Early Use of Adjunctive Therapies for Pediatric Acute Respiratory Distress Syndrome:A PARDIE Study

Rationale: Few data exist to guide early adjunctive therapy use in pediatric acute respiratory distress syndrome (PARDS). Objectives: To describe contemporary use of adjunctive therapies for early PARDS as a framework for future investigations. Methods: This was a preplanned substudy of a prospective, international, cross-sectional observational study of children with PARDS from 100 centers over 10 study weeks. Measurements and Main Results: We investigated six adjunctive therapies for PARDS: continuous neuromuscular blockade, corticosteroids, inhaled nitric oxide (iNO), prone positioning, high-frequency oscillatory ventilation (HFOV), and extracorporeal membrane oxygenation. Almost half (45%) of children with PARDS received at least one therapy. Variability was noted in the median starting oxygenation index of each therapy; corticosteroids started at the lowest oxygenation index (13.0; interquartile range, 7.6–22.0) and HFOV at the highest (25.7; interquartile range, 16.7–37.3). Continuous neuromuscular blockade was the most common, used in 31%, followed by iNO (13%), corticosteroids (10%), prone positioning (10%), HFOV (9%), and extracorporeal membrane oxygenation (3%). Steroids, iNO, and HFOV were associated with comorbidities. Prone positioning and HFOV were more common in middle-income countries and less frequently used in North America. The use of multiple ancillary therapies increased over the first 3 days of PARDS, but there was not an easily identifiable pattern of combination or order of use. Conclusions: The contemporary description of prevalence, combinations of therapies, and oxygenation threshold for which the therapies are applied is important for design of future studies. Region of the world, income, and comorbidities influence adjunctive therapy use and are important variables to include in PARDS investigations

Severe Acute Kidney Injury is Associated with Increased Risk of Death and New Morbidity After Pediatric Septic Shock

Objectives: Acute kidney injury is common in critically ill children; however, the frequency of septic shock-associated acute kidney injury and impact on functional status are unknown. We evaluated functional outcomes of children with septic shock-associated acute kidney injury. Design: Secondary analysis of patients with septic shock from the prospective Life after Pediatric Sepsis Evaluation study. We defined acute kidney injury using Kidney Disease Improving Global Outcomes criteria, comparing patients with absent/Stage 1 acute kidney injury to those with Stage 2/3 acute kidney injury (severe acute kidney injury). Our primary outcome was a composite of mortality or new functional morbidity at day 28 of hospitalization or discharge. We also assessed poor long-term outcome, defined as mortality or a persistent, serious deterioration in health-related quality of life at 3 months. Setting: Twelve academic PICUs in the United States. Patients: Critically ill children, 1 month to 18 years, with community-acquired septic shock requiring vasoactive-inotropic support. Interventions: None. Measurements and main results: More than 50% of patients (176/348) developed severe acute kidney injury; of those, 21.6% (38/176) required renal replacement therapy. Twice as many patients with severe acute kidney injury died or developed new substantive functional morbidity (38.6 vs 16.3%; p < 0.001). After adjustment for age, malignancy, and initial illness severity, severe acute kidney injury was independently associated with mortality or new substantive morbidity (adjusted odds ratio, 2.78; 95% CI, 1.63-4.81; p < 0.001). Children with severe acute kidney injury had poorer health-related quality of life at 3 months (adjusted effect size 2.46; 95% CI, 1.44-4.20; p = 0.002). Children with severe acute kidney injury required longer duration of mechanical ventilation (11.0 vs 7.0 d; p < 0.001) and PICU stay (11.7 vs 7.1 d; p < 0.001). Conclusions: Among children with septic shock, severe acute kidney injury was independently associated with increased risk of death or new substantive functional morbidity. Survivors of sepsis with severe acute kidney injury were more likely to have persistent, serious health-related quality of life deterioration at 3 months

Predicting Mortality in Children With Pediatric Acute Respiratory Distress Syndrome:A Pediatric Acute Respiratory Distress Syndrome Incidence and Epidemiology Study

OBJECTIVES: Pediatric acute respiratory distress syndrome is heterogeneous, with a paucity of risk stratification tools to assist with trial design. We aimed to develop and validate mortality prediction models for patients with pediatric acute respiratory distress syndrome. DESIGN: Leveraging additional data collection from a preplanned ancillary study (Version 1) of the multinational Pediatric Acute Respiratory Distress syndrome Incidence and Epidemiology study, we identified predictors of mortality. Separate models were built for the entire Version 1 cohort, for the cohort excluding neurologic deaths, for intubated subjects, and for intubated subjects excluding neurologic deaths. Models were externally validated in a cohort of intubated pediatric acute respiratory distress syndrome patients from the Children's Hospital of Philadelphia. SETTING: The derivation cohort represented 100 centers worldwide; the validation cohort was from Children's Hospital of Philadelphia. PATIENTS: There were 624 and 640 subjects in the derivation and validation cohorts, respectively. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The model for the full cohort included immunocompromised status, Pediatric Logistic Organ Dysfunction 2 score, day 0 vasopressor-inotrope score and fluid balance, and PaO2/FIO2 6 hours after pediatric acute respiratory distress syndrome onset. This model had good discrimination (area under the receiver operating characteristic curve 0.82), calibration, and internal validation. Models excluding neurologic deaths, for intubated subjects, and for intubated subjects excluding neurologic deaths also demonstrated good discrimination (all area under the receiver operating characteristic curve ≥ 0.84) and calibration. In the validation cohort, models for intubated pediatric acute respiratory distress syndrome (including and excluding neurologic deaths) had excellent discrimination (both area under the receiver operating characteristic curve ≥ 0.85), but poor calibration. After revision, the model for all intubated subjects remained miscalibrated, whereas the model excluding neurologic deaths showed perfect calibration. Mortality models also stratified ventilator-free days at 28 days in both derivation and validation cohorts. CONCLUSIONS: We describe predictive models for mortality in pediatric acute respiratory distress syndrome using readily available variables from day 0 of pediatric acute respiratory distress syndrome which outperform severity of illness scores and which demonstrate utility for composite outcomes such as ventilator-free days. Models can assist with risk stratification for clinical trials

