Myocardial dysfunction in pediatric septic shock

Management Changes After Echocardiography Are Associated With Improved Outcomes in Critically Ill Children

OBJECTIVES

To evaluate management changes and outcomes in critically ill children after formal echocardiography.

DESIGN

Retrospective cohort study between January 1, 2011, and December 31, 2020.

SETTING

Tertiary care children's hospital.

PATIENTS

Patients from 1 to 18 years who had formal echocardiography within 72 hours of ICU admission and who were intubated and on vasoactive infusions at the time of the study. Patients were stratified into two cardiac function groups: 1) near-normal cardiac function and 2) depressed cardiac function.

METHODS

Clinical variables were abstracted from the electronic medical record and placed in time sequence relative to echocardiography. Vasoactive and fluid management strategies in place before echocardiography were associated with markers of tissue perfusion and volume overload. Management changes after echocardiography were characterized and associated with outcomes.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Among patients eventually found to have depressed cardiac function, the use of vasoconstrictors was associated with worse lactate clearance and oxygen extraction ratio. Use of vasoconstrictors in this cohort was also associated with a more liberal fluid management strategy, evidence of increased lung water, and a worse Sp o2 /F io2 . An echocardiogram demonstrated depressed cardiac function was likely to be followed by management changes that favored inotropes and more conservative fluid administration. Patients with depressed cardiac function who were switched to inotropes were more likely to be extubated and to wean off vasoactive support compared with those patients who remained on vasoconstrictors.

CONCLUSIONS

Among patients with depressed cardiac function, alterations in management strategy after echocardiography are associated with shortened duration of intensive care interventions.

Use of Speckle-Tracking Echocardiography in Septic Cardiomyopathy in Critically Ill Children: A Narrative Review

OBJECTIVES

In critically ill children with severe sepsis, septic cardiomyopathy (SCM) denotes the subset of patients who have myocardial dysfunction with poor response to fluid and inotropic support, and higher mortality risk. The objective of this review was to evaluate the role of speckle-tracking echocardiography (STE) in the diagnosis and prognosis of pediatric SCM in the PICU setting.

DATA SOURCES

We performed detailed searches using PubMed, Scopus, Web of Science, and Google Scholar. Reference lists of all included studies were also examined for further identification of potentially relevant studies.

STUDY SELECTION

Studies with the following medical subject headings and keywords were selected: speckle-tracking echocardiography, strain imaging, global longitudinal strain, echocardiography, sepsis, severe sepsis, septic shock, septic cardiomyopathy, and myocardial dysfunction.

DATA EXTRACTION

The following data were extracted from all included studies: demographics, diagnoses, echocardiographic parameters, severity of illness, PICU management, and outcomes.

DATA SYNTHESIS

STE is a relatively new echocardiographic technique that directly quantifies myocardial contractility. It has high sensitivity in diagnosing SCM, correlates well with illness severity, and has good prognosticating value as compared with conventional echocardiographic parameters. Further studies are required to establish its role in evaluating biventricular systolic and diastolic dysfunction, and to investigate whether it has a role in individualizing treatment and improving treatment outcomes in this group of patients.

CONCLUSIONS

STE is a useful adjunct to conventional measures of cardiac function on 2D-echocardiography in the assessment of pediatric SCM in the PICU.

Assessment of hemodynamic dysfunction in septic newborns by functional echocardiography: a systematic review

BACKGROUND

Neonatal sepsis remains a leading cause of mortality in neonatal units. Neonatologist-performed echocardiography (NPE) offers the potential for early detection of sepsis-associated cardiovascular dysfunction. This review examines available echocardiographic findings in septic neonates.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically reviewed prospective observational, cross-sectional, case control, and cohort studies on septic newborns with echocardiographic assessments from PubMed, Scopus and Embase. Quality assessment employed the Newcastle-Ottawa Scale, with results analyzed descriptively.

RESULTS

From an initial pool of 1663 papers, 12 studies met inclusion criteria after relevance screening and eliminating duplicates/excluded studies. The review encompassed 438 septic newborns and 232 controls. Septic neonates exhibited either increased risk of pulmonary hypertension or left ventricular diastolic dysfunction, and a warm shock physiology characterized by higher cardiac outputs.

DISCUSSION

The included studies exhibited heterogeneity in sepsis definitions, sepsis severity scores, echocardiographic evaluations, and demographic data of newborns. Limited sample sizes compromised analytical interpretability. Nonetheless, this work establishes a foundation for future high-quality echocardiographic studies.

CONCLUSION

Our review confirms that septic neonates show significant hemodynamic changes that can be identified using NPE. These findings underscore the need for wider NPE use to tailor hemodynamics-based strategies within this population.

IMPACT

1. Our study emphasizes the value of neonatologist-performed echocardiography (NPE) as a feasible tool for identifying significant hemodynamic changes in septic neonates. 2. Our study underscores the importance of standardized echocardiographic protocols and frequent monitoring of cardiac function in septic neonates. 3. The impact of the study lies in its potential to increase researchers' awareness for the need for more high-quality echocardiographic data in future studies. By promoting wider use of NPE, neonatologists can more accurately assess the hemodynamic status of septic newborns and tailor treatment approaches, potentially improving patient outcomes.

Inhibition of Pyruvate Dehydrogenase Kinase 4 Attenuates Myocardial and Mitochondrial Injury in Sepsis-Induced Cardiomyopathy

BACKGROUND

Sepsis-induced cardiomyopathy (SIC) is a cardiac dysfunction caused by sepsis, with mitochondrial dysfunction being a critical contributor. Pyruvate dehydrogenase kinase 4 (PDK4) is a kinase of pyruvate dehydrogenase with multifaceted actions in mitochondrial metabolism. However, its role in SIC remains unknown.

METHODS

Serum PDK4 levels were measured and analyzed in 27 children with SIC, 30 children with sepsis, and 29 healthy children. In addition, for mice exhibiting SIC, the effects of PDK4 knockdown or inhibition on the function and structure of the myocardium and mitochondria were assessed.

RESULTS

The findings from the analysis of children with SIC revealed that PDK4 was significantly elevated and correlated with disease severity and organ injury. Nonsurvivors displayed higher serum PDK4 levels than survivors. Furthermore, mice with SIC benefited from PDK4 knockdown or inhibition, showing improved myocardial contractile function, reduced myocardial injury, and decreased mitochondrial structural injury and dysfunction. In addition, inhibition of PDK4 decreased the inhibitory phosphorylation of PDHE1α (pyruvate dehydrogenase complex E1 subunit α) and improved abnormal pyruvate metabolism and mitochondrial dysfunction.

CONCLUSIONS

PDK4 is a potential biomarker for the diagnosis and prognosis of SIC. In experimental SIC, PDK4 promoted mitochondrial dysfunction with increased phosphorylation of PDHE1α and abnormal pyruvate metabolism.

LA, Ghosh S, Reddy M. Sepsis-Induced Myocardial Dysfunction in Pediatric Septic Shock: Prevalence, Predictors, and Outcome-A Prospective Observational Study

There is a paucity of literature on the prevalence, predictors, prognostic markers, and outcomes of sepsis-induced myocardial dysfunction (SMD) in pediatric septic shock. The objectives of our study were to estimate the prevalence of SMD in pediatric septic shock by point-of-care functional echocardiography (POCFE) and to study the association of SMD with severity of illness, organ dysfunctions, and outcomes. This prospective, observational study was conducted over a period of 1 year (from July 2018 to July 2019) in a 12-bed, tertiary pediatric intensive care unit (PICU) of an academic and referral hospital in South India. Children presenting with septic shock were enrolled in the study. POCFE was done within 6 hours of PICU admission and patients were categorized as having SMD based on POCFE findings. The prevalence of SMD (left ventricle ± right ventricle) was 32% (32/100). More than half of the children (54.5%) died in SMD group, whereas only 7.5% died in non-SMD group ( p  < 0.001). SMD was associated with higher organ dysfunctions, worse patient outcomes, and was found to be an independent predictor of mortality. The median lactate levels were higher in SMD group (3.15 [2.7, 5] vs. 2 [1.3, 2.7], p  < 0.001) as compared with non-SMD group. We observed significantly lower median lactate clearance at 6 hours in SMD than non-SMD (30.0% [-14.44, 44.22] vs. 59.8% [45.83, 71.43], p  < 0.001). Lactate levels at 6 hours with a threshold of 2.4 mmol/L was a good predictor of SMD with sensitivity and specificity of 73 and 80%, respectively. SMD is not an uncommon entity in children with septic shock. SMD was associated with worse patient outcomes, organ dysfunction, and mortality. Serum lactate trends may predict SMD and can be used as prognosticate markers as well.

