Pediatric Investigators Collaborative Network on Infections in Canada (PICNIC) study of admission and management variation in patients hospitalized with respiratory syncytial viral lower respiratory tract infection

Factors associated with severe respiratory syncytial virus infection among hospitalized children in Thammasat University Hospital

Background

Respiratory syncytial virus (RSV) is one of the most significant respiratory pathogens that causes acute lower respiratory tract infections (LRTI) early in life. Most children have a history of RSV infection within 24 months of age, and recurrent infections are common throughout life.

Methods

Children under five years of age were identified through a review of medical records with a diagnosis of RSV-LRTI between 2016 and 2020. Severe RSV-LRTI was defined as a prolonged length of stay (> 7 days), admission to the intensive care unit, need for mechanical ventilation, non-invasive positive pressure ventilation, or in-hospital mortality. Factors associated with severe RSV-LRTI were investigated using univariate and multivariate analyses.

Results

During the study period, 620 patients were diagnosed with RSV-LRTI and 249 (40.16%) patients had severe RSV-LRTI. In the multivariable logistic regression analysis, the factors for severe RSV-LRTI were being under 3 months (aOR 2.18 CI 1.39-3.43, p0.001), cardiovascular disease (aOR 3.55 CI 1.56-8.06, p0.002), gastrointestinal disease (aOR 5.91 CI 1.90-18.46, p0.002), genetic disease (aOR 7.33 CI 1.43-37.54, p0.017), and pulmonary disease (aOR 9.50, CI 4.56-19.80, p<0.001). Additionally, the presence of ≥ 2 co-morbidities (aOR 6.23 CI 2.81-14.81, p<0.016), experiencing illness for more than 5 days (aOR 3.33 CI 2.19-5.06, p<0.001), co-detection of influenza (aOR 8.62 CI 1.49-38.21, p0.015), and nosocomial RSV infection (aOR 9.13 CI 1.98-41.30, p0.012), markedly increased the risk of severe RSV-LTRI. The severe RSV-LRTI group demonstrated higher hospitalization expenses (median, US $720.77 vs $278.00, respectively; p<0.001), and three infants died in-hospital.

Conclusion

Children at high risk for RSV-LRTI due to underlying genetic and gastrointestinal diseases are at an increased risk for severe RSV-LRTI. Further studies to determine the cost-effectiveness of RSV immunization in these potential co-morbidities should be initiated to prioritize RSV immunization, especially in resource-constrained regions with limited availability of nirsevimab.

Respiratory Syncytial Virus Infections in Neonates: A Persisting Problem

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections in young infants. It is an enveloped, single-stranded, nonsegmented, negative-strand RNA virus, a member of the family Pneumoviridae. Globally, RSV is responsible for 2.3% of deaths among neonates 0-27 days of age. Respiratory syncytial virus infection is most common in children aged below 24 months. Neonates present with cough and fever. Respiratory syncytial virus-associated wheezing is seen in 20% infants during the first year of life of which 2-3% require hospitalization. Reverse transcriptase polymerase chain reaction (RT-PCR) gives fast results and has higher sensitivity compared with culture and rapid antigen tests and are not affected by passively administered antibody to RSV. Therapy for RSV infection of the LRT is mainly supportive, and preventive measures like good hygiene and isolation are the mainstay of management. Standard precautions, hand hygiene, breastfeeding and contact isolation should be followed for RSV-infected newborns. Recent AAP guidelines do not recommend pavilizumab prophylaxis for preterm infants born at 29-35 weeks without chronic lung disease, hemodynamically significant congenital heart disease and coexisting conditions. RSV can lead to long-term sequelae such as wheezing and asthma, associated with increased healthcare costs and reduced quality of life.

Association between surfactant protein B gene locus and acute bronchiolitis in infants

Purpose: The aim of this study was to investigate whether there is a relationship between surfactant protein B (SFTPB) C1580T polymorphism and acute bronchiolitis. Materials and Methods: The study analyzed the allele frequency and genotype distribution for the SFTPB C1580T polymorphism using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique in 103 acute bronchiolitis infants and 102 healthy infants. Results: The results showed no association between SFTPB C1580T polymorphism and clinical characteristics of acute bronchiolitis. The distribution of the CT genotype was higher in acute bronchiolitis infants (43%) than in healthy subjects (39%) and distribution of the TT genotype was found lower in acute bronchiolitis infants (38%) than in healthy subjects (41%). No significant differences in genotype distribution and allele frequency for the SFTPB C1580T polymorphism were found between case group and control group Conclusion: SFTPB C1580T gene polymorphism plays no important role in susceptibility to acute bronchiolitis. Further work on the relevance of SFTPB C1580T polymorphism in larger cohorts will require validating our results.

Neurally Adjusted Ventilator Assist in Infants With Acute Respiratory Failure: A Literature Scoping Review

OBJECTIVES

To map the evidence for neurally adjusted ventilatory assist strategies, outcome measures, and sedation practices in infants less than 12 months with acute respiratory failure using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidance.

DATA SOURCES

CINAHL, MEDLINE, COCHRANE, JBI, EMBASE, PsycINFO, Google scholar, BNI, AMED. Trial registers included the following: ClinicalTrials.gov, European Union clinical trials register, International Standardized Randomized Controlled Trial Number register. Also included were Ethos, Grey literature, Google, dissertation abstracts, EMBASE conference proceedings.

STUDY SELECTION

Abstracts were screened followed by review of full text. Articles incorporating a heterogeneous population of both infants and older children were assessed, and where possible, data for infants were extracted. Fifteen articles were included. Ten articles were primary research: randomized controlled trial (n = 3), cohort studies (n = 4), retrospective data analysis (n = 2), case series (n = 1). Other articles are expert opinion (n = 2), neurally adjusted ventilatory assist updates (n = 1), and a literature review (n = 2). Three studies included exclusively infants. We also included 12 studies reporting jointly on infants and children.

DATA EXTRACTION

A standardized data extraction tool was used.

DATA SYNTHESIS

Key findings were that evidence related to neurally adjusted ventilatory assist ventilation strategies in infants and related to specific primary conditions is limited. The setting of neurally adjusted ventilatory assist level is not consistent, and how to optimize this mode of ventilation was not documented. Outcome measures varied considerably, most studies focused on improvements in respiratory and physiological variables. Sedation use is variable with regard to medication type and dose. There is an indication that less sedation is required in patients receiving neurally adjusted ventilatory assist, but no conclusive evidence to support this.

CONCLUSIONS

This review highlights a lack of standardized strategies for neurally adjusted ventilatory assist ventilation and sedation practices among infants with acute respiratory failure. Studies were limited by small sample sizes and a lack of focus on specific patient groups. Robust studies are needed to provide evidence-based clinical recommendations for the use of neurally adjusted ventilatory assist in infants with acute respiratory failure.

Clinico demographic profiling of the Respiratory syncytial virus (RSV) infected children admitted in tertiary care hospital in North India

Background:

Acute bronchiolitis is fatal disease involving lower respiratory tract of infants and children of paediatric age group. Respiratory Syncytial Virus (RSV) is responsible for causing more than 70% hospital admissions of children aged less than 2 years thus making a necessity for accurate and timely diagnosis.

Aims:

The main aim of study was clinicodemographic correlation of RSV positive children presenting to our tertiary care hospital.

Setting and Design:

It is a retrospective study done between December to January 2018.

Materials and Methods:

Detection of RSV antigen from nasophyrangeal aspirates using Mouse Monoclonal anti RSV Antibody (by Novatetra) and Goat Anti Mouse Antibody conjugated with FITC as secondary antibody.

Results:

A total of 147 samples were received in the laboratory and 20 were tested as positive for RSV Antigen. Totally, 19/20 children were aged less than 1 year and with a male predominance. The most common symptom was cough and respiratory distress. Eight percent of the children showed wheezing and 18/20 required assisted ventilation. The clinical course in one child deteriorated leading to death of that patient.

Conclusions:

The timely diagnosis and management of RSV infected children is utmost needed to prevent morbidity and mortality. The premorbid conditions can assist to differentiate the viral from bacterial pneumonia and thus enable speedy recovery of the child.

Presumed Risk Factors and Biomarkers for Severe Respiratory Syncytial Virus Disease and Related Sequelae: Protocol for an Observational Multicenter, Case-Control Study From the Respiratory Syncytial Virus Consortium in Europe (RESCEU)

Respiratory syncytial virus (RSV) is the leading viral pathogen associated with acute lower respiratory tract infection and hospitalization in children < 5 years of age worldwide. While there are known clinical risk factors for severe RSV infection, the majority of those hospitalized are previously healthy infants. There is consequently an unmet need to identify biomarkers that predict host response, disease severity, and sequelae. The primary objective is to identify biomarkers of severe RSV acute respiratory tract infection (ARTI) in infants. Secondary objectives include establishing biomarkers associated with respiratory sequelae following RSV infection and characterizing the viral load, RSV whole-genome sequencing, host immune response, and transcriptomic, proteomic, metabolomic and epigenetic signatures associated with RSV disease severity. Six hundred thirty infants will be recruited across 3 European countries: the Netherlands, Spain, and the United Kingdom. Participants will be recruited into 2 groups: (1) infants with confirmed RSV ARTI (includes upper and lower respiratory tract infections), 500 without and 50 with comorbidities; and (2) 80 healthy controls. At baseline, participants will have nasopharyngeal, blood, buccal, stool, and urine samples collected, plus complete a questionnaire and 14-day symptom diary. At convalescence (7 weeks ± 1 week post-ARTI), specimen collection will be repeated. Laboratory measures will be correlated with symptom severity scores to identify corresponding biomarkers of disease severity.

