T.C. Thompson Children’s Hospital Evidence Based Clinical Practice Guidelines for Infants with Bronchiolitis
(September 23, 2010)
Modified from the Cincinnati Children’s Hospital Medical Center Guidelines (August 15, 2005)
Target Population
1. Infants less than one year of age presenting to the hospital for the first time with bronchiolitis typical in presentation and prehospital clinical course.
2. These Guidelines are not intended for use in the following types of bronchiolitis patients:
· Patients with a history of cystic fibrosis, bronchopulmonary dysplasia, asthma, or other significant respiratory disease.
· Patients with immunodeficiencies.
· Patients admitted to an intensive care unit.
· Patients with other significant comorbid conditions complicating care, which may include congenital heart disease, Down syndrome, and conditions which predispose to pulmonary hypertension.
3. For those infants who initially meet guideline criteria but do not subsequently follow a typical course, consideration for a pulmonary consult should be given.
4. The information provided is intended for informational purposes only. This information is derived from clinical experience and clinical research and is intended as a guideline and not as a replacement for any medical provider’s decision making, which shall at all times be and remain in the sole discretion of such provider.
Introduction
Bronchiolitis is an acute inflammatory disorder of the lower respiratory tract, occurring most commonly in infants and young children, caused by infection with seasonal viruses. Respiratory syncytial virus (RSV) accounts for 50% to 80% of cases.1 Other causes include parainfluenza virus, influenza virus, adenovirus, and human metapneumovirus.2 Viral etiology does not reliably predict illness severity.
Typical bronchiolitis is a self-limited disease that is little modified by aggressive evaluations, use of antibiotics, or other therapies. The median duration of illness for children with bronchiolitis is 12 days; after 21 days approximately 18% will remain ill, and after 28 days 9% will remain ill.3 Most infants who contract RSV infection recover without sequelae; however, up to 40% may have subsequent wheezing episodes through five years of age and approximately 10% will have wheezing episodes after age five.4 The average hospital stay is 3-7 days.5-7 RSV associated infant deaths number less than 500 per year in the U.S.; most deaths occur in children without concurrent cardiac or pulmonary disease.8
“Recognizing the pathologic picture that occurs in the airways of children with bronchiolitis is important in understanding the clinical manifestations and developing rational management. The viral infection occurs through the upper respiratory tract and spreads lower within a few days. This results in inflammation of the bronchiolar epithelium, with peribronchial infiltration by mostly mononuclear cells and edema of the submucosa and adventitia. Plugs of sloughed, necrotic epithelium and fibrin in the airways cause partial or total obstruction to airflow. The degree of obstruction may vary as these areas are cleared, resulting in rapidly changing clinical signs that confound an accurate assessment of the severity of illness. A ‘ball-valve’ mechanism can result in trapping of air distal to obstructed areas, with subsequent absorption, atelectasis, and a mismatch of pulmonary ventilation and perfusion that may lead to hypoxemia. Atelectasis may be accelerated by the lack of collateral channels in young children and potentially by the administration of high concentrations of supplemental oxygen, which is absorbed more rapidly than room air. Smooth muscle constriction seems to have little role in the pathologic process, which may explain the limited benefit of bronchodilators observed in clinical studies.” 9 (p 343)
Several studies of the use of clinical guidelines for the management of bronchiolitis have shown a reduction in unnecessary resource utilization with a streamlining of medical care for these infants.5,10-15
This document provides a practical, evidence based approach to the diagnosis and management of acute bronchiolitis in infants and children less than two years of age. The recommendations are based on the most current and best scientific information available. In the absence of quality evidence, expert opinion and group consensus were used.
Guideline Recommendations
Prevention:
1. High Risk Patients: Infants with the following conditions are at increased risk of significant morbidity from bronchiolitis andare at increased risk for hospitalization:
· age < 3 months
· prematurity (<35 weeks corrected gestational age)
· chronic lung disease
· congenital heart disease
· immune deficiencysyndromes8,16-19
Prevention of bronchiolitis in thesepatients is of primary importance. Specific measures to prevent bronchiolitis include:
· limiting exposure to contagious settings (i.e., daycare) and siblings
· eliminating exposure to second-hand tobacco smoke
· careful handwashing to minimize spread of viruses.
These measuresshould bediscussed regularly with parents of newborns uponnursery discharge and atprimary care visits for all high risk patients listed above during bronchiolitis season.
