Multisystem Inflammatory Syndrome in U.S. Children and Adolescents.

BACKGROUND: Understanding the epidemiology and clinical course of multisystem inflammatory syndrome in children (MIS-C) and its temporal association with coronavirus disease 2019 (Covid-19) is important, given the clinical and public health implications of the syndrome. METHODS: We conducted targeted surveillance for MIS-C from March 15 to May 20, 2020, in pediatric health centers across the United States. The case definition included six criteria: serious illness leading to hospitalization, an age of less than 21 years, fever that lasted for at least 24 hours, laboratory evidence of inflammation, multisystem organ involvement, and evidence of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on reverse-transcriptase polymerase chain reaction (RT-PCR), antibody testing, or exposure to persons with Covid-19 in the past month. Clinicians abstracted the data onto standardized forms. RESULTS: We report on 186 patients with MIS-C in 26 states. The median age was 8.3 years, 115 patients (62%) were male, 135 (73%) had previously been healthy, 131 (70%) were positive for SARS-CoV-2 by RT-PCR or antibody testing, and 164 (88%) were hospitalized after April 16, 2020. Organ-system involvement included the gastrointestinal system in 171 patients (92%), cardiovascular in 149 (80%), hematologic in 142 (76%), mucocutaneous in 137 (74%), and respiratory in 131 (70%). The median duration of hospitalization was 7 days (interquartile range, 4 to 10); 148 patients (80%) received intensive care, 37 (20%) received mechanical ventilation, 90 (48%) received vasoactive support, and 4 (2%) died. Coronary-artery aneurysms (z scores ≥2.5) were documented in 15 patients (8%), and Kawasaki's disease-like features were documented in 74 (40%). Most patients (171 [92%]) had elevations in at least four biomarkers indicating inflammation. The use of immunomodulating therapies was common: intravenous immune globulin was used in 144 (77%), glucocorticoids in 91 (49%), and interleukin-6 or 1RA inhibitors in 38 (20%). CONCLUSIONS: Multisystem inflammatory syndrome in children associated with SARS-CoV-2 led to serious and life-threatening illness in previously healthy children and adolescents. (Funded by the Centers for Disease Control and Prevention.).

Optimized multisite ventricular pacing in postoperative single-ventricle patients.

Ventricular dyssynchrony is associated with morbidity and mortality after palliation of a single ventricle. The authors hypothesized that resynchronization with optimized temporary multisite pacing postoperatively would be safe, feasible, and effective. Pacing was assessed in the intensive care unit within the first 24 h after surgery. Two unipolar atrial pacing leads and four bipolar ventricular pacing leads were placed at standardized sites intraoperatively. Pacing was optimized to maximize mean arterial pressure. The protocol tested 11 combinations of the 4 different ventricular lead sites, 6 atrioventricular delays (50-150 ms), and 14 intraventricular delays. Optimal pacing settings were thus determined and ultimately compared in four configurations: bipolar, unipolar, single-site atrioventricular pacing, and intrinsic rhythm. Each patient was his or her own control, and all pacing comparisons were implemented in random sequence. Single-ventricle palliation was performed for 17 children ages 0-21 years. Pacing increased mean arterial pressure (MAP) versus intrinsic rhythm, with the following configurations: bipolar multisite pacing increased MAP by 2.2 % (67.7 ± 2.4 to 69.2 ± 2.4 mmHg; p = 0.013) and unipolar multisite pacing increased MAP by 2.8 % (67.7 ± 2.4 to 69.6 ± 2.7 mmHg; p = 0.002). Atrioventricular single-site pacing increased MAP by 2.1 % (67.7 ± 2.4 to 69.1 ± 2.5 mmHg: p = 0.02, insignificant difference under Bonferroni correction). The echocardiographic fractional area change in nine patients increased significantly only with unipolar pacing (32 ± 3.1 to 36 ± 4.2 %; p = 0.02). No study-related adverse events occurred. Multisite pacing optimization is safe and feasible in the early postoperative period after single-ventricle palliation, with improvements in mean arterial pressure and fractional area shortening. Further study to evaluate clinical benefits is required.

Effects of biventricular pacing on left heart twist and strain in a porcine model of right heart failure.