The effect of myocardial dysfunction on mortality in children with septic shock: a prospective observational study

Pediatric septic shock is defined as progressive multi-organ dysfunction and cardiovascular dysfunction accompanying sepsis. Studies showing myocardial dysfunction associated with pediatric septic shock are very limited. The aim of this study was to evaluate the relationship between myocardial functions calculated by echocardiography, disease severity, and clinical outcomes in children with septic shock. This observational prospective study was conducted in a pediatric intensive care at a university-affiliated tertiary hospital. The patients diagnosed with septic shock between January 2021 and February 2022 were included in the study. The study was conducted with 56 patients. The rate of myocardial dysfunction (systolic and/or diastolic dysfunction) was 50%. Of these, 39.3% (n = 22) had systolic dysfunction, 17.9% (n = 10) had diastolic dysfunction, and 8.9% (n = 5) had both systolic and diastolic dysfunction. PRISM III score (p = 0.004), VIS (p < 0.001), lactate (p = 0.002), CK-MB (p = 0.023), troponin (p = 0.038), EF (p = 0.004) EF z-score (p = 0.003), MAPSE z-score (p = 0.049), TAPSE (p = 0.010), TAPSE z-score (p = 0.003), and mitral valve E/e ´z-score (p = 0.028) were statistically significant difference with mortality. No significant difference was found for mortality with MAPSE (p = 0.090), mitral valve E/A (p = 0.624), and mitral valve E/A z-score (p = 0.327). EF z-score was found to be associated with 30-day mortality (OR = 0,681, 95% CI 0,480 to 0.991, p = 0,045). We found the TAPSE z-score to be the most significant parameter with 30-day mortality (OR = 0,690, 95% CI 0,489 to 0.998, p = 0,032).  Conclusion: We found left ventricular dysfunction associated factor with mortality. TAPSE showing right ventricular dysfunction was found to be the independent risk factor most associated with mortality. What is Known: • Studies showing myocardial dysfunction associated with pediatric septic shock are limited. • Little is known about the use of echocardiography in pediatric septic shock, and there are no specific guidelines for treatment and follow-up in pediatric patients. What is New: • Characteristics, echocardiographic measurements, and outcomes were comprehensively assessed in children with septic shock. • As a result of our analysis, we found that TAPSE, which is easily measured at the bedside, is the most critical parameter in relation to mortality. • We offer recommendations for its use in the follow-up of children with septic shock.

Updates in pediatric ultrasound

PURPOSE OF REVIEW

Point-of-care ultrasound (POCUS) has various diagnostic and therapeutic applications in the pediatric acute care setting that have an impact on clinical outcomes.

RECENT FINDINGS

POCUS can improve diagnostic efficiency and expedite management in pediatric patients who present to the emergency department with common complaints such as respiratory distress, abdominal pain, shock, and pain.

SUMMARY

Rapid advancements in POCUS have allowed it to become a powerful tool in pediatric care. As the clinical applications of ultrasound diversify, research is needed to evaluate impacts on healthcare outcomes, delivery, and costs.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

The Correlations of Human Atrial Natriuretic Peptide on Cardiac Function and Hemodynamics in Pediatric Septic Shock

Purpose

We aimed to determine the correlations of human Atrial Natriuretic Peptide (ANP) on cardiac function and hemodynamics in pediatric septic shock.

Patients and Methods

We conducted an observational and prospective study on 30 children with septic shock. Measurement of the level of human atrial natriuretic peptide was determined in the serum of patients. Cardiac power (CP) is a cardiac function parameter measured with cardiac output (cardiovascular flow) and mean arterial (intravascular) pressure. Cardiac output and mean arterial pressure were monitored using pressure recording analytical methods (PRAM). Hemodynamic status was represented by a vasoactive inotropic score.

Results

Thirty pediatric septic shock patients fulfilled the eligibility criteria. The human ANP level was not significantly different in pediatric septic shock on three days of examination. Cardiac power was significantly different in pediatric septic shock on three days of examination. There was a correlation between human ANP and cardiac power on day 3 and human ANP and VIS on day 2.

Conclusion

There was a significant correlation between human ANP level and cardiac power on day 3 and ANP level and VIS on day 2. The cardiac power on day 3 and VIS on 48 hours can be alternatives to evaluate the hemodynamic status and cardiac function concerning human ANP in pediatric septic shock.

Prevalence of Cardiac Dysfunction in Malawian Children With Severe Febrile Illness

OBJECTIVES

To investigate the prevalence of left ventricular systolic dysfunction (LVSD) in Malawian children with severe febrile illness and to explore associations between LVSD and mortality and lactate levels.

DESIGN

Prospective observational study.

SETTING

Pediatric ward of a tertiary government referral hospital in Malawi.

PATIENTS

Children between 60 days and 10 years old with severe febrile illness (fever with at least one sign of impaired perfusion plus altered mentation or respiratory distress) were enrolled at admission from October 2017 to February 2018.

INTERVENTIONS

Focused cardiac ultrasound (FoCUS) was performed, and serum lactate was measured for each child at enrollment, with repeat FoCUS the following day. LV systolic function was later categorized as normal, reduced, severely reduced, or hyperdynamic by two pediatric cardiologists blinded to clinical course and outcomes.

MEASUREMENTS AND MAIN RESULTS

Fifty-four children were enrolled. LVSD was present in 14 children (25.9%; 95% CI, 15.4-40.3%), of whom three had severely reduced function. Thirty patients (60%) had a lactate greater than 2.5 mmol/L, of which 20 (40%) were markedly elevated (>5 mmol/L). Ten children died during admission (18.5%). Of children who survived, 22.7% had decreased LV systolic function versus 40% of those who died. Dysfunction was not associated with mortality or elevated lactate.

CONCLUSIONS

Cardiac dysfunction may be present in one in four Malawian children with severe febrile illness, and mortality in these patients is especially high. Larger studies are needed to further clarify the role cardiac dysfunction plays in mortality and integrate practical bedside assessments for decision support around individualized resuscitation strategies.

Integrated insights into the mechanisms underlying sepsis-induced myocardial depression using a quantitative global proteomic analysis

Sepsis-induced myocardial depression is common among patients in the intensive care unit; however, the exact mechanisms underlying this condition remain unclear. We investigated differences in the expression of specific proteins and determined the potential functions of the proteins in a rat model of lipopolysaccharide-induced septic shock. Left ventricular tissue was excised from 16 rats (sepsis group, 8; control group, 8) and analysed. Quantitative analysis of the global proteome was performed using 4D label-free technique. Bioinformatic analyses were conducted based on differentially expressed (DE) proteins. Parallel reaction monitoring (PRM) validation for selected proteins and western blotting for selected global protein modifications in heart tissues were also performed. As a result, out of 3653 proteins identified, 108 were expressed differentially between the two groups. The bioinformatic analyses revealed that DE proteins play important roles in metabolism- and immune-related pathways. PRM results supported the plausibility and reliability of the proteomics data. Modification of heart tissue acetyllysine, succinyllysine, 2-hydroxyisobutyryllysine, and lactyllysine revealed clear differences between the two groups, indicating the effects of protein modification. Our study suggested that expression patterns of global proteins in heart tissue were different between the two groups. These results provide new valuable information on the possible mechanisms underlying sepsis-induced myocardial depression. SIGNIFICANCE: The expression patterns of global proteins in the heart tissues of patients with sepsis and control groups remain unknown. In this study, we used the 4D label-free proteomics technique to compare differentially expressed (DE) proteins between the sepsis and control groups. We identified 3653 proteins, 108 of which were expressed differentially between the sepsis and control groups. Further bioinformatic analyses revealed that DE proteins play critical roles in metabolism- and immune-related processes and pathways. Interestingly, modification of heart tissue acetyllysine, succinyllysine, 2-hydroxyisobutyryllysine, and lactyllysine revealed clear differences between the sepsis and control groups. The findings of this study improve our understanding of the basic molecular mechanisms underlying sepsis-induced myocardial depression.

Characteristics of hemodynamic parameters after fluid resuscitation and vasoactive drugs administration in pediatric shock: A prospective observational study

Background

Prior studies have shown that septic shock survivors had a normal cardiac index (CI) and systemic vascular resistance index (SVRI). However, this feature seems to be questionable in other-caused shock, since several factors are associated with the hemodynamic profile. This study aims to describe hemodynamic profiles (preload, inotropy, afterload, stroke volume, and cardiac output) after fluid resuscitation and vasoactive therapy in children with shock.

Methods

Children aged 1 month to 18 years old with shock conditions were included in this study. Fluid resuscitation was administered following the American College of Critical Care Medicine (ACCM) protocol. Hemodynamic profiles were assessed at 1 and 6 h from the start of fluid resuscitation. Grouping of the subjects was determined by the USCOM examination in 1st hour until the end of the study and we divided into 3 groups.

