Conferencia de Consenso sobre bronquiolitis aguda (I): metodología y recomendaciones

Effect of prenatal and postnatal exposure to tobacco in the development of acute bronchiolitis in the first two years of life

INTRODUCTION

Environmental exposure to tobacco increases the risk of respiratory disease in infants. However, the impact of maternal smoking on the development of acute bronchiolitis has hardly been assessed. The aim of this study was to determine the incidence of acute bronchiolitis and to analyse the effect of prenatal and postnatal maternal smoking on the development of this disease.

PATIENTS AND METHODS

A prospective, observational study was performed on healthy newborns from a third level hospital born between October 2015 and February 2016. Questionnaires were completed by the mothers at discharge from maternity and followed-up for two years. These collected information about prenatal and postnatal smoking, lifestyle, family and personal history, and the development of bronchiolitis. A bivariate and multivariate logistic regression analysis was performed.

RESULTS

A total of 223 newborns were included, of whom 13.9% were exposed to tobacco smoking during gestation, 21.4% in the postnatal period, and 12.4% in both times. The incidence of bronchiolitis was 28.7% at one year of life, and 34.5% at two years. The multivariate analysis demonstrated that the prenatal and postnatal exposure to tobacco is an independent risk factor for the development of bronchiolitis (OR 4.38; 95% CI; 1.63-11.76), while prolonged breastfeeding is a protective factor (OR 0.13; 95% CI; 0.04-0.48). Other factors that were statistically significant were: atopic dermatitis (OR 2.91; 95% CI; 1.26-6.73), and gestational age (OR 1.42; 95% CI; 1.08-1.88).

CONCLUSIONS

Children exposed to prenatal and postnatal maternal smoking have a higher risk of suffering bronchiolitis. Reducing the smoking habit in women that intend to become pregnant must be a priority in preventive medicine.

[What is the optimal flow on starting high-flow oxygen therapy for bronchiolitis treatment in paediatric wards?]

INTRODUCTION

High-flow nasal cannula (HFNC) is a safe and effective treatment in bronchiolitis in paediatric wards. The optimal flow on starting HFNC is still unknown. The main aim of this study was to determine if there were differences in clinical outcome of patients according the initial flow.

METHODS

A prospective, observational and analytical study was conducted between 2014 and 2016 on infants admitted with bronchiolitis and who required HFNC. Two cohorts were established according to the initial flow: cohort1: flow 15L/min (HFNC-15), and cohort2: flow 10L/min (HFNC-10). Treatment failure was defined as the presentation of apnoea or the absence of clinical improvement in the first 12-24hours. Multivariate probabilistic models were built to identify predictive variables of treatment failure.

RESULTS

A total of 57 patients were included. The median age was 4months (IQR 2-13), and 54% received treatment with HFNC-10 and 46% with HFNC-15. In HFNC-15 cohort, respiratory rate (RR) decreased in the first hour, and in the HFNC-10 cohort in the first 6hours (P=.03). In HFNC-10 cohort, treatment failure rate was 71%, compared to 15% of HFNC-15 (P<.01). Admission to PICU was required in 35% of the HFNC-10 group vs 18% in HFNC-15 (P=.11). No adverse effects were found.

CONCLUSIONS

The use of HFNC 15L/min in bronchiolitis treatment in paediatric wards is safe and effective, achieves a faster improvement of respiratory rate and has a lower treatment failure rate.

Caracterización de una cohorte durante cinco años después de un episodio de bronquiolitis que requiere hospitalización en una clínica de tercer nivel de Bogotá, Colombia

