Treatment of bronchiolitis: state of the art

Oxygen Saturation Targets in Infants Hospitalized With Bronchiolitis: A Multicenter Cohort Study

OBJECTIVES

To examine 2 hospital oxygen saturation target policies and clinical outcomes in infants hospitalized with bronchiolitis.

METHODS

This multicenter cohort study used data collected from a randomized clinical trial of infants aged 4 weeks to 24 months, hospitalized with bronchiolitis at children's and community hospitals from 2016 to 2019. We modeled the association between hospital oxygen saturation target policy, either 90% while awake and 88% while asleep (90%/88%) or 90% while awake and asleep (90%/90%), and clinical outcomes.

RESULTS

A total of 162 infants were enrolled at 4 hospitals using a 90%/88% oxygen saturation target and 67 infants at 2 hospitals using a 90%/90% target policy. No significant differences between the 90%/88% group and 90%/90% groups were observed for time to discharge (adjusted hazard ratio, 0.83; 95% confidence interval [CI], 0.61-1.14; P = .25), initiation of supplemental oxygen (adjusted odds ratio [aOR], 0.98; 95% CI, 0.47-2.02; P = .95), time to discontinuation of supplemental oxygen (adjusted hazard ratio, 0.75; 95% CI, 0.44-1.27; P = .28), revisits (aOR, 1.38; 95% CI, 0.52-3.71; P = .52), and parent days missed from work (aOR, 2.41; 95% CI, 0.90-6.41; P = .08). Three infants in the 90%/88% group and none in the 90%/90% group were transferred to the ICU.

CONCLUSIONS

Among infants hospitalized with bronchiolitis, clinical outcomes were similar between a hospital oxygen saturation target policy of 90% while awake and 88% while asleep compared with 90% while awake and asleep. These findings may inform the design of future trials of oxygen saturation targets in bronchiolitis hospital care.

Update on the Role of High-Flow Nasal Cannula in Infants with Bronchiolitis

Bronchiolitis (BR), a lower respiratory tract infection mainly caused by respiratory syncytial virus (RSV), can be very severe. Presently, adequate nutritional support and oxygen therapy remain the only interventions recommended to treat patients with BR. For years, mild BR cases were treated with noninvasive standard oxygen therapy (SOT), i.e., with cold and poorly or totally non-humidified oxygen delivered by an ambient headbox or low-flow nasal cannula. Children with severe disease were intubated and treated with invasive mechanical ventilation (IMV). To improve SOT and overcome the disadvantages of IMV, new measures of noninvasive and more efficient oxygen administration have been studied. Bi-level positive air way pressure (BiPAP), continuous positive airway pressure (CPAP), and high-flow nasal cannula (HFNC) are among them. For its simplicity, good tolerability and safety, and the good results reported in clinical studies, HFNC has become increasingly popular and is now widely used. However, consistent guidelines for initiation and discontinuation of HFNC are lacking. In this narrative review, the role of HFNC to treat infants with BR is discussed. An analysis of the literature showed that, despite its widespread use, the role of HFNC in preventing respiratory failure in children with BR is not precisely defined. It is not established whether it can offer greater benefits compared to SOT and when and in which infants it can replace CPAP or BiPAP. The analysis of the results clearly indicates the need for multicenter studies and official guidelines. In the meantime, HFNC can be considered a safe and effective method to treat children with mild to moderate BR who do not respond to SOT.

A two-tiered high-flow nasal cannula approach to bronchiolitis was associated with low admission rate to intensive care and no adverse outcomes

AIM

We aimed to describe the characteristics and outcomes of infants with bronchiolitis who received high-flow nasal cannula oxygen (HFNC) following a two-tiered approach.

METHODS

This retrospective study included 211 infants below 12 months of age needing oxygen therapy for bronchiolitis, between 2012 and 2017, on the general paediatric ward of the tertiary Paediatric Hospital of Padova, Italy. HFNC was used as first-line therapy for moderate to severe disease and as rescue therapy for deterioration on low-flow oxygen.

RESULTS

Median age was 61 days (IQR 31-126), and 57.3% were males. HFNC was used as first-line therapy in 35/211 (16.6%) infants and as rescue in 73/176 (41.5%) patients on low-flow oxygen. Overall 9/211 patients (4.3%) were admitted to intensive care, representing a HFNC failure of 9/108 (8.3%). Intensive care admissions did not significantly differ between initial low-flow oxygen therapy and HFNC (8/176, 4.5% versus 1/35, 2.8%, proportion difference 1.7%, 95%CI -10.2 to 6.7), or between initial and rescue HFNC (1/35, 2.8% versus 8/73, 10.9%; proportion difference 8.1%, 95%CI -4.5 to 18). Only two patients developed air leak and were treated conservatively.

