Bronchiolitis


Bronchiolitis is an epidemic and seasonal viral infection of the lower respiratory tract in children less than 2 years of age, characterised by bronchiolar obstruction.
Respiratory syncytial virus (RSV) is responsible for 70% of cases of bronchiolitis. Transmission of RSV is direct, through inhalation of droplets (coughing, sneezing), and indirect, through contact with hands or materials contaminated by infected secretions.
In the majority of cases, bronchiolitis is benign, resolves spontaneously (relapses are possible), and can be treated on an outpatient basis.
Severe cases may occur, which put the child at risk due to exhaustion or secondary bacterial infection. Hospitalisation is necessary when signs/criteria of severity are present (10 to 20% of cases).

Clinical features

– Tachypnoea, dyspnoea, wheezing, cough; profuse, frothy, obstructive secretions.
– On auscultation: prolonged expiration with diffuse, bilateral wheezes; sometimes diffuse fine, end-inspiratory crackles.
Rhinopharyngitis, with dry cough, precedes these features by 24 to 72 hours; fever is absent or moderate.

– Signs of severity:
• Significant deterioration in general condition, toxic appearance (pallor, greyish colouration)
• Apnoea, cyanosis (check lips, buccal mucosa, fingernails)
• Respiratory distress (nasal flaring, sternal and chest wall indrawing)
• Anxiety and agitation (hypoxia), altered level of consciousness
• Respiratory rate > 60/minute
• Decreased respiratory distress and slow respirations (< 30/minute below the age of 1 year and < 20/minute below the age of 3 years, exhaustion). Exercise caution in interpreting these signs as indicators of clinical improvement.
• Sweats, tachycardia at rest and in the absence of fever
• Silence on auscultation (severe bronchospasm)
• Difficulty drinking or sucking (reduced tolerance for exertion)

Treatment

Treatment is symptomatic. Obstructive signs and symptoms last for about 10 days; cough may persist for 2 weeks longer.

Hospitalise children with one of the following criteria:
– Presence of any sign of severity
– Pre-existing pathology (cardiac or pulmonary disease, malnutrition, HIV, etc.)

Consider hospitalisation on a case-by-case basis in the following situations:
– Associated acute pathology (viral gastro-enteritis, bacterial infection, etc.)
– Age less than 3 months

In all other cases, the child may be treated at home, provided the parents are taught how to carry out treatment, and what signs of severity should lead to re-consultation.

Outpatient treatment

– Nasal irrigation with 0.9% NaCl before each feeding (demonstrate the technique to the mother)1 .
– Small, frequent feedings to reduce vomiting triggered by bouts of coughing.
– Increased fluids if fever and/or significant secretions are present.
– Treat fever (Chapter 1).
– Handle the patient the patient as little as possible and avoid unnecessary procedures.

Hospitalisation

– In all cases:
• Place the infant in a semi-reclining position (± 30°).
• Nasal irrigation, small, frequent feeds, treatment of fever: as for outpatient treatment.
• Gentle oro-pharyngeal suction if needed.
• Monitor fluid intake: normal requirements are 80 to 100 ml/kg/day + 20 to 25 ml/kg/day with high fever or very profuse secretions.

– According to symptoms:
• Humidified nasal oxygen (1 to 2 litres/minute).
• When there is vomiting or significant fatigue when sucking, fluid requirements may be administered by nasogastric tube (small volumes on a frequent basis) or the IV route, for the shortest possible time. Avoid breastfeeding or oral feeds in children with severe tachypnoea, but do not prolong NG feeds (respiratory compromise) or IV infusions any longer than necessary.
• Bronchodilator therapy: this therapy may be considered after a trial treatment has been given (salbutamol inhaler, 100 micrograms/puff: 2 to 3 puffs with spacer, repeated twice at an interval of 30 minutes). If inhaled salbutamol appears effective in relieving symptoms, the treatment is continued (2 to 3 puffs every 6 hours in the acute phase, then gradual reduction as recovery takes place). If the trial is ineffective, the treatment is discontinued.
• Antibiotics are not indicated unless there is concern about complications such as secondary bacterial pneumonia.

Prevention and control

The risk of transmission of the virus is increased in hospital settings:
– Children with bronchiolitis should be grouped together, away from other children (cohorting).
– As infection is most commonly transmitted by the hands, the most important prevention measure is hand-washing after any contact with patients, and objects or surfaces in contact with patients on which the virus may survive for several hours.
– In addition, staff should wear gowns, gloves and surgical masks when in contact with patients.



Footnotes
Ref Notes
1 Lie the child on his back, head turned to the side and instil 0.9% NaCl into the nose, one nostril at a time.