Introducción. La Bronquiolitis secundaria al Virus Sincitial Respiratorio, se han asociado con episodios sibilantes recurrentes y desarrollo de asma, incluso en la adultez. Sin embargo, la relación entre estas patologías es controvertida, y aun no se conoce el comportamiento de este fenómeno en Colombia. El objetivo de este estudio fue describir la evolución clínica a cinco años, de los niños con antecedente de bronquiolitis que requirieron hospitalizaciónMateriales y métodos. Estudio descriptivo de cohorte retrospectiva de menores de dos años, con diagnóstico de Bronquiolitis atendidos en la Clínica Universitaria Colombia en los años 2008 a 2011 con seguimiento de hospitalizaciones por patologías respiratorias hasta el año 2016. Se revisaron 306 historias clínicas de pacientes y se analizaron características socio- demográficas, aislamientos virales y manejo farmacológico.Resultados. Los años con mayor número de hospitalizaciones por episodios sibilantes posterior al episodio bronquiolitis fueron el 2009 y 2011 con una incidencia acumulada de 15,6% y 9,9%. La edad promedio de hospitalización fue 6 meses y más frecuente en hombres. El virus sincital fue aislado con mayor frecuencia en los años de seguimiento, y la mayoría de los casos requirió manejo antibiótico; la ampicilina sulbactam (28,5%) y la ampicilina (22,6%).

A comparison of two clinical scores for bronchiolitis. A multicentre and prospective study conducted in hospitalised infants

BACKGROUND

There are a number of clinical scores for bronchiolitis but none of them are firmly recommended in the guidelines.

METHOD

We designed a study to compare two scales of bronchiolitis (ESBA and Wood Downes Ferres) and determine which of them better predicts the severity. A multicentre prospective study with patients <12 months with acute bronchiolitis was conducted. Each patient was assessed with the two scales when admission was decided. We created a new variable "severe condition" to determine whether one scale afforded better discrimination of severity. A diagnostic test analysis of sensitivity and specificity was made, with a comparison of the AUC. Based on the optimum cut-off points of the ROC curves for classifying bronchiolitis as severe we calculated new Se, Sp, LR+ and LR- for each scale in our sample.

RESULTS

201 patients were included, 66.7% males and median age 2.3 months (IQR=1.3-4.4). Thirteen patients suffered bronchiolitis considered to be severe, according to the variable severe condition. ESBA showed a Se=3.6%, Sp=98.1%, and WDF showed Se=46.2% and Sp=91.5%. The difference between the two AUC for each scale was 0.02 (95%CI: 0.01-0.15), p=0.72. With new cut-off points we could increase Se and Sp for ESBA: Se=84.6%, Sp=78.7%, and WDF showed Se=92.3% and Sp=54.8%; with higher LR.

CONCLUSIONS

None of the scales studied was considered optimum for assessing our patients. With new cut-off points, the scales increased the ability to classify severe infants. New validation studies are needed to prove these new cut-off points.

[High flow nasal cannula oxygen therapy in the treatment of acute bronchiolitis in neonates]

OBJECTIVE

To determine whether the availability of heated humidified high-flow nasal cannula (HFNC) therapy was associated with a decrease in need for mechanical ventilation in neonates hospitalised with acute bronchiolitis.

METHODS

A combined retrospective and prospective (ambispective) cohort study was performed in a type II-B Neonatal Unit, including hospitalised neonates with acute bronchiolitis after the introduction of HFNC (HFNC-period; October 2011-April 2015). They were compared with a historical cohort prior to the availability of this technique (pre-HFNC; January 2008-May 2011). The need for mechanical ventilation between the two study groups was analysed. Clinical parameters and technique-related complications were evaluated in neonates treated with HFNC.

RESULTS

A total of 112 neonates were included, 56 after the introduction of HFNC and 56 from the period before the introduction of HFNC. None of patients in the HFNC-period required intubation, compared with 3.6% of the patients in the pre-HFNC group. The availability of HFNC resulted in a significant decrease in the need for non-invasive mechanical ventilation (30.4% vs 10.7%; P=.01), with a relative risk (RR) of .353 (95% CI; .150-.829), an absolute risk reduction (ARR) of 19.6% (95% CI; 5.13 - 34.2), yielding a NNT of 5. In the HFNC-period, 22 patients received high flow therapy, and 22.7% (95% CI; 7.8 to 45.4) required non-invasive ventilation. Treatment with HFNC was associated with a significant decrease in heart rate (P=.03), respiratory rate (P=.01), and an improvement in the Wood-Downes Férres score (P=.00). No adverse effects were observed.

CONCLUSIONS

The availability of HFNC reduces the need for non-invasive mechanical ventilation, allowing a safe and effective medical management of neonates with acute bronchiolitis.

