Accuracy of free-breathing multi-parametric SASHA in identifying T1 and T2 elevations in pediatric orthotopic heart transplant patients.

T1/T2 parametric mapping may reveal patterns of elevation ("hotspots") in myocardial diseases, such as rejection in orthotopic heart transplant (OHT) patients. This study aimed to evaluate the diagnostic accuracy of free-breathing (FB) multi-parametric SAturation recovery single-SHot Acquisition (mSASHA) T1/T2 mapping in identifying hotspots present on conventional Breath-held Modified Look-Locker Inversion recovery (BH MOLLI) T1 and T2-prepared balanced steady-state free-precession (BH T2p-bSSFP) maps in pediatric OHT patients. Pediatric OHT patients underwent noncontrast 1.5T CMR with BH MOLLI T1 and T2p-bSSFP and prototype FB mSASHA T1/T2 mapping in 8 short-axis slices. FB and BH T1/T2 hotspots were segmented using semi-automated thresholding (ITK-SNAP) and their 3D coordinate locations were collected (3-Matic, Materialise, Leuven, Belgium). Receiver operator characteristic curve analysis and measures of central tendency were utilized. 40 imaging datasets from 23 pediatric OHT patients were obtained. FB mSASHA yielded a sensitivity of 82.8% for T1 and 80% for T2 maps when compared to the standard BH MOLLI, as well as 100% specificity for both T1 and T2 maps. When identified on both FB and BH maps, hotspots overlapped in all cases, with an average long axis offset between FB and BH hotspot centers of 5.8 mm (IQR 3.5-8.2) on T1 and 5.9 mm (IQR 3.5-8.2) on T2 maps. FB mSASHA T1/T2 maps can identify hotspots present on conventional BH T1/T2 maps in pediatric patients with OHT, with high sensitivity, specificity, and overlap in 3D space. Free-breathing mapping may improve patient comfort and facilitate OHT assessment in younger patient populations.

Outcomes and characteristics of cardiac arrest in children with pulmonary hypertension: A secondary analysis of the ICU-RESUS clinical trial.

BACKGROUND: Previous studies have identified pulmonary hypertension (PH) as a relatively common diagnosis in children with in-hospital cardiac arrest (IHCA), and preclinical laboratory studies have found poor outcomes and low systemic blood pressures during CPR for PH-associated cardiac arrest. The objective of this study was to determine the prevalence of PH among children with IHCA and the association between PH diagnosis and intra-arrest physiology and survival outcomes. METHODS: This was a prospectively designed secondary analysis of patients enrolled in the ICU-RESUS clinical trial (NCT02837497). The primary exposure was a pre-arrest diagnosis of PH. The primary survival outcome was survival to hospital discharge with favorable neurologic outcome (Pediatric Cerebral Performance Category score 1-3 or unchanged from baseline). The primary physiologic outcome was event-level average diastolic blood pressure (DBP) during CPR. RESULTS: Of 1276 patients with IHCAs during the study period, 1129 index IHCAs were enrolled; 184 (16.3%) had PH and 101/184 (54.9%) were receiving inhaled nitric oxide at the time of IHCA. Survival with favorable neurologic outcome was similar between patients with and without PH on univariate (48.9% vs. 54.4%; p = 0.17) and multivariate analyses (aOR 0.82 [95%CI: 0.56, 1.20]; p = 0.32). There were no significant differences in CPR event outcome or survival to hospital discharge. Average DBP, systolic BP, and end-tidal carbon dioxide during CPR were similar between groups. CONCLUSIONS: In this prospective study of pediatric IHCA, pre-existing PH was present in 16% of children. Pre-arrest PH diagnosis was not associated with statistically significant differences in survival outcomes or intra-arrest physiologic measures.

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.