Results

At 1 h, group 1 (low CI) was 14% (CI:2.5[1.2–3.2]L/min/m²), group 2 (normal CI) was 66% (CI:4.2[3.4–5.8]L/min/m²), and group 3 (high CI) was 20% (CI:7.1[6.1–9.4]L/min/m²). SVRI was higher in groups 1 and 2 compared to group 3 (p < 0.05). Group 1 and 2 revealed fluid-refractory shock (SVV:25[12–34]% and 29(13–58)%, respectively), lower Smith-Madigan Inotropy Index (SMII) and higher Potential to Kinetic Ratio (PKR) compared to group 3 (p < 0.05). Group 3 revealed fluid-responsive shock (Stroke Volume Variation (SVV):32[18–158]%), higher SMII and lower PKR. At 6th hour, CI in all groups were normal (group 1:3.5[1.2–7.5]; group 2:4.0[1.7–6.1]; group 3:6.0[3.1–6.2]). However, 71.4% and 54.5% of subjects in groups 1 and 2, respectively, still revealed low inotropy. Group 3 revealed a significant increase in SVRI and PKR (p < 0.01).

Conclusions

Most pediatric shock patients were hypodynamic. Even when the CI was normal, the preload, inotropy, and afterload may still be abnormal. It represented the inotropy as a key to hemodynamic.

•

Describe the macrocirculation parameter (preload, inotropy, afterload) in children with shock.

•

Most pediatric shock tend to be hypodynamic.

•

Fluid and vasoactive agent therapy should be guided by combination of the hemodynamic parameters.

High-sensitivity cardiac troponins in pediatric population

Apparently healthy children often complain of chest pain, especially after physical exercise. Cardiac biomarker levels are often measured, but the clinical relevance of these assays in children is still debated, even when a cardiac disease is present. Coronary artery disease is exceedingly rare in children, but elevated circulating levels of cardiac troponin I (cTnI) and T (cTnT) in an acute setting may help detect heart failure due to an unknown cardiac disorder, or worsening heart failure, particularly in combination with other biomarkers such as B-type natriuretic peptides. However, the interpretation of biomarkers is often challenging, especially when institutions transition from conventional cTn assays to high-sensitivity (hs-cTn) methods, as well demonstrated in the emergency setting for adult patients. From a clinical perspective, the lack of established reference values in the pediatric age is the main problem limiting the use of hs-cTn methods for the diagnosis and managements of cardiac diseases in infants, children and adolescents. This review aims to discuss the possibility to use hs-cTnI and hs-cTnT to detect cardiac disease and to explore age-related differences in biomarker levels in the pediatric age. We start from some analytical and pathophysiological considerations related to hs-cTn assays. Then, after a systematic literature search, we discuss the current evidence and possible limitations of hs-cTn assay as indicators of cardiac disease in the most frequently cardiac disease in pediatric setting.

Application of B-Type Natriuretic Peptide in Neonatal Diseases

Numerous congenital or secondary diseases, including, heart disease, respiratory disease, sepsis and many others, can lead to neonatal death. B-type natriuretic peptide (BNP) is a peptide hormone secreted by ventricular cells following an increase in ventricular wall tension. BNP functions to promote vasodilation, diuresis, and sodium release to regulate blood pressure. BNP is a sensitive index reflecting ventricular function, which may aid the diagnosis and monitoring of various neonatal diseases. In neonates, there is currently no consensus on a reference BNP level, as the plasma BNP concentration of healthy newborns varies with age, peaks in the first week after birth, and then gradually decreased to a stable level. In disease states, the correlation between the plasma BNP concentration and the results of echocardiography is good, which is of great significance in the screening, monitoring, and prognosis evaluation of neonatal cardiovascular diseases, including congenital heart disease, patent ductus arteriosus, etcetera. It also facilitates the judgment of the efficacy of treatment and perioperative management. Moreover, the monitoring of plasma BNP concentration provides guidance for the diagnosis, evaluation, and treatment selection of certain neonatal respiratory diseases and neonatal sepsis. This review summarizes the normal BNP values and discusses the application value of BNP in relation to physiological and pathological aspects in neonates.

Role of non-coding RNAs as biomarkers of deleterious cardiovascular effects in sepsis

The mechanisms occurring during sepsis that produce an increased risk of cardiovascular (CV) disease (CVD) are poorly understood. Even less information exists regarding CV dysfunction as a complication of sepsis, particularly for sepsis-induced cardiomyopathy. However, recent research has demonstrated that non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, play a crucial role in genetic reprogramming, gene regulation, and inflammation during the development of CVD. Here we describe experimental findings showing the importance of non-coding RNAs mediating relevant mechanisms underlying CV dysfunction after sepsis, so contributing to sepsis-induced cardiomyopathy. Importantly, non-coding RNAs are critical novel regulators of CVD risk factors. Thus, they are potential candidates to improve diagnostics and prognosis of sepsis-induced cardiomyopathy and other CVD events occurring after sepsis and set the basis to design novel therapeutic strategies.

Cardiac Biomarkers in Pediatrics: An Undervalued Resource

BACKGROUND

The clinical use of common cardiac biomarkers, such as brain natriuretic peptides and troponins, has traditionally been limited to adult populations in the assessment of heart failure and acute coronary syndrome, respectively. While many have discounted the value of these markers in pediatric populations, emerging evidence suggests they may be useful in the diagnosis and prognostication of many cardiac and noncardiac pathologies in neonates, children, and adolescents, and an increasing number of pediatric hospitals are routinely measuring cardiac markers in their clinical practice.

CONTENT

This review summarizes and critically evaluates the current literature regarding the application of cardiac biomarkers for clinical decision-making in the pediatric population. Main potential clinical indications discussed herein include primary cardiac disease, immune-related conditions, and noncardiac disease. Important diagnostic and interpretative challenges are also described in relation to each potential indication.

SUMMARY

Despite a general lack of clinical awareness regarding the value of cardiac biomarkers in pediatrics, there is increasing literature to support their application in various contexts. Cardiac biomarkers should be considered an undervalued resource in the pediatric population with potential value in the diagnosis and prognosis of myocarditis, congenital heart disease, and heart failure, as well as in the assessment of severity and cardiac involvement in immune-related and other systemic conditions. While interpretation remains challenging in pediatrics due to the age- and sex-specific dynamics occurring throughout growth and development, this should not prevent their application. Future research should focus on defining evidence-based cut-offs for specific indications using the most up-to-date assays.

Comparative transcriptome analysis of transcripts of uncertain coding potential in septic myocardial depression

BACKGROUND

Septic shock with myocardial depression is very common in intensive care units. However, the exact molecular mechanisms underlying sepsis-induced myocardial depression remain unclear. Whether the profiles of transcripts of uncertain coding potential (TUCPs) differ between patients with and without myocardial depression is also unknown. Our study aimed to find expression differences between groups of TUCPs and determine their potential functions in a preclinical model.

METHODS

We generated rat models of hypodynamic septic shock induced by lipopolysaccharide. A total of 12 rats were established and left ventricular tissue from each was collected. We performed RNA-seq to identify TUCPs in each sample. Transcripts with an corrected P value of < 0.05 were defined as differentially expressed (DE). We also performed GO terms and KEGG analysis to identify the potential functions of DE TUCPs.

RESULTS

A total of 4,851 TUCPs were identified in heart samples, 85 of which were expressed differently between the sepsis and control groups. Further bioinformatic analyses suggested that TUCPs play important roles in myocardial contraction, energy regulation, and metabolic processes, and are also involved in the regulation of several pathways.

CONCLUSION

Our results demonstrate that TUCPs both participate in and mediate the pathological process of myocardial depression. Our study improves the understanding of the basic molecular mechanisms underlying myocardial depression from a novel perspective.

Integrating Focused Cardiac Ultrasound Into Pediatric Septic Shock Assessment

OBJECTIVES

To assess focused cardiac ultrasound impact on clinician hemodynamic characterization of patients with suspected septic shock as well as expert-generated focused cardiac ultrasound algorithm performance.

DESIGN

Retrospective, observational study.

SETTING

Single-center, noncardiac PICU.

PATIENTS

Less than 18 years old receiving focused cardiac ultrasound study within 72 hours of sepsis pathway initiation from January 2014 to December 2016.

INTERVENTIONS

Hemodynamics of patients with suspected septic shock were characterized as fluid responsive, myocardial dysfunction, obstructive physiology, and/or reduced systemic vascular resistance by a bedside clinician before and immediately following focused cardiac ultrasound performance. The clinician's post-focused cardiac ultrasound hemodynamic assessments were compared with an expert-derived focused cardiac ultrasound algorithmic hemodynamic interpretation. Subsequent clinical management was assessed for alignment with focused cardiac ultrasound characterization and association with patient outcomes.

