Risk factors for death in children and adolescents with cancer and sepsis/septic shock

A Need for a Novel Survival Risk Scoring System for Intensive Care Admissions Due to Sepsis in Pediatric Hematology/Oncology Patients

Background: Children with hemato-oncological diseases or following stem cell transplantation (SCT) are at high risk for life-threatening infections; sepsis in this population constitutes a substantial proportion of pediatric intensive care unit (PICU) admissions. The current pediatric prognostic scoring tools to evaluate illness severity and mortality risk are designed for the general pediatric population and may not be adequate for this vulnerable subpopulation. Methods: Retrospective analysis was performed on all PICU admissions for sepsis in children with hemato-oncological diseases or post-SCT, in a single tertiary pediatric hospital between 2008 and 2021 (n = 233). We collected and analyzed demographic, clinical, and laboratory data and outcomes for all patients, and evaluated the accuracy of two major prognostic scoring tools, the Pediatric Logistic Organ Dysfunction-2 (PELOD-2) and the Pediatric Risk of Mortality III (PRISM III). Furthermore, we created a new risk-assessment model that contains additional parameters uniquely relevant to this population. Results: The survival rate for the cohort was 83%. The predictive accuracies of PELOD-2 and PRISM III, as determined by the area under the curve (AUC), were 83% and 78%, respectively. Nine new parameters were identified as clinically significant: age, SCT, viral infection, fungal infection, central venous line removal, vasoactive inotropic score, bilirubin level, C-reactive protein level, and prolonged neutropenia. Unique scoring systems were established by the integration of these new parameters into the algorithm; the new systems significantly improved their predictive accuracy to 91% (p = 0.01) and 89% (p < 0.001), respectively. Conclusions: The predictive accuracies (AUC) of the PELOD-2 and PRISM III scores are limited in children with hemato-oncological diseases admitted to PICU with sepsis. These results highlight the need to develop a risk-assessment tool adjusted to this special population. Such new scoring should represent their unique characteristics including their degree of immunosuppression and be validated in a large multi-center prospective study.

Hematologic Dysfunction Criteria in Critically Ill Children: The PODIUM Consensus Conference

CONTEXT

Studies of organ dysfunction in children are limited by a lack of consensus around organ dysfunction criteria.

OBJECTIVES

To derive evidence-informed, consensus-based criteria for hematologic dysfunction in critically ill children.

DATA SOURCES

Data sources included PubMed and Embase from January 1992 to January 2020.

STUDY SELECTION

Studies were included if they evaluated assessment/scoring tools to screen for hematologic dysfunction and assessed outcomes of mortality, functional status, organ-specific outcomes, or other patient-centered outcomes. Studies of adults or premature infants, animal studies, reviews/commentaries, small case series, and non-English language studies with inability to determine eligibility were excluded.

DATA EXTRACTION

Data were abstracted from each eligible study into a standard data extraction form along with risk of bias assessment.

RESULTS

Twenty-nine studies were included. The systematic review supports the following criteria for hematologic dysfunction: thrombocytopenia (platelet count <100000 cells/µL in patients without hematologic or oncologic diagnosis, platelet count <30000 cells/µL in patients with hematologic or oncologic diagnoses, or platelet count decreased ≥50% from baseline; or leukocyte count <3000 cells/µL; or hemoglobin concentration between 5 and 7 g/dL (nonsevere) or <5 g/dL (severe).

LIMITATIONS

Most studies evaluated pre-specified thresholds of cytopenias. No studies addressed associations between the etiology or progression of cytopenias overtime with outcomes, and no studies evaluated cellular function.

CONCLUSIONS

Hematologic dysfunction, as defined by cytopenia, is a risk factor for poor outcome in critically ill children, although specific threshold values associated with increased mortality are poorly defined by the current literature.

Criteria for Pediatric Sepsis-A Systematic Review and Meta-Analysis by the Pediatric Sepsis Definition Taskforce

OBJECTIVE

To determine the associations of demographic, clinical, laboratory, organ dysfunction, and illness severity variable values with: 1) sepsis, severe sepsis, or septic shock in children with infection and 2) multiple organ dysfunction or death in children with sepsis, severe sepsis, or septic shock.

