritin) during days 0-3 ( p < 0.01). CONCLUSIONS: Children with severe sepsis and persistent lymphopenia are at risk of prolonged MODS or PICU mortality. This evidence supports testing therapies for pediatric severe sepsis patients risk-stratified by early, persistent lymphopenia.

Diastolic Blood Pressure Threshold During Pediatric Cardiopulmonary Resuscitation and Survival Outcomes: A Multicenter Validation Study.

OBJECTIVES: Arterial diastolic blood pressure (DBP) greater than 25 mm Hg in infants and greater than 30 mm Hg in children greater than 1 year old during cardiopulmonary resuscitation (CPR) was associated with survival to hospital discharge in one prospective study. We sought to validate these potential hemodynamic targets in a larger multicenter cohort. DESIGN: Prospective observational study. SETTING: Eighteen PICUs in the ICU-RESUScitation prospective trial from October 2016 to March 2020. PATIENTS: Children less than or equal to 18 years old with CPR greater than 30 seconds and invasive blood pressure (BP) monitoring during CPR. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Invasive BP waveform data and Utstein-style CPR data were collected, including prearrest patient characteristics, intra-arrest interventions, and outcomes. Primary outcome was survival to hospital discharge, and secondary outcomes were return of spontaneous circulation (ROSC) and survival to hospital discharge with favorable neurologic outcome. Multivariable Poisson regression models with robust error estimates evaluated the association of DBP greater than 25 mm Hg in infants and greater than 30 mm Hg in older children with these outcomes. Among 1,129 children with inhospital cardiac arrests, 413 had evaluable DBP data. Overall, 85.5% of the patients attained thresholds of mean DBP greater than or equal to 25 mm Hg in infants and greater than or equal to 30 mm Hg in older children. Initial return of circulation occurred in 91.5% and 25% by placement on extracorporeal membrane oxygenator. Survival to hospital discharge occurred in 58.6%, and survival with favorable neurologic outcome in 55.4% (i.e. 94.6% of survivors had favorable neurologic outcomes). Mean DBP greater than 25 mm Hg for infants and greater than 30 mm Hg for older children was significantly associated with survival to discharge (adjusted relative risk [aRR], 1.32; 1.01-1.74; p = 0.03) and ROSC (aRR, 1.49; 1.12-1.97; p = 0.002) but did not reach significance for survival to hospital discharge with favorable neurologic outcome (aRR, 1.30; 0.98-1.72; p = 0.051). CONCLUSIONS: These validation data demonstrate that achieving mean DBP during CPR greater than 25 mm Hg for infants and greater than 30 mm Hg for older children is associated with higher rates of survival to hospital discharge, providing potential targets for DBP during CPR.

Tobacco smoke exposure, the lower airways microbiome and outcomes of ventilated children.

BACKGROUND: Tobacco smoke exposure increases the risk and severity of lower respiratory tract infections in children, yet the mechanisms remain unclear. We hypothesized that tobacco smoke exposure would modify the lower airway microbiome. METHODS: Secondary analysis of a multicenter cohort of 362 children between ages 31 days and 18 years mechanically ventilated for >72 h. Tracheal aspirates from 298 patients, collected within 24 h of intubation, were evaluated via 16 S ribosomal RNA sequencing. Smoke exposure was determined by creatinine corrected urine cotinine levels ≥30 µg/g. RESULTS: Patients had a median age of 16 (IQR 568) months. The most common admission diagnosis was lower respiratory tract infection (53%). Seventy-four (20%) patients were smoke exposed and exhibited decreased richness and Shannon diversity. Smoke exposed children had higher relative abundances of Serratia spp., Moraxella spp., Haemophilus spp., and Staphylococcus aureus. Differences were most notable in patients with bacterial and viral respiratory infections. There were no differences in development of acute respiratory distress syndrome, days of mechanical ventilation, ventilator free days at 28 days, length of stay, or mortality. CONCLUSION: Among critically ill children requiring prolonged mechanical ventilation, tobacco smoke exposure is associated with decreased richness and Shannon diversity and change in microbial communities. IMPACT: Tobacco smoke exposure is associated with changes in the lower airways microbiome but is not associated with clinical outcomes among critically ill pediatric patients requiring prolonged mechanical ventilation. This study is among the first to evaluate the impact of tobacco smoke exposure on the lower airway microbiome in children. This research helps elucidate the relationship between tobacco smoke exposure and the lower airway microbiome and may provide a possible mechanism by which tobacco smoke exposure increases the risk for poor outcomes in children.

