UPDATES IN BRONCHIOLITI

SHUMAID AL HINAI

Overview

Definition

Clinical features

Management

COmplications

DEFINITION defined as follows:

is the first episode of wheezing in a child younger than 12 to 24 months who has physical findings of a viral respiratory infection and has no other explanation for the wheezing, such as pneumonia or atopy.

The definition for most clinical studies

CAUSEs

The number of viruses expanded.

RSV account for 50% to 80% of cases.

11 Other causes include the parainfluenza viruses ( type 3 ) , influenza, and human metapneumovirus (HMPV).

HMPV account for 3% to 19% of cases.

clinical courses of RSV and HMPV similar

most children are infected during annual widespread wintertime Epidemics.

Human metapneumovirus (HMPV)

infected with more than 1 virus.

Rates of coinfection 10% - 30% , most commonly with RSV and either HMPV or rhinovirus.

A recent large prospective study of children younger than 5 years of age hospitalized with RSV infection revealed a coinfection rate of 6%.

Bronchiolitis: Recent Evidence on Diagnosis and ManagementJoseph J. Zorc and Caroline Breese Hall

Pediatrics 2010;125;342-349; originally published online Jan 25, 2010;DOI: 10.1542/peds.2009-2092

Risk factors   Risk factors for severe RSV disease and/or complications include:

Prematurity (gestational age <37 weeks) Low birth weight Age less than 6 to 12 weeks Chronic pulmonary disease (bronchopulmonary dysplasia, cystic

fibrosis, congenital anomaly) Hemodynamically significant congenital heart disease (eg, moderate

to severe pulmonary hypertension, cyanotic heart disease, or congenital heart disease that requires medication to control heart failure)

Immunodeficiency Neurologic disease Congenital or anatomical defects of the airways

CLINICAL FEATURES  

a viral upper respiratory prodrome followed by increased respiratory effort and wheezing

Infants with moderate to severe, typically present for medical attention 3-6 days after illness onset.

Often preceded by 1-3 days h/o URT symptoms, such as nasal congestion and/or discharge and mild cough.

It typically presents with: - fever (usually ≤38.3ºC) - cough - mild respiratory distress.

Compared to other viruses, fever tends to be lower with RSV and higher with adenovirus.

 

aspects that help in determining the severity of illness and need for hospitalization include :

Assessment of hydration status Symptoms of respiratory distress (tachypnea, nasal

flaring, retractions, grunting) Cyanosis, indicating profound hypoxemia Episodes of restlessness or lethargy (may indicate

hypoxemia and/or impending respiratory failure)

Physical examination tachypnea and intercostal and subcostal retractions, often with

expiratory wheezing.

The chest: hyperexpanded & ? hyperresonant to percussion.

expiratory wheeze, prolonged expiratory phase, and both coarse and fine crackles.

Mild hypoxemia commonly is detected.

Wheezing may not be audible if the airways are profoundly narrowed.

Other examination findings may include - mild conjunctivitis - pharyngitis - otitis media.

AAP defines severe disease as: "signs and symptoms associated with poor

feeding and respiratory distress characterized by tachypnea, nasal flaring, and hypoxemia".

)AAP : (American Academy of Pediatrics

Factors that have been associated with increased illness severity include:

Toxic or ill appearance Oxygen saturation <95 % while breathing room air Age younger than 3 months Respiratory rate ≥70 breaths per minute ** Atelectasis on chest radiograph

Evaluation

Laboratory tests and radiographs are not routinely indicated.

CBC and chest radiograph are indicated in patients with an unusual clinical course or severe disease

Radiographs

Chest radiographs are not necessary in the routine evaluation of bronchiolitis.

unlikely to alter treatment and may lead to inappropriate use of antibiotics.

Indications of Radiographs

In infants and young children with moderate or severe respiratory distress

if there are focal findings on examination - cardiac murmur

to exclude alternate diagnoses in children who fail to improve at the expected rate.

Studies evaluating whether radiographic findings are predictive of disease severity have had conflicting results.

One study randomly assigned 522 infants (2 to 59 months) with acute LRTI to receive or not receive a chest radiograph.

