History

Fact Explanation
Fever Due to initial upper respiratory tract infection followed by lower respiratory tract infection, caused by the Respiratory Syncytial virus (RSV), Parainfluenza, Mycoplasma and other viruses [1] .
Rhinorrhoea Initial upper respiratory tract infection causing increased secretions.
Cough Stimulation of cough receptors in the respiratory tract epithelium, by secretions caused by inflammation of the bronchioles [2].
Poor feeding Due to dyspnoea [3].
Apnoea Reduced stimulation of the respiratory center by lack of carbon dioxide, caused by compensatory hyperventilation to overcome the hypoxia [4].
References
  1. KLEIGMAN, Robert M, Richard E. BEHRMAN, Hal B. JENSON, Bonita F. STANTON. Nelson textbook of paediatrics. 18th ed. Philadelphia,PA: Elsevier, 2007.
  2. KUMAR, Praveen, Michael CLARK. Kumar & Clark's clinical medicine. 7th ed. Spain: Elsevier, 2009.
  3. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf
  4. GANONG, William F. Review of medical physiology. 22nd ed. Singapore: McGraw-Hill, 2005.

Examination

Fact Explanation
Tachypnoea Increased effort of breathing.
Expiratory wheeze Oscillation of narrowed bronchioles of which the radius is narrowed by edema, mucus, cellular debris and bronchospasm caused by inflammation and further narrowed during expiration [1].
Nasal flaring Increased effort of breathing.
Subcostal, intercostal and supraclavicular recessions Increased effort of breathing [2].
Hyper-inflated chest with prominent sternum and liver displaced downwards Trapping of air during expiration as the resistance to flow is more due to further reduction of the radius of the bronchiole, resulting in hyper inflation [1].
Fine inspiratory crackels Noice produced by the abrupt opening of the peripheral airways during inspiration, which were collapsed during expiration [3].
Prolonged expiration Activates Hearing-Breuer reflex and allow secretions to flow from small airways to larger airways up to the trachea [4].
Cyanosis Hypoxia due to ventlation-perfusion mismatch [1].
References
  1. KLEIGMAN, Robert M, Richard E. BEHRMAN, Hal B. JENSON, Bonita F. STANTON. Nelson textbook of paediatrics. 18th ed. Philadelphia,PA: Elsevier, 2007.
  2. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf
  3. KUMAR, Praveen, Michael CLARK. Kumar & Clark's clinical medicine. 7th ed. Spain: Elsevier, 2009.
  4. KHUMAN, P. Ratan, Lourembam SURBALA, Priyanka MEHTA, Ankita MAKWANA. Infant with bronchiolitis and chest physical therapy: A case report. Scholars Journal of Medical Case Reports [online]. Scholars Academic and Scientific Publishers. 2014, 2(1):3-6 [viewed 02 March 2014]. Available from: http://saspjournals.com/sjmcr

Differential Diagnoses

Fact Explanation
Bronchial asthma Will cause wheezing with or without a preceding history of respiratory tract infection. Suspect if there is family history of asthma or personal history of atopy such as allergic conjunctivitis, eczema or food allergy [1].
Foreign body aspiration Suspect if wheezing is of acute onset and there is associated choking. May have features of complications such as lung consolidation in pneumonia, hemoptysis, obstructive emphysema followed by atelectasis [1].
Pneumonia The child will be severely ill with marked respiratory distress and high fever, if the pneumonia is bacterial in origin [1]. Note: an important examination finding would be features of lung consolidation [1].
Congestive cardiac failure Will cause respiratory distress and cyanosis. Suspect if the child has failure to thrive, scalp sweating and fatigue with breast feeding, basal crepitations and hepatomegaly. Wheezing is caused by pulmonary edema in left heart failure, by obstruction of the bronchioles by engorged lymphatics and blood vessels [1] .
Gastro-esophageal reflux disease Causes wheezing associated with gagging, choking and aversion to food leading to failure to thrive. Wheezing is most commonly seen after meals [1].
Congenital malformations of the respiratory tract Laryngomalacia, tracheomalacia, vascular ring, tracheo-esophageal fistula and aberrant tracheal bronchus are some causes of wheezing in infancy [1],
Interstitial lung diseases Will cause wheezing and respiratory distress. The clinical features are continuous and not episodic as in infectious disease [1].
References
  1. KLEIGMAN, Robert M, Richard E. BEHRMAN, Hal B. JENSON, Bonita F. STANTON. Nelson textbook of paediatrics. 18th ed. Philadelphia,PA: Elsevier, 2007.