Hyperferritinemic sepsis, macrophage activation syndrome, and mortality in a pediatric research network: a causal inference analysis.

BACKGROUND: One of five global deaths are attributable to sepsis. Hyperferritinemic sepsis (> 500 ng/mL) is associated with increased mortality in single-center studies. Our pediatric research network's objective was to obtain rationale for designing anti-inflammatory clinical trials targeting hyperferritinemic sepsis. METHODS: We assessed differences in 32 cytokines, immune depression (low whole blood ex vivo TNF response to endotoxin) and thrombotic microangiopathy (low ADAMTS13 activity) biomarkers, seven viral DNAemias, and macrophage activation syndrome (MAS) defined by combined hepatobiliary dysfunction and disseminated intravascular coagulation, and mortality in 117 children with hyperferritinemic sepsis (ferritin level > 500 ng/mL) compared to 280 children with sepsis without hyperferritinemia. Causal inference analysis of these 41 variables, MAS, and mortality was performed. RESULTS: Mortality was increased in children with hyperferritinemic sepsis (27/117, 23% vs 16/280, 5.7%; Odds Ratio = 4.85, 95% CI [2.55-9.60]; z = 4.728; P-value < 0.0001). Hyperferritinemic sepsis had higher C-reactive protein, sCD163, IL-22, IL-18, IL-18 binding protein, MIG/CXCL9, IL-1ß, IL-6, IL-8, IL-10, IL-17a, IFN-γ, IP10/CXCL10, MCP-1/CCL2, MIP-1α, MIP-1ß, TNF, MCP-3, IL-2RA (sCD25), IL-16, M-CSF, and SCF levels; lower ADAMTS13 activity, sFasL, whole blood ex vivo TNF response to endotoxin, and TRAIL levels; more Adenovirus, BK virus, and multiple virus DNAemias; and more MAS (P-value < 0.05). Among these variables, only MCP-1/CCL2 (the monocyte chemoattractant protein), MAS, and ferritin levels were directly causally associated with mortality. MCP-1/CCL2 and hyperferritinemia showed direct causal association with depressed ex vivo whole blood TNF response to endotoxin. MCP-1/CCL2 was a mediator of MAS. MCP-1/CCL2 and MAS were mediators of hyperferritinemia. CONCLUSIONS: These findings establish hyperferritinemic sepsis as a high-risk condition characterized by increased cytokinemia, viral DNAemia, thrombotic microangiopathy, immune depression, macrophage activation syndrome, and death. The causal analysis provides rationale for designing anti-inflammatory trials that reduce macrophage activation to improve survival and enhance infection clearance in pediatric hyperferritinemic sepsis.

Identification of post-cardiac arrest blood pressure thresholds associated with outcomes in children: an ICU-Resuscitation study.