Native T1 mapping detects both acute clinical rejection and graft dysfunction in pediatric heart transplant patients.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is emerging as an important tool for cardiac allograft assessment. Native T1 mapping may add value in identifying rejection and in assessing graft dysfunction and myocardial fibrosis burden. We hypothesized that CMR native T1 values and features of textural analysis of T1 maps would identify acute rejection, and in a secondary analysis, correlate with markers of graft dysfunction, and with fibrosis percentage from endomyocardial biopsy (EMB). METHODS: Fifty cases with simultaneous EMB, right heart catheterization, and 1.5 T CMR with breath-held T1 mapping via modified Look-Locker inversion recovery (MOLLI) in 8 short-axis slices and subsequent quantification of mean and peak native T1 values, were performed on 24 pediatric subjects. A single mid-ventricular slice was used for image texture analysis using nine gray-level co-occurrence matrix features. Digital quantification of Masson trichrome stained EMB samples established degree of fibrosis. Markers of graft dysfunction, including serum brain natriuretic peptide levels and hemodynamic measurements from echocardiography, catheterization, and CMR were collated. Subjects were divided into three groups based on degree of rejection: acute rejection requiring new therapy, mild rejection requiring increased ongoing therapy, and no rejection with no change in treatment. Statistical analysis included student's t-test and linear regression. RESULTS: Peak and mean T1 values were significantly associated with acute rejection, with a monotonic trend observed with increased grade of rejection. Texture analysis demonstrated greater spatial heterogeneity in T1 values, as demonstrated by energy, entropy, and variance, in cases requiring treatment. Interestingly, 2 subjects who required increased therapy despite low grade EMB results had abnormal peak T1 values. Peak T1 values also correlated with increased BNP, right-sided filling pressures, and capillary wedge pressures. There was no difference in histopathological fibrosis percentage among the 3 groups; histopathological fibrosis did not correlate with T1 values or markers of graft dysfunction. CONCLUSION: In pediatric heart transplant patients, native T1 values identify acute rejection requiring treatment and may identify graft dysfunction. CMR shows promise as an important tool for evaluation of cardiac grafts in children, with T1 imaging outperforming biopsy findings in the assessment of rejection.

Characterization of Inhaled Nitric Oxide Use for Cardiac Indications in Pediatric Patients.

OBJECTIVES: Characterize the use of inhaled nitric oxide (iNO) for pediatric cardiac patients and assess the relationship between patient characteristics before iNO initiation and outcomes following cardiac surgery. DESIGN: Observational cohort study. SETTING: PICU and cardiac ICUs in seven Collaborative Pediatric Critical Care Research Network hospitals. PATIENTS: Consecutive patients, less than 18 years old, mechanically ventilated before or within 24 hours of iNO initiation. iNO was started for a cardiac indication and excluded newborns with congenital diaphragmatic hernia, meconium aspiration syndrome, and persistent pulmonary hypertension, or when iNO started at an outside institution. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Four-hundred seven patients with iNO initiation based on cardiac dysfunction. Cardiac dysfunction patients were administered iNO for a median of 4 days (2-7 d). There was significant morbidity with 51 of 407 (13%) requiring extracorporeal membrane oxygenation and 27 of 407 (7%) requiring renal replacement therapy after iNO initiation, and a 28-day mortality of 46 of 407 (11%). Of the 366 (90%) survivors, 64 of 366 patients (17%) had new morbidity as assessed by Functional Status Scale. Among the postoperative cardiac surgical group (n = 301), 37 of 301 (12%) had a superior cavopulmonary connection and nine of 301 (3%) had a Fontan procedure. Based on echocardiographic variables prior to iNO (n = 160) in the postoperative surgical group, right ventricle dysfunction was associated with 28-day and hospital mortalities (both, p < 0.001) and ventilator-free days (p = 0.003); tricuspid valve regurgitation was only associated with ventilator-free days (p < 0.001), whereas pulmonary hypertension was not associated with mortality or ventilator-free days. CONCLUSIONS: Pediatric patients in whom iNO was initiated for a cardiac indication had a high mortality rate and significant morbidity. Right ventricular dysfunction, but not the presence of pulmonary hypertension on echocardiogram, was associated with ventilator-free days and mortality.

Dynamic PEEP Study: A Non-invasive Diagnostic Exam to Assess for Effective PEEP in Children with Severe BPD.

