Transcriptomic profiles of multiple organ dysfunction syndrome phenotypes in pediatric critical influenza.

Background: Influenza virus is responsible for a large global burden of disease, especially in children. Multiple Organ Dysfunction Syndrome (MODS) is a life-threatening and fatal complication of severe influenza infection. Methods: We measured RNA expression of 469 biologically plausible candidate genes in children admitted to North American pediatric intensive care units with severe influenza virus infection with and without MODS. Whole blood samples from 191 influenza-infected children (median age 6.4 years, IQR: 2.2, 11) were collected a median of 27 hours following admission; for 45 children a second blood sample was collected approximately seven days later. Extracted RNA was hybridized to NanoString mRNA probes, counts normalized, and analyzed using linear models controlling for age and bacterial co-infections (FDR q<0.05). Results: Comparing pediatric samples collected near admission, children with Prolonged MODS for ≥7 days (n=38; 9 deaths) had significant upregulation of nine mRNA transcripts associated with neutrophil degranulation (RETN, TCN1, OLFM4, MMP8, LCN2, BPI, LTF, S100A12, GUSB) compared to those who recovered more rapidly from MODS (n=27). These neutrophil transcripts present in early samples predicted Prolonged MODS or death when compared to patients who recovered, however in paired longitudinal samples, they were not differentially expressed over time. Instead, five genes involved in protein metabolism and/or adaptive immunity signaling pathways (RPL3, MRPL3, HLA-DMB, EEF1G, CD8A) were associated with MODS recovery within a week. Conclusion: Thus, early increased expression of neutrophil degranulation genes indicated worse clinical outcomes in children with influenza infection, consistent with reports in adult cohorts with influenza, sepsis, and acute respiratory distress syndrome.

Dexmedetomidine for sedation during hematopoietic stem cell harvest apheresis and leukapheresis in the PICU: Guideline development.

BACKGROUND: Hematopoietic stem cell (HSC) harvest apheresis and leukapheresis are performed in the pediatric intensive care unit (PICU) for high-risk pediatric patients who require procedural sedation. Patients need central access either with their own central lines, ports or require apheresis catheter (CVL) placement. Previously, patients were either awake or emerging from sedation on PICU admission. Uncertainty regarding procedural sedation plans caused delays initiating sedation and apheresis. A guideline was developed to standardize Dexmedetomidine (DEX) for procedural sedation. We investigated if guideline implementation would improve efficiency during PICU admission as demonstrated by shorter time intervals for initiation of sedation, apheresis, PICU length of stay and less alternative sedating medication. METHODS: Data was collected retrospectively from electronic health records of preguideline and post-guideline patients who were admitted to the PICU for sedated apheresis. We compared demographic and clinical characteristics, time intervals for sedation, apheresis, PICU length of stay, and sedation agents between the two groups using Fisher Exact tests and Mann-Whitney tests, as appropriate. RESULTS: The groups did not differ in age or weight at the time of apheresis. All intervals of time compared were shorter post-guideline. Time intervals from admission to start of sedation, admission to start of apheresis, and admission to end of apheresis were statistically significantly different. The type and number of alternative sedating medications administered did not differ between the two groups. CONCLUSION: This guideline implementation improved efficiency during PICU admission. This study might have been too small to demonstrate statistically significant differences in other time intervals studied.

Development of a Standardized Clinical Assessment and Management Plan for Pediatric Acute Respiratory Distress Syndrome.

Pediatric acute respiratory distress syndrome (PARDS) is one of the most challenging patient populations for a clinician to manage with mortality between 8 and 31%. The project was designed to identify patients with PARDS, implement management guidelines with the goal of standardizing practice. Our objectives were to describe the development and implementation of a protocolized approach to identify patients with PARDS and institute ventilator management guidelines. Patients who met criteria for moderate or severe PARDS as per the Pediatric Acute Lung Injury Consensus Conference (PALICC) definitions were identified using the best practice alert (BPA) in the electronic health record (EHR). Patients who did not meet exclusion criteria qualified for management using the Standardized Clinical Assessment and Management Plan (SCAMP), a quality improvement (QI) methodology with iterative cycles. The creation of a BPA enabled identification of patients with PARDS. With our second cycle, the number of false BPA alerts due to incorrect data decreased from 66.7 (68/102) to 29.2% (19/65; p < 0.001) and enrollment increased from 48.3 (14/29) to 73.2% (30/41; p = 0.03). Evaluation of our statistical process control chart (SPC) demonstrated a shift in the adherence with the tidal volume guideline. Overall, we found that SCAMP methodology, when used in the development of institutional PARDS management guidelines, allows for development of a process to aid identification of patients and monitor adherence to management guidelines. This should eventually allow assessment of impact of deviations from clinical practice guidelines.