INTRODUCTION: Though early hypotension after pediatric in-hospital cardiac arrest (IHCA) is associated with inferior outcomes, ideal post-arrest blood pressure (BP) targets have not been established. We aimed to leverage prospectively collected BP data to explore the association of post-arrest BP thresholds with outcomes. We hypothesized that post-arrest systolic and diastolic BP thresholds would be higher than the currently recommended post-cardiopulmonary resuscitation BP targets and would be associated with higher rates of survival to hospital discharge. METHODS: We performed a secondary analysis of prospectively collected BP data from the first 24 h following return of circulation from index IHCA events enrolled in the ICU-RESUScitation trial (NCT02837497). The lowest documented systolic BP (SBP) and diastolic BP (DBP) were percentile-adjusted for age, height and sex. Receiver operator characteristic curves and cubic spline analyses controlling for illness category and presence of pre-arrest hypotension were generated exploring the association of lowest post-arrest SBP and DBP with survival to hospital discharge and survival to hospital discharge with favorable neurologic outcome (Pediatric Cerebral Performance Category of 1-3 or no change from baseline). Optimal cutoffs for post-arrest BP thresholds were based on analysis of receiver operator characteristic curves and spline curves. Logistic regression models accounting for illness category and pre-arrest hypotension examined the associations of these thresholds with outcomes. RESULTS: Among 693 index events with 0-6 h post-arrest BP data, identified thresholds were: SBP > 10th percentile and DBP > 50th percentile for age, sex and height. Fifty-one percent (n = 352) of subjects had lowest SBP above threshold and 50% (n = 346) had lowest DBP above threshold. SBP and DBP above thresholds were each associated with survival to hospital discharge (SBP: aRR 1.21 [95% CI 1.10, 1.33]; DBP: aRR 1.23 [1.12, 1.34]) and survival to hospital discharge with favorable neurologic outcome (SBP: aRR 1.22 [1.10, 1.35]; DBP: aRR 1.27 [1.15, 1.40]) (all p < 0.001). CONCLUSIONS: Following pediatric IHCA, subjects had higher rates of survival to hospital discharge and survival to hospital discharge with favorable neurologic outcome when BP targets above a threshold of SBP > 10th percentile for age and DBP > 50th percentile for age during the first 6 h post-arrest.

Clinical Instability Is a Sign of Severity of Illness: A Cohort Study.

OBJECTIVES: Test the hypothesis that within patient clinical instability measured by deterioration and improvement in mortality risk over 3-, 6-, 9-, and 12-hour time intervals is indicative of increasing severity of illness. DESIGN: Analysis of electronic health data from January 1, 2018, to February 29, 2020. SETTING: PICU and cardiac ICU at an academic children's hospital. PATIENTS: All PICU patients. Data included descriptive information, outcome, and independent variables used in the Criticality Index-Mortality. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 8,399 admissions with 312 deaths (3.7%). Mortality risk determined every three hours using the Criticality Index-Mortality, a machine learning algorithm calibrated to this hospital. Since the sample sizes were sufficiently large to expect statical differences, we also used two measures of effect size, the proportion of time deaths had greater instability than survivors, and the rank-biserial correlation, to assess the magnitude of the effect and complement our hypothesis tests. Within patient changes were compared for survivors and deaths. All comparisons of survivors versus deaths were less than 0.001. For all time intervals, two measures of effect size indicated that the differences between deaths and survivors were not clinically important. However, the within-patient maximum risk increase (clinical deterioration) and maximum risk decrease (clinical improvement) were both substantially greater in deaths than survivors for all time intervals. For deaths, the maximum risk increase ranged from 11.1% to 16.1% and the maximum decrease ranged from -7.3% to -10.0%, while the median maximum increases and decreases for survivors were all less than ± 0.1%. Both measures of effect size indicated moderate to high clinical importance. The within-patient volatility was greater than 4.5-fold greater in deaths than survivors during the first ICU day, plateauing at ICU days 4-5 at 2.5 greater volatility. CONCLUSIONS: Episodic clinical instability measured with mortality risk is a reliable sign of increasing severity of illness. Mortality risk changes during four time intervals demonstrated deaths have greater maximum and within-patient clinical instability than survivors. This observation confirms the clinical teaching that clinical instability is a sign of severity of illness.

The Association of the Lactate-Albumin Ratio With Mortality and Multiple Organ Dysfunction in PICU Patients.