OBJECTIVE: Tracheobronchomalacia (TBM) is common in neonates with bronchopulmonary dysplasia (BPD) and is associated with higher morbidity. This study evaluates the value of a CT protocol to assess the degree of TBM and gauge the adequacy of prescribed PEEP. STUDY DESIGN: Four infants with severe BPD on invasive mechanical ventilation underwent a chest CT protocol, including limited reduced-dose expiratory scans with varying PEEP levels. RESULTS: Baseline PEEP was adjusted in all subjects after performing the Dynamic PEEP CT. In two infants, the PEEP was increased due to significant TBM and in the other two without signs of TBM PEEP was decreased. The clinical course improved in all patients after adjusting PEEP. CONCLUSION: A "Dynamic PEEP" study may be reliable and non-invasive imaging modality for the evaluation of adequate ventilator settings in infants with severe BPD who are not optimal candidates for bronchoscopy.

Evaluating Vitamin C in Septic Shock: A Randomized Controlled Trial of Vitamin C Monotherapy.

OBJECTIVES: To determine whether IV vitamin C therapy reduces 28-day mortality in patients with septic shock. DESIGN: Multicenter, double-blinded, randomized controlled trial. SETTING: One academic medical ICU and four community ICUs. PATIENTS: Of 167 adult patients within 24 hours of vasopressor initiation for septic shock, 126 consented to participation, and 124 received study drug and were included in analysis. INTERVENTIONS: IV vitamin C (10 mg/mL in normal saline) administered as a 1,000-mg bolus over 30 minutes followed by continuous infusion of 250 mg/hr for 96 hours or placebo of equal volumes of normal saline. MEASUREMENTS AND MAIN RESULTS: Of 124 subjects receiving study drug and included in analysis, 60 received vitamin C and 64 placebo. The primary outcome of all-cause 28-day mortality (vitamin C, 26.7%; placebo, 40.6%; p = 0.10) was lower in the vitamin C arm but did not reach statistical significance. Initiation of renal replacement therapy was higher in the vitamin C arm (vitamin C, 16.7%; placebo, 3.3%; p = 0.015), as was volume of fluid administration within 6 hours of study drug initiation (vitamin C, 1.07 L; placebo, 0.76 L; p = 0.03). There were no statistically significant differences in other secondary outcomes. In post hoc subgroup analysis, there was a decrease in 28-day mortality in the vitamin C arm among patients requiring positive-pressure ventilation at the time of enrollment (vitamin C, 36.3%; placebo, 60.0%; p = 0.05). This trial is registered at clinicaltrials.gov under identifier NCT03338569. CONCLUSIONS: Vitamin C monotherapy failed to significantly reduce mortality in septic shock patients as hypothesized. Our findings do not support its routine clinical use for this purpose.

Inhaled Nitric Oxide Use and Outcomes in Critically Ill Children With a History of Prematurity.

BACKGROUND: Inhaled nitric oxide (INO) is used to treat hypoxic respiratory failure without clear evidence of benefit. Future trials to evaluate its use will be designed based on an understanding of the populations in which this therapy is provided and with outcomes based on patient characteristics, for example, a history of premature birth. METHODS: This was a multi-center prospective observational study that evaluated subjects in the pediatric ICU who were treated with INO for a respiratory indication, excluding those treated in the neonatal ICU or treated for birth-related disease. We used logistic regression to evaluate characteristics associated with mortality and duration of mechanical ventilation. Specifically, we compared subjects born early preterm (<32 weeks post-conceptual age), late preterm (32-37 weeks post-conceptual age), and full term. RESULTS: A total of 163 children (median age [interquartile range], 1.8 [0.7-6.0] y) were included, 41 (25.2%) had a history of preterm birth (18 born early preterm and 23 born late preterm). INO was initiated for less-severe lung disease in the early preterm versus late preterm versus full-term subjects (median mean airway pressures, 16 vs 19 vs 19 cm H2O; P = .03), although the oxygenation index and oxygenation saturation index did not differ. The early preterm subjects had more ventilator-free days (median, 18.0, 7.0, 4.5 d; P = .02) and lower 28-d mortality (0, 26.1, 32.0%; P = .007). Lower respiratory tract disease, but not a history of prematurity, was independently associated with lower mortality. CONCLUSIONS: INO was used differently in early preterm subjects. Clinical trials that evaluate INO use should have standardized oxygenation deficit thresholds for initiation of therapy and should consider stratifying by early preterm status.