CONCLUSION

A two-tiered approach to HFNC use in bronchiolitis was associated with low intensive care admissions and no adverse outcomes.

'Rational use of high-flow therapy in infants with bronchiolitis. What do the latest trials tell us?' A Paediatric Research in Emergency Departments International Collaborative perspective

Bronchiolitis is the most common reason for infants to be hospitalised. Over the past decade, the use of high-flow nasal cannulae (HFNC) therapy has increased markedly and it is now utilised not only in the intensive care unit setting but in general paediatric wards and emergency departments. The aim of this systematic review was to summarise and critique the current evidence-base for the use of HFNC in infants with bronchiolitis. We searched Ovid Medline, OvidEmbase, PubMed, Cinahl, Cochrane Library, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials for systematic reviews and randomised controlled trials of HFNC therapy in infants with bronchiolitis from 1 January 2000 to 27 June 2018. We identified four randomised controlled trials (n = 1891) of HFNC in infants with bronchiolitis: three of these studies involved infants treated in emergency departments and inpatient paediatric wards in Spain, Australia and New Zealand, and one study involved infants treated in paediatric intensive care units in France. The findings of this review suggest that HFNC should be used as a rescue treatment for hypoxaemic infants who have not responded to standard sub nasal oxygen therapy. The use of HFNC for work of breathing in the absence of hypoxaemia, and severe disease, is not currently supported by the evidence, and should only be considered in the context of an appropriate research trial.

Respiratory Support during Bronchiolitis Due to One Virus versus More Than One Virus: An Observational Study

Bronchiolitis is common during infancy and frequently leads to pediatric intensive care unit (PICU) admission. This study aimed to determine if there is a difference in the duration of respiratory support when bronchiolitis is due to one virus or more than one virus. This is a retrospective, observational study of cases admitted to PICU with confirmed bronchiolitis. There were 306 cases analyzed, 70% (215/306) were infected by a single virus and 30% (91/306) were infected with more than one virus. Both groups had similar duration of respiratory support and PICU length of stay (LOS). Hospital LOS was longer for the group with more than one virus.

Prophylactic digoxin treatment reduces IL-17 production in vivo in the neonatal calf and moderates RSV-associated disease

Respiratory syncytial virus (RSV) is a leading cause of morbidity and mortality in human infants. Bovine RSV infection of neonatal calves is pathologically and immunologically similar to RSV infection in infants, and is therefore a useful preclinical model for testing novel therapeutics. Treatment of severe RSV bronchiolitis relies on supportive care and may include use of bronchodilators and inhaled or systemic corticosteroids. Interleukin-17A (IL-17) is an inflammatory cytokine that plays an important role in neutrophil recruitment and activation. IL-17 is increased in children and rodents with severe RSV infection; and in calves with severe BRSV infection. It is currently unclear if IL-17 and Th17 immunity is beneficial or detrimental to the host during RSV infection. Digoxin was recently identified to selectively inhibit IL-17 production by antagonizing its transcription factor, retinoid-related orphan receptor γ t (RORγt). Digoxin inhibits RORγt binding to IL-17 and Th17 associated genes, and suppresses IL-17 production in vitro in human and murine leukocytes and in vivo in rodent models of autoimmune disease. We demonstrate here that in vitro and in vivo digoxin treatment also inhibits IL-17 production by bovine leukocytes. To determine the role of IL-17 in primary RSV infection, calves were treated prophylactically with digoxin and infected with BRSV. Digoxin treated calves demonstrated reduced signs of clinical illness after BRSV infection, and reduced lung pathology compared to untreated control calves. Digoxin treatment did not adversely affect virus shedding or lung viral burden, but had a significant impact on pulmonary inflammatory cytokine expression on day 10 post infection. Together, our results suggest that exacerbated expression of IL-17 has a negative impact on RSV disease, and that development of specific therapies targeting Th17 immunity may be a promising strategy to improve disease outcome during severe RSV infection.

Bronchiolitis in children: The Saudi initiative of bronchiolitis diagnosis, management, and prevention (SIBRO)

Bronchiolitis is the leading cause of admissions in children less than two years of age. It has been recognized as highly debated for many decades. Despite the abundance of literature and the well-recognized importance of palivizumab in the high risk groups, and despite the existence of numerous, high-quality, recent guidelines on bronchiolitis, the number of admissions continues to increase. Only supportive therapy and few therapeutic interventions are evidence based and proved to be effective. Since Respiratory Syncytial Virus (RSV) is the major cause of bronchiolitis, we will focus on this virus mostly in high risk groups like the premature babies and children with chronic lung disease and cardiac abnormalities. Further, the prevention of RSV with palivizumab in the high risk groups is effective and well known since 1998; we will discuss the updated criteria for allocating infants to this treatment, as this medication is expensive and should be utilized in the best condition. Usually, diagnosis of bronchiolitis is not challenging, however there has been historically no universally accepted and validated scoring system to assess the severity of the condition. Severe RSV, especially in high risk children, is unique because it can cause serious respiratory sequelae. Currently there is no effective curative treatment for bronchiolitis. The utility of different therapeutic interventions is worth a discussion.