OBJECTIVES: To compare the relative associations of lactate, albumin, and the lactate-albumin ratio (LAR) measured early in disease course against mortality and prevalence of multiple organ dysfunction syndrome (MODS) in a general sample of critically ill pediatric patients. DESIGN: Retrospective analysis of the Health Facts (Cerner Corporation, Kansas City, MO) national database. SETTING: U.S. hospitals with PICUs. PATIENTS: Children admitted to the ICU ( n = 648) from 2009 to 2018 who had lactate and albumin measured within 6 hours of admission. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 648 admissions were included, with an overall mortality rate of 10.8% ( n = 70) and a MODS prevalence of 29.3% ( n = 190). Compared with survivors, deaths had higher initial lactates (7.3 mmol/L [2.6-11.7 mmol/L] vs 1.9 mmol/L [1.2-3.1 mmol/L]; p < 0.01), lower initial albumins (3.3 g/dL [2.7-3.8 g/dL] vs 4.2 g/dL [3.7-4.7 g/dL]; p < 0.01), and higher LARs (2.2 [1.0-4.2] vs 0.5 [0.3-0.8]; p < 0.01), with similar trends in patients with MODS versus those without MODS. LAR demonstrated a higher odds ratio (OR) for death than initial lactate alone (2.34 [1.93-2.85] vs 1.29 [1.22-1.38]) and a higher OR for MODS than initial lactate alone (2.10 [1.73-2.56] vs 1.22 [1.16-1.29]). Area under the receiver operating characteristic (AUROC) curve of LAR for mortality was greater than initial lactate (0.86 vs 0.82; p < 0.01). The LAR AUROC for MODS was greater than the lactate AUROC (0.71 vs 0.66; p < 0.01). Trends of lactate, albumin, and LAR for mortality were consistent across several diagnostic subgroups (trauma, primary respiratory failure, toxicology), but not all. CONCLUSIONS: LAR measured early in the course of critical illness is significantly associated with mortality and development of MODS when compared with initial lactate or initial albumin alone in critically ill pediatric patients.

Acute Disorders of Consciousness in Pediatric Severe Sepsis and Organ Failure: Secondary Analysis of the Multicenter Phenotyping Sepsis-Induced Multiple Organ Failure Study.

OBJECTIVES: Acute disorders of consciousness (DoC) in pediatric severe sepsis are associated with increased risk of morbidity and mortality. We sought to examine the frequency of and factors associated with DoC in children with sepsis-induced organ failure. DESIGN: Secondary analysis of the multicenter Phenotyping Sepsis-Induced Multiple Organ Failure Study (PHENOMS). SETTING: Nine tertiary care PICUs in the United States. PATIENTS: Children less than 18 years old admitted to a PICU with severe sepsis and at least one organ failure during a PICU stay. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was frequency of DoC, defined as Glasgow Coma Scale (GCS) less than 12 in the absence of sedatives during an ICU stay, among children with severe sepsis and the following: single organ failure, nonphenotypeable multiple organ failure (MOF), MOF with one of the PHENOMS phenotypes (immunoparalysis-associated MOF [IPMOF], sequential liver failure-associated MOF, thrombocytopenia-associated MOF), or MOF with multiple phenotypes. A multivariable logistic regression analysis was performed to evaluate the association between clinical variables and organ failure groups with DoC. Of 401 children studied, 71 (18%) presented with DoC. Children presenting with DoC were older (median 8 vs 5 yr; p = 0.023), had increased hospital mortality (21% vs 10%; p = 0.011), and more frequently presented with both any MOF (93% vs 71%; p < 0.001) and macrophage activation syndrome (14% vs 4%; p = 0.004). Among children with any MOF, those presenting with DoC most frequently had nonphenotypeable MOF and IPMOF (52% and 34%, respectively). In the multivariable analysis, older age (odds ratio, 1.07; 95% CI, 1.01-1.12) and any MOF (3.22 [1.19-8.70]) were associated with DoC. CONCLUSIONS: One of every five children with severe sepsis and organ failure experienced acute DoC during their PICU stay. Preliminary findings suggest the need for prospective evaluation of DoC in children with sepsis and MOF.

Anticoagulation practices associated with bleeding and thrombosis in pediatric extracorporeal membrane oxygenation; a multi-center secondary analysis.