CLINICAL TRIALS REGISTRATION

NCT03756766.

Multicenter Initial Guidance on Use of Antivirals for Children With Coronavirus Disease 2019/Severe Acute Respiratory Syndrome Coronavirus 2

BACKGROUND

Although coronavirus disease 2019 (COVID-19) is mild in nearly all children, a small proportion of pediatric patients develop severe or critical illness. Guidance is therefore needed regarding use of agents with potential activity against severe acute respiratory syndrome coronavirus 2 in pediatrics.

METHODS

A panel of pediatric infectious diseases physicians and pharmacists from 18 geographically diverse North American institutions was convened. Through a series of teleconferences and web-based surveys, a set of guidance statements was developed and refined based on review of best available evidence and expert opinion.

RESULTS

Given the typically mild course of pediatric COVID-19, supportive care alone is suggested for the overwhelming majority of cases. The panel suggests a decision-making framework for antiviral therapy that weighs risks and benefits based on disease severity as indicated by respiratory support needs, with consideration on a case-by-case basis of potential pediatric risk factors for disease progression. If an antiviral is used, the panel suggests remdesivir as the preferred agent. Hydroxychloroquine could be considered for patients who are not candidates for remdesivir or when remdesivir is not available. Antivirals should preferably be used as part of a clinical trial if available.

CONCLUSIONS

Antiviral therapy for COVID-19 is not necessary for the great majority of pediatric patients. For those rare cases of severe or critical disease, this guidance offers an approach for decision-making regarding antivirals, informed by available data. As evidence continues to evolve rapidly, the need for updates to the guidance is anticipated.

Multicenter Interim Guidance on Use of Antivirals for Children With Coronavirus Disease 2019/Severe Acute Respiratory Syndrome Coronavirus 2

BACKGROUND

Although coronavirus disease 2019 (COVID-19) is a mild infection in most children, a small proportion develop severe or critical illness. Data describing agents with potential antiviral activity continue to expand such that updated guidance is needed regarding use of these agents in children.

METHODS

A panel of pediatric infectious diseases physicians and pharmacists from 20 geographically diverse North American institutions was convened. Through a series of teleconferences and web-based surveys, a set of guidance statements was developed and refined based on review of the best available evidence and expert opinion.

RESULTS

Given the typically mild course of COVID-19 in children, supportive care alone is suggested for most cases. For children with severe illness, defined as a supplemental oxygen requirement without need for noninvasive or invasive mechanical ventilation or extracorporeal membrane oxygenation (ECMO), remdesivir is suggested, preferably as part of a clinical trial if available. Remdesivir should also be considered for critically ill children requiring invasive or noninvasive mechanical ventilation or ECMO. A duration of 5 days is appropriate for most patients. The panel recommends against the use of hydroxychloroquine or lopinavir-ritonavir (or other protease inhibitors) for COVID-19 in children.

CONCLUSIONS

Antiviral therapy for COVID-19 is not necessary for the great majority of pediatric patients. For children with severe or critical disease, this guidance offers an approach for decision-making regarding use of remdesivir.

Emergency room endotracheal intubation in children with bronchiolitis: A cohort study using a multicenter database

BACKGROUND AND AIMS

Bronchiolitis and asthma have a clinical overlap, and it has been shown that pediatric intensive care unit (PICU) patients with asthma undergoing endotracheal intubation in a community hospital emergency room (ER) have a shorter duration of mechanical ventilation (MV) and PICU length of stay (LOS) vs children undergoing intubation in a children's hospital. We aimed to determine if the setting of intubation (community vs children's hospital ER) is associated with the duration of MV and PICU LOS among children with bronchiolitis.

METHODS

With IRB approval, data in the Virtual Pediatric Systems (VPS, LLC) database were queried for bronchiolitis patients <24 months of age admitted to one of 103 predominantly North American PICUs between 1/2009 and 1/2016 who had an endotracheal tube in place at PICU admission. There were no exclusion criteria. Extracted data included ER type (community/external or children's hospital/internal), demographics, and reported comorbidities. Outcomes analyzed were duration of MV and PICU LOS. Multivariable linear regression was used to evaluate if intubation location was independently associated with the outcomes of interest.

RESULTS

Among 1934 patients, median age was 2.0 (IQR: 1.0-4.8) months, 51% were admitted from an external ER, 41% were White, 61% were male, and 28% had ≥1 comorbidity. Median duration of MV was 6.6 (4.6-9.5) days and the median PICU LOS was 7.0 (4.6-10.6) days. Children who underwent endotracheal intubation in a children's hospital ER had a modestly longer duration of MV (6.7 [4.4-9.4] vs 6.5 [5.2-9.6] days, P < .001, Mann-Whitney U) and longer PICU LOS (7.2 [4.8-10.8] vs 6.9 [4.2-10.1] days, P = .004, Mann-Whitney U). After adjusting for confounding variables, we did not observe a significant association between the location of endotracheal intubation and duration of MV or PICU LOS.

CONCLUSION

In this cohort, and unlike outcomes of near-fatal asthma, we observed that clinical outcomes of critical bronchiolitis were similar regardless of location of endotracheal intubation.

Assessing physical and respiratory distress in children with bronchiolitis admitted to a community hospital emergency department: A retrospective chart review

Introduction

Bronchiolitis is a leading cause of infant hospitalization with wide variation in its diagnosis and management, especially in smaller community hospitals. The objective of this study is to describe children admitted to a community-based hospital emergency department (ED) for bronchiolitis and explore alternate assessments of illness severity.

Methods

A retrospective chart review (January to September 2014) of 100 children, < 2 years old and meeting International Classification of Diseases 10 for bronchiolitis. Outcomes included demographics, symptoms, and interventions. In addition, the Respiratory Distress Assessment Instrument (RDAI) score was calculated using documented assessments of wheezing and retractions. Descriptive and comparative statistics were completed with p < 0.05 considered significant.

Results

The mean (standard deviation) age 10.6 (8.4) months, n = 41 females. Sixty-seven percent had a chest X-ray (CXR), 17% oral antibiotics, 65% bronchodilators, and 19% oral steroids; 19% were admitted in hospital. There was a significant difference in RDAI score between those given oral antibiotics (mean (95% CI), 6.35 (4.96–7.75)) versus not (4.70 (4.20–5.20)), p = 0.01. Those who received a CXR had a significantly higher oxygen flowrate (1.4 (0.6–2.1) litres per minute (lpm)) and worse physical appearance (tri-pod position, head bobbing) versus those who did not (0.15 (–0.05 to 0.35) lpm), p = 0.002 and p = 0.04, respectively.

Conclusions

A large number of children admitted to a community-based ED for bronchiolitis received unnecessary CXR and medications. Assessing physical and respiratory distress may be more effective at determining illness severity compared with radiological or laboratory testing. Local clinical practice guidelines may aid in optimal management of bronchiolitis for community-based EDs.

Assessing the quality of health care in the management of bronchiolitis in Australian children: a population-based sample survey

Background

Bronchiolitis is the most common cause of respiratory hospitalisation in children aged <2 years. Clinical practice guidelines (CPGs) suggest only supportive management of bronchiolitis. However, the availability of CPGs do not guarantee that they are used appropriately and marked variation in the clinical management exists. We conducted an assessment of guideline adherence in the management of bronchiolitis in children at a subnationally representative level including inpatient and ambulatory services in Australia.

Methods

We searched for national and international CPGs relating to management of bronchiolitis in children and identified 16 recommendations which were formatted into 40 medical record audit indicator questions. A retrospective medical record review assessing compliance with the CPGs was conducted across three types of healthcare setting: hospital inpatient admissions, emergency department (ED) presentations and general practice (GP) consultations in three Australian states for children aged <2 years receiving care in 2012 and 2013.

Results

Purpose-trained surveyors conducted 13 979 eligible indicator assessments across 796 visits for bronchiolitis at 119 sites. Guideline adherence for management of bronchiolitis was 77.3% (95% CI 72.6 to 81.5) for children attending EDs, 81.6% (95% CI 78.0 to 84.9) for inpatients and 52.3% (95% CI 44.8 to 59.7) for children attending GP consultations. While adherence to some individual indicators was high, overall adherence to documentation of 10 indicators relating to history taking and examination was poorest and estimated at 2.7% (95% CI 1.5 to 4.4).

Conclusions

The study is the first to assess guideline-adherence in both hospital (ED and inpatient) and GP settings. Our study demonstrated that while the quality of care for bronchiolitis was generally adherent to CPG indicators, specific aspects of management were deficient, especially documentation of history taking.

Predicting Appropriate Hospital Admission of Emergency Department Patients with Bronchiolitis: Secondary Analysis

Background

In children below the age of 2 years, bronchiolitis is the most common reason for hospitalization. Each year in the United States, bronchiolitis causes 287,000 emergency department visits, 32%-40% of which result in hospitalization. Due to a lack of evidence and objective criteria for managing bronchiolitis, clinicians often make emergency department disposition decisions on hospitalization or discharge to home subjectively, leading to large practice variation. Our recent study provided the first operational definition of appropriate hospital admission for emergency department patients with bronchiolitis and showed that 6.08% of emergency department disposition decisions for bronchiolitis were inappropriate. An accurate model for predicting appropriate hospital admission can guide emergency department disposition decisions for bronchiolitis and improve outcomes, but has not been developed thus far.