Children in the radiograph group were more likely to be diagnosed with pneumonia or upper respiratory infection, whereas children in the no-radiograph group were more likely to be diagnosed with bronchiolitis.

In addition, more likely to be treated with antibiotics. The median time to recovery was seven days in both groups.

Swingler, GH, Hussey, GD, Zwarenstein, M. Randomised controlled trial of clinical outcome after chest radiograph in

ambulatory acute lower-respiratory infection in children. Lancet 1998; 351:404.

Diagnosis

It is diagnosed clinically.

The diagnosis may be supported by radiographic or laboratory studies, but these tests are not necessary for diagnosis

There is debate about whether testing for specific viral agents alters Mx or outcome

The AAP ------- rarely alter management decisions or outcomes for the majority

However, the identification of a viral etiologic agent has been associated with a decreased utilization of antibiotic treatment

DD

Bronchiolitis must be distinguished from a variety of acute and chronic conditions.

These include: - viral-triggered asthma or wheezing - pneumonia - chronic lung disease - foreign body aspiration - gastroesophageal reflux disease - and/or dysphagia leading to aspiration - congenital heart disease - heart failure - vascular rings.

Treatment

self-limited disease.

Factors that should be considered in Mx decisions include:

- the age of the child

- the stage of infection at the time supportive care was begun

- the disease severity

- premorbid diagnoses

- the cause and site of airway obstruction

Indications for hospitalization  

In general, criteria for hospitalization include:

Toxic appearance, poor feeding, lethargy, and dehydration

Moderate to severe respiratory distress, manifested by : - nasal flaring - intercostal retraction - respiratory rate >70 ** - and/or cyanosis. Apnea

Hypoxemia (O2 sat <95% RA) with or without hypercapnia (PCO2: >45 mmHg).

The parents are unable to care for the child at home

Respiratory support   Oxygen to maintain the sat above 90 to 92%.

Data are lacking to support the use of a specific cutoff value.

The AAP practice guideline recommends oxygen sat <90 % as the threshold to start supplemental oxygen.

However, variability in the accuracy of oximeters, and the presence of fever, acidosis, and hemoglobinopathy favor the use of a higher cutoff value.

In addition, there is evidence suggest that chronic or intermittent hypoxia (oxygen saturation 90 to 94 %) may have long-term cognitive and behavioral effects.

Close monitoring is required as supplemental oxygen is weaned

Infants with PCO2 >55 mmHg, hypoxemia despite oxygen supplementation, and/or apnea may require mechanical ventilation

Fluid administration 

Parenteral fluid administration may be necessary to ensure adequate hydration and avoid the risk of aspiration.

BUT, not in all ***

Fluid and electrolyte status should be carefully monitored.

Chest physiotherapy 

should not be used.

The use of chest physiotherapy is discouraged because it may increase the distress and irritability of ill infants.

A systematic review of three randomized trials concluded that chest physiotherapy using vibration and percussion did not improve clinical score, reduce supplemental oxygen requirement, or reduce length of hospital stay.

PHARMACOLOGIC THERAPY

Bronchodilators

Although, ? Eficacy

difficult to sort out responders/not.

The clinical practice guideline of AAP recommends that bronchodilators should not be used routinely in the management of bronchiolitis.

• a carefully monitored trial of bronchodilator medication is an option, with continuation only if there is a documented objective clinical response.

• Various scoring systems to document clinical response have been used;

• one is available through the University of Cincinnati (www.cincinnatichildrens.org/svc/alpha/h/health-policy/ev-based/bronchiolitis.htm

trial of inhaled bronchodilators.

Each patient should be assessed before and up to one hour after treatment.

Salbutamol is first choice

Dose:  0.15 mg/kg (minimum 2.5 mg; maximum 5 mg) diluted in 2.5 to 3 mL saline and administered over 5 to 15 minutes; or 4 to 6 puffs via a MDI with spacer and facemask.