Modeling Electro-Chemo-Mechanical Behaviors within the Dense BaZr0.8Y0.2O3-δ Protonic-Ceramic Membrane in a Long Tubular Electrochemical Cell.

This paper reports an extended Nernst-Planck computational model that couples charged-defect transport and stress in tubular electrochemical cell with a ceramic proton-conducting membrane. The model is particularly concerned with coupled chemo-mechanical behaviors, including how electrochemical phenomena affect internal stresses and vice versa. The computational model predicts transient and steady-state defect concentrations, fluxes, stresses within a thin BaZr0.8Y0.2O3-δ (BZY20) membrane. Depending on the polarization (i.e., imposed current density), the model predicts performance as a fuel cell or an electrolyzer. A sensitivity analysis reveals the importance of thermodynamic and transport properties, which are often not readily available.

Common carotid artery imaging after vessel sparing decannulation from Extracorporeal Membrane Oxygenation (ECMO) support.

INTRODUCTION: In 2008, Children's National Hospital adopted a simple vessel sparing technique (VST) for neck extra corporeal membrane (ECMO) cannulation/decannulation that is technically simple and reproducible. In this study, we review a cohort of patients decannulated from venous-arterial (VA) ECMO using a VST with the goal of understanding flow dynamics and anatomic changes of the common carotid artery (CCA) after repair with a VST. METHODS: Patients supported with ECMO at a single, tertiary care center between 2008 and 2019 were identified. Patients were included in the analysis if they survived VA ECMO including VST decannulation and neck vessel imaging was completed with either magnetic resonance angiogram (MRA) or computerized tomography angiogram (CTA) post decannulation. The right CCA was assessed for patency and arteriopathy. Complications and feasibility of repeat ECMO cannulation via the neck vessels were also investigated. RESULTS: Three hundred and nineteen patients were identified as having received ECMO support in either the PICU or CICU between 2008 and 2019, of which 76 survived VA ECMO support via neck cannulation. Neck vessel imaging was obtained in 21 patients. Ten had imaging demonstrating a normal right CCA. The CCA was occluded in 3 and stenotic in 5. Vessel wall defects were present in 4. No definitive complication was associated with any of the arterial abnormalities. Repeat right CCA cannulation was achieved in 6/7 patients who needed additional VA ECMO support. CONCLUSIONS: Repair of the right CCA with a simple VST can be achieved safely and consistently during VA ECMO support in pediatric patients. Vascular imaging of the right CCA was normal in almost half and repeat cannulation was achieved in most when pursued. Stenosis and vessel wall defects were common, thus neck vessel imaging post decannulation may be warranted for all patients with a right CCA repair after ECMO support.

Plasma and Urinary FGF-2 and VEGF-A Levels Identify Children at Risk for Severe Bleeding after Pediatric Cardiopulmonary Bypass: A Pilot Study.

Severe bleeding after cardiothoracic surgery with cardiopulmonary bypass (CPB) is associated with increased morbidity and mortality in adults and children. Fibroblast Growth Factor-2 (FGF-2) and Vascular Endothelial Growth Factor-A (VEGF-A) induce hemorrhage in murine models with heparin exposure. We aim to determine if plasma and urine levels of FGF-2 and VEGF-A in the immediate perioperative period can identify children with severe bleeding after CPB. We performed a prospective, observational biomarker study in 64 children undergoing CPB for congenital heart disease repair from June 2015 - January 2017 in a tertiary pediatric referral center. Primary outcome was severe bleeding defined as ≥ 20% estimated blood volume loss within 24-hours. Independent variables included perioperative plasma and urinary FGF-2 and VEGF-A levels. Analyses included comparative (Wilcoxon rank sum, Fisher's exact, and Student's t tests) and discriminative (receiver operator characteristic [ROC] curve) analyses. Forty-eight (75%) children developed severe bleeding. Median plasma and urinary FGF-2 and VEGF-A levels were elevated in children with severe bleeding compared to without bleeding (preoperative: plasma FGF-2 = 16[10-35] vs. 9[2-13] pg/ml; urine FGF-2= 28[15-76] vs. 14.5[1.5-22] pg/mg; postoperative: plasma VEGF-A = 146[34-379] vs. 53 [0-134] pg/ml; urine VEGF-A = 132 [52-257] vs. 45[0.1-144] pg/mg; all p < 0.05). ROC curve analyses of combined plasma and urinary FGF-2 and VEGF-A levels discriminated severe postoperative bleeding (AUC: 0.73-0.77) with mean sensitivity and specificity above 80%. We conclude that the perioperative plasma and urinary levels of FGF-2 and VEGF-A discriminate risk of severe bleeding after pediatric CPB.

