Guideline sources The following summarized guidelines for the evaluation and management of bronchiolitis are prepared by our editorial team based on guidelines from the French Group for Pediatric Intensive Care and Emergencies (GFRUP 2023), the National Advisory Committee on Immunization (NACI 2022), the Canadian Paediatric Society (CPS 2021), the American Academy of Pediatrics (AAP 2020; 2018; 2014), the Paediatric Research in Emergency Departments International Collaborative (PREDICT 2019), the American College of Chest Physicians (ACCP 2018), the The Thoracic Society of Australia and New Zealand (TSANZ 2018), the Royal Australasian College of Physicians (RACP 2017), and the Society of Hospital Medicine (SHP 2013). 1 2 3 4 5 6 7 8 9 10 11 12 Calculator Calculator https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 1/13 6/29/23, 3:21 AM Bronchiolitis Pathway Modified Wood's Clinical Asthm Wang Respiratory Score WRS Guidelines 1. Screening and diagnosis Diagnosis: As per CPS 2021 guidelines, diagnose bronchiolitis clinically based on history and physical examination. E As per PREDICT 2019 guidelines, consider diagnosing bronchiolitis in infant patients with an upper respiratory tract infection followed by the onset of respiratory distress with fever and 1 of the following: cough tachypnea respiratory retractions diffuse crackles or wheeze on auscultation. C As per AAP 2014 guidelines, diagnose bronchiolitis and assess disease severity on the basis of history and physical examination. B 2. Classification and risk stratification Risk assessment: As per PREDICT 2019 guidelines, regard the following as risk factors for more serious illness: gestational age < 37 weeks chronological age at presentation < 10 weeks indigenous ethnicity breastfeeding for < 2 months exposure to cigarette smoke failure to thrive chronic pulmonary, heart, or neurological disease. B As per AAP 2014 guidelines, assess the following risk factors for severe disease when making decisions about the evaluation and management of patients with bronchiolitis: age < 12 weeks history of prematurity immunodeficiency underlying cardiopulmonary disease. B https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 2/13 6/29/23, 3:21 AM Bronchiolitis Pathway 3. Diagnostic investigations Clinical assessment: consider using clinical scores (such as the modified Wood's Clinical Asthma Score, the Wang score, and the Critical Bronchiolitis Score) for the initial assessment and follow- up. E Chest X-ray: As per GFRUP 2023 guidelines, avoid obtaining routine CXRs for the diagnosis of bronchiolitis. Obtain CXRs in patients with clinical signs of ventilatory complications or for the search for differential diagnosis. D As per CPS 2021 guidelines, do not obtain CXRs in typical cases of bronchiolitis. D As per PREDICT 2019 guidelines, do not obtain routine CXRs in infant patients with simple bronchiolitis. D As per RACP 2017 guidelines, do not obtain CXRs routinely for diagnosis of bronchiolitis in pediatric patients. D As per AAP 2014 guidelines, do not obtain CXRs routnely in patients with bronchiolitis diagnosed on the basis of history and physical examination. D As per SHP 2013 guidelines, do not obtain CXRs in pediatric patients with uncomplicated bronchiolitis. D Chest ultrasound: consider obtaining a lung ultrasound as an alternative to a CXR. E Laboratory tests: As per GFRUP 2023 guidelines, avoid obtaining virological tests in patients with bronchiolitis. D Show 2 more As per CPS 2021 guidelines, do not obtain blood tests and viral/bacterial cultures in typical cases of bronchiolitis. D As per PREDICT 2019 guidelines, do not obtain blood tests in infant patients presenting to the hospital and hospitalized with bronchiolitis. Do not obtain routine bacteriological testing of blood and urine. D Show 2 more As per AAP 2014 guidelines, do not obtain routne laboratory tests in patients with bronchiolitis diagnosed on the basis of history and physical examination. D 4. Respiratory support Oxygen monitoring: As per GFRUP 2023 guidelines, consider monitoring the trend of respiratory parameters and/or clinical scores to assess disease evolution. Avoid obtaining systematic monitoring of partial pressure of CO (and transcutaneous partial pressure of CO ). E As per CPS 2021 guidelines, obtain oxygen saturation monitoring in 1-24 months old hospitalized patients with bronchiolitis. Consider obtaining continuous saturation monitoring in https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 3/13 6/29/23, 3:21 AM Bronchiolitis Pathway high-risk patients in the acute phase of illness and intermittent monitoring or spot checks in lower-risk patients and clinically improving patients. E As per PREDICT 2019 guidelines, do not obtain routine continuous pulse oximetry in non- hypoxic (oxygen saturation 