Using a high-flow nasal cannula provided superior results to low-flow oxygen delivery in moderate to severe bronchiolitis

AIM

An observational study was carried out on infants with moderate to severe bronchiolitis to compare the clinical outcomes following treatment with a high-flow nasal cannula (HFNC) or standard low-flow oxygen.

METHODS

We enrolled subjects below 12 months of age who were affected by their first bronchiolitis episode. Non-formal randomisation, based on HFNC availability, was used to assign subjects to either the HFNC or standard oxygen groups. Respiratory rate, respiratory effort and the ability to feed were compared between the two groups at enrolment and at regular time points. The oxygen requirements and the length of hospital stay were also analysed.

RESULTS

Overall, 36 of the 40 enrolled infants completed the study: 18 treated with HFNC (mean age 3.2 months, range 1.2-5.4 months) and 18 with low-flow oxygen delivery (mean age 3.6 months, range 1.3-5.0 months). Improvements in the respiratory rate, respiratory effort and ability to feed were significantly faster in the HFNC group than the low-flow oxygen group. The HNFC group needed oxygen supplementation for two days less than the other group and hospital stays were three days shorter.

CONCLUSION

HFNC provided superior clinical outcomes for infants under 12 months with moderate-to-severe bronchiolitis compared to low-flow oxygen.

Post-bronchiolitis Use of Asthma Medication: A Prospective 1-year Follow-up Study

BACKGROUND

Our aim was to evaluate the association between viral findings during bronchiolitis and the use of asthma controller medication (primary outcome) and systemic corticosteroids (secondary outcome) during the first post-bronchiolitis year.

METHODS

We enrolled 408 children hospitalized for bronchiolitis at <24 months of age in a prospective, 3-center, 1-year follow-up study in Finland. Viruses were detected with polymerase chain reaction in nasopharyngeal aspirates. The parents underwent a structured interview during hospitalization. Twelve months later, the use of asthma medication was asked in a structured questionnaire. Multivariable logistic regression was used for statistical analysis.

RESULTS

In total, 365 (89%) children completed the 1-year follow-up. The use of long-term asthma controller medication was highest in the rhinovirus-positive group (61% vs. 15% in respiratory syncytial virus-positive group; adjusted odd ratios, 7.5; 95% confidence interval: 3.7-15.3), followed by children negative for both respiratory syncytial virus and rhinovirus (36%; adjusted odd ratios, 2.6; 95% confidence interval: 1.3-5.3). Likewise, rhinovirus etiology was associated with more courses of systemic corticosteroids during the follow-up. The main findings were similar in a subset of infants aged <12 months with first wheezing.

CONCLUSIONS

Children hospitalized for rhinovirus-positive bronchiolitis used long-term asthma controller medication more often than those hospitalized for rhinovirus-negative bronchiolitis during first year after hospitalization.

Latest options for treatment of bronchiolitis in infants

Bronchiolitis is the most frequent pathology associated with lower respiratory tract infection in newborns and young infants. The treatment of bronchiolitis is essentially supportive therapy for respiratory distress, hypoxia and dehydration. To date, no specific antiviral drug is used on a routine basis for the treatment of RSV infections. Currently, the only antiviral drug approved for the infection is ribavirin; however, its use is limited due to adverse side effects and the risks it poses to healthcare providers. Moreover, several drugs have been routinely administered for years in infants with acute RSV bronchiolitis, even if their efficacy is often not confirmed by clinical evidence, and studies on emerging antiviral drugs are still ongoing. In the present paper we review the recent literature about the drugs used during acute bronchiolitis and we summarize the main recommendations of national and international guidelines and the latest options for the treatment of bronchiolitis.

Nasal irrigation with saline solution significantly improves oxygen saturation in infants with bronchiolitis

AIM

Published guidelines do not recommend nasal irrigation in bronchiolitis, but it is common practice in Italy, despite a lack of data on its benefits or adverse effects. This single-blind, multicentre, randomised controlled trial compared nasal irrigation using either isotonic 0.9% sodium chloride or hypertonic 3% sodium chloride with simple supportive care in infants with bronchiolitis.