Additionally, preventive medical therapy such as palivizumab (Synagis®, MedImmune) may be considered for selected, high-risk patients. Please refer to the current edition of the AAP's RedBook forrecommendations on palivizumab's indications and dosing.
2. Nosocomial Prevention: Transmission of RSV and other respiratory viruses occurs by direct inoculation of contagious secretions from the hands or by large-particle droplets into theeyes and nose, but rarely the mouth.20,21 Nosocomial infection may place medically fragilepatients at increased risk for morbidity and mortality.22 It is therefore recommended that droplet and contactisolation measures be followed for all patients with bronchiolitis.23
· "Droplet Precautions" and "Contact Precautions" signs are to be placed on the patient's door
· A private room is preferred
· Patients are not allowed in common areas (i.e., playroom) or other patient rooms
· A surgical mask is to be worn by all healthcare workers within 3 feet of the patient
· Protective eyewear is encouraged
· Strict hand washing should precede and follow all patient encounters and gloves should be worn by all who enter room
· Impervious cover gowns should be worn when it is anticipated that clothing will have contact with the patient or patient's environment
· Dedicated patient equipment should remain in the patient's room and not be shared with other patients.
· A disposable stethoscope provides a sub-optimal auscultory exam. A dedicated stethoscope should remain in the patient’s room and be sanitized upon discharge.
General:
The basic management of typical bronchiolitis is anchored in the provision of therapies that ensure the patient is clinically stable, well oxygenated, and well hydrated. The main benefits of hospitalization of infants with bronchiolitis are the careful monitoring of clinical status, maintenance of a patent airway (through positioning, suctioning, and mucus clearance), maintenance of adequate hydration, and parental education24-27 (Local Expert Consensus).
Diagnosis and Assessment:
The diagnosis of bronchiolitis and assessment of its severity is rooted in the clinician’s interpretation of the constellation of characteristic findings and is not dependent on any specific clinical finding or diagnostic test.
“Clinicians recognize bronchiolitis as a constellation of clinical symptoms and signs including a viral upper respiratory prodrome followed by increased respiratory effort and wheezing in children less than 2 years of age.”28 (pp1776-7)
Clinical signs and symptoms of bronchiolitis may include rhinorrhea, cough, auscultatory findings of wheezing or crackles, tachypnea, and increased respiratory effort manifested by grunting, nasal flaring, and intercostal and/or subcostal retractions. The physical exam reflects the variability in the disease state and benefits from serial observations over time to fully assess the child’s status. Upper airway obstruction may contribute to the work of breathing, and nasal suctioning and positioning of the child may affect the assessment.
Other important issues to assess in the patient with bronchiolitis include the impact of respiratory symptoms on feeding and hydration and the response, if any, to therapy. The ability of the family to care for the child and return for further care should also be assessed. A history of underlying conditions such as prematurity, cardiac or pulmonary disease, immunodeficiency, or previous episodes of wheezing should be identified.
Several studies have associated premature birth (less than 37 weeks) and young age (less than 6-12 weeks) with an increased risk of severe disease.6,29,30 Other underlying conditions that have been associated with an increased risk of progression to severe disease or mortality include hemodynamically significant congenital heart disease, chronic lung disease (bronchopulmonary dysplasia, cystic fibrosis, congenital anomaly), and the presence of an immunocompromised state.28
Apnea is a specific and important concern in the management of young infants with bronchiolitis, especially with RSV. In a retrospective study of 691 infants younger then 6 months of age hospitalized for bronchiolitis, apnea occurred in 19 (2.7%).31 Risk factors included either (1) history of an apneic event having already occurred or (2) young age, defined as less than 1 month for term infants or a postconceptional age of less than 48 weeks for premature infants.
Laboratory and Radiographic Tests:
Routine laboratory studies are generally not necessary and may result in increased rates of unnecessary hospital admissions and therapies and unwarranted diagnostic testing.
· Chest X-Rays are not routinely recommended and should only be obtained as clinically indicated when the diagnosis of bronchiolitis is unclear or when the presentation is severe.13,32-34
· Routine testing for the presence of RSV antigen or other viral infections by PCR from nasopharyngeal washings is not recommended for infants >8 weeks of age. Similarly, risk of serious bacterial infection in infants >8 weeks of age with bronchiolitis is extremely low, and so routine cultures of blood and CSF are not recommended.13,14,25,35-40
§ Those infants not following a typical course may, however, warrant a rapid respiratory panel for diagnostic purposes (Local Expert Consensus).