92%) infant patients not receiving oxygen or stable patients receiving oxygen. D As per AAP 2014 guidelines, avoid obtaining continuous pulse oximetry in infant and pediatric patients with bronchiolitis. D As per SHP 2013 guidelines, do not obtain continuous pulse oximetry routinely in pediatric patients with acute respiratory illness unless on supplemental oxygen. D Supplemental oxygen: As per PREDICT 2019 guidelines: Consider administering supplemental oxygen in the treatment of hypoxic (oxygen saturations < 92%) infant patients with bronchiolitis. C Administer oxygen supplementation in patients with uncomplicated bronchiolitis if the oxygen saturation level is sustained at a level < 92%. Discontinue oxygen therapy at oxygen saturation levels of 92%. B As per AAP 2014 guidelines, avoid administering supplemental oxygen if the oxyHgb saturation is > 90%. D Noninvasive ventilation: As per GFRUP 2023 guidelines, consider using a noninvasive ventilatory support protocol. E Consider initiating noninvasive ventilatory support over invasive ventilation as first-line treatment to reduce the work of breathing and improve clinical respiratory parameters. C Show 6 more Landmark trials: PARIS-2 In children aged 1-4 years requiring hospital admission for acute hypoxemic respiratory failure, high-flow oxygen therapy was inferior to standard oxygen therapy with respect to median length of hospital stay. Donna Franklin et al. JAMA. 2023 Jan 17. As per PREDICT 2019 guidelines: Consider administering high-flow nasal cannula oxygen in infant patients with bronchiolitis with hypoxia (oxygen saturation < 92%) in an inpatient setting. C Consider administering nasal CPAP therapy in the management of infant patients with bronchiolitis. C Invasive ventilation: insufficient evidence regarding the choice of invasive ventilation mode in infant patients with bronchiolitis. I https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 4/13 6/29/23, 3:21 AM Bronchiolitis Pathway 5. Medical management Setting of care (hospital admission): decide on hospital admission based on clinical judgment, factoring in the risk for progression to severe disease, respiratory status, ability to maintain adequate hydration and the family's ability to cope at home. E Setting of care (PICU admission): Consider using the following severity factors when deciding on pediatric ICU admission: presence of apneas hypercapnic acidosis with venous partial pressure of CO > 60 mmHg and/or pH < 7.30, if blood gas testing is available altered alertness and/or hypotonia hypoxemia with SpO < 92% under standard oxygen therapy (nasal cannulas at low-flow up to 2 L/min) significant increase in clinical work of breathing or respiratory fatigue. E Show 2 more Supportive care: As per GFRUP 2023 guidelines, consider preferring gastric enteral nutrition (or oral nutrition when possible) over IV hydration, regardless of the type of ventilatory support, in infant (< 12 months old) patients with bronchiolitis. Avoid thickening oral or enteral nutrition. E Show 6 more As per CPS 2021 guidelines: Initiate supportive care including hydration, minimal handling, gentle nasal suctioning and oxygen therapy in 1-24 months old patients with bronchiolitis. E Administer an isotonic solution (0.9% NaCl/5% dextrose) and monitor serum sodium routinely when using IV fluids for hydration in 1-24 months old patients with bronchiolitis. E As per PREDICT 2019 guidelines, initiate supplemental hydration with isotonic fluids, either via a nasogastric or IV route, B in infant patients unable to maintain hydration PO. E As per AAP 2014 guidelines, administer nasogastric or IV fluids in infant patients with bronchiolitis unable to maintain oral hydration. B Nebulized hypertonic saline: As per GFRUP 2023 guidelines, avoid using nebulized hypertonic saline routinely in infant patients with bronchiolitis. D As per CPS 2021 guidelines: Insufficient evidence to support the use of hypertonic 3% saline in an ambulatory setting. I Consider administering hypertonic 3% saline in 1-24 months old patients hospitalized > 3 days. E As per PREDICT 2019 guidelines, do not use nebulized hypertonic saline in infant patients presenting to the hospital or hospitalized with bronchiolitis. D As per AAP 2014 guidelines: https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 5/13 6/29/23, 3:21 AM Bronchiolitis Pathway Do not use nebulized hypertonic saline in infant patients with bronchiolitis in the emergency department. D Consider administering nebulized hypertonic saline in hospitalized infant and pediatric patients with bronchiolitis. C Nebulized epinephrine: As per CPS 2021 guidelines: Do not use routine epinephrine in 1-24 months old patients with bronchiolitis. D Continue ongoing epinephrine in 1-24 months old patients with bronchiolitis if a trial of epinephrine