Association between time of day and CPR quality as measured by CPR hemodynamics during pediatric in-hospital CPR.

INTRODUCTION: Patients who suffer in-hospital cardiac arrest (IHCA) are less likely to survive if the arrest occurs during nighttime versus daytime. Diastolic blood pressure (DBP) as a measure of chest compression quality was associated with survival from pediatric IHCA. We hypothesized that DBP during CPR for IHCA is lower during nighttime versus daytime. METHODS: This is a secondary analysis of data collected from the Pediatric Intensive Care Quality of Cardiopulmonary Resuscitation Study. Pediatric or Pediatric Cardiac Intensive Care Unit patients who received chest compressions for ≥1 min and who had invasive arterial BP monitoring were enrolled. Nighttime was defined as 11:00PM to 6:59AM and daytime as 7:00AM until 10:59PM. Primary outcome was attainment of DBP ≥ 25 mmHg in infants <1 year and ≥30 mmHg in older children. Secondary outcomes were mean DBP, ROSC, and survival to hospital discharge. Univariable and multivariate analyses evaluated the relationships between time (nighttime vs. daytime) and outcomes. RESULTS: Between July 1, 2013 and June 30, 2016, 164 arrests met all inclusion/exclusion criteria: 45(27%) occurred at nighttime and 119(73%) during daytime. Average DBPs achieved were not different between groups (DBP: nighttime 28.3 mmHg[25.3, 36.5] vs. daytime 29.6 mmHg[21.8, 38.0], p = 0.64). Relative risk of DBP threshold met during nighttime vs. daytime was 1.27, 95%CI [0.80, 1.98], p = 0.30. There was no significant nighttime vs. daytime difference in ROSC (28/45[62%] vs. 84/119[71%] p = 0.35) or survival to hospital discharge (16/45[36%] vs. 61/119[51%], p = 0.08). CONCLUSIONS: In this cohort of pediatric ICU patients with IHCA, there was no significant difference in DBP during CPR between nighttime and daytime.

Survival and Hemodynamics During Pediatric Cardiopulmonary Resuscitation for Bradycardia and Poor Perfusion Versus Pulseless Cardiac Arrest.

OBJECTIVES: The objective of this study was to compare survival outcomes and intra-arrest arterial blood pressures between children receiving cardiopulmonary resuscitation for bradycardia and poor perfusion and those with pulseless cardiac arrests. DESIGN: Prospective, multicenter observational study. SETTING: PICUs and cardiac ICUs of the Collaborative Pediatric Critical Care Research Network. PATIENTS: Children (< 19 yr old) who received greater than or equal to 1 minute of cardiopulmonary resuscitation with invasive arterial blood pressure monitoring in place. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 164 patients, 96 (59%) had bradycardia and poor perfusion as the initial cardiopulmonary resuscitation rhythm. Compared to those with initial pulseless rhythms, these children were younger (0.4 vs 1.4 yr; p = 0.005) and more likely to have a respiratory etiology of arrest (p < 0.001). Children with bradycardia and poor perfusion were more likely to survive to hospital discharge (adjusted odds ratio, 2.31; 95% CI, 1.10-4.83; p = 0.025) and survive with favorable neurologic outcome (adjusted odds ratio, 2.21; 95% CI, 1.04-4.67; p = 0.036). There were no differences in diastolic or systolic blood pressures or event survival (return of spontaneous circulation or return of circulation via extracorporeal cardiopulmonary resuscitation). Among patients with bradycardia and poor perfusion, 49 of 96 (51%) had subsequent pulselessness during the cardiopulmonary resuscitation event. During cardiopulmonary resuscitation, these patients had lower diastolic blood pressure (point estimate, -6.68 mm Hg [-10.92 to -2.44 mm Hg]; p = 0.003) and systolic blood pressure (point estimate, -12.36 mm Hg [-23.52 to -1.21 mm Hg]; p = 0.032) and lower rates of return of spontaneous circulation (26/49 vs 42/47; p < 0.001) than those who were never pulseless. CONCLUSIONS: Most children receiving cardiopulmonary resuscitation in ICUs had an initial rhythm of bradycardia and poor perfusion. They were more likely to survive to hospital discharge and survive with favorable neurologic outcomes than patients with pulseless arrests, although there were no differences in immediate event outcomes or intra-arrest hemodynamics. Patients who progressed to pulselessness after cardiopulmonary resuscitation initiation had lower intra-arrest hemodynamics and worse event outcomes than those who were never pulseless.