· In the infant <8 weeks of age with clinical symptoms of bronchiolitis and a positive RSV antigen, routine blood and spinal fluid cultures are not indicated.41 There is, however, a clinically relevant rate (approximately 5%) of UTI in these infants, thus urinalysis and urine culture should be considered.36,37,42,43
· Capillary or arterial blood gas testing is recommended only as clinically indicated for individual patients28 (Local Expert Consensus).
Medications:
1. Oxygen therapy is frequently required in the treatment of bronchiolitis. It is recommended that oxygen saturation monitoring be utilized to maintain blood oxygen levels within a normal range. This range is variable in definition and patient specific, though in general adequate arterial oxygen levels are achieved when the oxygen saturation is between 90% and 94%. Therefore, starting supplemental oxygen when the saturation is consistently less than 90% and weaning oxygen when it is consistently higher than 94% is considered reasonable44
· See the Monitoring section for recommendation regarding oxygen saturation monitoring.
2. Hypertonic saline
· In 2008, a Cochrane review stated: “Current evidence suggests nebulized 3% saline may significantly reduce length of stay and improve the clinical severity score in infants with acute viral bronchiolitis.” 45 There are many other studies that suggest hypertonic saline may be of some clinical benefit in bronchiolitis improving clinical scores and length of hospital stay.46-50 However, these studies allowed the use of bronchodilators with the hypertonic saline for fear of inducing bronchospasm as a complication of hypertonic saline as single therapy. One study has recently shown that the overall adverse event rate for single therapy hypertonic saline is relatively low at 1%.51
· Hypertonic 3% saline may be used to promote airway clearance. Evidence suggests that adverse events are uncommon, but may result in deterioration of clinical status and bronchiolitis clinical score. If that occurs consideration should be given to stopping this treatment.46,47,51,52
3. Bronchodilators:
· Although widely used and studied, the efficacy of inhaled bronchodilators in the treatment of bronchiolitis is uncertain, and the published results have been variable. For this reason, multiple evidence-based systemic reviews and meta-analysis studies have been done regarding their use. Based on the evidence reviewed by this committee, bronchodilators should not routinely be used among inpatients as there has been no proven benefit in length of hospital stay or long term clinical outcome.9,28,53-55
· Deterioration has been associated with bronchodilator inhalation therapies.56,57 Therefore, if a trial of bronchodilator inhalation therapy is undertaken, and there is no significant improvement in clinical appearance between 15-30 minutes,24,58 it is recommended that the therapy not be continued or repeated (Local Expert Consensus).
· Inhaled Beta Agonists:
§ From a recent Cochrane review: “Bronchodilators [other than epinephrine] produce small short-term improvements in clinical scores among infants with bronchiolitis and may slightly improve oxygenation in those treated as outpatients. However, given the high costs, incidence of adverse effects and uncertain efficacy based on the findings of this meta-analysis, bronchodilators cannot be recommended for routine management of first time wheezers who present with the clinical findings of bronchiolitis. Bronchodilators should not be used in patients who are hospitalized with bronchiolitis.” 53 (p8)
§ Other studies support that it is reasonable to give a trial of nebulized albuterol therapy with close monitoring for clinical improvement to patients with significant risk factors for asthma. These include a prior history of wheezing or eczema, or a first-degree relative with asthma. Scheduled or serial use of bronchodilator aerosol therapies is not recommended unless there is documented objective clinical improvement.9,28,54,59,60
§ Three meta-analysis and several randomized controlled trials have not shown dramatic effects on clinical scores or hospitalization rates from therapy with nebulized albuterol.53,61-63
§ In the majority of cases the use of inhalation therapies and other treatments effective for treating the bronchospasm characteristic in asthma will not be efficacious for treating the airway edema typical of bronchiolitis.20,24
· Inhaled Epinephrine:
§ In 2004, a Cochrane review stated: “There is insufficient evidence to support the use of epinephrine for the treatment of bronchiolitis among inpatients. There is some evidence to suggest that epinephrine may be favorable to salbutamol and placebo among outpatients.”55 (p2)
· Among the 5 inpatient studies comparing nebulized epinephrine to placebo, only one showed a statistically significant outcome that favored epinephrine. That outcome was an improvement in clinical score at 60 minutes. Among the 4 inpatient studies comparing epinephrine and salbutamol, only one had statistically significant clinical improvement favoring epinephrine. That improvement was a better respiratory rate at 30 minutes. In all studies reviewed, there were no long term clinical improvements favoring epinephrine.55