inhalation was attempted in the emergency department and there are clear signs of clinical improvement. E As per PREDICT 2019 guidelines, do not use epinephrine in infant patients presenting to the hospital or hospitalized with bronchiolitis. D As per AAP 2014 guidelines, do not use epinephrine in infant and pediatric with bronchiolitis. D Bronchodilators: As per GFRUP 2023 guidelines, avoid using inhaled -2 agonists and/or inhaled epinephrine routinely in infant patients with bornchiolitis. Consider obtaining a therapeutic test to avoid intubation in selected cases. D Show 2 more As per CPS 2021 guidelines, do not use routine salbutamol in 1-24 months old patients with bronchiolitis. D As per PREDICT 2019 guidelines, do not use -2 agonists in 12 months old patients presenting to the hospital or hospitalized with bronchiolitis, D including those with a personal or family history of atopy D As per RACP 2017 guidelines, do not use salbutamol routinely for the treatment of pediatric patients with bronchiolitis. D As per AAP 2014 guidelines, do not use albuterol or salbutamol in infant and pediatric patients with bronchiolitis. D As per SHP 2013 guidelines, do not use bronchodilators routinely in pediatric patients with bronchiolitis. D Corticosteroids: As per GFRUP 2023 guidelines, avoid using corticosteroids, whether inhaled or systemic, in infant patients with brinchiolitis. D As per CPS 2021 guidelines, do not use routine corticosteroids in 1-24 months old patients with bronchiolitis. D As per PREDICT 2019 guidelines, do not use systemic or local corticosteroids in infant patients presenting to the hospital or hospitalized with bronchiolitis. D As per RACP 2017 guidelines, do not use systemic corticosteroids routinely for the treatment of pediatric patients with bronchiolitis. D https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 6/13 6/29/23, 3:21 AM Bronchiolitis Pathway As per AAP 2014 guidelines, do not use systemic corticosteroids in infant patients with bronchiolitis in any setting. D As per SHP 2013 guidelines, do not use systemic corticosteroids in < 2 years old patients with an uncomplicated lower respiratory tract infection. D Antibiotics: As per GFRUP 2023 guidelines, avoid using antibiotics routinely in infant patients with bronchiolitis. Reserve antibiotics for suspected pulmonary superinfection or bacterial co- infection. D As per CPS 2021 guidelines, do not use antibiotics in 1-24 months old patients with bronchiolitis unless there is suspicion of an underlying bacterial infection. D As per PREDICT 2019 guidelines, do not use antibiotics for the treatment of infant patients with bronchiolitis. D Do not use azithromycin in hospitalized infant patients with bronchiolitis, D including those at risk of developing bronchiectasis. D As per AAP 2018 guidelines, do not use antibiotics in pediatric patients with viral respiratory illnesses including bronchiolitis. D As per AAP 2014 guidelines, do not use antibiotics in infant and pediatric patients with bronchiolitis unless there is a strongly suspected or confirmed concomitant bacterial infection. D Therapies with no evidence for benefit: Avoid using helium, ribavirin, deoxyribonuclease, anti-leukotrienes, magnesium sulfate, and inhaled nitric oxide in infant patients with bronchiolitis. D Avoid using caffeine routinely in infant patients presenting with apnea. D 6. Nonpharmacologic interventions Chest physiotherapy: As per GFRUP 2023 guidelines, avoid offering routine respiratory physiotherapy in infant patients with bronchiolitis. D As per CPS 2021 guidelines, do not offer chest physiotherapy in 1-24 months old patients with bronchiolitis. D As per AAP 2020 guidelines, do not offer airway clearance therapy routinely in pediatric patients with bronchiolitis. D As per PREDICT 2019 guidelines, do not offer chest physiotherapy routinely in infant patients with bronchiolitis. D As per AAP 2014 guidelines, do not offer chest physiotherapy in infant and pediatric patients with bronchiolitis. D Nasal suctioning: https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 7/13 6/29/23, 3:21 AM Bronchiolitis Pathway Do not perform nasal suctioning routinely in infant patients with bronchiolitis. Consider performing superficial nasal suctioning to assist feeding in patients with moderate disease. D Do not perform deep nasal suctioning for the management of bronchiolitis. D Do not use nasal saline drops routinely in patients with bronchiolitis. Consider administering a trial of intermittent saline drops at time of feeding. D 7. Patient education General counseling: ask about the exposure of the infant or child to tobacco smoke when assessing infants and children for bronchiolitis. B Counsel caregivers about exposing the infant or child to environmental tobacco smoke and smoking cessation when