To determine associations between anticoagulation practices and bleeding and thrombosis during pediatric extracorporeal membrane oxygenation (ECMO), we performed a secondary analysis of prospectively collected data which included 481 children (<19 years), between January 2012 and September 2014. The primary outcome was bleeding or thrombotic events. Bleeding events included a blood product transfusion >80 ml/kg on any day, pulmonary hemorrhage, or intracranial bleeding, Thrombotic events included pulmonary emboli, intracranial clot, limb ischemia, cardiac clot, and arterial cannula or entire circuit change. Bleeding occurred in 42% of patients. Five percent of subjects thrombosed, of which 89% also bled. Daily bleeding odds were independently associated with day prior activated clotting time (ACT) (OR 1.03, 95% CI= 1.00, 1.05, p=0.047) and fibrinogen levels (OR 0.90, 95% CI 0.84, 0.96, p <0.001). Thrombosis odds decreased with increased day prior heparin dose (OR 0.88, 95% CI 0.81, 0.97, p=0.006). Lower ACT values and increased fibrinogen levels may be considered to decrease the odds of bleeding. Use of this single measure, however, may not be sufficient alone to guide optimal anticoagulation practice during ECMO.

Prevalence of Pathogenic and Potentially Pathogenic Inborn Error of Immunity Associated Variants in Children with Severe Sepsis.

PURPOSE: Our understanding of inborn errors of immunity is increasing; however, their contribution to pediatric sepsis is unknown. METHODS: We used whole-exome sequencing (WES) to characterize variants in genes related to monogenic immunologic disorders in 330 children admitted to intensive care for severe sepsis. We defined candidate variants as rare variants classified as pathogenic or potentially pathogenic in QIAGEN's Human Gene Mutation Database or novel null variants in a disease-consistent inheritance pattern. We investigated variant correlation with infection and inflammatory phenotype. RESULTS: More than one in two children overall and three of four African American children had immunodeficiency-associated variants. Children with variants had increased odds of isolating a blood or urinary pathogen (blood: OR 2.82, 95% CI: 1.12-7.10, p = 0.023, urine: OR: 8.23, 95% CI: 1.06-64.11, p = 0.016) and demonstrating increased inflammation with hyperferritinemia (ferritin [Formula: see text] ng/mL, OR: 2.16, 95% CI: 1.28-3.66, p = 0.004), lymphopenia (lymphocyte count < 1000/µL, OR: 1.66, 95% CI: 1.06 - 2.60, p = 0.027), thrombocytopenia (platelet count < 150,000/µL, OR: 1.76, 95% CI: 1.12-2.76, p = 0.013), and CRP greater than 10 mg/dl (OR: 1.71, 95% CI: 1.10-2.68, p = 0.017). They also had increased odds of requiring extracorporeal membrane oxygenation (ECMO, OR: 4.19, 95% CI: 1.21-14.5, p = 0.019). CONCLUSION: Herein, we describe the genetic findings in this severe pediatric sepsis cohort and their microbiologic and immunologic significance, providing evidence for the phenotypic effect of these variants and rationale for screening children with life-threatening infections for potential inborn errors of immunity.

Machine learning derivation of four computable 24-h pediatric sepsis phenotypes to facilitate enrollment in early personalized anti-inflammatory clinical trials.