BACKGROUND: Biventricular pacing (BiVP) improves cardiac output (CO) in selected cardiac surgery patients, but response remains variable, necessitating a better understanding of the mechanism. Accordingly, we used speckle tracking echocardiography (STE) to analyze BiVP during acute right ventricular pressure overload (RVPO). MATERIALS AND METHODS: In nine pigs, the inferior vena cava (IVC) was snared to decrease CO and establish a control model. Heart block was induced, the pulmonary artery snared, and BiVP initiated. Echocardiograms of the left ventricular midpapillary level were taken at varying atrioventricular delay (AVD) and interventricular delay (VVD) for STE analysis of regional circumferential strain (CS) and radial strain (RS). Echocardiograms were taken of the left ventricular base, midpapillary, and apex during baseline, IVC occlusion, and each BiVP setting for STE analysis of twist, apical and basal rotations, CS, RS, and synchrony. Indices were correlated against CO with mixed linear models. RESULTS: During IVC occlusion, CO correlated with twist, apical rotation, RS, RS synchrony, and CS (P < 0.05). During RVPO with BiVP, CO only correlated with RS synchrony and CS (P < 0.05). During AVD and VVD variations, CO was associated with free wall RS (P < 0.008). CO correlated with septal wall CS during AVD variation and free wall CS during VVD variation (P < 0.008). CONCLUSIONS: In an open chest model, twist, RS, RS synchrony, and CS analyzed by STE may be noninvasive surrogates for changes in CO. During RVPO, changes in RS synchrony and CS with varying regional strain contributions may be the primary mechanism in which BiVP improves CO. Lack of correlation of remaining indices may reflect postsystolic function.

Nitric oxide-associated pulmonary edema in children with pulmonary venous hypertension.

Nitric oxide (NO)-associated pulmonary edema is rarely reported in children; in adults, it is often associated with left-sided heart failure. We report a case series of children with NO-associated pulmonary edema, which was defined as new multilobar alveolar infiltrates and worsening hypoxemia within 24 h of initiation or escalation of NO and radiologic or clinical improvement after NO discontinuation. We identified six patients (0.4-4 years old) with ten episodes of NO-associated pulmonary edema. Diagnoses included atrioventricular canal defect with mitral valve disease (n = 2), pulmonary atresia and major aorta-pulmonary collateral arteries (n = 2), total anomalous pulmonary venous return (n = 1), and pulmonary veno-occlusive disease (n = 1). All patients had evidence of pulmonary venous hypertension, and two had mitral valve disease resulting in clinical evidence of left-sided heart failure. Pulmonary edema improved or resolved within 24 h of discontinuing NO. At cardiac catheterization, mean left atrial pressure was <15 mmHg in three of three patients (none with mitral valve disease), whereas pulmonary artery occlusion pressure was >15 mmHg in two of five patients. In conclusion, we describe six young children with NO-associated pulmonary edema and pulmonary venous hypertension. Only two of these children had left-sided heart failure: Left atrial pressure as well as pulmonary artery occlusion pressure may not be helpful in identifying children at risk for NO-associated pulmonary edema.

Survey of Pediatric Critical Care Fellows on Postresuscitation Debriefing.

Purpose: Current guidelines recommend debriefing following medical resuscitations to improve patient outcomes. The goal of this study was to describe national trends in postresuscitation debriefing practices among pediatric critical care medicine (PCCM) fellows to identify potential gaps in fellow education. Methods: A 13-item survey was distributed to fellows in all 76 ACGME-accredited PCCM programs in the United States in the spring of 2021. The online survey addressed frequency and timing of debriefings following medical resuscitations, whether formal training is provided, which medical professionals are present, and providers' comfort level leading a debriefing. Results were analyzed using descriptive statistics. Results: A total of 102 responses (out of a possible N of 536) were gathered from current PCCM fellows. All fellows (100%) reported participation in a medical resuscitation. Only 21% stated that debriefings occurred after every resuscitation event, and 44% did not follow a structured protocol for debriefing. While 66% reported feeling very or somewhat comfortable leading the debriefing, 19% felt either somewhat uncomfortable or very uncomfortable. A vast majority (92%) of participating fellows believed that debriefing would be helpful in improving team member performance during future resuscitations, and 92% expressed interest in learning more about debriefing. Conclusions: The majority of PCCM fellows do not receive formal training on how to lead a debriefing. Given that 74% of fellows in our study did not feel very comfortable leading a debriefing but almost universally expressed that this practice is useful for provider well-being and performance, there is a clear need for increased incorporation of debriefing training into PCCM curricula across the United States.