Objective

The objective of this study was to develop a reasonably accurate model for predicting appropriate hospital admission.

Methods

Using Intermountain Healthcare data from 2011-2014, we developed the first machine learning classification model to predict appropriate hospital admission for emergency department patients with bronchiolitis.

Results

Our model achieved an accuracy of 90.66% (3242/3576, 95% CI: 89.68-91.64), a sensitivity of 92.09% (1083/1176, 95% CI: 90.33-93.56), a specificity of 89.96% (2159/2400, 95% CI: 88.69-91.17), and an area under the receiver operating characteristic curve of 0.960 (95% CI: 0.954-0.966). We identified possible improvements to the model to guide future research on this topic.

Conclusions

Our model has good accuracy for predicting appropriate hospital admission for emergency department patients with bronchiolitis. With further improvement, our model could serve as a foundation for building decision-support tools to guide disposition decisions for children with bronchiolitis presenting to emergency departments.

International Registered Report Identifier (IRRID)

RR2-10.2196/resprot.5155

Bronchiolitis Admissions in a Lebanese Tertiary Medical Center: A 10 Years' Experience

Bronchiolitis and more specifically respiratory syncytial virus (RSV) bronchiolitis is a leading cause of global childhood morbidity and mortality. Despite the previous identification of possible risk factors associated with the severity of bronchiolitis, the data from Lebanon remains limited. We described the burden of bronchiolitis hospitalizations in children under 5 years of age in a tertiary care center in Lebanon from October 2004 to October 2014 and identified the risk factors associated with severe bronchiolitis. This was a retrospective cohort study conducted at the American University of Beirut Medical Center. Records of children younger than 5 years of age admitted with a diagnosis of bronchiolitis were reviewed. More than half the patients were RSV positive. RSV bronchiolitis was found to be significantly associated with longer hospital stay compared to children with non-RSV bronchiolitis (P = 0.007). Children exposed to smoking had an increased risk for longer hospital stay (P = 0.002) and were more likely to require ICU admission (P < 0.001) and supplemental oxygen (P = 0.045). Congenital heart disease was found to be a significant risk factor for severe bronchiolitis (P < 0.005). Conclusion: Patients with RSV bronchiolitis had a longer hospital stay compared to patients with non-RSV bronchiolitis. Exposure to smoking was associated with a more severe and complicated RSV infection. Congenital heart disease was the only risk factor significantly associated with all markers of bronchiolitis disease severity.

Appropriateness of Hospital Admission for Emergency Department Patients with Bronchiolitis: Secondary Analysis

Background

Bronchiolitis is the leading cause of hospitalization in children under 2 years of age. Each year in the United States, bronchiolitis results in 287,000 emergency department visits, 32%-40% of which end in hospitalization. Frequently, emergency department disposition decisions (to discharge or hospitalize) are made subjectively because of the lack of evidence and objective criteria for bronchiolitis management, leading to significant practice variation, wasted health care use, and suboptimal outcomes. At present, no operational definition of appropriate hospital admission for emergency department patients with bronchiolitis exists. Yet, such a definition is essential for assessing care quality and building a predictive model to guide and standardize disposition decisions. Our prior work provided a framework of such a definition using 2 concepts, one on safe versus unsafe discharge and another on necessary versus unnecessary hospitalization.

Objective

The goal of this study was to determine the 2 threshold values used in the 2 concepts, with 1 value per concept.

Methods

Using Intermountain Healthcare data from 2005-2014, we examined distributions of several relevant attributes of emergency department visits by children under 2 years of age for bronchiolitis. Via a data-driven approach, we determined the 2 threshold values.

Results

We completed the first operational definition of appropriate hospital admission for emergency department patients with bronchiolitis. Appropriate hospital admissions include actual admissions with exposure to major medical interventions for more than 6 hours, as well as actual emergency department discharges, followed by an emergency department return within 12 hours ending in admission for bronchiolitis. Based on the definition, 0.96% (221/23,125) of the emergency department discharges were deemed unsafe. Moreover, 14.36% (432/3008) of the hospital admissions from the emergency department were deemed unnecessary.

Conclusions

Our operational definition can define the prediction target for building a predictive model to guide and improve emergency department disposition decisions for bronchiolitis in the future.

Predictors and incidence of hospitalization due to respiratory syncytial virus (RSV)-associated lower respiratory tract infection (LRTI) in non-prophylaxed moderate-to-late preterm infants in Bosnia and Herzegovina

Prematurity is a risk factor for respiratory syncytial virus (RSV)-associated lower respiratory tract infections (LRTIs), due to immature humoral and cell-mediated immune system in preterm newborns, as well as their incomplete lung development. Palivizumab, a humanized monoclonal antibody against the F glycoprotein of RSV, is licensed for the prevention of severe RSV LRTI in children at high risk for the disease. This study is a part of a larger observational, retrospective-prospective epidemiological study (PONI) conducted at 72 sites across 23 countries in the northern temperate zone. The aim of our non-interventional study was to identify common predictors and factors associated with RSV LRTI hospitalization in non-prophylaxed, moderate-to-late preterm infants, born between 33 weeks and 0 days and 35 weeks and 6 days of gestation, and less than 6 months prior to or during the RSV season in Bosnia and Herzegovina (B&H). A total of 160 moderate-to-late preterm infants were included from four sites in B&H (Sarajevo, Tuzla, Mostar, and Banja Luka). We identified several significant intrinsic and extrinsic factors to be associated with the risk of RSV LRTI hospitalization in the preterm infants, including: comorbidities after birth, shorter hospital stay, admission to NICU/PICU while in the maternity ward, household smoking, low maternal age, breast feeding, number of family members, and history of family/paternal atopy. Overall, our results indicated that the risk of RSV LRTI in preterm newborns can be associated with different environmental and social/cultural factors, and further research is needed to comprehensively evaluate these associations.

Functional Impairment of Mononuclear Phagocyte System by the Human Respiratory Syncytial Virus

The mononuclear phagocyte system (MPS) comprises of monocytes, macrophages (MΦ), and dendritic cells (DCs). MPS is part of the first line of immune defense against a wide range of pathogens, including viruses, such as the human respiratory syncytial virus (hRSV). The hRSV is an enveloped virus that belongs to the Pneumoviridae family, Orthopneumovirus genus. This virus is the main etiological agent causing severe acute lower respiratory tract infection, especially in infants, children and the elderly. Human RSV can cause bronchiolitis and pneumonia and it has also been implicated in the development of recurrent wheezing and asthma. Monocytes, MΦ, and DCs significantly contribute to acute inflammation during hRSV-induced bronchiolitis and asthma exacerbation. Furthermore, these cells seem to be an important component for the association between hRSV and reactive airway disease. After hRSV infection, the first cells encountered by the virus are respiratory epithelial cells, alveolar macrophages (AMs), DCs, and monocytes in the airways. Because AMs constitute the predominant cell population at the alveolar space in healthy subjects, these cells work as major innate sentinels for the recognition of pathogens. Although adaptive immunity is crucial for viral clearance, AMs are required for the early immune response against hRSV, promoting viral clearance and controlling immunopathology. Furthermore, exposure to hRSV may affect the phagocytic and microbicidal capacity of monocytes and MΦs against other infectious agents. Finally, different studies have addressed the roles of different DC subsets during infection by hRSV. In this review article, we discuss the role of the lung MPS during hRSV infection and their involvement in the development of bronchiolitis.

Variability of Care in Infants with Severe Bronchiolitis: Less-Invasive Respiratory Management Leads to Similar Outcomes

OBJECTIVE

To compare the management of children with severe bronchiolitis requiring intensive care (based on duration of ventilatory support and duration of pediatric intensive care unit [PICU] stay) in 2 countries with differing pediatric transport and PICU organizations.

STUDY DESIGN

This was a prospective observational care study in 2 PICUs of tertiary care university hospitals, 1 in France and 1 in Canada. All children with bronchiolitis who required admission to the PICU between November 1, 2013, and March 31, 2014, were included.

RESULTS

A total of 194 children were included. Baseline characteristics and illness severity were similar at the 2 sites. There was a significant difference between centers in the use of invasive ventilation (3% in France vs 26% in Canada; P < .0001). The number of investigations performed from admission to emergency department presentation and during the PICU stay was significantly higher in Canada for both chest radiographs and blood tests (P < .001). The use of antibiotics was significantly higher in Canada both before (60% vs 28%; P < .001) and during (72% vs 33%; P < .0001) the PICU stay. The duration of ventilatory support, median length of stay, and rate of PICU readmission were similar in the 2 centers.

CONCLUSION

Important differences in the management of children with severe bronchiolitis were observed during both prehospital transport and PICU treatment. Less invasive management resulted in similar outcomes with in fewer complications.

Clinical Examination Does Not Predict Response to Albuterol in Ventilated Infants With Bronchiolitis

OBJECTIVE

Bronchiolitis is a common respiratory infection in infants that is sometimes treated with albuterol. Response to albuterol is determined by clinical assessment, but this subjective determination is potentially unreliable. In this study, we compared providers' clinical assessment of response to albuterol with the measurement of response by pulmonary mechanics in intubated, sedated, and ventilated infants.