DATA SOURCES

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched from January 1, 2004, and November 16, 2020.

STUDY SELECTION

Case-control studies, cohort studies, and randomized controlled trials in children greater than or equal to 37-week-old postconception to 18 years with suspected or confirmed infection, which included the terms "sepsis," "septicemia," or "septic shock" in the title or abstract.

DATA EXTRACTION

Study characteristics, patient demographics, clinical signs or interventions, laboratory values, organ dysfunction measures, and illness severity scores were extracted from eligible articles. Random-effects meta-analysis was performed.

DATA SYNTHESIS

One hundred and six studies met eligibility criteria of which 81 were included in the meta-analysis. Sixteen studies (9,629 patients) provided data for the sepsis, severe sepsis, or septic shock outcome and 71 studies (154,674 patients) for the mortality outcome. In children with infection, decreased level of consciousness and higher Pediatric Risk of Mortality scores were associated with sepsis/severe sepsis. In children with sepsis/severe sepsis/septic shock, chronic conditions, oncologic diagnosis, use of vasoactive/inotropic agents, mechanical ventilation, serum lactate, platelet count, fibrinogen, procalcitonin, multi-organ dysfunction syndrome, Pediatric Logistic Organ Dysfunction score, Pediatric Index of Mortality-3, and Pediatric Risk of Mortality score each demonstrated significant and consistent associations with mortality. Pooled mortality rates varied among high-, upper middle-, and lower middle-income countries for patients with sepsis, severe sepsis, and septic shock (p < 0.0001).

CONCLUSIONS

Strong associations of several markers of organ dysfunction with the outcomes of interest among infected and septic children support their inclusion in the data validation phase of the Pediatric Sepsis Definition Taskforce.

Therapeutics for paediatric oncological emergencies

Background

With advancements in the field of oncology, cancer survival rates have improved dramatically but modern cancer treatments also come with an increasing number of disease and treatment-associated complications. This article provides an updated narrative review on the pathophysiology, clinical presentations and latest management strategies for common paediatric oncological emergencies.

Methods

An extensive PubMed^® search of all human studies in the English literature was performed in Clinical Queries for different oncology syndromes and conditions using the following Medical Subject Headings: “tumour lysis syndrome”, “hyperleukocytosis”, “disseminated intravascular coagulation”, “superior mediastinal syndrome”, “superior vena cava syndrome”, “sepsis”, “severe inflammatory response syndrome”, “acute respiratory distress syndrome”, “posterior reversible encephalopathy syndrome” and “reversible posterior leukoencephalopathy syndrome”. Categories were limited to clinical trials and reviews for ages from birth to 18 years.

Results

The general description, presentation and management of these oncologic emergencies are systematically described. Early recognition along with prompt and proactive treatment can reduce the chances of potential complications and improve the clinical outcomes, thereby improving not only survival rates in oncology patients but also their clinical outcomes and quality of life.

Conclusions

Oncologic emergencies are associated with significant mortality and morbidity. Healthcare professionals involved with the care of oncology patients must be vigilant of these emergencies.

Respiratory Variations in Aortic Blood Flow to Predict Volume Responsiveness in Ventilated Children With Leukemia and Neutropenic Septic Shock

OBJECTIVES

To investigate whether respiratory variations in aortic blood flow by echocardiography can accurately predict volume responsiveness in ventilated children with leukemia and neutropenic septic shock.

DESIGN

A prospective study.

SETTING

A 25-bed PICU of a tertiary hospital.

PATIENTS

Mechanically ventilated children with leukemia who had been exposed to anthracyclines and exhibited neutropenic septic shock were enrolled.

INTERVENTIONS

Transthoracic echocardiography was performed to monitor the aortic blood flow before and after fluid administration.

MEASUREMENTS AND MAIN RESULTS

After volume expansion, left ventricular stroke volume increased by greater than or equal to 15% in 16 patients (responders) and less than 15% in 14 patients (nonresponders). The performance of respiratory variation in velocity time integral of aortic blood flow and respiratory variation in peak velocity of aortic blood flow for predicting volume responsiveness, as determined by the area under the receiver operating characteristic curve, was 0.74 (95% CI, 0.55-0.94; p = 0.025) and 0.71 (95% CI, 0.53-0.90; p = 0.048), respectively. Positive end-expiratory pressure was higher in nonresponders than in responders (p = 0.035).