Epidemiology and Outcomes of Critically Ill Children at Risk for Pediatric Acute Respiratory Distress Syndrome: A Pediatric Acute Respiratory Distress Syndrome Incidence and Epidemiology Study.

OBJECTIVES: Interventional trials aimed at pediatric acute respiratory distress syndrome prevention require accurate identification of high-risk patients. In this study, we aimed to characterize the frequency and outcomes of children meeting "at risk for pediatric acute respiratory distress syndrome" criteria as defined by the Pediatric Acute Lung Injury Consensus Conference. DESIGN: Planned substudy of the prospective multicenter, international Pediatric Acute Respiratory Distress Syndrome Incidence and Epidemiology study conducted during 10 nonconsecutive weeks (May 2016-June 2017). SETTING: Thirty-seven international PICUs. PATIENTS: Three-hundred ten critically ill children meeting Pediatric Acute Lung Injury Consensus Conference "at-risk for pediatric acute respiratory distress syndrome" criteria. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We evaluated the frequency of children at risk for pediatric acute respiratory distress syndrome and rate of subsequent pediatric acute respiratory distress syndrome diagnosis and used multivariable logistic regression to identify factors associated with subsequent pediatric acute respiratory distress syndrome. Frequency of at risk for pediatric acute respiratory distress syndrome was 3.8% (95% CI, 3.4-5.2%) among the 8,122 critically ill children who were screened and 5.8% (95% CI, 5.2-6.4%) among the 5,334 screened children on positive pressure ventilation or high-flow oxygen. Among the 310 at-risk children, median age was 2.1 years (interquartile range, 0.5-7.3 yr). Sixty-six children (21.3%) were subsequently diagnosed with pediatric acute respiratory distress syndrome, a median of 22.6 hours (interquartile range, 9.8-41.0 hr) later. Subsequent pediatric acute respiratory distress syndrome was associated with increased mortality (21.2% vs 3.3%; p < 0.001) and longer durations of invasive ventilation and PICU care. Subsequent pediatric acute respiratory distress syndrome rate did not differ by respiratory support modality at the time of meeting at risk criteria but was independently associated with lower initial saturation:Fio2 ratio, progressive tachycardia, and early diuretic administration. CONCLUSIONS: The Pediatric Acute Lung Injury Consensus Conference "at-risk for pediatric acute respiratory distress syndrome" criteria identify critically ill children at high risk of pediatric acute respiratory distress syndrome and poor outcomes. Interventional trials aimed at pediatric acute respiratory distress syndrome prevention should target patients early in their illness course and include patients on high-flow oxygen and positive pressure ventilation.

Adherence to Lung-Protective Ventilation Principles in Pediatric Acute Respiratory Distress Syndrome: A Pediatric Acute Respiratory Distress Syndrome Incidence and Epidemiology Study.