MEASUREMENTS AND MAIN RESULTS

Seventy-one patients with suspected septic shock (median, 4.7 yr; interquartile range, 1.6-8.1) received clinician performed focused cardiac ultrasound study within 72 hours of sepsis pathway initiation (median, 2.1 hr; interquartile range, -1.5 to 11.8 hr). Two patients did not have pre-focused cardiac ultrasound and 23 patients did not have post-focused cardiac ultrasound hemodynamic characterization by clinicians resulting in exclusion from related analyses. Post-focused cardiac ultrasound clinician hemodynamic characterization differed from pre-focused cardiac ultrasound characterization in 67% of patients (31/46). There was substantial concordance between clinician's post-focused cardiac ultrasound and algorithm hemodynamic characterization (33/48; κ = 0.66; CI, 0.51-0.80). Fluid responsive (κ = 0.62; CI, 0.40-0.84), obstructive physiology (к = 0.87; CI, 0.64-1.00), and myocardial dysfunction (1.00; CI, 1.00-1.00) demonstrated substantial to perfect concordance. Management within 4 hours of focused cardiac ultrasound aligned with algorithm characterization in 53 of 71 patients (75%). Patients with aligned management were less likely to have a complicated course (14/52, 27%) compared with misaligned management (8/19, 42%; p = 0.25).

CONCLUSIONS

Incorporation of focused cardiac ultrasound in the evaluation of patients with suspected septic shock frequently changed a clinician's characterization of hemodynamics. An expert-developed algorithm had substantial concordance with a clinician's post-focused cardiac ultrasound hemodynamic characterization. Management aligned with algorithm characterization may improve outcomes in children with suspected septic shock.

Echocardiographic Parameters and Mortality in Pediatric Sepsis: A Systematic Review and Meta-Analysis

OBJECTIVE

We conducted a systematic review and meta-analysis to investigate the prognostic value of echocardiographic parameters in pediatric septic patients.

DATA SOURCES

MEDLINE, PubMed, and EMBASE (last update April 5, 2020).

STUDY SELECTION

Observational studies of pediatric sepsis providing echocardiographic parameters in relation to mortality.

DATA EXTRACTION

Echocardiography data were categorized as those describing left ventricular systolic or diastolic function, right ventricular function, and strain echocardiography parameters. Data from neonates and children were considered separately. Analysis is reported as standardized mean difference and 95% CI.

DATA SYNTHESIS

We included data from 14 articles (n = 5 neonates, n = 9 children). The fractional shortening was the most commonly reported variable (11 studies, n = 555 patients) and we did not identify an association with mortality (standardized mean difference 0.22, 95% CI [-0.02 to 0.47]; p = 0.07, I2 = 28%). In addition, we did not find any association with mortality also for left ventricular ejection fraction (nine studies, n = 417; standardized mean difference 0.06, 95% CI [-0.27 to 0.40]; p = 0.72, I2 = 51%), peak velocity of systolic mitral annular motion determined by tissue Doppler imaging wave (four studies, n = 178; standardized mean difference -0.01, 95% CI [-0.34 to 0.33]; p = 0.97, I2 = 0%), and myocardial performance index (five studies, n = 219; standardized mean difference -0.51, 95% CI [-1.10 to 0.08]; p = 0.09, I2 = 63%). However, in regard to left ventricular diastolic function, there was an association with mortality for higher early wave of transmitral flow/peak velocity of early diastolic mitral annular motion determined by tissue Doppler imaging ratio (four studies, n = 189, standardized mean difference -0.45, 95% CI [-0.80 to -0.10]; p = 0.01, I2 = 0%) or lower peak velocity of early diastolic mitral annular motion determined by tissue Doppler imaging wave (three studies, n = 159; standardized mean difference 0.49, 95% CI [0.13-0.85]; p = 0.008, I2 = 0%). We did not find any association with mortality for early wave of transmitral flow/late (atrial) wave of trans-mitral flow ratio (six studies, n = 273; standardized mean difference 0.28, 95% CI [-0.42 to 0.99]; p = 0.43, I2 = 81%) and peak velocity of systolic mitral annular motion determined by tissue Doppler imaging wave measured at the tricuspid annulus (three studies, n = 148; standardized mean difference -0.18, 95% CI [-0.53 to 0.17]; p = 0.32, I2 = 0%). Only a few studies were conducted with strain echocardiography.

CONCLUSIONS

This meta-analysis of echocardiography parameters in pediatric sepsis failed to find any association between the measures of left ventricular systolic or right ventricular function and mortality. However, mortality was associated with higher early wave of transmitral flow/peak velocity of early diastolic mitral annular motion determined by tissue Doppler imaging or lower peak velocity of early diastolic mitral annular motion determined by tissue Doppler imaging, indicating possible importance of left ventricular diastolic dysfunction. These are preliminary findings because of high clinical heterogeneity in the studies to date.

Point of care ultrasound in the paediatric acute care setting: Getting to the 'heart' of respiratory distress

Point-of-care ultrasound (POCUS) is a growing interesting tool in the emergency setting. Its usefulness in diagnostic and therapeutic pathway of patients with respiratory distress in addition to clinical evaluation is well established in adult emergency medicine while paediatric specific data, although growing, remain limited. We report a case series of paediatric patients presenting with respiratory distress successfully diagnosed with cardiac dysfunction following POCUS evaluations. Lung POCUS, in combination with cardiac POCUS, is a very useful supplementary diagnostic tool to assess the breathless child and to rapidly identify life-threatening primary etiologies or secondary physiologies. Thus, fast echocardiography is a desirable aid for paediatric emergency physicians and should be supported in all paediatric emergency settings following an adequate training that is mandatory regarding image acquisition and data interpretation.

Left Ventricular Diastolic Dysfunction in Pediatric Sepsis: Outcomes in a Single-Center Retrospective Cohort Study

OBJECTIVES

Left ventricular diastolic dysfunction is associated with difficulty in ventilator weaning and increased mortality in septic adults. We evaluated the association of left ventricular diastolic dysfunction with outcomes in a cohort of children with severe sepsis and septic shock.

DESIGN

Retrospective cohort study.

SETTING

Single-center noncardiac PICU.

PATIENTS

Age greater than 1 month to less than 18 years old with severe sepsis or septic shock from January 2011 to June 2017 with echocardiogram within 48 hours of sepsis onset.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Echocardiograms were retrospectively assessed for mitral inflow E (early) and A (atrial) velocity and e' (early mitral annular motion) septal and lateral velocity. Left ventricular diastolic dysfunction was defined as E/e' greater than 10, E/A less than 0.8, or E/A greater than 1.5. Left ventricular diastolic dysfunction was present in 109 of 204 patients (53%). The data did not demonstrate an association between the presence of left ventricular diastolic dysfunction and the proportion of children requiring invasive mechanical ventilation at the time of echocardiogram (difference in proportion, +5% [72% vs 67%; 95% CI, -8% to 17%]; p = 0.52). The duration of mechanical ventilation was median 192.9 hours (interquartile range, 65.0-378.4 hr) in the left ventricular diastolic dysfunction group versus 151.0 hours (interquartile range, 45.7-244.3 hr) in the group without left ventricular diastolic dysfunction. The presence of left ventricular diastolic dysfunction was not significantly associated with ICU length of stay or mortality. Exploratory analyses revealed that an alternative definition of left ventricular diastolic dysfunction, solely defined by E/e' greater than 10, was found to have an association with mechanical ventilation requirement at the time of echocardiogram (difference in proportion, +15%; 95% CI, 3-28%; p = 0.02) and duration of mechanical ventilation (median, 207.3 vs 146.9 hr).

CONCLUSIONS

The data failed to show an association between the presence of left ventricular diastolic dysfunction defined by both E/e' and E/A and the primary and secondary outcomes. When an alternative definition of left ventricular diastolic dysfunction with E/e' alone was used, there was a significant association with respiratory outcomes.

Validation of the pediatric refractory septic shock definition: post hoc analysis of a controlled trial

Background

The European Society of Pediatric and Neonatal Intensive Care (ESPNIC) developed and validated a definition of pediatric refractory septic shock (RSS), based on two septic shock scores (SSS). Both bedside SSS (bSSS) and computed SSS (cSSS) were found to be strongly associated with mortality. We aimed at assessing the accuracy of the RSS definition on a prospective cohort from India.

Methods

Post hoc analysis of a cohort issued from a double-blind randomized trial that compared first-line vasoactive drugs in children with septic shock. Sequential bSSS and cSSS from 60 children (single-center study, 53% mortality) were analyzed. The prognostic value of the ESPNIC RSS definition was tested for 28-day all-cause mortality.

Results

In this septic shock cohort, RSS was diagnosed in 35 patients (58.3%) during the first 24 h. Death occurred in 30 RSS patients (85.7% mortality) and in 2 non-RSS patients (8% mortality), OR = 60.9 [95% CI: 10.5–676.2], p < 0.001 with a median delay from sepsis onset of 3 days [1.0–6.7]. Among patients diagnosed with RSS, the mortality was not significantly different according to vasopressors randomization. Diagnosis of RSS with bSSS and cSSS had a high discrimination for death with an area under the receiver operating curve of 0.916 [95% CI: 0.843–0.990] and 0.925 [95% CI: 0.845–1.000], respectively. High prognostic accuracy of the bSSS was found in the first hours following intensive care admission. The best interval of prognostication occurs after the 12th hour following treatment initiation (AUC 0.973 [95% CI: 0.925–1.000]).