Inhaled Nitric Oxide Use in Pediatric Hypoxemic Respiratory Failure.

OBJECTIVES: To characterize contemporary use of inhaled nitric oxide in pediatric acute respiratory failure and to assess relationships between clinical variables and outcomes. We sought to study the relationship of inhaled nitric oxide response to patient characteristics including right ventricular dysfunction and clinician responsiveness to improved oxygenation. We hypothesize that prompt clinician responsiveness to minimize hyperoxia would be associated with improved outcomes. DESIGN: An observational cohort study. SETTING: Eight sites of the Collaborative Pediatric Critical Care Research Network. PATIENTS: One hundred fifty-one patients who received inhaled nitric oxide for a primary respiratory indication. MEASUREMENTS AND MAIN RESULTS: Clinical data were abstracted from the medical record beginning at inhaled nitric oxide initiation and continuing until the earliest of 28 days, ICU discharge, or death. Ventilator-free days, oxygenation index, and Functional Status Scale were calculated. Echocardiographic reports were abstracted assessing for pulmonary hypertension, right ventricular dysfunction, and other cardiovascular parameters. Clinician responsiveness to improved oxygenation was determined. One hundred thirty patients (86%) who received inhaled nitric oxide had improved oxygenation by 24 hours. PICU mortality was 29.8%, while a new morbidity was identified in 19.8% of survivors. Among patients who had echocardiograms, 27.9% had evidence of pulmonary hypertension, 23.1% had right ventricular systolic dysfunction, and 22.1% had an atrial communication. Moderate or severe right ventricular dysfunction was associated with higher mortality. Clinicians responded to an improvement in oxygenation by decreasing FIO2 to less than 0.6 within 24 hours in 71% of patients. Timely clinician responsiveness to improved oxygenation with inhaled nitric oxide was associated with more ventilator-free days but not less cardiac arrests, mortality, or additional morbidity. CONCLUSIONS: Clinician responsiveness to improved oxygenation was associated with less ventilator days. Algorithms to standardize ventilator management may improve signal to noise ratios in future trials enabling better assessment of the effect of inhaled nitric oxide on patient outcomes. Additionally, confining studies to more selective patient populations such as those with right ventricular dysfunction may be required.

Survival and Cardiopulmonary Resuscitation Hemodynamics Following Cardiac Arrest in Children With Surgical Compared to Medical Heart Disease.