Hypoxaemia as a Mortality Risk Factor in Acute Lower Respiratory Infections in Children in Low and Middle-Income Countries: Systematic Review and Meta-Analysis

Objective

To evaluate the association between hypoxaemia and mortality from acute lower respiratory infections (ALRI) in children in low- and middle-income countries (LMIC).

Design

Systematic review and meta-analysis.

Study Selection

Observational studies reporting on the association between hypoxaemia and death from ALRI in children below five years in LMIC.

Data Sources

Medline, Embase, Global Health Library, Lilacs, and Web of Science to February 2015.

Risk of Bias Assessment

Quality In Prognosis Studies tool with minor adaptations to assess the risk of bias; funnel plots and Egger’s test to evaluate publication bias.

Results

Out of 11,627 papers retrieved, 18 studies from 13 countries on 20,224 children met the inclusion criteria. Twelve (66.6%) studies had either low or moderate risk of bias. Hypoxaemia defined as oxygen saturation rate (SpO2) <90% associated with significantly increased odds of death from ALRI (OR 5.47, 95% CI 3.93 to 7.63) in 12 studies on 13,936 children. An Sp02 <92% associated with a similar increased risk of mortality (OR 3.66, 95% CI 1.42 to 9.47) in 3 studies on 673 children. Sensitivity analyses (excluding studies with high risk of bias and using adjusted OR) and subgroup analyses (by: altitude, definition of ALRI, country income, HIV prevalence) did not affect results. Only one study was performed on children living at high altitude.

Conclusions

The results of this review support the routine evaluation of SpO2 for identifying children with ALRI at increased risk of death. Both a Sp02 value of 92% and 90% equally identify children at increased risk of mortality. More research is needed on children living at high altitude. Policy makers in LMIC should aim at improving the regular use of pulse oximetry and the availability of oxygen in order to decrease mortality from ALRI.

NIV-Helmet in Severe Hypoxemic Acute Respiratory Failure

Noninvasive ventilation (NIV) is a method to be applied in acute respiratory failure, given the possibility of avoiding tracheal intubation and conventional ventilation. A previous healthy 5-month-old boy developed low-grade intermittent fever, flu-like symptoms, and dry cough for 3 days. On admission, he showed severe respiratory distress with SpO₂/FiO₂ ratio of 94. Subsequent evaluation identified an RSV infection complicated with an increase of inflammatory parameters (reactive C protein 15 mg/dL). Within the first hour after NIV-helmet CPAP SpO₂/FiO₂ ratio increased to 157. This sustained improvement allowed the continuing of this strategy. After 102 h, he was disconnected from the helmet CPAP device. The NIV use in severe hypoxemic acute respiratory failure should be carefully monitored as the absence of clinical improvement has a predictive value in the need to resume to intubation and mechanical ventilation. We emphasize that SpO₂/FiO₂ ratio is a valuable monitoring instrument. Helmet interface use represents a more comfortable alternative for providing ventilatory support, particularly to small infants, which constitute a sensitive group within pediatric patients.

[Paediatric prescribing of anti-asthmatics in primary care in Castilla-León. Geographical variability]

INTRODUCTION AND OBJECTIVES

Asthma is one of the most prevalent chronic diseases with effective treatment in paediatrics. The aim of this study is to describe the paediatric prescribing of anti-asthmatics in Castilla-León, analyzing its geographic variability and temporal evolution.

MATERIAL AND METHODS

An analysis was made of prescriptions dispensed in pharmacies of R03 therapeutic subgroup (anti-asthmatic agents), and the active ingredients mepyramine and ketotifen, prescribed in children less than 14 years of age in the Castilla-León health service from 2005 to 2010 in Primary Care. Data is presented in prescribed daily doses per thousand inhabitants per day (PDHD) for each active ingredient being calculated raw rates and age-adjusted to the variables health area, type of health zone and year of study.

RESULTS

A total of 462,354 prescriptions of anti-asthmatic agents were dispensed to a population of 1,580,229 persons/year. There was wide variation between areas in the type and intensity of anti-asthmatic agents used, partly explained by differences in the prevalence of asthma. Montelukast predominated as controller drug in most of them (PDHD 3.1 to 7.7), being similar the consumption intensity in the three types of health zones (PDHD 4.7 to 4.8). The annual variability was low.