Conclusions

The ESPNIC refractory septic shock definition accurately identifies, within the first 6 h of septic shock management, children with lethal outcome.

Assessment of left-ventricular diastolic function in pediatric intensive-care patients: a review of parameters and indications compared with those for adults

BACKGROUND

The incidence of diastolic heart failure has increased over time. The evaluation of left-ventricular diastolic function is complex, ongoing, and remains poorly performed in pediatric intensive-care patients. This study aimed to review the literature and to provide an update on the evaluation of left-ventricular diastolic function in adults and children in intensive care.

DATA SOURCES

We searched data from PubMed/Medline. Thirty-two studies were included. Four pragmatic questions were identified: (1) What is the physiopathology of diastolic dysfunction? (2) Which tools are required to evaluate diastolic function? (3) What are the echocardiographic criteria needed to evaluate diastolic function? (4) When should diastolic function be evaluated in pediatric intensive care?

RESULTS

Early diastole allows characterization of relaxation, whereas compliance assessments and filling pressures are evaluated during late diastole. The evolution of diastolic function differs between adults and children. Unlike in adults, decreased compliance occurs at the same time as delayed relaxation in children. Diastolic function can be evaluated by Doppler echocardiography. The echocardiographic criteria for ventricular relaxation include the E wave, E/A wave ratio, and isovolumic relaxation time. Ventricular compliance can be assessed by the E/e' wave ratio, atrial volume, and Ap wave duration during pulmonary vein flow. In adult intensive-care patients, the E/e' ratio can be used as an index of tolerance for volume expansion in septic patients and to adjust the inotropic support.

CONCLUSION

Clinical studies would allow some of these parameters to be validated for use in children in intensive care.

Recognition and management of neonatal hemodynamic compromise

Hemodynamic compromise of the neonate can occur in various clinical situations, including but not limited to maladaptation during the early transitional period, sepsis, congenital heart anomalies, hemodynamically significant patent ductus arteriosus, persistent pulmonary hypertension of the newborn, systemic inflammatory diseases such as necrotizing enterocolitis, and dehydration. Despite the handful of advances in neonatal care through ground-breaking clinical trials, the management of neonatal shock is often dependent on the bedside clinician's experience and training without the aid of high-level evidence. However, the recognition for the importance of comprehensive and serial hemodynamic assessment is growing. There is now a wealth of literature investigating the use of functional echocardiography, near-infrared spectroscopy, and noninvasive impedance-based cardiometry to complement common bedside hemodynamic measures such as blood pressure and heart rate measurement. In this review article, the pathophysiology of neonatal hemodynamic compromise is outlined, and concomitant best-evidence management for hemodynamic compromise in the neonate is proposed.

Characterization of Circular RNA and microRNA Profiles in Septic Myocardial Depression: a Lipopolysaccharide-Induced Rat Septic Shock Model

Septic shock with heart dysfunction is common in intensive care units. However, the mechanism underlying myocardial depression is still unclear. Whether circular RNA (circRNA) or microRNA (miRNA) profiles differ between patients with and without myocardial depression is unknown. We generated a hypodynamic septic shock model induced by lipopolysaccharide (LPS) in adolescent rats. A total of 12 rats were utilized and heart tissue from each was collected. RNA sequencing was performed on left ventricular tissue. We focused on features of circRNAs and miRNAs, predicting their function by bioinformatic analysis and constructing circRNA-associated and miRNA-associated regulatory networks in heart tissue. We detected 851 circRNAs in heart samples, and 11 showed differential expression. A total of 639 annotated miRNAs and 91 novel miRNAs were explored including 78 showing differential expression between the two groups. We then constructed the most comprehensive circRNA-associated and miRNA-associated networks to explore their regulatory relationship in septic heart tissue, and demonstrated that different networks could potentially participate in and regulate the pathological process of sepsis. Furthermore, gene ontology term enrichment indicated miRNAs, and miRNA-mRNA networks could be associated with regulation and metabolic process, or influence cellular functions. The construction of regulator networks could improve the understanding of the basic molecular mechanisms underlying myocardial depression. It will be important for future investigations to ascertain the biological mechanisms present during the development of sepsis-induced myocardial depression to influence approaches to treatment.

Longitudinal Study of CPK-MB and Echocardiographic Measures of Myocardial Dysfunction in Pediatric Sepsis: Are Patients with Shock Different from Those without?

Background

Sepsis-induced myocardial dysfunction has implications on outcome. For lack of echocardiography in resource-limited settings, myocardial biomarkers may be an alternative monitoring tool.

Objective

This study was planned to explore the longitudinal behavior of creatine phosphokinase-MB (CPK-MB) in children with sepsis with and without shock, and its correlation with clinical and echocardiographic parameters over the first 10 days.

Design

Prospective observational study.

Setting

Tertiary care hospital in a lower-middle-income economy of South Asia.

Patients

Children (3 months to 12 years) with nonshock sepsis (NSS) (n = 40) and septic shock survivors (SSSs) (n = 40) after optimal resuscitation. Patients with catecholamine refractory shock, preexisting heart disease, and cardiorespiratory event within the past 1 month were excluded from the study.

Measurements and main results

Pediatric logistic organ dysfunction (PeLOD) score, vasoactive inotrope score (VIS), CPK-MB, and echocardiographic measures of myocardial function were recorded on days 1, 3, 7, and 10. Echocardiography was repeated at 1 month. Both groups were similar at baseline. The SSSs had higher CPK-MB (180 vs 53 IU/L; p < 0.001) and PeLOD score (2 ± 0.4 vs 11.7 ± 5.1, p < 0.001) on day 1 compared to the NSS children. More than half of the SSS and none of the NSS patients had myocardial dysfunction. Reduction in CPK-MB over 10 days correlated well with improvement in PeLOD (p < 0.01), VIS (p = 0.04), and echocardiographic measures of myocardial dysfunction (p < 0.05) among SSSs. At 1 month follow-up, all had normal echocardiography.

Conclusion

The SSSs had markedly elevated CPK-MB, and its fall paralleled the improvement in clinical status and myocardial dysfunctions. The CPK-MB could be a potential monitoring tool for septic cardiomyopathy in resource-limited settings.

How to cite this article

Baranwal AK, Deepthi G, Rohit MK, Jayashree M, Angurana SK, Kumar-M P. Longitudinal Study of CPK-MB and Echocardiographic Measures of Myocardial Dysfunction in Pediatric Sepsis: Are Patients with Shock Different from Those without? Indian J Crit Care Med 2020;24(2):109–115.

Characterization of Long Noncoding RNA and mRNA Profiles in Sepsis-Induced Myocardial Depression

Septic shock with heart dysfunction is very common in intensive care units. However, whether long noncoding RNA (lncRNA) and mRNA profiles differ between patients with and without myocardial depression is unknown. We generated rat models of hypodynamic septic shock induced by lipopolysaccharide. A total of 12 rat models was constructed and heart tissue from each was collected. Whole genomic RNA sequencing was performed on left ventricular tissue; 6,508 novel lncRNAs and 432 annotated lncRNAs were identified in heart samples, and 74 lncRNAs were expressed differently in the sepsis and control groups. Gene ontology term enrichment indicated apoptosis and its related pathways showed obvious enrichment, which suggested cell apoptosis could play a critical role in the process of myocardial depression. Furthermore, we focused on one lncRNA from the Pvt1 gene. By silencing this lncRNA, we demonstrated knockdown of Pvt1 expression could induce cell apoptosis in lipopolysaccharide-induced heart cells, through increasing the expression of c-Myc, Bid, Bax, and caspase-3 and decreasing the expression of Myd88 and Bcl-2, thereby proving its functional role in myocardial depression. These results demonstrate that lncRNAs both participate in and mediate the pathological process of myocardial depression. Our study improves the understanding of the basic molecular mechanisms underlying myocardial depression.