BACKGROUND: Thrombotic microangiopathy-induced thrombocytopenia-associated multiple organ failure and hyperinflammatory macrophage activation syndrome are important causes of late pediatric sepsis mortality that are often missed or have delayed diagnosis. The National Institutes of General Medical Science sepsis research working group recommendations call for application of new research approaches in extant clinical data sets to improve efficiency of early trials of new sepsis therapies. Our objective is to apply machine learning approaches to derive computable 24-h sepsis phenotypes to facilitate personalized enrollment in early anti-inflammatory trials targeting these conditions. METHODS: We applied consensus, k-means clustering analysis to our extant PHENOtyping sepsis-induced Multiple organ failure Study (PHENOMS) dataset of 404 children. 24-hour computable phenotypes are derived using 25 available bedside variables including C-reactive protein and ferritin. RESULTS: Four computable phenotypes (PedSep-A, B, C, and D) are derived. Compared to all other phenotypes, PedSep-A patients (n = 135; 2% mortality) were younger and previously healthy, with the lowest C-reactive protein and ferritin levels, the highest lymphocyte and platelet counts, highest heart rate, and lowest creatinine (p < 0.05); PedSep-B patients (n = 102; 12% mortality) were most likely to be intubated and had the lowest Glasgow Coma Scale Score (p < 0.05); PedSep-C patients (n = 110; mortality 10%) had the highest temperature and Glasgow Coma Scale Score, least pulmonary failure, and lowest lymphocyte counts (p < 0.05); and PedSep-D patients (n = 56, 34% mortality) had the highest creatinine and number of organ failures, including renal, hepatic, and hematologic organ failure, with the lowest platelet counts (p < 0.05). PedSep-D had the highest likelihood of developing thrombocytopenia-associated multiple organ failure (Adj OR 47.51 95% CI [18.83-136.83], p < 0.0001) and macrophage activation syndrome (Adj OR 38.63 95% CI [13.26-137.75], p < 0.0001). CONCLUSIONS: Four computable phenotypes are derived, with PedSep-D being optimal for enrollment in early personalized anti-inflammatory trials targeting thrombocytopenia-associated multiple organ failure and macrophage activation syndrome in pediatric sepsis. A computer tool for identification of individual patient membership ( www.pedsepsis.pitt.edu ) is provided. Reproducibility will be assessed at completion of two ongoing pediatric sepsis studies.

Dynamic Mortality Risk Predictions for Children in ICUs: Development and Validation of Machine Learning Models.

OBJECTIVES: Assess a machine learning method of serially updated mortality risk. DESIGN: Retrospective analysis of a national database (Health Facts; Cerner Corporation, Kansas City, MO). SETTING: Hospitals caring for children in ICUs. PATIENTS: A total of 27,354 admissions cared for in ICUs from 2009 to 2018. INTERVENTIONS: None. MAIN OUTCOME: Hospital mortality risk estimates determined at 6-hour time periods during care in the ICU. Models were truncated at 180 hours due to decreased sample size secondary to discharges and deaths. MEASUREMENTS AND MAIN RESULTS: The Criticality Index, based on physiology, therapy, and care intensity, was computed for each admission for each time period and calibrated to hospital mortality risk (Criticality Index-Mortality [CI-M]) at each of 29 time periods (initial assessment: 6 hr; last assessment: 180 hr). Performance metrics and clinical validity were determined from the held-out test sample (n = 3,453, 13%). Discrimination assessed with the area under the receiver operating characteristic curve was 0.852 (95% CI, 0.843-0.861) overall and greater than or equal to 0.80 for all individual time periods. Calibration assessed by the Hosmer-Lemeshow goodness-of-fit test showed good fit overall (p = 0.196) and was statistically not significant for 28 of the 29 time periods. Calibration plots for all models revealed the intercept ranged from--0.002 to 0.009, the slope ranged from 0.867 to 1.415, and the R2 ranged from 0.862 to 0.989. Clinical validity assessed using population trajectories and changes in the risk status of admissions (clinical volatility) revealed clinical trajectories consistent with clinical expectations and greater clinical volatility in deaths than survivors (p < 0.001). CONCLUSIONS: Machine learning models incorporating physiology, therapy, and care intensity can track changes in hospital mortality risk during intensive care. The CI-M's framework and modeling method are potentially applicable to monitoring clinical improvement and deterioration in real time.

Strain Echocardiography and Myocardial Dysfunction in Critically Ill Children With Multisystem Inflammatory Syndrome Unrecognized by Conventional Echocardiography: A Retrospective Cohort Analysis.