METHODS

We randomly assigned 133 infants up one year of age, who were admitted to the emergency department with bronchiolitis and an oxygen saturation (SpO2) of between 88 and 94%, to the isotonic (n = 47), hypertonic (n = 44) or standard care (n = 42) groups. Variations in SpO2 and the wheeze, air exchange, respiratory rate, muscle use (WARM) respiratory distress score were recorded at zero, five, 15, 20 and 50 minutes.

RESULTS

Five minutes after the intervention, the median SpO2 value (95%) in the isotonic group was higher than both the hypertonic (94%) and the standard care (93%) groups. The differences between the isotonic and standard treatment groups were statistically significant at each time point, while the hypertonic group only reached significantly higher values after 50 minutes. However, the WARM score did not improve.

CONCLUSION

A single nasal irrigation with saline solution significantly improved oxygen saturation in infants with bronchiolitis.

Salt, chloride, bleach, and innate host defense

Salt provides 2 life-essential elements: sodium and chlorine. Chloride, the ionic form of chlorine, derived exclusively from dietary absorption and constituting the most abundant anion in the human body, plays critical roles in many vital physiologic functions, from fluid retention and secretion to osmotic maintenance and pH balance. However, an often overlooked role of chloride is its function in innate host defense against infection. Chloride serves as a substrate for the generation of the potent microbicide chlorine bleach by stimulated neutrophils and also contributes to regulation of ionic homeostasis for optimal antimicrobial activity within phagosomes. An inadequate supply of chloride to phagocytes and their phagosomes, such as in CF disease and other chloride channel disorders, severely compromises host defense against infection. We provide an overview of the roles that chloride plays in normal innate immunity, highlighting specific links between defective chloride channel function and failures in host defense.

What's new in clinical solid organ transplantation by 2013

Innovative and exciting advances in the clinical science in solid organ transplantation continuously realize as the results of studies, clinical trials, international conferences, consensus conferences, new technologies and discoveries. This review will address to the full spectrum of news in transplantation, that verified by 2013. The key areas covered are the transplantation activity, with particular regards to the donors, the news for solid organs such as kidney, pancreas, liver, heart and lung, the news in immunosuppressive therapies, the news in the field of tolerance and some of the main complications following transplantation as infections and cancers. The period of time covered by the study starts from the international meetings held in 2012, whose results were published in 2013, up to the 2013 meetings, conferences and consensus published in the first months of 2014. In particular for every organ, the trends in numbers and survival have been reviewed as well as the most relevant problems such as organ preservation, ischemia reperfusion injuries, and rejections with particular regards to the antibody mediated rejection that involves all solid organs. The new drugs and strategies applied in organ transplantation have been divided into new way of using old drugs or strategies and drugs new not yet on the market, but on phase Ito III of clinical studies and trials.

Inter-society consensus document on treatment and prevention of bronchiolitis in newborns and infants

Acute bronchiolitis is the leading cause of lower respiratory tract infection and hospitalization in children less than 1 year of age worldwide. It is usually a mild disease, but some children may develop severe symptoms, requiring hospital admission and ventilatory support in the ICU. Infants with pre-existing risk factors (prematurity, bronchopulmonary dysplasia, congenital heart diseases and immunodeficiency) may be predisposed to a severe form of the disease. Clinical diagnosis of bronchiolitis is manly based on medical history and physical examination (rhinorrhea, cough, crackles, wheezing and signs of respiratory distress). Etiological diagnosis, with antigen or genome detection to identify viruses involved, may have a role in reducing hospital transmission of the infection. Criteria for hospitalization include low oxygen saturation (<90-92%), moderate-to-severe respiratory distress, dehydration and presence of apnea. Children with pre-existing risk factors should be carefully assessed.To date, there is no specific treatment for viral bronchiolitis, and the mainstay of therapy is supportive care. This consists of nasal suctioning and nebulized 3% hypertonic saline, assisted feeding and hydration, humidified O2 delivery. The possible role of any pharmacological approach is still debated, and till now there is no evidence to support the use of bronchodilators, corticosteroids, chest physiotherapy, antibiotics or antivirals. Nebulized adrenaline may be sometimes useful in the emergency room. Nebulized adrenaline can be useful in the hospital setting for treatment as needed. Lacking a specific etiological treatment, prophylaxis and prevention, especially in children at high risk of severe infection, have a fundamental role. Environmental preventive measures minimize viral transmission in hospital, in the outpatient setting and at home. Pharmacological prophylaxis with palivizumab for RSV bronchiolitis is indicated in specific categories of children at risk during the epidemic period. Viral bronchiolitis, especially in the case of severe form, may correlate with an increased incidence of recurrent wheezing in pre-schooled children and with asthma at school age.The aim of this document is to provide a multidisciplinary update on the current recommendations for the management and prevention of bronchiolitis, in order to share useful indications, identify gaps in knowledge and drive future research.

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.