Age-Dependent Myocardial Dysfunction in Critically Ill Patients: Role of Mitochondrial Dysfunction

Myocardial dysfunction is common in septic shock and post-cardiac arrest but manifests differently in pediatric and adult patients. By conventional echocardiographic parameters, biventricular systolic dysfunction is more prevalent in children with septic shock, though strain imaging reveals that myocardial injury may be more common in adults than previously thought. In contrast, diastolic dysfunction in general and post-arrest myocardial systolic dysfunction appear to be more widespread in the adult population. A growing body of evidence suggests that mitochondrial dysfunction mediates myocardial depression in critical illness; alterations in mitochondrial electron transport system function, bioenergetic production, oxidative and nitrosative stress, uncoupling, mitochondrial permeability transition, fusion, fission, biogenesis, and autophagy all may play key pathophysiologic roles. In this review we summarize the epidemiologic and clinical phenotypes of myocardial dysfunction in septic shock and post-cardiac arrest and the multifaceted manifestations of mitochondrial injury in these disease processes. Since neonatal and pediatric-specific data for mitochondrial dysfunction remain sparse, conclusive age-dependent differences are not clear; instead, we highlight what evidence exists and identify gaps in knowledge to guide future research. Finally, since focal ischemic injury (with or without reperfusion) leading to myocardial infarction is predominantly an atherosclerotic disease of the elderly, this review focuses specifically on septic shock and global ischemia-reperfusion injury occurring after resuscitation from cardiac arrest.

Global Case-Fatality Rates in Pediatric Severe Sepsis and Septic Shock: A Systematic Review and Meta-analysis

IMPORTANCE

The global patterns and distribution of case-fatality rates (CFRs) in pediatric severe sepsis and septic shock remain poorly described.

OBJECTIVE

We performed a systematic review and meta-analysis of studies of children with severe sepsis and septic shock to elucidate the patterns of CFRs in developing and developed countries over time. We also described factors associated with CFRs.

DATA SOURCES

We searched PubMed, Web of Science, Excerpta Medica database, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Cochrane Central systematically for randomized clinical trials and prospective observational studies from earliest publication until January 2017, using the keywords "pediatric," "sepsis," "septic shock," and "mortality."

STUDY SELECTION

Studies involving children with severe sepsis and septic shock that reported CFRs were included. Retrospective studies and studies including only neonates were excluded.

DATA EXTRACTION AND SYNTHESIS

We conducted our systematic review and meta-analysis in close accordance to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pooled case-fatality estimates were obtained using random-effects meta-analysis. The associations of study period, study design, sepsis severity, age, and continents in which studies occurred were assessed with meta-regression.

MAIN OUTCOMES AND MEASURES

Meta-analyses to provide pooled estimates of CFR of pediatric severe sepsis and septic shock over time.

RESULTS

Ninety-four studies that included 7561 patients were included. Pooled CFRs were higher in developing countries (31.7% [95% CI, 27.3%-36.4%]) than in developed countries (19.3% [95% CI, 16.4%-22.7%]; P < .001). Meta-analysis of CFRs also showed significant heterogeneity across studies. Continents that include mainly developing countries reported higher CFRs (adjusted odds ratios: Africa, 7.89 [95% CI, 6.02-10.32]; P < .001; Asia, 3.81 [95% CI, 3.60-4.03]; P < .001; South America, 2.91 [95% CI, 2.71-3.12]; P < .001) than North America. Septic shock was associated with higher CFRs than severe sepsis (adjusted odds ratios, 1.47 [95% CI, 1.41-1.54]). Younger age was also a risk factor (adjusted odds ratio, 0.95 [95% CI, 0.94-0.96] per year of increase in age). Earlier study eras were associated with higher CFRs (adjusted odds ratios for 1991-2000, 1.24 [95% CI, 1.13-1.37]; P < .001) compared with 2011 to 2016. Time-trend analysis showed higher CFRs over time in developing countries than developed countries.

CONCLUSIONS AND RELEVANCE

Despite the declining trend of pediatric severe sepsis and septic shock CFRs, the disparity between developing and developed countries persists. Further characterizations of vulnerable populations and collaborations between developed and developing countries are warranted to reduce the burden of pediatric sepsis globally.

The prognostic value of left ventricular systolic function and cardiac biomarkers in pediatric severe sepsis

Echocardiography and cardiac biomarkers, such as cardiac troponin I (cTnI) and N-terminal pro-B-type natriuretic peptide (NT-pro BNP) are useful tools to evaluate cardiac dysfunction. Left ventricular systolic dysfunction (LVSD) is common in pediatric severe sepsis. The aim of this study is to evaluate the prognostic value of LVSD, cTnI, and NT-pro BNP for pediatric severe sepsis.A prospective, single center, observational study was conducted. Severe sepsis children were enrolled in the study from December 2015 to December 2016 in pediatric intensive care unit of Shanghai Children's Medical Center. Recorded general information, transthoracic echocardiography were performed at day 1, 2, 3, 7, and 10, using Simpson to measure left ventricular end-diastolic dimension and left ventricular end-systolic dimension, obtained echocardiography parameters: left ventricular ejection fraction (LVEF), left ventricular fractional shortening, left ventricular end-diastolic volume, left ventricular end- systolic volume, stroke volume, cardiac output. At the same time collecting the blood sample to measure cTnI, NT-pro BNP. The definition of LVSD was LVEF <50%. According to the prognosis of 28 days, children with severe sepsis were divided into survived group and nonsurvived group.Total of 50 pediatric patients who were diagnosed with severe sepsis (including septic shock) were enrolled, the incidence of LVSD was 52%. The 28-day mortality rate of severe sepsis was 34%. Multivariate logistic regression analyses for predictors of death in pediatric severe sepsis revealed that the 28-day mortality of severe sepsis was associated with mechanical ventilation (MV) within the first 6 hours of admission (odds ratio [OR], 0.01; 95% confidence interval [CI], 0.00-0.07) and total MV time (OR, 0.81; 95% CI, 0.68-0.97). The receiver operating characteristic curves LVEF (area under curve = 0.526), cTnI (area under curve = 0.480), and NT-pro BNP (area under curve = 0.624) were used to predict the 28-day mortality in pediatric severe sepsis. Follow-up echocardiography parameters for survived group and nonsurvived group showed no significant changes in LVEF, LVFS, stroke volume index, cardiac index (CI), left ventricular end-diastolic volume index and left ventricular end-systolic volume index at day 1, 2, 3, 7, and 10, except for CI at day 1 and 2. Kaplan-Meier plot of 28-day mortality and LVSD in pediatric severe sepsis showed there were no statistical differences (χ = 0.042, P = .837).LVSD occurs frequently in pediatric with severe sepsis. The 28-day mortality rate of severe sepsis was also high. In this study, none of LVSD, cTnI, and NT-proBNP was associated with the prognosis of pediatric severe sepsis.

Cardiac gene expression and function in a mouse model of community-acquired methicillin-resistant Staphylococcus aureus sepsis: Role of inflammatory caspases 1 and 11

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an important cause of invasive infections, including sepsis associated with myocardial dysfunction. Caspases 1 and 11, involved in activation of the inflammasome, have been shown to be critical in response to sepsis as well as myocardial dysfunction of numerous etiologies. We examined the survival, myocardial function, and production of inflammatory mediators in mice lacking caspases 1 and 11. Cas 1/11 KO mice demonstrated no significant difference in mortality or in cardiac shortening fraction relative to control mice. Cas 1/11 KO mice had significantly reduced upregulation of expression of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the heart relative to control mice after CA-MRSA infection, as well as reduced serum production of IL-1β, TNF-α, and IL-6, with no difference in IL-10 production. Other inflammatory mediators beyond IL-1β, TNF-α, and IL-6 may be involved in myocardial dysfunction in CA-MRSA sepsis.

Interventions for Pediatric Sepsis and Their Impact on Outcomes: A Brief Review

In the current era, pediatric sepsis remains a public health problem of significant prevalence and impact. With mortality rates practically unchanged over the years, this review hopes to briefly summarize the epidemiology and the current interventions for pediatric sepsis and point towards possible areas of improvement. Most pediatric studies of sepsis are either small, retrospective or observational. Given information technology spreading across country, and a stronger presence of clinical networks, development of multicenter prospective studies over the next decade should enable better treatments for pediatric sepsis, and improved outcomes.

Urine catecholamines in children with severe Enterovirus A71 infection: comparison with paediatric septic shock

Purpose: Hypercatecholaminemia-related heart failure has been proposed as the main cause of enterovirus A71-related (EV-A71) early mortality. The purpose of this study was to measure urine catecholamine concentrations in severe EV-A71-infected children. Methods: A total of 35 children, aged 2.5 ± 2.1 years, were divided into three groups. Group I: 15 septic shock patients, group II: 17 EV-A71-stage-2 patients, and group III: 3 EV-A71-stage-4 patients. The laboratory results, cardiac biomarkers and urine catecholamine concentrations were statistically analysed. Results: Group I had the highest C-reactive protein (CRP) levels and group II had the lowest B-type natriuretic peptide (BNP) and its N-terminal prohormone among the groups (p = 0.039, <0.01 and <0.01, respectively). Group III patients had significantly higher urine catecholamine and troponin-I values among the groups. If urine epinephrine (Epi) >134 ug/gCr, norepinephrine (NE) >176 ug/gCr and vanillylmandelic acid (VMA) >11.7 mg/gCr were used as the cutoff points to differentiate groups II and III, the sensitivities and specificity were all 100%. Conclusions: The significantly elevated urine catecholamine concentrations in EV-A71-stage-4 patients support the hypothesis that hypercatecholaminemia-related heart failure is involved in severe EV-A71 infection. Urine catecholamines could be used as reliable biomarkers for differentiation of severe EV-A71 infection with or without heart failure and septic shock.