DESIGN

Before and 20 minutes following racemic albuterol therapy, a nurse, respiratory therapist, and physician performed simultaneous examinations and assessed response to albuterol in a population of intubated infants with bronchiolitis. Measurements of ventilator-derived pulmonary mechanics were obtained at these same times.

SETTING

This study was conducted in a PICU of a children's hospital.

PATIENTS

Seventy-five paired clinical assessments were made in 25 infants who were intubated and mechanically ventilated for severe bronchiolitis.

INTERVENTIONS

Pulmonary function measurements and clinical assessments before and after administration of albuterol.

MEASUREMENTS AND MAIN RESULTS

Response to albuterol was defined using a threshold of improvement in respiratory system resistance from baseline. Nine children (36%) had greater than 20% change and were deemed responders. Providers' discrimination of response was poor. The positive predictive values of nurses, respiratory therapists, and physicians were 38%, 25%, and 25%, respectively, and the negative predictive values were 67%, 54%, and 59%, respectively. Overall accuracy was 44% for nurses, 40% for respiratory therapists, and 48% for physicians. When comparing separate assessments of wheezing, aeration, and expiratory time, there was poor agreement between groups of providers in all variables (κ < 0.4 for each).

CONCLUSIONS

A provider's clinical assessment was not a reliable method for determining response to albuterol in children with bronchiolitis. Without assessment of pulmonary mechanics, caution should be used in classifying children with bronchiolitis as responders to albuterol.

Human Respiratory Syncytial Virus: Infection and Pathology

The human respiratory syncytial virus (hRSV) is by far the major cause of acute lower respiratory tract infections (ALRTIs) worldwide in infants and children younger than 2 years. The overwhelming number of hospitalizations due to hRSV-induced ALRTI each year is due, at least in part, to the lack of licensed vaccines against this virus. Thus, hRSV infection is considered a major public health problem and economic burden in most countries. The lung pathology developed in hRSV-infected individuals is characterized by an exacerbated proinflammatory and unbalanced Th2-type immune response. In addition to the adverse effects in airway tissues, hRSV infection can also cause neurologic manifestations in the host, such as seizures and encephalopathy. Although the origins of these extrapulmonary symptoms remain unclear, studies with patients suffering from neurological alterations suggest an involvement of the inflammatory response against hRSV. Furthermore, hRSV has evolved numerous mechanisms to modulate and evade the immune response in the host. Several studies have focused on elucidating the interactions between hRSV virulence factors and the host immune system, to rationally design new vaccines and therapies against this virus. Here, we discuss about the infection, pathology, and immune response triggered by hRSV in the host.

Predicting Appropriate Admission of Bronchiolitis Patients in the Emergency Department: Rationale and Methods

BACKGROUND

In young children, bronchiolitis is the most common illness resulting in hospitalization. For children less than age 2, bronchiolitis incurs an annual total inpatient cost of $1.73 billion. Each year in the United States, 287,000 emergency department (ED) visits occur because of bronchiolitis, with a hospital admission rate of 32%-40%. Due to a lack of evidence and objective criteria for managing bronchiolitis, ED disposition decisions (hospital admission or discharge to home) are often made subjectively, resulting in significant practice variation. Studies reviewing admission need suggest that up to 29% of admissions from the ED are unnecessary. About 6% of ED discharges for bronchiolitis result in ED returns with admission. These inappropriate dispositions waste limited health care resources, increase patient and parental distress, expose patients to iatrogenic risks, and worsen outcomes. Existing clinical guidelines for bronchiolitis offer limited improvement in patient outcomes. Methodological shortcomings include that the guidelines provide no specific thresholds for ED decisions to admit or to discharge, have an insufficient level of detail, and do not account for differences in patient and illness characteristics including co-morbidities. Predictive models are frequently used to complement clinical guidelines, reduce practice variation, and improve clinicians' decision making. Used in real time, predictive models can present objective criteria supported by historical data for an individualized disease management plan and guide admission decisions. However, existing predictive models for ED patients with bronchiolitis have limitations, including low accuracy and the assumption that the actual ED disposition decision was appropriate. To date, no operational definition of appropriate admission exists. No model has been built based on appropriate admissions, which include both actual admissions that were necessary and actual ED discharges that were unsafe.

OBJECTIVE

The goal of this study is to develop a predictive model to guide appropriate hospital admission for ED patients with bronchiolitis.

METHODS

This study will: (1) develop an operational definition of appropriate hospital admission for ED patients with bronchiolitis, (2) develop and test the accuracy of a new model to predict appropriate hospital admission for an ED patient with bronchiolitis, and (3) conduct simulations to estimate the impact of using the model on bronchiolitis outcomes.

RESULTS

We are currently extracting administrative and clinical data from the enterprise data warehouse of an integrated health care system. Our goal is to finish this study by the end of 2019.

CONCLUSIONS

This study will produce a new predictive model that can be operationalized to guide and improve disposition decisions for ED patients with bronchiolitis. Broad use of the model would reduce iatrogenic risk, patient and parental distress, health care use, and costs and improve outcomes for bronchiolitis patients.

Prevention of Respiratory Syncytial Virus Infection: From Vaccine to Antibody

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract disease in infants and young children. Initial efforts to develop a vaccine to prevent RSV lower respiratory tract disease in children were halted because of serious adverse events that occurred when children were infected with RSV following vaccination, including vaccine-related deaths. Subsequently, a major focus for researchers was to understand what led to these adverse events. Investment in a vaccine for RSV continues, and new strategies are under development. Success to prevent RSV disease was met by the development of immunoprophylaxis, first with intravenous immunoglobulin and then with recombinant monoclonal antibody. The story of immunoprophylaxis for RSV includes the first-in-class use of antibody technology for infectious disease, and palivizumab currently remains the only way to prevent serious lower respiratory tract disease due to RSV infection.

Biomarkers of respiratory syncytial virus (RSV) infection: specific neutrophil and cytokine levels provide increased accuracy in predicting disease severity

Despite fundamental advances in the research on respiratory syncytial virus (RSV) since its initial identification almost 60 years ago, recurring failures in developing vaccines and pharmacologic strategies effective in controlling the infection have allowed RSV to become a leading cause of global infant morbidity and mortality. Indeed, the burden of this infection on families and health care organizations worldwide continues to escalate and its financial costs are growing. Furthermore, strong epidemiologic evidence indicates that early-life lower respiratory tract infections caused by RSV lead to the development of recurrent wheezing and childhood asthma. While some progress has been made in the identification of reliable biomarkers for RSV bronchiolitis, a "one size fits all" biomarker capable of accurately and consistently predicting disease severity and post-acute outcomes has yet to be discovered. Therefore, it is of great importance on a global scale to identify useful biomarkers for this infection that will allow pediatricians to cost-effectively predict the clinical course of the disease, as well as monitor the efficacy of new therapeutic strategies.

Viral Specific Factors Contribute to Clinical Respiratory Syncytial Virus Disease Severity Differences in Infants

Background

There is a wide range of severity of respiratory syncytial viral (RSV) disease in previously healthy infants. Host factors have been well demonstrated to contribute to disease severity differences. However the possibility of disease severity differences being produced by factors intrinsic to the virus itself has rarely been studied.

Methods

Low-passage isolates of RSV collected prospectively from infants with different degrees of RSV disease severity were evaluated in vitro, holding host factors constant, so as to assess whether isolates induced phenotypically different cytokine/chemokine concentrations in a human lung epithelial cell line. Sixty-seven RSV isolates from previously healthy infants (38 hospitalized for acute RSV infection (severe disease) and 29 never requiring hospitalization (mild disease)) were inoculated into A549, lung epithelial cells at precisely controlled, low multiplicity of infection to mimic natural infection. Cultures were evaluated at 48 hours, 60 hours, and 72 hours to evaluate area under the curve (AUC) cytokine/chemokine induction.

Results

Cells infected with isolates from severely ill infants produced higher mean concentrations of all cytokine/chemokines tested (IL-1α, IL-6, IL-8 and RANTES) at all-time points tested. RSV isolates collected from infants with severe disease induced significantly higher AUCIL-8 and AUCRANTES secretion in infected cultures than mild disease isolates (p=0.028 and p=0.019 respectively). IL-8 and RANTES concentrations were 4 times higher at 48 hours for these severely ill infant isolates. Additionally, 38 isolates were evaluated at all-time points for quantity of virus. RSV concentration significantly correlated with both IL-8 and RANTES at all-time points. Neither cytokine/chemokine concentrations nor RSV concentrations were associated with RSV subgroup.

Discussion

Infants’ RSV disease severity differences may be due in part to intrinsic viral strain-specific characteristics.

Variability of intensive care management for children with bronchiolitis

OBJECTIVE

To determine the extent of variability in testing and treatment of children with bronchiolitis requiring intensive care.

METHODS

This prospective, multicenter observational study included 16 academic children's hospitals across the United States during the 2007 to 2010 fall and winter seasons. The study included children<2 years old hospitalized with bronchiolitis who required admission to the ICU and/or continuous positive airway pressure (CPAP) within 24 hours of admission. Among the 2207 enrolled patients with bronchiolitis, 342 children met inclusion criteria. Clinical data and nasopharyngeal aspirates were collected.