assessing infants and children for bronchiolitis. B Show 2 more 8. Preventative measures Palivizumab prophylaxis, prematurity: As per NACI 2022 guidelines, offer palivizumab prophylaxis in infants born at < 30 weeks 0 days gestation and aged < 6 months at the onset of or during the RSV season. B Show 3 more As per AAP 2014 guidelines, offer palivizumab prophylaxis in the first year of life in infants born before 29 weeks 0 days of gestation. E Show 2 more Palivizumab prophylaxis (multiple birth): do not offer palivizumab prophylaxis in infants or siblings of multiple births not otherwise qualifying for prophylaxis. D Palivizumab prophylaxis, congenital heart disease: As per NACI 2022 guidelines, offer palivizumab prophylaxis in infants with hemodynamically significant congenital heart disease (as assessed by a pediatric cardiologist) aged > 1 year at the onset of the RSV season. A Show 3 more As per AAP 2014 guidelines, consider offering palivizumab prophylaxis in the first year of life in certain infants with hemodynamically significant heart disease. E Palivizumab prophylaxis, immunodeficiency: As per NACI 2022 guidelines, consider offering palivizumab prophylaxis in < 24 months old patients with severe immunocompromise. B As per AAP 2014 guidelines, consider offering palivizumab prophylaxis in < 24 months old patients expected to be profoundly immunocompromised during the RSV season. E Palivizumab prophylaxis, cystic fibrosis: As per NACI 2022 guidelines: https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 8/13 6/29/23, 3:21 AM Bronchiolitis Pathway Do not offer palivizumab prophylaxis routinely in < 24 months old patients with cystic fibrosis. D Consider offering palivizumab prophylaxis in < 24 months old patients with cystic fibrosis with severe chronic lung disease (defined as requiring ongoing supplemental oxygen in the 6 months before the onset of or during the RSV season). B As per AAP 2014 guidelines, insufficient evidence to support the use of palivizumab prophylaxis in pediatric patients with cystic fibrosis. I Palivizumab prophylaxis, Down syndrome: As per NACI 2022 guidelines, do not offer palivizumab prophylaxis routinely in < 24 months old patients with Down's syndrome. D Offer palivizumab prophylaxis in pediatric patients with Down's syndrome qualifying for prophylaxis because of hemodynamically significant congenital heart disease, chronic lung disease, prematurity, or immunodeficiency. D As per AAP 2014 guidelines, insufficient evidence to support the use of palivizumab prophylaxis in pediatric patients with Down syndrome. I Palivizumab prophylaxis, other comorbidities: As per NACI 2022 guidelines, consider offering palivizumab prophylaxis in < 24 months old patients with severe chronic lung disease of other etiology (such as congenital cystic lung disease, chronic ILD, congenital lung malformations, congenital airway abnormalities, or neuromuscular conditions affecting the ability to clear airway secretions) or requiring home respiratory support (such as supplemental oxygen, mechanical ventilation, CPAP, tracheostomy) if requiring ongoing supplemental oxygen or assisted ventilation in the 6 months before the onset of or during the RSV season. B As per AAP 2014 guidelines, consider offering palivizumab prophylaxis in the first year of life in patients with a pulmonary abnormality or neuromuscular disease impairing the ability to clear secretions from the upper airways. E Palivizumab prophylaxis (prevention of wheezing or asthma): do not offer palivizumab prophylaxis for the prevention of recurrent wheezing or asthma in the absence of other indications. D Palivizumab prophylaxis, prevention of healthcare-associated RSV infection: As per NACI 2022 guidelines, do not offer routine palivizumab prophylaxis to control or prevent RSV infections in neonatal intensive care or other hospital units. D Consider offering palivizumab prophylaxis when all other measures to control an RSV outbreak in a neonatal ICU have failed. D As per AAP 2014 guidelines, do not use palivizumab prophylaxis for the prevention of healthcare-associated RSV disease. D Palivizumab prophylaxis (remote communities): Offer palivizumab prophylaxis in infants aged < 6 months born < 36 weeks of gestation and living in remote northern Inuit communities who would require air transport for hospitalization. B Do not offer palivizumab prophylaxis routinely in healthy full-term infants living in remote northern Inuit communities. A Consider offering palivizumab prophylaxis in healthy full-term https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 9/13 6/29/23, 3:21 AM Bronchiolitis Pathway infants aged < 6 months at the onset of or during the RSV season living in remote northern Inuit communities with documented very high RSV hospitalization rates for term infants. B