Mitral Annular Plane Systolic Excursion as a Predictor of Mortality in Children With Septic Shock

OBJECTIVES

Myocardial dysfunction is well recognized in severe sepsis and septic shock. Echocardiography provides rapid, noninvasive, and bedside evaluation of cardiac function in patients with hemodynamic instability. Mitral annular plane systolic excursion is an M-mode-derived echocardiographic variable used to assess longitudinal left ventricular systolic function. No data are available about the uses of mitral annular plane systolic excursion in children with septic shock. Therefore, we aimed to assess the prognostic significance of mitral annular plane systolic excursion in children with septic shock and to correlate it with the most commonly used measures of left ventricular systolic function and myocardial injury.

DESIGN

A prospective cohort study.

SETTING

The study carried out at the PICU of Menoufia University Hospital in the period from March 2015 to September 2016.

PATIENTS

We serially enrolled 50 children with septic shock.

INTERVENTIONS

Complete diagnostic workup was performed for each patient including calculation of Pediatric Risk of Mortality III score. Transthoracic echocardiography was done to obtain mitral annular plane systolic excursion and the left ventricular ejection fraction measurement within 24 hours of inclusion then repeated on third and fifth days. Patients were followed up until hospital discharge or death. The predictive power of mitral annular plane systolic excursion was determined using the receiver operating characteristic curve.

MEASUREMENTS AND MAIN RESULTS

Mitral annular plane systolic excursion was significantly lower in nonsurvivors compared with survivors (p < 0.001). Receiver operating characteristic curve analysis showed an area under the curve of 0.892 for mitral annular plane systolic excursion on day 1. The cut-off point was 7.9 mm with 82.76% sensitivity and 80.95% specificity. Furthermore, follow-up of the patient's systolic function showed that mitral annular plane systolic excursion was significantly lower in nonsurvivors compared with survivors on days of follow-up, whereas left ventricular ejection fraction was not significantly different between survivors and nonsurvivors at any day. Mitral annular plane systolic excursion was positively correlated with left ventricular ejection fraction (p = 0.044) and duration of hospital stay (p < 0.001) and negatively correlated with Pediatric Risk of Mortality III score (p < 0.001) and cardiac troponin I level (p < 0.001).

CONCLUSIONS

Measurement of mitral annular plane systolic excursion at admission added a prognostic value in septic shock children. Compared with the left ventricular ejection fraction, longitudinal systolic function might be more sensitive in the detection of myocardial dysfunction in critically ill children and should receive more attention.

Confidence level of pediatric trainees in management of shock states

AIM

To assess overall confidence level of trainees in assessing and treating shock, we sought to improve awareness of recurrent biases in clinical decision-making to help address appropriate educational interventions.

METHODS

Pediatric trainees on a national listserv were offered the opportunity to complete an electronic survey anonymously. Four commonly occurring clinical scenarios were presented, and respondents were asked to choose whether or not they would give fluid, rank factors utilized in decision-making, and comment on confidence level in their decision.

RESULTS

Pediatric trainees have a very low confidence level for assessment and treatment of shock. Highest confidence level is for initial assessment and treatment of shock involving American College of Critical Care Medicine/Pediatric Advanced Life Support recommendations. Children with preexisting cardiac comorbidities are at high risk of under-resuscitation.

CONCLUSION

Pediatric trainees nationwide have low confidence in managing various shock states, and would benefit from guidance and teaching around certain common clinical situations.

The Trend of β3-Adrenergic Receptor in the Development of Septic Myocardial Depression: A Lipopolysaccharide-Induced Rat Septic Shock Model

Septic shock with low cardiac output is very common in children. However, the mechanism underlying myocardial depression is unclear. The role of β3-AR in the development of myocardial depression in sepsis is unknown. In the present study, we generated an adolescent rat model of hypodynamic septic shock induced by lipopolysaccharide (LPS). Neonatal cardiomyocytes were also treated with LPS to mimic myocardial depression in sepsis, which was confirmed via an in vivo left ventricular hemodynamic study, and measurements of contractility and the Ca2+ transient in isolated adolescent and neonatal cardiomyocytes. After 16 h of LPS treatment, cultured neonatal cardiomyocytes showed a diminished Ca2+ transient amplitude associated with an increase in the β3-AR level. With the addition of a β3-AR agonist, the Ca2+ transient in LPS-treated neonatal rat cardiomyocytes gradually decreased over time; such a change was absent in cells treated with nitric oxide synthase (NOS) inhibitors prior to treatment with a β3-AR agonist. In adolescent rats with septic myocardial depression, cardiac function declined as indicated by decreased MAP, dP/dtmax, and dP/dtmix for 6 h after LPS injection; however, the β3-AR level first increased 2 h after LPS treatment and then decreased 6 h after LPS treatment in the absence of exogenous catecholamines. The results indicate that, in vitro, at the cellular level β3-AR may be involved in the development of myocardial depression (Ca2+ transient depression) in sepsis through NOS signaling pathways; however, in vivo, a complicated mechanism for modulating β3-AR may exist.

Assessment of Myocardial Function and Injury by Echocardiography and Cardiac Biomarkers in African Children With Severe Plasmodium falciparum Malaria

OBJECTIVES

Perturbed hemodynamic function complicates severe malaria. The Fluid Expansion as Supportive Therapy trial demonstrated that fluid resuscitation, involving children with severe malaria, was associated with increased mortality, primarily due to cardiovascular collapse, suggesting that myocardial dysfunction may have a role. The aim of this study was to characterize cardiac function in children with severe malaria.

DESIGN

A prospective observational study with clinical, laboratory, and echocardiographic data collected at presentation (T0) and 24 hours (T1) in children with severe malaria. Cardiac index and ejection fraction were calculated at T0 and T1. Cardiac troponin I and brain natriuretic peptide were measured at T0. We compared clinical and echocardiographic variables in children with and without severe malarial anemia (hemoglobin < 5 mg/dL) at T0 and T1.

SETTING

Mbale Regional Referral Hospital.

PATIENTS

Children 3 months to 12 years old with severe falciparum malaria.

INTERVENTIONS

Usual care.

MEASUREMENTS AND MAIN RESULTS

We enrolled 104 children, median age 23.3 months, including 61 children with severe malarial anemia. Cardiac troponin I levels were elevated (> 0.1 ng/mL) in n equals to 50, (48%), and median brain natriuretic peptide was within normal range (69.1 pg/mL; interquartile range, 48.4-90.8). At T0, median Cardiac index was significantly higher in the severe malarial anemia versus nonsevere malarial anemia group (6.89 vs 5.28 L/min/m) (p = 0.001), which normalized in both groups at T1 (5.60 vs 5.13 L/min/m) (p = 0.452). Cardiac index negatively correlated with hemoglobin, r equals to -0.380 (p < 0.001). Four patients (3.8%) had evidence of depressed cardiac systolic function (ejection fraction < 45%). Overall, six children died, none developed pulmonary edema, biventricular failure, or required diuretic treatment.

CONCLUSIONS

Elevation of cardiac index, due to increased stroke volume, in severe malaria is a physiologic response to circulatory compromise and correlates with anemia. Following whole blood transfusion and antimalarial therapy, cardiac index in severe malarial anemia returns to normal. The majority (> 96%) of children with severe malaria have preserved myocardial systolic function. Although there is evidence for myocardial injury (elevated cardiac troponin I), this does not correlate with cardiac dysfunction.

Role of echocardiography in reducing shock reversal time in pediatric septic shock: a randomized controlled trial

OBJECTIVE

To evaluate the role of echocardiography in reducing shock reversal time in pediatric septic shock.

METHODS

A prospective study conducted in the pediatric intensive care unit of a tertiary care teaching hospital from September 2013 to May 2016. Ninety septic shock patients were randomized in a 1:1 ratio for comparing the serial echocardiography-guided therapy in the study group with the standard therapy in the control group regarding clinical course, timely treatment, and outcomes.

RESULTS

Shock reversal was significantly higher in the study group (89% vs. 67%), with significantly reduced shock reversal time (3.3 vs. 4.5 days). Pediatric intensive care unit stay in the study group was significantly shorter (8±3 vs. 14±10 days). Mortality due to unresolved shock was significantly lower in the study group. Fluid overload was significantly lower in the study group (11% vs. 44%). In the study group, inotropes were used more frequently (89% vs. 67%) and initiated earlier (12[0.5-24] vs. 24[6-72]h) with lower maximum vasopressor inotrope score (120[30-325] vs. 170[80-395]), revealing predominant use of milrinone (62% vs. 22%).