OBJECTIVES: To describe mechanical ventilation management and factors associated with nonadherence to lung-protective ventilation principles in pediatric acute respiratory distress syndrome. DESIGN: A planned ancillary study to a prospective international observational study. Mechanical ventilation management (every 6 hr measurements) during pediatric acute respiratory distress syndrome days 0-3 was described and compared with Pediatric Acute Lung Injury Consensus Conference tidal volume recommendations (< 7 mL/kg in children with impaired respiratory system compliance, < 9 mL/kg in all other children) and the Acute Respiratory Distress Syndrome Network lower positive end-expiratory pressure/higher Fio2 grid recommendations. SETTING: Seventy-one international PICUs. PATIENTS: Children with pediatric acute respiratory distress syndrome. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Analyses included 422 children. On pediatric acute respiratory distress syndrome day 0, median tidal volume was 7.6 mL/kg (interquartile range, 6.3-8.9 mL/kg) and did not differ by pediatric acute respiratory distress syndrome severity. Plateau pressure was not recorded in 97% of measurements. Using delta pressure (peak inspiratory pressure - positive end-expiratory pressure), median tidal volume increased over quartiles of median delta pressure (p = 0.007). Median delta pressure was greater than or equal to 18 cm H2O for all pediatric acute respiratory distress syndrome severity levels. In severe pediatric acute respiratory distress syndrome, tidal volume was greater than or equal to 7 mL/kg 62% of the time, and positive end-expiratory pressure was lower than recommended by the positive end-expiratory pressure/Fio2 grid 70% of the time. In multivariable analysis, tidal volume nonadherence was more common with severe pediatric acute respiratory distress syndrome, fewer PICU admissions/yr, non-European PICUs, higher delta pressure, corticosteroid use, and pressure control mode. Adherence was associated with underweight stature and cuffed endotracheal tubes. In multivariable analysis, positive end-expiratory pressure/Fio2 grid nonadherence was more common with higher pediatric acute respiratory distress syndrome severity, ventilator decisions made primarily by the attending physician, pre-ICU cardiopulmonary resuscitation, underweight stature, and age less than 2 years. Adherence was associated with respiratory therapist involvement in ventilator management and longer time from pediatric acute respiratory distress syndrome diagnosis. Higher nonadherence to tidal volume and positive end-expiratory pressure recommendations were independently associated with higher mortality and longer duration of ventilation after adjustment for confounding variables. In stratified analyses, these associations were primarily influenced by children with severe pediatric acute respiratory distress syndrome. CONCLUSIONS: Nonadherence to lung-protective ventilation principles is common in pediatric acute respiratory distress syndrome and may impact outcome. Modifiable factors exist that may improve adherence.

The Impact of Preintubation Noninvasive Ventilation on Outcomes in Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVES: There is evidence that noninvasive ventilation decreases the need for invasive mechanical ventilation. However, children with pediatric acute respiratory distress syndrome who fail noninvasive ventilation may have worse outcomes than those who are intubated without exposure to noninvasive ventilation. Our objective was to evaluate the impact of preintubation noninvasive ventilation on children with pediatric acute respiratory distress syndrome. DESIGN: Secondary analysis of data from the Randomized Evaluation of Sedation Titration for Respiratory Failure trial. SETTING: Thirty-one PICUs in the United States. PATIENTS: Children 2 weeks to 17 years old with pediatric acute respiratory distress syndrome receiving invasive mechanical ventilation, excluding those admitted with tracheostomies. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 2,427 subjects receiving invasive mechanical ventilation, preintubation noninvasive ventilation was used in 995 (41%). Compared with subjects without preintubation noninvasive ventilation use, subjects with preintubation noninvasive ventilation use were more likely to have a history of seizures (10% vs 8%; p = 0.04) or cancer (11% vs 6%; p < 0.001) and have moderate or severe pediatric acute respiratory distress syndrome by the end of their first full day of invasive mechanical ventilation (68% vs 60%; p < 0.001). Adjusting for age, severity of illness on PICU admission, and baseline functional status, preintubation noninvasive ventilation use resulted in longer invasive mechanical ventilation duration (median 7.0 vs 6.0 d), longer PICU (10.8 vs 8.9 d), and hospital (17 vs 14 d) lengths of stay, and higher 28-day (5% vs 4%) and 90-day (8% vs 5%) inhospital mortalities (all comparisons p < 0.001). Longer duration of noninvasive ventilation before intubation was associated with worse outcomes. CONCLUSIONS: In children with pediatric acute respiratory distress syndrome, preintubation noninvasive ventilation use is associated with worse outcomes when compared with no preintubation noninvasive ventilation use. These data can be used to inform the design of clinical studies to evaluate best noninvasive ventilation practices in children with pediatric acute respiratory distress syndrome.

Correction to: Methods in the design and implementation of the Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE) clinical trial.

AbstractFollowing publication of the original article [1], the authors notified us of a typing error in spelling Dr. Asario's name. The original publication has been corrected.