OBJECTIVES: To assess the association of diastolic blood pressure cutoffs (≥ 25 mm Hg in infants and ≥ 30 mm Hg in children) during cardiopulmonary resuscitation with return of spontaneous circulation and survival in surgical cardiac versus medical cardiac patients. Secondarily, we assessed whether these diastolic blood pressure targets were feasible to achieve and associated with outcome in physiology unique to congenital heart disease (single ventricle infants, open chest), and influenced outcomes when extracorporeal cardiopulmonary resuscitation was deployed. DESIGN: Multicenter, prospective, observational cohort analysis. SETTING: Tertiary PICU and cardiac ICUs within the Collaborative Pediatric Critical Care Research Network. PATIENTS: Patients with invasive arterial catheters during cardiopulmonary resuscitation and surgical cardiac or medical cardiac illness category. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Hemodynamic waveforms during cardiopulmonary resuscitation were analyzed on 113 patients, 88 surgical cardiac and 25 medical cardiac. A similar percent of surgical cardiac (51/88; 58%) and medical cardiac (17/25; 68%) patients reached the diastolic blood pressure targets (p = 0.488). Achievement of diastolic blood pressure target was associated with improved survival to hospital discharge in surgical cardiac patients (p = 0.018), but not medical cardiac patients (p = 0.359). Fifty-three percent (16/30) of patients with single ventricles attained the target diastolic blood pressure. In patients with an open chest at the start of chest compressions, 11 of 20 (55%) attained the target diastolic blood pressure. In the 33 extracorporeal cardiopulmonary resuscitation patients, 16 patients (48%) met the diastolic blood pressure target with no difference between survivors and nonsurvivors (p = 0.296). CONCLUSIONS: During resuscitation in an ICU, with invasive monitoring in place, diastolic blood pressure targets of greater than or equal to 25 mm Hg in infants and greater than or equal to 30 mm Hg in children can be achieved in patients with both surgical and medical heart disease. Achievement of diastolic blood pressure target was associated with improved survival to hospital discharge in surgical cardiac patients, but not medical cardiac patients. Diastolic blood pressure targets were feasible to achieve in 1) single ventricle patients, 2) open chest physiology, and 3) extracorporeal cardiopulmonary resuscitation patients.

Functional outcomes among survivors of pediatric in-hospital cardiac arrest are associated with baseline neurologic and functional status, but not with diastolic blood pressure during CPR.

AIM: Diastolic blood pressure (DBP) during cardiopulmonary resuscitation (CPR) is associated with survival following pediatric in-hospital cardiac arrest. The relationship between intra-arrest haemodynamics and neurological status among survivors of pediatric cardiac arrest is unknown. METHODS: This study represents analysis of data from the prospective multicenter Pediatric Intensive Care Quality of cardiopulmonary resuscitation (PICqCPR) Study. Primary predictor variables were median DBP and median systolic blood pressure (SBP) over the first 10min of CPR. The primary outcome measure was "new substantive morbidity" determined by Functional Status Scale (FSS) and defined as an increase in the FSS of at least 3 points or increase of 2 in a single FSS domain. Univariable analyses were completed to investigate the relationship between new substantive morbidity and BPs during CPR. RESULTS: 244 index CPR events occurred during the study period, 77 (32%) CPR events met all inclusion criteria as well as having both DBP and FSS data available. Among 77 survivors, 32 (42%) had new substantive morbidity as measured by the FSS score. No significant differences were identified in DBP (median 30.5mmHg vs. 30.9mmHg, p=0.5) or SBP (median 76.3mmHg vs. 63.0mmHg, p=0.2) between patients with and without new substantive morbidity. Children who developed new substantive morbidity were more likely to have lower pre-arrest FSS than those that did not (median [IQR]: 7.5 [6.0-9.0] versus 9.0 [7.0-13.0], p=0.01). CONCLUSION: New substantive morbidity determined by FSS after a pediatric IHCA was associated with baseline functional status, but not DBP during CPR.

Ventilation Rates and Pediatric In-Hospital Cardiac Arrest Survival Outcomes.

OBJECTIVES: The objective of this study was to associate ventilation rates during in-hospital cardiopulmonary resuscitation with 1) arterial blood pressure during cardiopulmonary resuscitation and 2) survival outcomes. DESIGN: Prospective, multicenter observational study. SETTING: Pediatric and pediatric cardiac ICUs of the Collaborative Pediatric Critical Care Research Network. PATIENTS: Intubated children (≥ 37 wk gestation and < 19 yr old) who received at least 1 minute of cardiopulmonary resuscitation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Arterial blood pressure and ventilation rate (breaths/min) were manually extracted from arterial line and capnogram waveforms. Guideline rate was defined as 10 ± 2 breaths/min; high ventilation rate as greater than or equal to 30 breaths/min in children less than 1 year old, and greater than or equal to 25 breaths/min in older children. The primary outcome was survival to hospital discharge. Regression models using Firth penalized likelihood assessed the association between ventilation rates and outcomes. Ventilation rates were available for 52 events (47 patients). More than half of patients (30/47; 64%) were less than 1 year old. Eighteen patients (38%) survived to discharge. Median event-level average ventilation rate was 29.8 breaths/min (interquartile range, 23.8-35.7). No event-level average ventilation rate was within guidelines; 30 events (58%) had high ventilation rates. The only significant association between ventilation rate and arterial blood pressure occurred in children 1 year old or older and was present for systolic blood pressure only (-17.8 mm Hg/10 breaths/min; 95% CI, -27.6 to -8.1; p < 0.01). High ventilation rates were associated with a higher odds of survival to discharge (odds ratio, 4.73; p = 0.029). This association was stable after individually controlling for location (adjusted odds ratio, 5.97; p = 0.022), initial rhythm (adjusted odds ratio, 3.87; p = 0.066), and time of day (adjusted odds ratio, 4.12; p = 0.049). CONCLUSIONS: In this multicenter cohort, ventilation rates exceeding guidelines were common. Among the range of rates delivered, higher rates were associated with improved survival to hospital discharge.