Pulmonary Arterial Hypertension in Pediatric Patients with Hematopoietic Stem Cell Transplant–Associated Thrombotic Microangiopathy

AbstractPulmonary arterial hypertension (PAH) is rarely included in the differential diagnosis of cardiorespiratory failure after pediatric hematopoietic stem cell transplant (HSCT) as the clinical presentation is nonspecific and may mimic other etiologies. The pathogenesis of PAH in HSCT is poorly understood and the diagnosis requires a high degree of suspicion. We describe 5 children diagnosed with PAH after allogeneic HSCT. All 5 patients had prolonged clinical signs of transplantation-associated thrombotic microangiopathy (TA-TMA) when they presented with hypoxemic respiratory failure and evidence of PAH. Four of the 5 patients had echocardiographic evidence of PAH, and 1 patient was diagnosed with PAH only on autopsy. PAH was diagnosed a median of 76 days (range, 56-101 days) after a diagnosis of TA-TMA. Despite aggressive medical management, including inhaled nitric oxide, 4 of the 5 patients died. One patient recovered from PAH after 11 months of sildenafil therapy. Three of the 4 deceased patients had an autopsy performed, demonstrating severe pulmonary vascular disease consistent with TA-TMA and severe PAH. We conclude that TA-TMA can be associated with significant pulmonary vascular injury presenting as hypoxemic respiratory failure with PAH after HSCT. Pediatric patients with unexplained hypoxemia after HSCT should be evaluated for both transplantation complications, TA-TMA and PAH, accordingly

C-peptide ameliorates kidney injury following hemorrhagic shock

Reperfusion injury following hemorrhagic shock is accompanied by the development of a systemic inflammatory state that may lead to organ failure. C-peptide has been shown to exert anti-inflammatory effects in sepsis and myocardial ischemia-reperfusion injury, and to ameliorate renal dysfunction in diabetic animals. Hence, we investigated the effect of C-peptide on kidney injury following hemorrhagic shock. We hypothesized that C-peptide would exert reno-protective effects by blunting inflammation. Hemorrhagic shock was induced in male rats (3–4 months old) by withdrawing blood from the femoral artery to a mean arterial pressure of 50 mmHg. Animals were kept in shock for 3h at which time they were rapidly resuscitated by returning their shed blood. At the time of resuscitation and every hour thereafter, one group of animals received C-peptide (280 nmol/kg intravenously) while another group received vehicle. Hemorrhagic shock resulted in significant rise in plasma levels of creatinine and elevated kidney neutrophil infiltration as evaluated by myeloperoxidase (MPO) activity in vehicle-treated rats in comparison with sham rats, thus suggesting kidney injury. Treatment with C-peptide significantly attenuated the rise in creatinine and kidney MPO activity when compared to vehicle group. At a molecular level these effects of C-peptide were associated with reduced expression of the c-Fos subunit and reduced activation of the pro-inflammatory kinases, extracellular signal-regulated kinase (ERK 1/2) and c-Jun N-terminal kinase (JNK) and subsequently, reduced DNA binding of activator protein-1 (AP-1) in the kidney. Thus, our data suggest that C-peptide may exert reno-protective effects following hemorrhagic shock by modulating AP-1 signaling

C-peptide, a novel inhibitor of lung inflammation following hemorrhagic shock

C-peptide is a 31-amino acid peptide cleaved from proinsulin during insulin synthesis. Initially thought to be inert, C-peptide may modulate the inflammatory response in the setting of endotoxemia and ischemia reperfusion. However, the spectrum of its biological effects is unclear. We hypothesized that exogenous administration of C-peptide would modulate pro- and anti-inflammatory signaling pathways and thereby attenuate lung inflammation in an in vivo model of hemorrhagic shock. Hemorrhagic shock was induced in male Wistar rats (aged 3–4 mo) by withdrawing blood to a mean arterial pressure of 50 mmHg. At 3 h after hemorrhage, rats were rapidly resuscitated by returning their shed blood. At the time of resuscitation and every hour thereafter, animals received C-peptide (280 nmol/kg) or vehicle parenterally. Animals were euthanized at 1 and 3 h after resuscitation. C-peptide administration at resuscitation following hemorrhagic shock ameliorated hypotension and blunted the systemic inflammatory response by reducing plasma levels of IL-1, IL-6, macrophage inflammatory protein-1α, and cytokine-induced neutrophil chemoattractant-1. This was associated with a reduction in lung neutrophil infiltration and plasma levels of receptor for advanced glycation end products. Mechanistically, C-peptide treatment was associated with reduced expression of proinflammatory transcription factors activator protein-1 and NF-κB and activation of the anti-inflammatory transcription factor peroxisome proliferator-activated receptor-γ. Our data suggest that C-peptide ameliorates the inflammatory response and lung inflammation following hemorrhagic shock. These effects may be modulated by altering the balance between pro- and anti-inflammatory signaling in the lung