Vancomycin Monotherapy May Be Insufficient to Treat Methicillin-resistant Staphylococcus aureus Coinfection in Children With Influenza-related Critical Illness.

Background: Coinfection with influenza virus and methicillin-resistant Staphylococcus aureus (MRSA) causes life-threatening necrotizing pneumonia in children. Sporadic incidence precludes evaluation of antimicrobial efficacy. We assessed the clinical characteristics and outcomes of critically ill children with influenza-MRSA pneumonia and evaluated antibiotic use. Methods: We enrolled children (<18 years) with influenza infection and respiratory failure across 34 pediatric intensive care units 11/2008-5/2016. We compared baseline characteristics, clinical courses, and therapies in children with MRSA coinfection, non-MRSA bacterial coinfection, and no bacterial coinfection. Results: We enrolled 170 children (127 influenza A, 43 influenza B). Children with influenza-MRSA pneumonia (N = 30, 87% previously healthy) were older than those with non-MRSA (N = 61) or no (N = 79) bacterial coinfections. Influenza-MRSA was associated with increased leukopenia, acute lung injury, vasopressor use, extracorporeal life support, and mortality than either group (P ≤ .0001). Influenza-related mortality was 40% with MRSA compared to 4.3% without (relative risk [RR], 9.3; 95% confidence interval [CI], 3.8-22.9). Of 29/30 children with MRSA who received vancomycin within the first 24 hours of hospitalization, mortality was 12.5% (N = 2/16) if treatment also included a second anti-MRSA antibiotic compared to 69.2% (N = 9/13) with vancomycin monotherapy (RR, 5.5; 95% CI, 1.4, 21.3; P = .003). Vancomycin dosing did not influence initial trough levels; 78% were <10 µg/mL. Conclusions: Influenza-MRSA coinfection is associated with high fatality in critically ill children. These data support early addition of a second anti-MRSA antibiotic to vancomycin in suspected severe cases.

Methods in the design and implementation of the Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE) clinical trial.

BACKGROUND: Few papers discuss the pragmatics of conducting large, cluster randomized clinical trials. Here we describe the sequential steps taken to develop methods to implement the Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE) trial that tested the effect of a nurse-implemented, goal-directed, comfort algorithm on clinical outcomes in pediatric patients with acute respiratory failure. METHODS: After development in a single institution, the RESTORE intervention was pilot-tested in two pediatric intensive care units (PICUs) to evaluate safety and feasibility. After the pilot, the RESTORE intervention was simplified to enhance reproducibility across multiple PICUs. The final RESTORE trial was developed as a cluster randomized clinical trial where the unit of randomization was the PICU, stratified by PICU size, and the unit of inference was the patient. Study execution was revised based on our Data and Safety Monitoring Board's recommendation to consult with the Department of Health and Human Services' Office of Human Research Protection (OHRP) on how best to consent eligible subjects. OHRP deemed that the RESTORE intervention posed greater than minimal risk and that all enrolled subjects provide consent reflecting their level of participation. RESULTS: Thirty-one PICUs of varying size, organization and academic affiliation participated and over 2800 critically ill infants and children supported on mechanical ventilation for acute pulmonary disease were enrolled. The primary outcome for the trial was the duration of mechanical ventilation; secondary outcomes included time awake and comfortable, total sedative exposure and iatrogenic withdrawal symptoms. Throughout the clinical trial the investigative team worked to maintain treatment fidelity, enrollment milestones and co-investigator enthusiasm. We considered the potential impact of competing clinical trials through a decision-making framework. CONCLUSIONS: The RESTORE clinical trial was a large and complex multicenter study that has provided the necessary evidence to guide sedation practices in the field of pediatric critical care. Specific issues that were unique to this trial included level of consent, adding clinical sites to augment enrollment and evaluating the potential impact of competing clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov , Identifiers: Pilot trial: NCT00142766 ; Retrospectively registerd on 2 September 2005. Cluster randomized trial: NCT00814099 . Registered on 23 December 2008.

Hyperchloremia Is Associated With Complicated Course and Mortality in Pediatric Patients With Septic Shock.