RESULTS

Respiratory distress severity scores and intraclass correlation coefficients were calculated. The study patients' median age was 2.6 months, and 59% were male. Across the 16 sites, the median respiratory distress severity score was 5.1 (interquartile range: 4.5-5.4; P<.001). The median value of the percentages for all sites using CPAP was 15% (range: 3%-100%), intubation was 26% (range: 0%-100%), and high-flow nasal cannula (HFNC) was 24% (range: 0%-94%). Adjusting for site-specific random effects (as well as children's demographic characteristics and severity of bronchiolitis), the intraclass correlation coefficient for CPAP and/or intubation was 21% (95% confidence interval: 8-44); for HFNC, it was 44.7% (95% confidence interval: 24-67).

CONCLUSIONS

In this multicenter study of children requiring intensive care for bronchiolitis, we identified substantial institutional variability in testing and treatment, including use of CPAP, intubation, and HFNC. These differences were not explained by between-site differences in patient characteristics, including severity of illness. Further research is needed to identify best practices for intensive care interventions for this major cause of pediatric hospitalization.

The Argentina Premature Asthma and Respiratory Team (APART): objectives, design, and recruitment results of a prospective cohort study of viruses and wheezing in very low birth weight infants

Background

Asthma and wheezing account for a substantial disease burden around the world. Very low birth weight (VLBW, <1500 grams) infants are at an increased risk for the development of severe acute respiratory illness (ARI) and recurrent wheeze/asthma. The role of respiratory viruses in asthma predisposition in premature infants is not well understood. Preliminary evidence suggests that infection with human rhinovirus (RV) early in life may contribute to greater burden of asthma later in life.

Methods

A prospective cohort study of premature VLBW infants from Buenos Aires, Argentina, was enrolled year-round during a three-year period in the neonatal intensive care unit and followed during every ARI and with monthly well visits during the first year of life. Longitudinal follow-up up until age five years is ongoing.

Results

This report describes the objectives, design, and recruitment results of this prospective cohort. Two hundred and five patients were enrolled from August 2011 through January 2014, and follow-up is ongoing. A total of 319 ARI episodes were observed from August 2011 to July 2014, and 910 well visits occurred during this time period.

Conclusions

The Argentina Premature Asthma and Respiratory Team (APART) is a unique cohort consisting of over 200 patients and over 1200 specimens who have been and will continue to be followed intensively from NICU discharge to capture baseline risk factors and every ARI, with interceding well visits during the first year of life, as well as longitudinal follow-up to age 5 years for asthma and atopy outcomes.

Risk factors associated with death in patients with severe respiratory syncytial virus infection

BACKGROUND

Respiratory syncytial virus (RSV) infection is an important cause of viral respiratory tract infection in children. This retrospective study describes the clinical characteristics of severe RSV infection and determines the risk factors for death.

METHODS

Patients were identified through a review of all patients discharged with a diagnosis of RSV lower respiratory tract infection and admitted to hospital in the pediatric intensive care unit (PICU) of a tertiary medical center between July 1, 2001 and June 30, 2010. The medical and demographic variables were recorded and analyzed.

RESULTS

The 186 RSV-positive patients admitted to the PICU had a median age of 5.3 months (interquartile range 2.3-12.4 months) and included 129 boys and 57 girls. Among them, 134 had at least one underlying disease: prematurity in 92, neurological disease in 57, bronchopulmonary dysplasia in 40, congenital heart disease in 26, hematological malignancies in 11, and Down's syndrome in nine patients. The 10 patients who died from RSV-related causes had a median age of 20.8 months (interquartile range 6.6-89.2 months) and all had a comorbidity. In multivariate analysis, the risk factors for death in severe RSV infection were Down's syndrome (odds ratio 7.20, 95% confidence interval 1.13-45.76; p = 0.036) and nosocomial RSV infection (odds ratio 4.46, 95% confidence interval 1.09-18.27; p = 0.038).

CONCLUSION

Down's syndrome and nosocomial RSV infection are significantly associated with death in severe RSV infections. Clinicians should be alert to these conditions.

Central nervous system alterations caused by infection with the human respiratory syncytial virus

Worldwide, the human respiratory syncytial virus (hRSV) is the leading cause of infant hospitalization because of acute respiratory tract infections, including severe bronchiolitis and pneumonia. Despite intense research, to date there is neither vaccine nor treatment available to control hRSV disease burden globally. After infection, an incubation period of 3-5 days is usually followed by symptoms, such as cough and low-grade fever. However, hRSV infection can also produce a larger variety of symptoms, some of which relate to the individual's age at infection. Indeed, infants can display severe symptoms, such as dyspnea and chest wall retractions. Upon examination, crackles and wheezes are also common features that suggest infection by hRSV. Additionally, infection in infants younger than 1 year is associated with several non-specific symptoms, such as failure to thrive, periodic breathing or apnea, and feeding difficulties that usually require hospitalization. Recently, neurological symptoms have also been associated with hRSV respiratory infection and include seizures, central apnea, lethargy, feeding or swallowing difficulties, abnormalities in muscle tone, strabismus, abnormalities in the CSF, and encephalopathy. Here, we discuss recent findings linking the neurological, extrapulmonary effects of hRSV with infection and functional impairment of the CNS.

Respiratory Syncytial Virus: pathology, therapeutic drugs and prophylaxis

Human Respiratory Syncytial Virus (hRSV) is the leading cause of lower respiratory tract diseases, affecting particularly newborns and young children. This virus is able to modulate the immune response, generating a pro-inflammatory environment in the airways that causes obstruction and pulmonary alterations in the infected host. To date, no vaccines are available for human use and the first vaccine that reached clinical trials produced an enhanced hRSV-associated pathology 50 years ago, resulting in the death of two children. Currently, only two therapeutic approaches have been used to treat hRSV infection in high risk children: 1. Palivizumab, a humanized antibody against the F glycoprotein that reduces to half the number of hospitalized cases and 2. Ribavirin, which fails to have a significant therapeutic effect. A major caveat for these approaches is their high economical cost, which highlights the need of new and affordable therapeutic or prophylactic tools to treat or prevents hRSV infection. Accordingly, several efforts are in progress to understand the hRSV-associated pathology and to characterize the immune response elicited by this virus. Currently, preclinical and clinical trials are being conducted to evaluate safety and efficacy of several drugs and vaccines, which have shown promising results. In this article, we discuss the most important advances in the development of drugs and vaccines, which could eventually lead to better strategies to treat or prevent the detrimental inflammation triggered by hRSV infection.

Diagnosis and treatment of bronchiolitis in Finnish and Swedish children's hospitals

AIM

There is no widely accepted consensus on the diagnosis and treatment of bronchiolitis. This study describes current practices in Finnish and Swedish hospitals.

METHODS

A questionnaire on the diagnosis and treatment of bronchiolitis in children below 2 years of age was sent to all Finnish and Swedish hospitals providing inpatient care for children. All 22 Finnish hospitals answered, covering 100% of the <12-month-old population and 21 of the 37 Swedish hospitals responded, covering 74%.

RESULTS

The mean upper age limit for bronchiolitis was 12.7 months in Finnish hospitals and 12.5 months in Swedish hospitals. In both, laboured breathing, chest retractions and fine crackles were highlighted as the main clinical findings, followed by prolonged expiration. The mean value for the lowest acceptable saturation in room air was 94% in Finnish hospitals and 93% in Swedish hospitals. The most important factors influencing hospitalisation were young age, desaturation and inability to take oral fluids. Finnish doctors preferred intravenous routes, and Swedish doctors preferred nasogastric tubes for supplementary feeding. The first-line drug therapy was inhaled racemic adrenaline in Finland and inhaled levo-adrenaline in Sweden.

CONCLUSION

The diagnosis and treatment of bronchiolitis is fairly similar in Finnish and Swedish hospitals.

A systematic review of predictive modeling for bronchiolitis

PURPOSE

Bronchiolitis is the most common cause of illness leading to hospitalization in young children. At present, many bronchiolitis management decisions are made subjectively, leading to significant practice variation among hospitals and physicians caring for children with bronchiolitis. To standardize care for bronchiolitis, researchers have proposed various models to predict the disease course to help determine a proper management plan. This paper reviews the existing state of the art of predictive modeling for bronchiolitis. Predictive modeling for respiratory syncytial virus (RSV) infection is covered whenever appropriate, as RSV accounts for about 70% of bronchiolitis cases.

METHODS

A systematic review was conducted through a PubMed search up to April 25, 2014. The literature on predictive modeling for bronchiolitis was retrieved using a comprehensive search query, which was developed through an iterative process. Search results were limited to human subjects, the English language, and children (birth to 18 years).

RESULTS

The literature search returned 2312 references in total. After manual review, 168 of these references were determined to be relevant and are discussed in this paper. We identify several limitations and open problems in predictive modeling for bronchiolitis, and provide some preliminary thoughts on how to address them, with the hope to stimulate future research in this domain.

CONCLUSIONS

Many problems remain open in predictive modeling for bronchiolitis. Future studies will need to address them to achieve optimal predictive models.

Respiratory syncytial virus induces leukotriene C4 synthase expression in bronchial epithelial cells

BACKGROUND AND OBJECTIVE

Respiratory syncytial virus (RSV) results in acute wheezing in infants and is frequently associated with recurrent wheezing. Although RSV-induced wheezing clinically resembles that of asthma, corticosteroids are not equivalently effective in RSV-associated wheezing. The study sought to determine the mechanisms of RSV-induced wheezing by establishing an in vitro model of RSV-infected human bronchial epithelial cells (16-HBEC).