If no benefit is observed in one hour, administer a single dose of nebulized epinephrine:

Epinephrine  - Dose: 0.5 ml/kg ,, Max 5 ml - Racmic (0.05 mL/kg of 2.25 % epinephrine diluted in 3

mL normal saline). No response within one hour of epinephrine treatment,

do not continue the use of these agents.

If there is a response to either one , can be every 4-6 hrs and discontinued when the S&S of respiratory distress improve.

FIGURE 1 Cochrane collaboration systematic review of studies that assessed the difference in rate of improvement after 2-agonist bronchodilators or

placebo among children with bronchiolitis. (Reproduced with permission from Gadomski AM, Bhasale AL. Cochrane Database Syst Rev. 2006;

(3):CD001266.)

A 2006 Cochrane systematic review of studies that compared bronchodilators for the management of bronchiolitis in outpatients suggested a potential benefit with epinephrine administration.

However, several more recent studies did not support the routine use of epinephrine.

Oral bronchodilators  not recommended.

The efficacy of oral salbutamol was evaluated in a randomized trial of 129 infants with bronchiolitis who were discharged to home from the emergency department.

1 wk salbutamol or placebo.

The median time to resolution of illness was similar in the two groups.

Patel, H, Gouin, S, Platt, RW. Randomized, double-blind, placebo-controlled trial of oral albuterol

in infants with mild-to-moderate acute viral bronchiolitis. J Pediatr 2003; 142:509.

Glucocorticoids

should not be used routinely.

may be beneficial for patients with: - chronic lung disease (BBD) - those with previous episodes of wheezing (ie, who may be at risk for asthma).

Such patients may benefit from a short course of prednisolone:

Prednisolone  (1 to 2 mg/kg per day in one dose or divided into two doses per day for three to seven days).

Alternative dexamethasone (0.4 mg/kg per day in one dose for 3 to 5 days).

Additional data are required before systemic glucocorticoid therapy can be recommended in patients with less severe disease not requiring hospitalization

Inhaled glucocorticoids 

have not been shown to be beneficial.

A randomized trial of nebulized budesonide versus placebo in 161 infants hospitalized with respiratory syncytial virus (RSV) bronchiolitis

found no significant differences in symptom duration, readmission rates, or other endpoints between the two treatment groups.

Cade, A, Brownlee, KG, Conway, SP, et al. Randomised placebo controlled trial of nebulised corticosteroids

in acute respiratory syncytial viral bronchiolitis. Arch Dis Child 2000; 82:126.

Treatment Bronchodilators plus glucocorticoids

A large, multicenter trial evaluated the effectiveness of combination therapy in preventing hospitalization in 800 infants presenting to ED with bronchiolitis

The infants were randomly assigned to one of four treatment groups: - nebulized epinephrine and oral placebo;

- oral dexamethasone and inhaled placebo;

- nebulized epinephrine and oral dexamethasone;

- nebulized and oral placebo. 

N Engl J Med. 2009 May 14;360(20):2079-89.Epinephrine and dexamethasone in children with bronchiolitis.

Pediatric Emergency Research Canada (PERC)

Treatment

Outcomes in the dexamethasone and epinephrine monotherapy groups did not differ significantly from those in the placebo group.

Com. was associated with a decreased rate of hospitalization one week after enrollment (17 versus 24 to 26 percent in the other groups), but the result was not significant when adjusted for multiple comparisons (relative risk, 0.65, adjusted 95% CI 0.41-1.03).

N Engl J Med. 2009 May 14;360(20):2079-89.Epinephrine and dexamethasone in children with bronchiolitis.

Pediatric Emergency Research Canada (PERC)

Ribavirin

is not recommended routinely.

may still play a role in immunocompromised patients and those with severe bronchiolitis due to RSV.

remains controversial.

Consideration of use should be done early in the illness and on a case-by-case basis.  

• Antibiotics • only when there is evidence of a coexisting

bacterial infection (eg, positive urine culture, acute otitis media, consolidation on chest radiograph)

• Such infections should be treated in same manner as in absence of bronchiolitis.