OBJECTIVE: Hyperchloremia is associated with poor outcome among critically ill adults, but it is unknown if a similar association exists among critically ill children. We determined if hyperchloremia is associated with poor outcomes in children with septic shock. DESIGN: Retrospective analysis of a pediatric septic shock database. SETTING: Twenty-nine PICUs in the United States. PATIENTS: Eight hundred ninety children 10 years and younger with septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We considered the minimum, maximum, and mean chloride values during the initial 7 days of septic shock for each study subject as separate hyperchloremia variables. Within each category, we considered hyperchloremia as a dichotomous variable defined as a serum concentration greater than or equal to 110 mmol/L. We used multivariable logistic regression to determine the association between the hyperchloremia variables and outcome, adjusted for illness severity. We considered all cause 28-day mortality and complicated course as the primary outcome variables. Complicated course was defined as mortality by 28 days or persistence of greater than or equal to two organ failures at day 7 of septic shock. Secondarily, we conducted a stratified analysis using a biomarker-based mortality risk stratification tool. There were 226 patients (25%) with a complicated course and 93 mortalities (10%). Seventy patients had a minimum chloride greater than or equal to 110 mmol/L, 179 had a mean chloride greater than or equal to 110 mmol/L, and 514 had a maximum chloride greater than or equal to 110 mmol/L. A minimum chloride greater than or equal to 110 mmol/L was associated with increased odds of complicated course (odds ratio, 1.9; 95% CI, 1.1-3.2; p = 0.023) and mortality (odds ratio, 3.7; 95% CI, 2.0-6.8; p < 0.001). A mean chloride greater than or equal to 110 mmol/L was also associated with increased odds of mortality (odds ratio, 2.1; 95% CI, 1.3-3.5; p = 0.002). The secondary analysis yielded similar results. CONCLUSION: Hyperchloremia is independently associated with poor outcomes among children with septic shock.

Endotype Transitions During the Acute Phase of Pediatric Septic Shock Reflect Changing Risk and Treatment Response.

OBJECTIVE: We previously identified septic shock endotypes A and B based on 100 genes reflecting adaptive immunity and glucocorticoid receptor signaling. The endotypes differ with respect to outcome and corticosteroid responsiveness. We determined whether endotypes change during the initial 3 days of illness, and whether changes are associated with outcomes. DESIGN: Observational cohort study including existing and newly enrolled participants. SETTING: Multiple PICUs. PATIENTS: Children with septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We measured the 100 endotyping genes at day 1 and day 3 of illness in 375 patients. We determined if endotype assignment changes over time, and whether changing endotype is associated with corticosteroid response and outcomes. We used multivariable logistic regression to adjust for illness severity, age, and comorbidity burden. Among the 132 subjects assigned to endotype A on day 1, 56 (42%) transitioned to endotype B by day 3. Among 243 subjects assigned to endotype B on day 1, 77 (32%) transitioned to endotype A by day 3. Assignment to endotype A on day 1 was associated with increased odds of mortality. This risk was modified by the subsequent day 3 endotype assignment. Corticosteroids were associated with increased risk of mortality among subjects who persisted as endotype A. CONCLUSIONS: A substantial proportion of children with septic shock transition endotypes during the acute phase of illness. The risk of poor outcome and the response to corticosteroids change with changes in endotype assignment. Patients persisting as endotype A are at highest risk of poor outcomes.

Improved Risk Stratification in Pediatric Septic Shock Using Both Protein and mRNA Biomarkers. PERSEVERE-XP.