METHODS

Leukotriene C4 synthase (LTC4 S) messenger RNA (mRNA) expression in 16-HBEC was detected using fluorescence quantitative polymerase chain reaction, and the relative level of LTC4 S mRNA was expressed as quotient cycle threshold (qCt) based on the threshold cycle number value compared with that of β-actin. Cysteinyl leukotrienes (CysLT) in culture supernatant were measured by enzyme-linked immunosorbent assay. RSV-infected 16-HBEC was incubated with gradient concentration of budesonide (BUD) to assess its effects on LTC4 S expression and CysLT secretion.

RESULTS

RSV infection resulted in increased LTC4 S mRNA expression between 48 and 96 h post-infection. High level of CysLT was detected in the supernatant of RSV-infected 16-HBEC. BUD at concentrations of 10(-10) to 10(-5) mol/L did not significantly alter LTC4 S mRNA expression.

CONCLUSIONS

RSV infection upregulated LTC4 S expression in HBEC leading to increased CysLT secretion. Such induction was not attenuated by BUD, suggesting that CysLT might contribute to the pathogenesis of RSV-induced wheezing.

Overuse of bronchodilators and steroids in bronchiolitis of different severity: bronchiolitis-study of variability, appropriateness, and adequacy

BACKGROUND

In the management of acute bronchiolitis there is a generalised use of treatments that have not been shown to be useful or efficacious in clinical studies. The objective of this study was to determine the appropriateness in the treatment of acute bronchiolitis of different severity within different clinical care settings.

METHODS

This is a cross-sectional, descriptive study of 5647 cases of acute bronchiolitis in 91 Spanish hospitals and primary care centres. We classified the appropriateness of the treatments according to the recommendations of a consensus conference.

RESULTS

There was an inappropriate use of treatments in 58.3% of the cases during the acute phase and in 45.4% during the maintenance phase. There was a generalised use of inhaled beta 2 agonists, regardless of the severity of the patients (hospitalised patients 69.3%, emergency care 63.2% and ambulatory 64.1%). Adrenaline was used in 30.1% of hospitalised cases and in 80.2% of intensive care patients. Systemic corticosteroids were not only used in one-third of hospitalised patients but also in 25.8% of ambulatory cases.

CONCLUSIONS

In acute bronchiolitis in Spain there is a wide use of treatments that are not recommended by the available clinical practice guidelines. Beta 2 agonist bronchodilators and corticosteroids are widely used and maintained, regardless of the severity of the patients.

Bronchodilators for bronchiolitis

BACKGROUND

Bronchiolitis is an acute, viral lower respiratory tract infection affecting infants and is sometimes treated with bronchodilators.

OBJECTIVES

To assess the effects of bronchodilators on clinical outcomes in infants (0 to 12 months) with acute bronchiolitis.

SEARCH METHODS

We searched CENTRAL 2013, Issue 12, MEDLINE (1966 to January Week 2, 2014) and EMBASE (1998 to January 2014).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing bronchodilators (other than epinephrine) with placebo for bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two authors assessed trial quality and extracted data. We obtained unpublished data from trial authors.

MAIN RESULTS

We included 30 trials (35 data sets) representing 1992 infants with bronchiolitis. In 11 inpatient and 10 outpatient studies, oxygen saturation did not improve with bronchodilators (mean difference (MD) -0.43, 95% confidence interval (CI) -0.92 to 0.06, n = 1242). Outpatient bronchodilator treatment did not reduce the rate of hospitalization (11.9% in bronchodilator group versus 15.9% in placebo group, odds ratio (OR) 0.75, 95% CI 0.46 to 1.21, n = 710). Inpatient bronchodilator treatment did not reduce the duration of hospitalization (MD 0.06, 95% CI -0.27 to 0.39, n = 349).Effect estimates for inpatients (MD -0.62, 95% CI -1.40 to 0.16) were slightly larger than for outpatients (MD -0.25, 95% CI -0.61 to 0.11) for oximetry. Oximetry outcomes showed significant heterogeneity (I(2) statistic = 81%). Including only studies with low risk of bias had little impact on the overall effect size of oximetry (MD -0.38, 95% CI -0.75 to 0.00) but results were close to statistical significance.In eight inpatient studies, there was no change in average clinical score (standardized MD (SMD) -0.14, 95% CI -0.41 to 0.12) with bronchodilators. In nine outpatient studies, the average clinical score decreased slightly with bronchodilators (SMD -0.42, 95% CI -0.79 to -0.06), a statistically significant finding of questionable clinical importance. The clinical score outcome showed significant heterogeneity (I(2) statistic = 73%). Including only studies with low risk of bias reduced the heterogeneity but had little impact on the overall effect size of average clinical score (SMD -0.22, 95% CI -0.41 to -0.03).Sub-analyses limited to nebulized albuterol or salbutamol among outpatients (nine studies) showed no effect on oxygen saturation (MD -0.19, 95% CI -0.59 to 0.21, n = 572), average clinical score (SMD -0.36, 95% CI -0.83 to 0.11, n = 532) or hospital admission after treatment (OR 0.77, 95% CI 0.44 to 1.33, n = 404).Adverse effects included tachycardia, oxygen desaturation and tremors.

AUTHORS' CONCLUSIONS

Bronchodilators such as albuterol or salbutamol do not improve oxygen saturation, do not reduce hospital admission after outpatient treatment, do not shorten the duration of hospitalization and do not reduce the time to resolution of illness at home. Given the adverse side effects and the expense associated with these treatments, bronchodilators are not effective in the routine management of bronchiolitis. This meta-analysis continues to be limited by the small sample sizes and the lack of standardized study design and validated outcomes across the studies. Future trials with large sample sizes, standardized methodology across clinical sites and consistent assessment methods are needed to answer completely the question of efficacy.

Apnea in children hospitalized with bronchiolitis

OBJECTIVE

To identify risk factors for inpatient apnea among children hospitalized with bronchiolitis.

METHODS

We enrolled 2207 children, aged <2 years, hospitalized with bronchiolitis at 16 sites during the winters of 2007 to 2010. Nasopharyngeal aspirates (NPAs) were obtained on all subjects, and real-time polymerase chain reaction was used to test NPA samples for 16 viruses. Inpatient apnea was ascertained by daily chart review, with outcome data in 2156 children (98%). Age was corrected for birth <37 weeks. Multivariable logistic regression was performed to identify independent risk factors for inpatient apnea.

RESULTS

Inpatient apnea was identified in 108 children (5%, 95% confidence interval [CI] 4%-6%). Statistically significant, independent predictors of inpatient apnea included: corrected ages of <2 weeks (odds ratio [OR] 9.67) and 2 to 8 weeks (OR 4.72), compared with age ≥ 6 months; birth weight <2.3 kg (5 pounds; OR 2.15), compared with ≥ 3.2 kg (7 pounds); caretaker report of previous apnea during this bronchiolitis episode (OR 3.63); preadmission respiratory rates of <30 (OR 4.05), 30 to 39 (OR 2.35) and >70 (OR 2.26), compared with 40 to 49; and having a preadmission room air oxygen saturation <90% (OR 1.60). Apnea risk was similar across the major viral pathogens.

CONCLUSIONS

In this prospective, multicenter study of children hospitalized with bronchiolitis, inpatient apnea was associated with younger corrected age, lower birth weight, history of apnea, and preadmission clinical factors including low or high respiratory rates and low room air oxygen saturation. Several bronchiolitis pathogens were associated with apnea, with similar apnea risk across the major viral pathogens.

Quality improvement research in pediatric hospital medicine and the role of the Pediatric Research in Inpatient Settings (PRIS) network

Pediatric hospitalists care for many hospitalized children in community and academic settings, and they must partner with administrators, other inpatient care providers, and researchers to assure the reliable delivery of high-quality, safe, evidence-based, and cost-effective care within the complex inpatient setting. Paralleling the growth of the field of pediatric hospital medicine is the realization that innovations are needed to address some of the most common clinical questions. Some of the unique challenges facing pediatric hospitalists include the lack of evidence for treating common conditions, children with chronic complex conditions, compressed time frame for admissions, and the variety of settings in which hospitalists practice. Most pediatric hospitalists are engaged in some kind of quality improvement (QI) work as hospitals provide many opportunities for QI activity and innovation. There are multiple national efforts in the pediatric hospital medicine community to improve quality, including the Children's Hospital Association (CHA) collaboratives and the Value in Pediatrics Network (VIP). Pediatric hospitalists are also challenged by the differences between QI and QI research; understanding that while improving local care is important, to provide consistent quality care to children we must study single-center and multicenter QI efforts by designing, developing, and evaluating interventions in a rigorous manner, and examine how systems variations impact implementation. The Pediatric Research in Inpatient Setting (PRIS) network is a leader in QI research and has several ongoing projects. The Prioritization project and Pediatric Health Information System Plus (PHIS+) have used administrative data to study variations in care, and the IIPE-PRIS Accelerating Safe Sign-outs (I-PASS) study highlights the potential for innovative QI research methods to improve care and clinical training. We address the importance, current state, accomplishments, and challenges of QI and QI research in pediatric hospital medicine; define the role of the PRIS Network in QI research; describe an exemplary QI research project, the I-PASS Study; address challenges for funding, training and mentorship, and publication; and identify future directions for QI research in pediatric hospital medicine.