CONCLUSIONS

The study describes the paediatric prescribing pattern of anti-asthmatic agents in Castilla-León between 2005-2010. It shows wide geographical variation, as well as inadequacies regarding current recommendations of asthma treatment.

High flow therapy versus hypertonic saline in bronchiolitis: randomised controlled trial

OBJECTIVE

To demonstrate that heated humidified high-flow nasal cannula (HHHFNC) is superior to inhaled hypertonic saline solution (HSS) in improving respiratory distress in moderate bronchiolitis. In addition, it could improve comfort and reduce length of hospital stay (LOS) and admission to Paediatric Intensive Care Unit (PICU).

DESIGN

Randomised Clinical Trial from 1 October 2010 to 31 December 2012.

SETTING

Two urban secondary (no PICU available) paediatric hospitalisation units.

PATIENTS

Hospitalised children aged up to 6 months with moderate acute bronchiolitis (Respiratory Distress Assessment Instrument, RDAI ≥4).

INTERVENTION

Patients were randomised to HHHFNC or HSS. All of them received epinephrine as bronchodilator.

MAIN OUTCOMES

Primary outcome was difference in mean Respiratory Assessment Change Score (RACS) between both groups measured in six previously defined consecutive moments. Secondary outcomes were difference in mean comfort scores in this period, LOS and rate of PICU admission.

RESULTS

Seventy-five previously healthy patients were enrolled. Mean age was 2.4 months (95% CI 2.04 to 2.76). 43 were allocated to HSS group and 32 in HHHFNC. Data of 1 patient were lost, and 8 changed group over the study period. Intention-to-treat principle was applied. There were no significant differences in mean RACS and mean comfort scores between groups at the evaluation points. Median LOS or PICU admission rate were similar in both groups. No adverse events were observed.

CONCLUSIONS

HHHFNC was not superior to HSS in treatment of moderate acute bronchiolitis with respect to severity and comfort scores, LOS or PICU admission rate.

CLINICAL TRIAL REGISTRATION CLINICALTRIALSGOV IDENTIFIER

NCT01873144.

[Epidemiology, clinical features and medical interventions in children hospitalized for bronchiolitis]

OBJECTIVES

To describe the epidemiology, clinical characteristics and treatments prescribed in children with bronchiolitis admitted to our hospital.

MATERIAL AND METHODS

Observational, descriptive and prospective study of children younger than 18 months, admitted to Hospital Virgen de la Arrixaca of Murcia (Spain), with the diagnosis of bronchiolitis, during the season of maximum incidence (December 2008-April 2009).

RESULTS

A total of 235 infants were admitted, of whom 78.7% of them were aged 5 months or less. We found a positive correlation between the number of cigarettes smoked by their mothers during pregnancy and the number of hospitalization and oxygen therapy days. Children whose mothers were smokers at the time of their admission needed a greater number of oxygen therapy days. Also infants who were not breastfed needed oxygen therapy during more days. Just under one quarter (23.8%) of them had underlying diseases, with prematurity being the most frequent and a risk factor for the ongoing of oxygen therapy and hospital stay. The use of diagnostic tests, bronchodilators, corticosteroids and antibiotics was high. The onset of high temperature was associated with an increased use of antibiotics in outside and inside the hospital setting. An abnormal chest X-ray or a raised C-reactive protein was associated with a higher use of antibiotics. Respiratory Syncytial virus (RSV) was the main aetiological agent, followed by Rhinovirus, Bocavirus, Adenovirus and Metapneumovirus

CONCLUSIONS

The majority of hospital admissions due to bronchiolitis took place during the first months of life. Infants whose mothers smoked during pregnancy had a worse clinical outcome. Despite the availability of clinical practice guidelines in our area, the use of diagnostic tests and pharmacological treatment was high.

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.