RATIONALE: We previously derived and validated the Pediatric Sepsis Biomarker Risk Model (PERSEVERE) to estimate baseline mortality risk in children with septic shock. The PERSEVERE biomarkers are serum proteins selected from among the proteins directly related to 80 mortality risk assessment genes. The initial approach to selecting the PERSEVERE biomarkers left 68 genes unconsidered. OBJECTIVES: To determine if the 68 previously unconsidered genes can improve upon the performance of PERSEVERE and to provide biological information regarding the pathophysiology of septic shock. METHODS: We reduced the number of variables by determining the biological linkage of the 68 previously unconsidered genes. The genes identified through variable reduction were combined with the PERSEVERE-based mortality probability to derive a risk stratification model for 28-day mortality using classification and regression tree methodology (n = 307). The derived tree, PERSEVERE-XP, was then tested in a separate cohort (n = 77). MEASUREMENTS AND MAIN RESULTS: Variable reduction revealed a network consisting of 18 mortality risk assessment genes related to tumor protein 53 (TP53). In the derivation cohort, PERSEVERE-XP had an area under the receiver operating characteristic curve (AUC) of 0.90 (95% confidence interval, 0.85-0.95) for differentiating between survivors and nonsurvivors. In the test cohort, the AUC was 0.96 (95% confidence interval, 0.91-1.0). The AUC of PERSEVERE-XP was superior to that of PERSEVERE. CONCLUSIONS: PERSEVERE-XP combines protein and mRNA biomarkers to provide mortality risk stratification with possible clinical utility. PERSEVERE-XP significantly improves on PERSEVERE and suggests a role for TP53-related cellular division, repair, and metabolism in the pathophysiology of septic shock.

Glucocorticoid Receptor Polymorphisms and Outcomes in Pediatric Septic Shock.

OBJECTIVE: Polymorphisms of the glucocorticoid receptor gene are associated with outcome and corticosteroid responsiveness among patients with inflammatory disorders. We conducted a candidate gene association study to test the hypothesis that these polymorphisms are associated with outcome and corticosteroid responsiveness among children with septic shock. DESIGN: We genotyped 482 children with septic shock for the presence of two glucocorticoid receptor polymorphisms (rs56149945 and rs41423247) associated with increased sensitivity and one glucocorticoid receptor polymorphism (rs6198) associated with decreased sensitivity to corticosteroids. The primary outcome variable was complicated course, defined as 28-day mortality or the persistence of two or more organ failures 7 days after a septic shock diagnosis. We used logistic regression to test for an association between corticosteroid exposure and outcome, within genotype group, and adjusted for illness severity. SETTING: Multiple PICUs in the United States. INTERVENTIONS: Standard care. MEASUREMENTS AND MAIN RESULTS: There were no differences in outcome when comparing the various genotype groups. Among patients homozygous for the wild-type glucocorticoid receptor allele, corticosteroids were independently associated with increased odds of complicated course (odds ratio, 2.30; 95% CI, 1.01-5.21; p = 0.047). CONCLUSIONS: Based on these glucocorticoid receptor polymorphisms, we could not detect a beneficial effect of corticosteroids among any genotype group. Among children homozygous for the wild-type allele, corticosteroids were independently associated with increased odds of poor outcome.

Accuracy of an Extubation Readiness Test in Predicting Successful Extubation in Children With Acute Respiratory Failure From Lower Respiratory Tract Disease.

OBJECTIVE: Identifying children ready for extubation is desirable to minimize morbidity and mortality associated with prolonged mechanical ventilation and extubation failure. We determined the accuracy of an extubation readiness test (Randomized Evaluation of Sedation Titration for Respiratory Failure extubation readiness test) in predicting successful extubation in children with acute respiratory failure from lower respiratory tract disease. DESIGN: Secondary analysis of data from the Randomized Evaluation of Sedation Titration for Respiratory Failure clinical trial, a pediatric multicenter cluster randomized trial of sedation. SETTING: Seventeen PICUs in the intervention arm. PATIENTS: Children 2 weeks to 17 years receiving invasive mechanical ventilation for lower respiratory tract disease. INTERVENTION: Extubation readiness test in which spontaneously breathing children with oxygenation index less than or equal to 6 were placed on FIO2 of 0.50, positive end-expiratory pressure of 5 cm H2O, and pressure support. MEASUREMENTS AND MAIN RESULTS: Of 1,042 children, 444 (43%) passed their first extubation readiness test. Of these, 295 (66%) were extubated within 10 hours of starting the extubation readiness test, including 272 who were successfully extubated, for a positive predictive value of 92%. Among 861 children who were extubated for the first time within 10 hours of performing an extubation readiness test, 788 passed their extubation readiness test and 736 were successfully extubated for a positive predictive value of 93%. The median time of day for extubation with an extubation readiness test was 12:15 hours compared with 14:54 hours for extubation without an extubation readiness test within 10 hours (p < 0.001). CONCLUSIONS: In children with acute respiratory failure from lower respiratory tract disease, an extubation readiness test, as described, should be considered at least daily if the oxygenation index is less than or equal to 6. If the child passes the extubation readiness test, there is a high likelihood of successful extubation.