CONCLUSIONS

Respiratory variation in velocity time integral of aortic blood flow and respiratory variation in peak velocity of aortic blood flow derived from transthoracic echocardiography showed only a fair reliability in predicting volume responsiveness in ventilated children with leukemia and neutropenic septic shock.

PICU mortality of children with cancer admitted to pediatric intensive care unit a systematic review and meta-analysis

BACKGROUND

Outcomes for children diagnosed with cancer have improved dramatically over the past 20 years. However, although 40% of pediatric cancer patients require at least one intensive care admission throughout their disease course, PICU outcomes and resource utilization by this population have not been rigorously studied in this specific group.

METHODS

Using a systematic strategy, we searched Medline, Embase, and CINAHL databases for articles describing PICU mortality of pediatric cancer patients admitted to PICU. Two investigators independently applied eligibility criteria, assessed data quality, and extracted data. We pooled PICU mortality estimates using random-effects models and examined mortality trends over time using meta-regression models.

RESULTS

Out of 1218 identified manuscripts, 31 studies were included covering 16,853 PICU admissions with the majority being retrospective in nature. Overall pooled weighted mortality was 27.8% (95% confidence interval (CI), 23.7-31.9%). Mortality decreased slightly over time when post-operative patients were excluded. The use of mechanical ventilation (odds ratio (OR): 18.49 [95% CI 13.79-24.78], p < 0.001), inotropic support (OR: 14.05 [95% CI 9.16-21.57], p < 0.001), or continuous renal replacement therapy (OR: 3.24 [95% CI 1.31-8.04], p = 0.01) was significantly associated with PICU mortality.

CONCLUSIONS

PICU mortality rates of pediatric cancer patients are far higher when compared to current mortality rates of the general PICU population. PICU mortality has remained relatively unchanged over the past decades, a slight decrease was only seen when post-operative patients were excluded. This compared infavorably with the improved mortality seen in adults with cancer admitted to ICU, where research-led improvements have led to the paradigm of unlimited, aggressive ICU management without any limitations on resuscitations status, for a time-limited trial.

Variability of mitochondrial respiration in relation to sepsis-induced multiple organ dysfunction

Ample experimental evidence suggests that sepsis could interfere with any mitochondrial function; however, the true role of mitochondrial dysfunction in the pathogenesis of sepsis-induced multiple organ dysfunction is still a matter of controversy. This review is primarily focused on mitochondrial oxygen consumption in various animal models of sepsis in relation to human disease and potential sources of variability in experimental results documenting decrease, increase or no change in mitochondrial respiration in various organs and species. To date, at least three possible explanations of sepsis-associated dysfunction of the mitochondrial respiratory system and consequently impaired energy production have been suggested: 1. Mitochondrial dysfunction is secondary to tissue hypoxia. 2. Mitochondria are challenged by various toxins or mediators of inflammation that impair oxygen utilization (cytopathic hypoxia). 3. Compromised mitochondrial respiration could be an active measure of survival strategy resembling stunning or hibernation. To reveal the true role of mitochondria in sepsis, sources of variability of experimental results based on animal species, models of sepsis, organs studied, or analytical approaches should be identified and minimized by the use of appropriate experimental models resembling human sepsis, wider use of larger animal species in preclinical studies, more detailed mapping of interspecies differences and organ-specific features of oxygen utilization in addition to use of complex and standardized protocols evaluating mitochondrial respiration.