Investigations - for Diagnosis

Fact Explanation
Chest radiograph Reveals hyper-inflated lungs with patchy atelectasis [1]. Note: Acute bronchiolitis is essentially a clinical diagnosis. Investigations to diagnose should not be carried out in typical acute bronchiolitis, except when there is diagnostic uncertainty [2].
Viral testing by rapid immunofluorescence, polymerase chain reaction or culture Can be used when the diagnosis is uncertain or for epidemiological studies [1]. Note: Rapid testing for Respiratory Syncytial virus is recommended for hospitalized infants to guide cohort arrangements [2].
References
  1. KLEIGMAN, Robert M, Richard E. BEHRMAN, Hal B. JENSON, Bonita F. STANTON. Nelson textbook of paediatrics. 18th ed. Philadelphia,PA: Elsevier, 2007.
  2. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf

Investigations - Fitness for Management

Fact Explanation
Pulse oxymetry A useful guide to asses the severity of the diseases and decide on management [1].
Arterial/capillary blood gases Help in the assessment of infants with severe respiratory distress and those who are entering respiratory failure. Arterial carbon dioxide values may be useful in deciding on the need of high dependency or intensive care [1].
References
  1. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf

Management - General Measures

Fact Explanation
Oxygen therapy To treat hypoxia. Supplemental oxygen should be given to infants with oxygen saturation <90%. Oxygen may be discontinued of the saturation is at or above 90% and the infant is feeding well and has minimal respiratory distress [1].
Maintain fluid balance To maintain good input which can be difficult due to poor feeding associated with dyspnoea. Consider naso-gastric feeding in infants who cannot maintain oral intake [1]. Important: Caution should be taken in fluid balance as there is a risk of Syndrome of Inappropriate ADH Secretion associated with bronchiolitis. Restriction of water may be neccessary [2].
Nasal suction Useful in infants showing respiratory distress due to nasal blockage [1].
Ventilatory support Consider in infants with severe respiratory distress or apnoea [1].
Chest physiotherapy This is not recommended [1]. However it may be used in infants receiving intensive care [3].
Take steps to prevent nosocomial spread of bronchiolitis Hand decontamination with alcohol based rubs: Essential step to prevent the nosocomial spread of Respiratory Syncytial virus (RSV) [1]. Health education: Educating the family members and care givers on hand sanitation can reduce the nosocomial spread of RSV [1].
Health education to mother and other family members Education on breast feeding and preventing the child from exposure to passive smoking is important in reducing the child's risk of having lower respiratory tract infections in the future [1].
References
  1. Subcommittee on Diagnosis and Management of Bronchiolitis: American Academy of Pediatrics. Pediatrcs [Online]. American Academy of Pediatrics. 2006, vol. 118, 1774-93 [viewed 02 March 2014]. Available from: DOI: 10.1542/peds.2006-2223.
  2. GOZAL, D., M. JAFFE, A. A. COLIN, L. KAHANA, Z. HOCHBERG. The water-electrolyte endocrine balance in infants with bronchiolitis. Pediatric research [Online]. International Pediatric Research Foundation.1988, 24, 545–545 [viewed 05 March 2014]. Available from: doi:10.1203/00006450-198810000-00188.
  3. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf

Management - Specific Treatments

Fact Explanation
Therapy with bronchodilators Not recommended for treatment of acute bronchiolitis in infants [1]. However a trial of alpha or beta adrenergic mediaction can be tried and it should only be continued if there is a documented positive response [2].
Therapy with antivirals (Ribavarin) Not recommended to be used routinely in bronchiolitis [2].
Therapy with corticosteroids Not recommended to be used routinely in bronchiolitis [2].
Therapy with antibiotics Not recommended to be used routinely [1]. Should only be used in infants with co-existing bacterial infection, in the same manner as in the absence of bronchiolitis [2].
Therapy with nebulized epinephrine Not recommended to be used routinely in bronchiolitis [1].
Prophylaxis with Palivizumab May be used in selected infants with bronchopulmonary dysplasia, history of prematurity (less than 35 weeks gestation) or congenital heart diesease [2].
References
  1. Bronchiolitis in children: A national clinical guideline. Scottish intercollegiate guidelines network, 2006 [viewed 02 March 2014]. Available from: http://sign.ac.uk/pdf/sign91.pdf
  2. Subcommittee on Diagnosis and Management of Bronchiolitis: American Academy of Pediatrics. Pediatrcs [Online]. American Academy of Pediatrics. 2006, vol. 118, 1774-93 [viewed 02 March 2014]. Available from: DOI: 10.1542/peds.2006-2223.