Acute bronchiolitis

Bronchiolitis is the most common lower respiratory tract infection to affect infants and toddlers. High-risk patients include infants younger than 3 months, premature infants, children with immunodeficiency, children with underlying cardiopulmonary or neuromuscular disease, or infants prone to apnea, severe respiratory distress, and respiratory failure. Bronchiolitis is a self-limited disease in healthy infants and children. Treatment is usually symptomatic, and the goal of therapy is to maintain adequate oxygenation and hydration. Use of a high-flow nasal cannula is becoming common for children with severe bronchiolitis.

Lack of effect of bovine lactoferrin in respiratory syncytial virus replication and clinical disease severity in the mouse model

BACKGROUND

Lactoferrin (LF) is a glycoprotein present in human milk with known antimicrobial effects. In vitro, LF has demonstrated antiviral activity against respiratory syncytial virus (RSV). We sought to assess the effect of bovine (b)LF in RSV replication, lung inflammation and function, cytokine profiles and clinical disease in an in vivo murine model.

METHODS

Female BALB/c mice were inoculated with 10(7)PFU RSV A2 or 10% EMEM. bLF or placebo (DPBS) were administered once or twice daily by oral gavage or intraperitoneal (IP) injection at doses ranging from 2 to 10mg/animal/day, from 48h before until 96h post-RSV inoculation. Bronchoalveolar lavage (BAL), whole lung and serum samples were harvested on day 5 post-inoculation to asses RSV loads, lung inflammation and cytokine concentrations. Weight loss, airway obstruction and disease severity were assessed daily in all groups.

RESULTS

On day 5 post-inoculation BAL RSV loads, lung inflammation and serum innate, Th1, Th2 and Th17 cytokine concentrations showed no differences between RSV infected mice treated with bLF and RSV infected but untreated mice independent of bLF dosing and administration route (p>0.05). In addition, all bLF groups showed similar weight loss, degree of airway obstruction, and disease severity scores on days 1-5 post-inoculation which was comparable to infected untreated mice (p>0.05) but higher than uninfected controls.

CONCLUSIONS

Administration of oral or IP bLF at different doses did not demonstrate antiviral activity or significant effects on disease severity in the RSV mouse model. Whether these observations could be extrapolated to infants at risk for RSV infection needs to be further explored.

Decreasing unnecessary utilization in acute bronchiolitis care: results from the value in inpatient pediatrics network

BACKGROUND

Acute viral bronchiolitis is the most common diagnosis resulting in hospital admission in pediatrics. Utilization of non-evidence-based therapies and testing remains common despite a large volume of evidence to guide quality improvement efforts.

OBJECTIVE

Our objective was to reduce utilization of unnecessary therapies in the inpatient care of bronchiolitis across a diverse network of clinical sites.

METHODS

We formed a voluntary quality improvement collaborative of pediatric hospitalists for the purpose of benchmarking the use of bronchodilators, steroids, chest radiography, chest physiotherapy, and viral testing in bronchiolitis using hospital administrative data. We shared resources within the network, including protocols, scores, order sets, and key bibliographies, and established group norms for decreasing utilization.

RESULTS

Aggregate data on 11,568 hospitalizations for bronchiolitis from 17 centers was analyzed for this report. The network was organized in 2008. By 2010, we saw a 46% reduction in overall volume of bronchodilators used, a 3.4 dose per patient absolute decrease in utilization (95% confidence interval [CI] 1.4-5.8). Overall exposure to any dose of bronchodilator decreased by 12 percentage points as well (95% CI 5%-25%). There was also a statistically significant decline in chest physiotherapy usage, but not for steroids, chest radiography, or viral testing.

CONCLUSIONS

Benchmarking within a voluntary pediatric hospitalist collaborative facilitated decreased utilization of bronchodilators and chest physiotherapy in bronchiolitis.

Acute care utilization due to hospitalizations for pediatric lower respiratory tract infections in British Columbia, Canada

BACKGROUND

Pediatric LRTI hospitalizations are a significant burden on patients, families, and healthcare systems. This study determined the burden of pediatric LRTIs on hospital settings in British Columbia and the benefits of prevention strategies as they relate to healthcare resource demand.

METHODS

LRTI inpatient episodes for patients <19 years of age during 2008-2010 were extracted from the BC Discharge Abstract Database. The annual number of acute care beds required to treat pediatric LRTIs was estimated. Sub-analyses determined the burden due to infants <1 year of age and high-risk infants. Population projections were used to forecast LRTI hospitalizations and the effectiveness of public health initiatives to reduce the incidence of LRTIs to 2020 and 2030.

RESULTS

During 2008-2010, LRTI as the primary diagnosis accounted for 32.0 and 75.9% hospitalizations for diseases of the respiratory system in children <19 years of age and infants <1 year of age, respectively. Infants <1 year of age accounted for 47 and 77% hospitalizations due to pediatric LRTIs and pediatric LRTI hospitalizations specifically due to respiratory syncytial virus (RSV), respectively. The average length of stay was 3.1 days for otherwise healthy infants <1 year of age and 9.1 days for high-risk infants (P <0.0001). 73.1% pediatric LRTI hospitalizations occurred between November and April. Over the study timeframe, 19.6 acute care beds were required on average to care for pediatric LRTIs which increased to 64.0 beds at the peak of LRTI hospitalizations. Increases in LRTI bed-days of 5.5 and 16.2% among <19 year olds by 2020 and 2030, respectively, were predicted. Implementation of appropriate prevention strategies could cause 307 and 338 less LRTI hospitalizations in <19 year olds in 2020 and 2030, respectively.

CONCLUSION

Pediatric LRTI hospitalizations require significant use of acute care infrastructure particularly between November and April. Population projections show the burden may increase in the next 20 years, but implementation of effective public health prevention strategies may contribute to reducing the acute care demand and to supporting efforts for overall pediatric healthcare sustainability.

Use of continuous positive airway pressure during stabilisation and retrieval of infants with suspected bronchiolitis

AIM

Infants with viral bronchiolitis are often hospitalised with a proportion requiring respiratory support. The aim of this review was to examine the use of nasal prong continuous positive airway pressure (CPAP) as a management strategy for infants with a diagnosis of bronchiolitis, who required stabilisation and transport to a tertiary centre.

METHOD

A retrospective audit of infants with bronchiolitis requiring CPAP during transport between January 2003 and June 2007.

RESULTS

Nasal CPAP was initiated in 54 infants with 51 of these (34 ex-preterm, 17 term) subsequently continuing on CPAP during retrieval. Mean CPAP pressure was 7 cmH(2)O. Oxygenation improved between stabilisation and the end of retrieval (P < 0.01). During retrieval, there was no significant increase in transcutaneous CO(2), no infant required endotracheal ventilation and no adverse events were noted. Five infants were intubated within the first 24 h of admission at the receiving hospital.

CONCLUSION

This review demonstrated that use of nasal prong CPAP to transport infants with bronchiolitis was a safe management strategy in those with moderate to severe disease severity.

Risk factors for admission in children with bronchiolitis from pediatric emergency department observation unit

BACKGROUND

Patients with bronchiolitis are increasingly being admitted to emergency department observation units (EDOUs) but often require subsequent hospitalization. To better identify ED patients who should be directly admitted to the hospital rather than the EDOU, the predictors of admission must be identified.

OBJECTIVES

The objective of this study was to determine the predictors of subsequent hospital admission from the EDOU in infants and young children with bronchiolitis.

METHOD

This was a retrospective cohort study of patients younger than 2 years admitted to an EDOU with bronchiolitis between April 1, 2003, and March 31, 2007. Univariate analysis was followed by logistic regression to identify the significant predictors of hospital admission from the EDOU.

RESULTS

There were 325 patients in the study: 67% were younger than 6 months, and 60% were male. Eighty-five (26%) were admitted to the hospital from the EDOU. Predictors for admission from the EDOU included parental report of poor feeding or increased work of breathing, oxygen saturation less than 93%, or ED treatment with racemic epinephrine (Vaponephrine) and intravenous fluids (IVFs).

CONCLUSION

Patients with a history of increased work of breathing or oxygen saturation less than 93% and ED treatment with IVFs are at high risk for admission from the EDOU to the hospital. Direct admission to the hospital from the ED should be considered for these patients, particularly patients treated with IVFs and having an oxygen saturation less than 93% in the ED.

A pilot, randomized, controlled clinical trial of lucinactant, a peptide-containing synthetic surfactant, in infants with acute hypoxemic respiratory failure

OBJECTIVE

Inhibition of surfactant function and abnormal surfactant synthesis lead to surfactant dysfunction in children with acute hypoxemic respiratory failure. We evaluated whether intratracheal lucinactant, a synthetic, peptide-containing surfactant, was safe and well-tolerated in infants with acute hypoxemic respiratory failure, and assessed its effects on clinical outcomes.