CONCLUSION

Serial echocardiography provided crucial data for early recognition of septic myocardial dysfunction and hypovolemia that was not apparent on clinical assessment, allowing a timely management and resulting in shock reversal time reduction among children with septic shock.

Toll-like receptor 4-induced ryanodine receptor 2 oxidation and sarcoplasmic reticulum Ca2+ leakage promote cardiac contractile dysfunction in sepsis

Studies suggest the potential role of a sarcoplasmic reticulum (SR) Ca²⁺ leak in cardiac contractile dysfunction in sepsis. However, direct supporting evidence is lacking, and the mechanisms underlying this SR leak are poorly understood. Here, we investigated the changes in cardiac Ca²⁺ handling and contraction in LPS-treated rat cardiomyocytes and a mouse model of polymicrobial sepsis produced by cecal ligation and puncture (CLP). LPS decreased the systolic Ca²⁺ transient and myocyte contraction as well as SR Ca²⁺ content. Meanwhile, LPS increased Ca²⁺ spark-mediated SR Ca²⁺ leak. Preventing the SR leak with ryanodine receptor (RyR) blocker tetracaine restored SR load and increased myocyte contraction. Similar alterations in Ca²⁺ handling were observed in cardiomyocytes from CLP mice. Treatment with JTV-519, an anti-SR leak drug, restored Ca²⁺ handling and improved cardiac function. In the LPS-treated cardiomyocytes, mitochondrial reactive oxygen species and oxidative stress in RyR2 were increased, whereas the levels of the RyR2-associated FK506-binding protein 1B (FKBP12.6) were decreased. The Toll-like receptor 4 (TLR4)-specific inhibitor TAK-242 reduced the oxidative stress in LPS-treated cells, decreased the SR leak, and normalized Ca²⁺ handling and myocyte contraction. Consistently, TLR4 deletion significantly improved cardiac function and corrected abnormal Ca²⁺ handling in the CLP mice. This study provides evidence for the critical role of the SR Ca²⁺ leak in the development of septic cardiomyopathy and highlights the therapeutic potential of JTV-519 by preventing SR leak. Furthermore, it reveals that TLR4 activation-induced mitochondrial reactive oxygen species production and the resulting oxidative stress in RyR2 contribute to the SR Ca²⁺ leak.

Update on pediatric sepsis: a review

BACKGROUND

Sepsis is one of the leading causes of mortality among children worldwide. Unfortunately, however, reliable evidence was insufficient in pediatric sepsis and many aspects in clinical practice actually depend on expert consensus and some evidence in adult sepsis. More recent findings have given us deep insights into pediatric sepsis since the publication of the Surviving Sepsis Campaign guidelines 2012.

MAIN TEXT

New knowledge was added regarding the hemodynamic management and the timely use of antimicrobials. Quality improvement initiatives of pediatric "sepsis bundles" were reported to be successful in clinical outcomes by several centers. Moreover, a recently published global epidemiologic study (the SPROUT study) did not only reveal the demographics, therapeutic interventions, and prognostic outcomes but also elucidated the inappropriateness of the current definition of pediatric sepsis.

CONCLUSIONS

With these updated knowledge, the management of pediatric sepsis would be expected to make further progress. In addition, it is meaningful that the fundamental data on which future research should be based were established through the SPROUT study.

Rolipram Improves Outcome in a Rat Model of Infant Sepsis-Induced Cardiorenal Syndrome

While the mortality rate associated with sepsis in children has fallen over the years, it still remains unacceptably high. The development of both acute cardiac dysfunction and acute kidney injury during severe sepsis is categorized as type 5 cardiorenal syndrome (CRS) and is poorly understood in infants. To address this lack of understanding and the need for an appropriate animal model in which to conduct relevant preclinical studies, we developed a model of infant sepsis-induced CRS in rat pups then evaluated the therapeutic potential of the phosphodiesterase (PDE) 4 inhibitor, rolipram. Rat pups at 17-18-days old were subjected to cecal ligation and puncture (CLP) to induce fecal polymicrobial sepsis. Uptake of Evans Blue dye was used to assess renal microvascular leakage. Intravital videomicroscopy was used to assess renal microvascular perfusion and oxidant generation. Glomerular filtration rate (GFR) was used to assess renal function. Left ventricular (LV) catheterization and echocardiography were used to assess cardiac function. Impairment of both cardiac and renal function developed rapidly following CLP, indicating type 5 CRS. Most notable were the rapid decline in LV diastolic function, the decline in cardiac output, renal microvascular failure, and the decline in GFR. A dose-response study with rolipram determined 0.1 mg/kg, ip as the lowest most efficacious dose to protect the renal microcirculation. Rolipram was then evaluated using a clinically relevant delayed dosing paradigm (a single dose at 6 h post-CLP). With delayed dosing, rolipram restored the renal microcirculation and reduced microvascular leakage but did not reduce oxidant generation in the kidney nor restore GFR. In contrast, delayed dosing with rolipram restored cardiac function. Rolipram also improved 4-days survival. In summary, CLP in the rat pup produces a clinically relevant pediatric model of sepsis-induced CRS. The PDE4 inhibitor rolipram was effective in improving renal microvascular function and cardiac function, which improved mortality. These findings suggest that rolipram should be evaluated further as adjunctive therapy for the septic infant with CRS.

Cardiac dysfunction and ferritin as early markers of severity in pediatric sepsis

OBJECTIVE

The aim of this study was to verify the association of echocardiogram, ferritin, C-reactive protein, and leukocyte count with unfavorable outcomes in pediatric sepsis.

METHODS

A prospective cohort study was carried out from March to December 2014, with pediatric critical care patients aged between 28 days and 18 years. Inclusion criteria were diagnosis of sepsis, need for mechanical ventilation for more than 48h, and vasoactive drugs. Serum levels of C-reactive protein, ferritin, and leukocyte count were collected on the first day (D0), 24h (D1), and 72h (D3) after recruitment. Patients underwent transthoracic echocardiography to determine the ejection fraction of the left ventricle on D1 and D3. The outcomes measured were length of hospital stay and in the pediatric intensive care unit, mechanical ventilation duration, free hours of VM, duration of use of inotropic agents, maximum inotropic score, and mortality.

RESULTS

Twenty patients completed the study. Patients with elevated ferritin levels on D0 had also fewer ventilator-free hours (p=0.046) and higher maximum inotropic score (p=0.009). Patients with cardiac dysfunction by echocardiogram on D1 had longer hospital stay (p=0.047), pediatric intensive care unit stay (p=0.020), duration of mechanical ventilation (p=0.011), maximum inotropic score (p=0.001), and fewer ventilator-free hours (p=0.020).

CONCLUSION

Cardiac dysfunction by echocardiography and serum ferritin value was significantly associated with unfavorable outcomes in pediatric patients with sepsis.

Characterization of Myocardial Dysfunction in Fluid- and Catecholamine-Refractory Pediatric Septic Shock and Its Clinical Significance

PURPOSE:

Myocardial dysfunction is a known complication in patients with pediatric septic shock (PSS); however, its clinical significance remains unclear. The purpose of this study was to characterize left ventricular (LV) and right ventricular (RV) dysfunction and their prevalence in patients with PSS using echocardiography (echo) and to investigate their associations with the severity of illness and clinical outcomes.

METHODS:

Retrospective chart review between 2010 and 2015 from 2 tertiary care pediatric intensive care units. Study included 78 patients (mean age 9.3 ± 7 years) from birth up to 21 years who fulfilled criteria for fluid- and catecholamine-refractory septic shock. Echocardiographic parameters of systolic, diastolic, and global function were measured offline. They were correlated with admission Pediatric Risk of Mortality III (PRISM III) and Pediatric Logistic Organ Dysfunction scores, vasoactive-inotrope score (VIS), β-type natriuretic peptide (BNP), lactate, type of shock, duration of mechanical ventilation (MV), intensive care unit and hospital length of stay, and mortality.

RESULTS:

Overall, 28-day mortality was 26%, and 88% patients required MV. Prevalence of LV dysfunction was 72% and RV dysfunction was 63%. LV systolic dysfunction (fractional shortening z score <-2) was significantly associated with PRISM III, VIS, and BNP. RV systolic dysfunction (tricuspid annular plane systolic excursion z score <-2) was significantly associated with cold shock. LV and RV diastolic dysfunction did not have any significant clinical associations. No echocardiographic measures were associated with mortality.

CONCLUSION:

Myocardial dysfunction is highly prevalent in PSS but is not associated with mortality. LV systolic dysfunction is associated with a higher severity of illness, use of vasoactives, and BNP, whereas RV systolic dysfunction is associated with cold shock. Further studies are needed to determine the utility of echo in the bedside management of patients with PSS.