The association of immediate post cardiac arrest diastolic hypertension and survival following pediatric cardiac arrest.

AIM: In-hospital cardiac arrest occurs in >5000 children each year in the US and almost half will not survive to discharge. Animal data demonstrate that an immediate post-resuscitation burst of hypertension is associated with improved survival. We aimed to determine if systolic and diastolic invasive arterial blood pressures immediately (0-20 min) after return of spontaneous circulation (ROSC) are associated with survival and neurologic outcomes at hospital discharge. METHODS: This is a secondary analysis of the Pediatric Intensive Care Quality of CPR (PICqCPR) study of invasively measured blood pressures during intensive care unit CPR. Patients were eligible if they achieved ROSC and had at least one invasively measured blood pressure within the first 20 min following ROSC. Post-ROSC blood pressures were normalized for age, sex and height. "Immediate hypertension" was defined as at least one systolic or diastolic blood pressure >90th percentile. The primary outcome was survival to hospital discharge. RESULTS: Of 102 children, 70 (68.6%) had at least one episode of immediate post-CPR diastolic hypertension. After controlling for pre-existing hypotension, duration of CPR, calcium administration, and first documented rhythm, patients with immediate post-CPR diastolic hypertension were more likely to survive to hospital discharge (79.3% vs. 54.5%; adjusted OR = 2.93; 95%CI, 1.16-7.69). CONCLUSIONS: In this post hoc secondary analysis of the PICqCPR study, 68.6% of subjects had diastolic hypertension within 20 min of ROSC. Immediate post-ROSC hypertension was associated with increased odds of survival to discharge, even after adjusting for covariates of interest.

Clinical Determination of Brain Death in Children Supported by Extracorporeal Membrane Oxygenation.

BACKGROUND/OBJECTIVE: Children supported by extracorporeal membrane oxygenation (ECMO) are at risk of catastrophic neurologic injury and brain death. Timely determination of brain death is important for minimizing psychological distress for families, resource allocation, and organ donation. Reports of successful determination of brain death in pediatric patients supported by ECMO are limited. The determination of brain death by clinical criteria requires apnea testing, which has historically been viewed as challenging in patients supported by ECMO. We report eight pediatric patients who underwent a total of 14 brain death examinations, including apnea testing, while supported by veno-arterial ECMO (VA-ECMO), resulting in six cases of clinical determination of brain death. METHODS: We performed a retrospective review of the medical records of pediatric patients who underwent brain death examination while supported by VA-ECMO between 2010 and 2018 at a single tertiary care children's hospital. RESULTS: Eight patients underwent brain death examination, including apnea testing, while supported by VA-ECMO. Six patients met criteria for brain death, while two had withdrawal of technical support after the first examination. During the majority of apnea tests (n = 13/14), the ECMO circuit was modified to achieve hypercarbia while maintaining oxygenation and hemodynamic stability. The sweep flow was decreased prior to apnea testing in ten brain death examinations, carbon dioxide was added to the circuit during three examinations, and ECMO pump flows were increased in response to hypotension during two examinations. CONCLUSIONS: Clinical determination of brain death, including apnea testing, can be performed in pediatric patients supported by ECMO. The ECMO circuit can be effectively modified during apnea testing to achieve a timely rise in carbon dioxide while maintaining oxygenation and hemodynamic stability.