[Consensus conference on acute bronchiolitis (v): prevention of acute bronchiolitis. Review of scientific evidence]

A review of the evidence on prevention of acute bronchiolitis is presented. Acute bronchiolitis prevention arises from three basic approaches: preventive treatment to reduce recurrent wheezing following an episode of acute bronchiolitis, preventive treatment to reduce the frequency and severity of RSV bronchiolitis in the population at risk (prematurity, bronchopulmonary dysplasia, congenital heart disease, etc.), and general preventive measures to reduce nosocomial infection with RSV. There is sufficient evidence on the lack of efficacy of inhaled corticosteroids, oral corticosteroids and montelukast. Intravenous RSV immunoglobulin has an unfavorable risk-benefit balance, particularly with the availability of monoclonal antibodies. Palivizumab is effective as preventive treatment of RSV infection in risk populations (high risk preterm infants and hemodynamically significant congenital heart disease), but not in the frequency and severity (ICU admission, need for mechanical ventilation and mortality) of the acute bronchiolitis. The benefits of palivizumab (less admissions) seem to be worth the adverse effects, but we do not know the cost-benefit ratio. The control and prevention measures of nosocomial transmission of RSV infection (isolation, hand washing, use of mask, gloves, cap and shoes) are based on indirect evidence.

[Consensus conference on acute bronchiolitis (VI): prognosis of acute bronchiolitis. Review of scientific evidence]

We present a review of the evidence on prognosis of acute bronchiolitis, risk factors for severe forms, symptom or severity scores and risk of post-bronchiolitis asthma. Documented risk factors of long stay or PICU admission in hospitalized patients are: bronchopulmonary dysplasia and/or chronic lung disease, prematurity, congenital heart disease and age less than 3 months. Other less well documented risk factors are: tobacco exposure, history of neonatal mechanical ventilation, breastfeeding for less than 4 months, viral co-infection and other chronic diseases. There are several markers of severity: toxic appearance, tachypnea, hypoxia, atelectasis or infiltrate on chest radiograph, increased breathing effort, signs of dehydration, tachycardia and fever. Although we have some predictive models of severity, none has shown sufficient predictive validity to recommend its use in clinical practice. While there are different symptom or severity scores, none has proven to be valid or accurate enough to recommend their preferable application in clinical practice. There seems to be a consistent and strong association between admission due to bronchiolitis and recurrent episodes of wheezing in the first five years of life. However it is unclear whether this association continues in subsequent years, as there are discordant data on the association between bronchiolitis and asthma.

[Consensus conference on acute bronchiolitis (II): epidemiology of acute bronchiolitis. Review of the scientific evidence]

A review of the evidence on epidemiology, risk factors, etiology and clinical-etiological profile of acute bronchiolitis is presented. The frequency estimates are very heterogeneous; in the population under two years the frequency of admission for bronchiolitis is between 1 and 3.5%, primary care consultations between 4 and 20% and emergency visits between 1 and 2%. The frequency of admissions for respiratory infection by respiratory syncytial virus in the risk population is: in premature infants < or =32 weeks of gestation between 4.4 and 18%, in patients with bronchopulmonary dysplasia between 7.3 and 42%, and in infants with congenital heart disease between 1.6 and 9.8%. The main risk factors are: prematurity, chronic lung disease or bronchopulmonary dysplasia, congenital heart disease and age less than 3-6 months at onset of the epidemic. Other factors are: older siblings or day care attendance, male gender, exposure to smoking, breastfeeding for less than 1-2 months and variables associated with lower socioeconomic status. Respiratory syncytial virus is the dominant etiological agent, constituting just over half the cases (median 56%; interval 27% to 73%). Other viruses implicated, in descending order of frequency, are rhinovirus, adenovirus, metapneumovirus, influenza viruses, parainfluenza, enterovirus and bocavirus. In studies with genomic detection techniques, between 20 and 25% of cases the virus involved is not identified and between 9% and 27% of cases have viral co-infection. Although respiratory syncytial virus bronchiolitis shows more wheezing and retractions, longer duration of respiratory symptoms and oxygen therapy and are associated with lower use of antibiotics. This pattern is associated with the younger age of the patients and does not help us to predict the etiology. In general, the etiological identification is not useful for the management of patients. However, in young infants (<3 months) with febrile bronchiolitis in the hospital environment, conservative management may help these patients and avoid diagnostic and therapeutic procedures.