A Novel Code Team Leader Card to Improve Leader Identification.

Prompt and clear code team leader identification is vital in effective cardiopulmonary resuscitation (CPR), and pediatric trainees often have limited experience in these scenarios. This project sought to develop a tangible object that provided clear leader identification and assisted in code team management and simulated team training. A Code Team Leader Card (CTLC) was designed to provide clear leader identification while simultaneously providing a cognitive aid via integration of pediatric advanced life support (PALS) algorithms. Additionally, CTLC served to occupy the leader's hands to limit their ability to intervene on procedural tasks. The CTLC was incorporated into pediatric resident simulation training, and pre- and postintervention survey data were analyzed. Analysis particularly focused on whether "a leader was clearly identified by all team members." The relationship between CTLC implementation and consistent leader recognition was evaluated using chi-squared test, and secondary qualitative data were obtained via debriefing sessions. Pediatric residents completed 131 surveys prior to CTLC implementation and 41 surveys after implementation. Consistent code team leader recognition increased significantly from 61.8% (81 of 131) pre-CTLC to 80.5% (33 of 41) after introduction of CTLC (P=0.027). Participants commented on the benefits of CTLC during debriefing sessions. Use of a CTLC significantly improved leader recognition during simulated CPR. Inclusion of PALS algorithms led to normalization and increased utilization of these adjunct materials. The CTLC provided a secondary benefit of occupying the leader's hands, thereby allowing that person to focus on overseeing the team rather than assisting with procedural tasks.

Diagnostic challenges in a child with familial hemophagocytic lymphohistiocytosis type 3 (FHLH3) presenting with fulminant neurological disease.

BACKGROUND: Familial hemophagocytic lymphohistiocytosis (FHLH) is an autosomal recessively inherited multisystem disease characterized by fever, rash, splenomegaly, cytopenias, and variable central nervous system (CNS) manifestations. CASE HISTORY: We report the case of a 3-year-old boy who presented with splenomegaly and normocytic anemia 4 months after returning to the US from a region endemic for Leishmania infection. The child later developed progressive neurological impairment and had radiologic evidence of widespread demyelinating disease. Gene studies showed homozygosity for a mutation at Munc13-4, confirming FHLH type 3. DISCUSSION: The diagnostic uncertainty that accompanies FHLH was compounded by our patient's travel history and CNS disease mimicking acute disseminated encephalomyelitis (ADEM). Diagnostic criteria for hemophagocytic lymphohistiocytosis were not consistently met, despite aggressive disease. CONCLUSIONS: FHLH may present with fulminant demyelinating disease, mimicking ADEM, and without necessarily meeting previously defined clinical and laboratory criteria. We strongly recommend expeditious molecular testing and genetic counseling for FHLH mutations in cases of undiagnosed inflammatory CNS disease in the pediatric population.

Strychnine: Old Remedy, Silent Killer.

Toxin ingestion is a significant public health issue for children, accounting for hundreds of visits per day to emergency departments. The most common substances are household cleaning products, personal care products, and medications. This article describes an ingestion of a rare substance called strychnine, which is a plant-based odorless powder that was previously used as a nonspecific stimulant. This toxicity can mimic other ingestions, thus delaying diagnosis, so an increased awareness of the common symptoms and laboratory findings may lead to a more targeted management of strychnine poisoning. [Pediatr Ann. 2019;48(5):e205-e207.].

Weight-for-Age Percentile as a Pediatric Predictor of Emergency Department Outcome.