OBJECTIVES: Multisystem inflammatory syndrome in children is a newly defined complication of severe acute respiratory syndrome coronavirus 2 infection that can result in cardiogenic shock in the pediatric population. Early detection of cardiac dysfunction is imperative in directing therapy and identifying patients at highest risk for deterioration. This study compares the strengths of conventional and strain echocardiography in identifying cardiac dysfunction in critically ill children with multisystem inflammatory syndrome in children and their association with ICU therapeutic needs and clinical outcomes. DESIGN: Retrospective, observational cohort study. SETTING: A large, quaternary care PICU. PATIENTS: Sixty-five pediatric patients admitted to the PICU with the diagnosis of multisystem inflammatory syndrome in children from March 2020 to March 2021. INTERVENTIONS: Global longitudinal strain four chamber was measured retrospectively by strain echocardiography and compared with conventional echocardiography. Cardiac dysfunction was defined by left ventricular ejection fraction less than 55% and global longitudinal strain four chamber greater than or equal to -17.2%. Clinical variables examined included cardiac biomarkers, immune therapies, and ICU interventions and outcomes. MEASUREMENTS AND MAIN RESULTS: Twenty-four patients (37%) had abnormal left ventricular ejection fraction and 56 (86%) had abnormal global longitudinal strain four chamber. Between patients with normal and abnormal left ventricular ejection fraction, we failed to identify a difference in cardiac biomarker levels, vasoactive use, respiratory support needs, or ICU length of stay. Global longitudinal strain four chamber was associated with maximum cardiac biomarker levels. Abnormal global longitudinal strain four chamber was associated with greater odds of any vasoactive use (odds ratio, 5.8; 95% CI, 1.3-25.3; z-statistic, 2.3; p = 0.021). The number of days of vasoactive infusion was correlated with global longitudinal strain four chamber (r = 0.400; 95% CI, 2.4-3.9; p < 0.001). Children with abnormal strain had longer ICU length of stay (4.5 d vs 2 d; p = 0.014). CONCLUSIONS: Our findings suggest strain echocardiography can detect abnormalities in cardiac function in multisystem inflammatory syndrome in children patients unrecognized by conventional echocardiography. These abnormalities are associated with increased use of intensive care therapies. Evaluation of these patients with strain echocardiography may better identify those with myocardial dysfunction and need for more intensive therapy.

Assessment of Patient Health-Related Quality of Life and Functional Outcomes in Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVES: To describe health-related quality of life (HRQL) and functional outcomes in pediatric acute respiratory distress syndrome (ARDS) and to determine risk factors associated with poor outcome defined as death or severe reduction in HRQL at 28 days or ICU discharge. DESIGN: Prospective multisite cohort-outcome study conducted between 2019 and 2020. SETTING: Eight academic PICUs in the United States. PATIENTS: Children with ARDS based on standard criteria. INTERVENTIONS: Patient characteristics and illness severity were collected during PICU admission. Parent proxy-report measurements were obtained at baseline, day 28/ICU discharge, month 3, and month 9, utilizing Pediatric Quality of Life Inventory and Functional Status Scale (FSS). A composite outcome evaluated using univariate and multivariate analysis was death or severe reduction in HRQL (>25% reduction in the Pediatric Quality of Life Inventory at day 28/ICU discharge. MEASUREMENTS AND MAIN RESULTS: This study enrolled 122 patients with a median age of 3 years (interquartile range, 1-12 yr). Common etiologies of ARDS included pneumonia ( n = 63; 52%) and sepsis ( n = 27; 22%). At day 28/ICU discharge, half (50/95; 53%) of surviving patients with follow-up data reported a greater than 10% decrease in HRQL from baseline, and approximately one-third of participants ( n = 19/61; 31%) reported a greater than 10% decrease in HRQL at 9 months. Trends in FSS were similar. Of 104 patients with data, 47 patients (45%) died or reported a severe decrease of greater than 25% in HRQL at day 28/ICU discharge. Older age was associated with an increased risk of death or severe reduction in HRQL (odds ratio, 1.08; CI, 1.01-1.16). CONCLUSIONS: Children with ARDS are at risk for deterioration in HRQL and FSS that persists up to 9 months after ARDS. Almost half of children with ARDS experience a poor outcome including death or severe reduction in HRQL at day 28/ICU discharge.