Pediatric Ventilator-Associated Infections: The Ventilator-Associated INfection Study.

OBJECTIVE: Suspected ventilator-associated infection is the most common reason for antibiotics in the PICU. We sought to characterize the clinical variables associated with continuing antibiotics after initial evaluation for suspected ventilator-associated infection and to determine whether clinical variables or antibiotic treatment influenced outcomes. DESIGN: Prospective, observational cohort study conducted in 47 PICUs in the United States, Canada, and Australia. Two hundred twenty-nine pediatric patients ventilated more than 48 hours undergoing respiratory secretion cultures were enrolled as "suspected ventilator-associated infection" in a prospective cohort study, those receiving antibiotics of less than or equal to 3 days were categorized as "evaluation only," and greater than 3 days as "treated." Demographics, diagnoses, comorbidities, culture results, and clinical data were compared between evaluation only and treated subjects and between subjects with positive versus negative cultures. SETTING: PICUs in 47 hospitals in the United States, Canada, and Australia. SUBJECTS: All patients undergoing respiratory secretion cultures during the 6 study periods. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Treated subjects differed from evaluation-only subjects only in frequency of positive cultures (79% vs 36%; p < 0.0001). Subjects with positive cultures were more likely to have chronic lung disease, tracheostomy, and shorter PICU stay, but there were no differences in ventilator days or mortality. Outcomes were similar in subjects with positive or negative cultures irrespective of antibiotic treatment. Immunocompromise and higher Pediatric Logistic Organ Dysfunction scores were the only variables associated with mortality in the overall population, but treated subjects with endotracheal tubes had significantly lower mortality. CONCLUSIONS: Positive respiratory cultures were the primary determinant of continued antibiotic treatment in children with suspected ventilator-associated infection. Positive cultures were not associated with worse outcomes irrespective of antibiotic treatment although the lower mortality in treated subjects with endotracheal tubes is notable. The necessity of continuing antibiotics for a positive respiratory culture in suspected ventilator-associated infection requires further study.

Pediatric Sepsis Biomarker Risk Model-II: Redefining the Pediatric Sepsis Biomarker Risk Model With Septic Shock Phenotype.

OBJECTIVE: The Pediatric Sepsis Biomarker Risk Model (PERSEVERE), a pediatric sepsis risk model, uses biomarkers to estimate baseline mortality risk for pediatric septic shock. It is unknown how PERSEVERE performs within distinct septic shock phenotypes. We tested PERSEVERE in children with septic shock and thrombocytopenia-associated multiple organ failure (TAMOF), and in those without new onset thrombocytopenia but with multiple organ failure (MOF). DESIGN: PERSEVERE-based mortality risk was generated for each study subject (n = 660). A priori, we determined that if PERSEVERE did not perform well in both the TAMOF and the MOF cohorts, we would revise PERSEVERE to incorporate admission platelet counts. SETTING: Multiple PICUs in the United States. INTERVENTIONS: Standard care. MEASUREMENTS AND MAIN RESULTS: PERSEVERE performed well in the TAMOF cohort (areas under the receiver operating characteristic curves [AUC], 0.84 [95% CI, 0.77-0.90]), but less well in the MOF cohort (AUC, 0.71 [0.61-0.80]). PERSEVERE was revised using 424 subjects previously reported in the derivation phase. PERSEVERE-II had an AUC of 0.89 (0.85-0.93) and performed equally well across TAMOF and MOF cohorts. PERSEVERE-II performed well when tested in 236 newly enrolled subjects. Sample size calculations for a clinical trial testing the efficacy of plasma exchange for children with septic shock and TAMOF indicated PERSEVERE-II-based stratification could substantially reduce the number of patients necessary, when compared with no stratification. CONCLUSIONS: Testing PERSEVERE in the context of septic shock phenotypes prompted a revision incorporating platelet count. PERSEVERE-II performs well upon testing, independent of TAMOF or MOF status. PERSEVERE-II could potentially serve as a prognostic enrichment tool.