This study is a retrospective cohort study that examines the association between weight-for-age percentile and pediatric admission incidence from the emergency department (ED) for all diagnoses. The charts of 1432 pediatric patients under 18 years with ED visits from 2013 to 2015 at a tertiary children's hospital were reviewed. Analyses of subject age/weight stratifications were performed, along with ED disposition, reason for visit, and Emergency Severity Index (ESI). Multivariable logistic regression models were used to evaluate the independent effect of weight-for-age percentile on ED disposition while controlling for age, ESI, and reason for visit. Underweight subjects were more likely to be admitted than their normal weight counterparts when analyzed overall (odds ratio [OR] = 2.58, P < .01) and by age: less than 2.0 years of age (OR = 2.04, P = .033), between 2.01 and 6.0 years of age (OR = 8.60, P = .004), and between 6.01 and 13.0 years of age (OR = 3.83, P = .053). Younger age (OR = 0.935, P < .001) and higher acuity (OR = 3.49, P < .001) were also significant predictors of admission. No significant associations were found between weight and likelihood of admission for patients older than 13.01 years or between overweight/obese weight categories and admission for any age subgroups. This study suggests that underweight children younger than 13 years are at higher risk to be admitted from the ED than their normal weight, overweight, and obese counterparts. Even when controlling for other key factors, such as the ESI, a lower weight-for-age percentile was a reliable predictor of hospitalization.

Temporary biventricular pacing decreases the vasoactive-inotropic score after cardiac surgery: a substudy of a randomized clinical trial.

OBJECTIVE: Vasoactive medications improve hemodynamics after cardiac surgery but are associated with high metabolic and arrhythmic burdens. The vasoactive-inotropic score was developed to quantify vasoactive and inotropic support after cardiac surgery in pediatric patients but may be useful in adults as well. Accordingly, we examined the time course of this score in a substudy of the Biventricular Pacing After Cardiac Surgery trial. We hypothesized that the score would be lower in patients randomized to biventricular pacing. METHODS: Fifty patients selected for increased risk of left ventricular dysfunction after cardiac surgery and randomized to temporary biventricular pacing or standard of care (no pacing) after cardiopulmonary bypass were studied in a clinical trial between April 2007 and June 2011. Vasoactive agents were assessed after cardiopulmonary bypass, after sternal closure, and 0 to 7 hours after admission to the intensive care unit. RESULTS: Over the initial 3 collection points after cardiopulmonary bypass (mean duration, 131 minutes), the mean vasoactive-inotropic score decreased in the biventricular pacing group from 12.0 ± 1.5 to 10.5 ± 2.0 and increased in the standard of care group from 12.5 ± 1.9 to 15.5 ± 2.9. By using a linear mixed-effects model, the slopes of the time courses were significantly different (P = .02) and remained so for the first hour in the intensive care unit. However, the difference was no longer significant beyond this point (P = .26). CONCLUSIONS: The vasoactive-inotropic score decreases in patients undergoing temporary biventricular pacing in the early postoperative period. Future studies are required to assess the impact of this effect on arrhythmogenesis, morbidity, mortality, and hospital costs.

Multilevel cervical fusion and its effect on disc degeneration and osteophyte formation.

STUDY DESIGN: The effect of single and double cervical fusion on adjacent segments was investigated using a finite element model of the cervical spine. A healthy spine and a cervical spine with a single and double fusion at different levels were analyzed and evaluated. Disc degeneration and osteophyte formation at the endplates and joints can then be addressed. OBJECTIVES: To evaluate the biomechanical effects of cervical fusion on the cervical spine from C3-C7. The goal was to asses the increase of intervertebral disc and bone stress induced by cervical fusion, the effects of single versus double level fusion, and whether the level in which the fusion is performed, might affect the biomechanics of the spine. SUMMARY OF BACKGROUND DATA: Clinical studies have reported that 25% of fusion patients report further degenerative problems within 10 years of fusion. METHODS.: Four finite element models of single fusion at different levels were generated, as well as three additional models for the case of double fusion. The maximum von Mises stresses for anulus, nucleus, and endplates and the motion of the nonfused segments were obtained during lateral bending, flexion, axial torsion, and extension. Each case was compared with the normal cervical spine. RESULTS: Results showed stress increases of up to 96% in the anulus, nucleus, and endplates after fusion. Facet constraining prevents increases in stress during extension. The stresses at all levels tend to be larger for double than for single fusion. CONCLUSIONS: The results of this study quantify the significant increase in the level of stresses below and above the fused segments in the cervical spine. A sustained level of this stress can lead to further discs degeneration and osteophytes.