METHODS AND MAIN RESULTS

Infants ≤ 2 yrs of age with acute hypoxemic respiratory failure were enrolled in a phase II, double-blind, multinational, placebo-controlled randomized trial across 36 pediatric intensive care units. Infants requiring mechanical ventilation with persistent hypoxemia meeting acute lung injury criteria were randomized to receive intratracheal lucinactant (175 mg/kg) or air placebo. One retreatment was allowed 12-24 hrs after initial dosing if hypoxemia persisted. Peri-dosing tolerability of intratracheal lucinactant and adverse experiences were assessed. Mechanical ventilation duration was analyzed using analysis of variance. The Cochran-Mantel-Haenszel test was used for categorical variables.We enrolled 165 infants (84 lucinactant; 81 placebo) with acute hypoxemic respiratory failure. There were no significant differences in baseline subject characteristics, with the exception of a lower positive end-expiratory pressure and higher tidal volume in placebo subjects. The incidence of transient peri-dosing bradycardia and desaturation was significantly higher in the lucinactant treatment group. There were no statistical differences between groups for other adverse events or mortality. Oxygenation improved in infants randomized to receive lucinactant as indicated by fewer second treatments (67% lucinactant vs. 81% placebo, p = .02) and a trend in improvement in partial pressure of oxygen in arterial blood to fraction of inspired oxygen from eligibility to 48 hrs after dose (p = .06). There was no significant reduction in duration of mechanical ventilation with lucinactant (geometric least square means: 4.0 days lucinactant vs. 4.5 days placebo; p = .254). In a subset of infants (n = 22), the duration of mechanical ventilation in children with acute lung injury (partial pressure of oxygen in arterial blood to fraction of inspired oxygen >200) was significantly shorter with lucinactant (least square means: 2.4 days lucinactant vs. 4.3 days placebo; p = .006).

CONCLUSIONS

In mechanically ventilated infants with acute hypoxemic respiratory failure, treatment with intratracheal lucinactant appeared to be generally safe. An improvement in oxygenation and a significantly reduced requirement for retreatment suggests that lucinactant might improve lung function in infants with acute hypoxemic respiratory failure.

A comparative study of respiratory syncytial virus (RSV) prophylaxis in premature infants within the Canadian Registry of Palivizumab (CARESS)

We examined the dosing regimens, compliance, and outcomes of premature infants who received palivizumab within the Canadian Registry of Palivizumab (CARESS). Infants receiving ≥1 dose of palivizumab during the 2006-2011 respiratory syncytial virus (RSV) seasons were recruited across 30 sites. Respiratory illness events were captured monthly. Infants ≤32 completed weeks gestational age (GA) (Group 1) were compared to 33-35 completed weeks GA infants (Group 2) following prophylaxis. In total, 6,654 patients were analyzed (Group 1, n = 5,183; Group 2, n = 1,471). The mean GA was 29.9 ± 2.9 versus 34.2 ± 2.2 weeks for Groups 1 and 2, respectively. Group differences were significant (all p-values <0.05) for the following: proportion of males, Caucasians, siblings, multiple births, maternal smoking, smoking during pregnancy, household smokers, >5 household individuals, birth weight, and enrolment age. Overall, infants received 92.6 % of expected injections. Group 1 received significantly more injections, but a greater proportion of Group 2 received injections within recommended intervals. The hospitalization rates were similar for Groups 1 and 2 for respiratory illness (4.7 % vs. 3.7 %, p = 0.1) and RSV (1.5 % vs. 1.4 %, p = 0.3). Neither the time to first respiratory illness [hazard ratio = 0.9, 95 % confidence interval (CI) 0.7-1.2, p = 0.5] nor to first RSV hospitalization (hazard ratio = 1.3, 95 % CI 0.8-2.2, p = 0.3) were different. Compliance with RSV prophylaxis is high. Despite the higher number of palivizumab doses in infants ≤32 completed weeks GA, the two groups' respiratory illness and RSV-positive hospitalization rates were similar.

Capnometry as a predictor of admission in bronchiolitis

OBJECTIVES

Bronchiolitis is a dynamic condition, and predicting clinical deterioration can be difficult. The objective of this study was to determine whether capnometry readings among bronchiolitic children admitted to the hospital are significantly different from those discharged from the emergency department.

METHODS

We prospectively studied a convenience sample of children younger than 24 months with clinical bronchiolitis. A single end-tidal CO2 (ETCO2) reading was taken before treatment, and a clinical work of breathing score was assigned to each patient. Treating physicians and nurses were blinded to capnometry readings. The decision to admit was based on the judgment of the attending physician. Descriptive statistics and appropriate hypothesis testing were performed. A receiver operating characteristic curve was constructed for the association between admission and capnometry readings. The α was set at 0.05 for all comparisons.

RESULTS

One hundred five children with bronchiolitis were included for study. Capnometry readings for admitted (mean, 32.6 mm Hg; 95% confidence interval [CI], 30.3-34.9 mm Hg) and discharged (mean 31.4 mm Hg; 95% CI 29.8-33.0 mm Hg) bronchiolitic children were not significantly different. Capnometry readings for low (mean, 31.7 mm Hg; 95% CI, 29.5-33.8 mm Hg), intermediate (mean, 32.1 mm Hg; 95% CI, 30.1-34.1 mm Hg), and high (mean, 30.5 mm Hg; 95% CI, 19.3-41.7 mm Hg) work of breathing (score) ranges were not significantly different.

CONCLUSIONS

Capnometry readings are not useful in predicting admission for children younger than 2 years with clinical bronchiolitis. There are no significant differences in capnometry readings among bronchiolitic children with low, medium, and high work of breathing scores.

Prospective multicenter study of children with bronchiolitis requiring mechanical ventilation

OBJECTIVE

To identify factors associated with continuous positive airway pressure (CPAP) and/or intubation for children with bronchiolitis.

METHODS

We performed a 16-center, prospective cohort study of hospitalized children aged <2 years with bronchiolitis. For 3 consecutive years from November 1 until March 31, beginning in 2007, researchers collected clinical data and a nasopharyngeal aspirate from study participants. We oversampled children from the ICU. Samples of nasopharyngeal aspirate were tested by polymerase chain reaction for 18 pathogens.

RESULTS

There were 161 children who required CPAP and/or intubation. The median age of the overall cohort was 4 months; 59% were male; 61% white, 24% black, and 36% Hispanic. In the multivariable model predicting CPAP/intubation, the significant factors were: age <2 months (odds ratio [OR] 4.3; 95% confidence interval [CI] 1.7-11.5), maternal smoking during pregnancy (OR 1.4; 95% CI 1.1-1.9), birth weight <5 pounds (OR 1.7; 95% CI 1.0-2.6), breathing difficulty began <1 day before admission (OR 1.6; 95% CI 1.2-2.1), presence of apnea (OR 4.8; 95% CI 2.5-8.5), inadequate oral intake (OR 2.5; 95% CI 1.3-4.3), severe retractions (OR 11.1; 95% CI 2.4-33.0), and room air oxygen saturation <85% (OR 3.3; 95% CI 2.0-4.8). The optimism-corrected c-statistic for the final model was 0.80.

CONCLUSIONS

In this multicenter study of children hospitalized with bronchiolitis, we identified several demographic, historical, and clinical factors that predicted the use of CPAP and/or intubation, including children born to mothers who smoked during pregnancy. We also identified a novel subgroup of children who required mechanical respiratory support <1 day after respiratory symptoms began.

Management of acute bronchiolitis in emergency wards in Spain: variability and appropriateness analysis (aBREVIADo Project)

Most patients with acute bronchiolitis have a mild course and only require outpatient care. However, some of them have to go to emergency departments, because they have respiratory distress or feeding problems. There, they frequently receive diagnostic and therapeutic procedures. We want to know the variability and appropriateness of these procedures. A cross-sectional study (October 2007 to March 2008) was carried out on 2,430 diagnosed cases of bronchiolitis in hospital emergency departments, which required no hospitalization. An analysis of the appropriateness of the treatments was made in 2,032 cases gathered in ten departments with at least 100 cases, using as criterion the recommendations of a consensus conference. We estimated the adjusted percentages of each department. Most of the bronchiolitis were mild, in spite that they underwent multiple diagnostic and therapeutic procedures. In the acute phase, different treatments were used: inhaled beta 2 agonists (61.4%), antipyretics (17.1%), oral steroids (11.3%), and nebulized adrenaline (9.3%). In the maintenance phase, the most common treatments were: inhaled beta 2 agonists (50.5%), oral steroids (17%), oral beta 2 agonists (14.9%), and antibiotics (6.1%). The 64% of the treatments used in the acute phase and the 55.9% in the maintenance phase were considered inappropriate in the appropriateness analysis; a great heterogeneity among centers was found.

CONCLUSIONS

There are discrepancies between clinical practice and evidence-based management of bronchiolitis in Spanish emergency departments. Inappropriate treatments were used in more than half of patients. The wide variation between centers shows the influence of local prescribing habits and reveals the scope for improvement.

Impact of a bronchiolitis clinical care pathway on treatment and hospital stay

Bronchiolitis is a common lower respiratory tract infection of infancy where management has varied considerably in the past. The aim of the present study was to determine whether patient treatment and outcomes changed after introduction of a clinical care pathway. Infants aged up to 6 months admitted to hospital with bronchiolitis were identified as part of an annual audit of bronchiolitis management between winters 2003/2004 and 2009/2010. The primary outcome, duration of stay (DOS), was compared before and after the clinical pathway was introduced before the winter 2005/2006. There were 328 infants identified, mean age 75 days, respiratory syncitial virus was detected in 89%. After the clinical pathway was introduced, the proportion of infants prescribed salbutamol fell from 50% to 8% (p < 0.001) and ipratropium bromide from 38% to 0% (p < 0.001) but the proportion prescribed antibiotics was unchanged. The median DOS was 79 h prior to the clinical pathway and 66 h afterwards (p = 0.010) but there was no difference in days where supplemental oxygen or nasogastric feeding was required.

CONCLUSIONS

A clinical pathway for the management of acute bronchiolitis can be implemented in the hospital setting and the conservative approach, in particular not prescribing bronchodilators, is not associated with prolonged duration of stay.