Variation in the levels of IL-6 in pediatric patients with severe bacterial infectious diseases and correlation analysis between the levels of IL-6 and procalcitonin

The objective of the present study was to investigate variations in the levels of interleukin (IL)-6, procalcitonin (PCT), and C-reactive protein (CRP) in children with severe bacterial infectious diseases and to analyze the correlation between the levels of IL-6 and PCT to determine the value of combined diagnosis with IL-6 and PCT. We analyzed 126 patients admitted to Xuzhou Children's Hospital for treatment, who were divided into severe bacterial infection (observation group, n=65) and non-bacterial infection groups (control group, n=61). The levels of IL-6, PCT, and CRP were measured and compared between the two groups. Data from both groups were statistically analyzed. The levels of IL-6, PCT, and CRT in the observation group were significantly higher than those in the control group (P<0.01); in the observation group, the levels of IL-6 and PCT on the 5th and 10th day after treatment were significantly lower than those before treatment (P<0.01); PCT showed better value for diagnosing severe bacterial infections compared with IL-6 and CRP; there was a positive correlation between the levels of IL-6 and PCT in the observation group; and the sensitivity and specificity of combined diagnosis with IL-6 and PCT for severe bacterial infection was 93.84% and 96.72%, respectively, which were significantly higher than those for diagnosis with only IL-6 (P<0.01). In conclusion, IL-6 combined with PCT can serve as an indicator with high sensitivity for detection of severe bacterial infections in children, which is of great significance for the differential diagnosis of severe bacterial infections in the early stage.

Risk factors for sepsis-related death in children and adolescents with hematologic and malignant diseases

BACKGROUND

The aim of this study was to elucidate risk factors for mortality after developing sepsis in pediatric patients with hematologic and malignant disorders.

METHODS

A total of 90 patients (43 boys, 47 girls) with various hematologic and malignant diseases who experienced sepsis between June 2006 and March 2014 were enrolled. Clinical and laboratory features of 134 episodes of sepsis observed in the 90 patients were compared between those with and without sepsis-related death which was defined as death within 14 days after sepsis.

RESULTS

Age at hospitalization, sex, and type of underlying disease did not differ between patients with and without sepsis-related death. Sepsis episode-based univariate analysis identified patients with a history of relapse or in a refractory state of underlying disease (p<0.01), those with high C-reactive protein concentrations (≥50 mg/L) at the beginning of fever (p<0.01), those who had undergone hematopoietic stem cell transplantation (p<0.01), and those who were forced to change initial antibiotics (p = 0.02) because of being at high risk of sepsis-related death. The former two factors were further confirmed by multivariate analysis. More than half (52.9%) the isolates from sepsis-related death were Gram-positive cocci resistant to β-lactam antibiotics, but susceptible to vancomycin.

CONCLUSION

It was found that a history of relapse, a refractory state of underlying disease, and high C-reactive protein concentrations at the beginning of fever were significant risk factors for mortality after developing sepsis. Survival rate of patients with risk factors raised in this study might be improved by early introduction of vancomycin.

Early changes in SOFA score as a prognostic factor in pediatric oncology patients requiring mechanical ventilatory support

PURPOSE

To evaluate whether changes in outcome prediction scores during the first 72 hours after admission to a pediatric intensive care unit (PICU) are more predictive of outcome than single assessments at admission in pediatric oncology patients requiring mechanical ventilatory support for more than 3 days.

PATIENTS AND METHODS

The medical records of 54 consecutive pediatric oncology patients requiring mechanical ventilation over 72 hours in the PICU of the Asan Medical Center, Seoul, Korea, between January 2006 and December 2008, were retrospectively reviewed.

RESULTS

Although both initial Sequential Organ Failure Assessment (SOFA) score and change in SOFA score (Δ-SOFA) correlated well with mortality, Δ-SOFA score showed a significantly stronger correlation (P<0.001) and a larger area under the receiver operating characteristic curve than did initial SOFA score. Patients with positive and negative Δ-SOFA scores showed statistically significant differences in mortality (18.5% vs. 88.2%, P<0.001). In addition, early changes in respiratory parameters, such as PaO₂/FiO₂ (P/F) ratio, oxygenation index (OI), and ventilation index (VI), evaluated serially during the first 3 days, also correlated with mortality. Patients showing improvement in these respiratory parameters displayed significantly lower mortality than did patients with worsening of these parameters (P<0.01).

CONCLUSIONS

Serial evaluation of SOFA score during the first few days after PICU admission was a good predictor of prognosis in pediatric oncology patients mechanically ventilated over 3 days. Independent of initial SOFA score, Δ-SOFA score during the first 72 hours closely correlated with outcome. Early changes in respiratory parameters, such as P/F ratio, OI, and VI, may also provide valuable prognostic information in such patients.