 

Heliox is a mixture of helium (70 - 80 %) and oxygen (20 -

30 %).

flow through airways with less turbulence and resistance than supplemental oxygen (nitrogen/oxygen), thus improving ventilation and decreasing the work of breathing

  has been evaluated in several small randomized trials

with mixed results

Nonstandard therapies

Anti-RSV preparations

use of IV immunoglobulin with a high neutralizing activity against RSV (RSV-IGIV, which has been discontinued) or RSV-specific humanized monoclonal antibody (palivizumab) has failed to improve outcomes in infants with or without risk factors, hospitalized with RSV infection

Surfactant 

Clinical and laboratory evidence suggests that severe bronchiolitis may result in secondary surfactant deficiency.

Several small randomized trials have evaluated the effects of surfactant therapy in mechanically ventilated infants with bronchiolitis.

A meta-analysis of these trials concluded that surfactant therapy may shorten the duration of mechanical ventilation and duration of ICU stay in children with bronchiolitis.

However, additional data are needed before reliable estimates of the magnitude of the effects can be made.

Hypertonic saline 

theoretically has the potential to reduce airway edema and mucus plugging

Several trials have indicated a potential benefit of 3 % saline compared to normal (0.9 %) saline.

In a meta-analysis of three trials (189 patients), treatment of children hospitalized with acute bronchiolitis with nebulized 3% saline

 was associated with decreased mean length of stay (mean difference -0.94 days (95% CI -1.48-(-0.4) days).

No adverse events related to nebulized 3% saline were reported.

CONCLUSIONS: Current evidence suggests nebulized 3% saline may significantly reduce the length of hospital stay and improve the clinical severity score in infants with acute viral bronchiolitis.

Montelukast

Its role in Rx, was evaluated in a randomized trial in 53 infants and young children (>4 weeks to ≤2 years; mean age 3.8 months).

Treatment with montelukast did not affect the clinical course, oxygen saturation, length of stay, or cytokine levels.

Additional studies are necessary to determine what role, if any.

CONCLUSIONS: Montelukast did not improve the clinical course in acute bronchiolitis. No significant effect of montelukast on the T-helper 2/T-helper 1 cytokine ratio when given in the early acute phase could be demonstrated.

Bronchiolitis: Recent Evidence on Diagnosis and ManagementJoseph J. Zorc and Caroline Breese Hall

Pediatrics 2010;125;342-349; originally published online Jan 25, 2010;DOI: 10.1542/peds.2009-2092

DISCHARGE CRITERIA

No established criteria for discharge. One clinical practice guideline suggests the following:

RR <70 breaths/min Caretaker can clear the infant's airway using bulb suctioning Patient is stable without supplemental oxygen Patient has adequate oral intake to prevent dehydration The resources at home are adequate to support the use of any necessary

home therapies (eg, inhalation therapy if the trial was successful and this therapy is to be continued)

Caretaker is confident they can provide care at home Education of the family is complete

Mx Guidline

Complications

The most frequent complications are:

acute respiratory abnormalities, of which apnea and respiratory failure are the most serious

Secondary bacterial infection 

Apnea may occur in infants, particularly in those born prematurely and those younger than two months of age (eg, those with postmenstrual age <48 weeks).

In a retrospective review, 21 percent of 185 infants younger than 12 months who were hospitalized with RSV infection presented with apnea.

Presenting with apnea is a risk factor for respiratory failure and the need for mechanical ventilation.

Take Home Ms

1. Crackles should be reassessed after Neb.

2. Saturation not during sleep.

3. Gases are not routinely done BUT in sever cases.

4. Hydration is based on assessment

5. The dose of Salbutamol & Epinephrine Neb.

6. X ray

7. Severity Score.

REFRENCES

Bronchiolitis: Recent Evidence on Diagnosis and Management. Joseph J. Zorc and Caroline Breese Hall. Pediatrics 2010;125;342-349; originally published online Jan 25, 2010;DOI: 10.1542/peds.2009-2092

Uptodate, Bronchiolitis in infants and children: Treatment; outcome; and prevention, Last literature review for version 17.3: September 30, 2009

Uptodate, Bronchiolitis in infants and children: Clinical features and diagnosis Last literature review for version 17.3: September 30, 2009