Consider offering palivizumab prophylaxis in infants aged < 6 months born < 36 weeks of gestation and living in other remote communities with documented high rates of hospitalization for RSV who would require air transport for hospitalization. B Palivizumab prophylaxis, regimens: As per NACI 2022 guidelines, administer palivizumab prophylaxis at a dose of 15 mg/kg by IM injection. Administer the first dose at the onset of the current RSV season, as determined by local laboratory data or pediatric hospitalization data. Consider pre-determining the start date based on dates of previous local RSV seasons if local data are not available in a timely fashion. Administer the second dose 21-28 days after the first dose, and at 28-35-day intervals for further doses. B Show 4 more As per AAP 2014 guidelines, consider administering a maximum of 5 monthly doses of palivizumab (15 mg/kg per dose) during the RSV season in infants qualifying for prophylaxis in the first year of life. Recognize that qualifying infants born during the RSV season may require fewer doses. E Show 2 more Hand hygiene: As per PREDICT 2019 guidelines, ensure proper hand hygiene to reduce hospital-acquired infections. B As per AAP 2014 guidelines: Ensure that all people disinfect their hands before and after direct contact with patients, after contact with inanimate objects in the direct vicinity of the patient, and after removing gloves. B Ensure that all people use alcohol-based rubs for hand decontamination when caring for children with bronchiolitis. Ensure that individuals wash their hands with soap and water if alcohol-based rubs are not available. B 9. Follow-up and surveillance Discharge from hospital: As per PREDICT 2019 guidelines: Take into account oxygen saturations, adequacy of feeding, age (< 8 weeks), and lack of social support at the time of discharge as a risk for representation. E Consider discharging infant patients at low risk for severe bronchiolitis, after a period of observation, on home oxygen with a clear return-to-hospital advice. C As per TSANZ 2018 guidelines, do not delay discharge from an inpatient admission based on oxygen saturations alone if saturations are 90% in pediatric patients with bronchiolitis without other comorbidities. D https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 10/13 6/29/23, 3:21 AM Bronchiolitis Pathway Management of chronic cough: avoid using asthma medications or inhaled osmotic agents in pediatric patients with chronic cough (> 4 weeks) after acute viral bronchiolitis. Clinical findings Patient demographics Symptoms Age < 2 Cough Fever Past medical history Poor feeding Rhinorrhea Acute otitis media UTI Vital signs Ocular exam Tachycardia Tachypnea Conjunctivitis O2 saturation Microbiological findings Respiratory exam RSV RNA Apnea Crackles Grunting Intercostal retractions Nasal flaring Wheezing Imaging findings Atelectasis Patchy pulmonary infiltrates Pulmonary hyperinflation Reticulonodular pulmonary infiltrates Studies 2023 AReSVi-006 In adults 60 years of age, RSVPreF3 OA vaccine was superior to placebo vaccine with respect to RSV-related lower respiratory tract disease. Alberto Papi et al. N Engl J Med. 2023 Feb 16. 2023 PARIS-2 https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 11/13 6/29/23, 3:21 AM Bronchiolitis Pathway In children aged 1-4 years requiring hospital admission for acute hypoxemic respiratory failure, high- flow oxygen therapy was inferior to standard oxygen therapy with respect to median length of hospital stay. 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American Academy of Pediatrics Committee on Infectious Diseases, American Academy of Pediatrics Bronchiolitis Guidelines Committee. Updated guidance for palivizumab prophylaxis among infants and young children at increased risk of hospitalization for respiratory syncytial virus infection. Pediatrics. 2014 Aug;134 2 415 20. Open 6. Jeremy N Friedman, Michael J Rieder, Jennifer M Walton et al. Bronchiolitis: Recommendations for diagnosis, monitoring and management of children one to 24 months of age. CPS. 2021 Nov 30. Open 7. SHP. Choosing Wisely SHP recommendations. SHP. 2013. Open 8. American Academy of Pediatrics. Choosing Wisely AAP recommendations. Choosing Wisely. 2020. Open 9. RACP. Choosing Wisely RACP recommendations. RACP. 2017. Open 10. Anne B Chang, John J Oppenheimer, Bruce K Rubin et al. Chronic Cough Related to Acute Viral Bronchiolitis in Children: CHEST Expert Panel Report. Chest. 2018 Aug;154 2 378 382. Open 11. TSANZ. Choosing Wisely TSANZ recommendations. 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Observer agreement for respiratory signs and oximetry in infants hospitalized with lower respiratory infections. Am Rev Respir Dis. 1992 Jan;145 1 106 9. Open https://web.pathway.md/diseases/recSVEmgKrGNI4oBu 13/13