BRONCHIOLITIS BY: NICOLE STEVENS

Objectives Discuss the pathophysiology of bronchiolitis Identify the risk factors Identify the causative agents Describe the clinical signs and symptoms Discuss assessment of the child and determination of severity Discuss medical and nursing management Discuss possible investigations Discuss medications that may be used Discuss infection control measures

Pathophysiology Viral, lower respiratory tract infection Causes swelling of the mucosa Bronchi and bronchiole walls are infiltrated with inflammatory cells The lumina are obstructed on expiration Widespread, small-airway narrowing due to oedema resulting in air trapping and inadequate oxygenation of pulmonary blood flow

Pathophysiology Dilation of the bronchial passages on inspiration allows for adequate space for intake of air In contrast the narrowing of the air passages on expiration prevents air from leaving the lungs Resulting in over inflation of the lungs Self-limiting condition, but can be life threatening particularly in premature infants and those with underlying respiratory, cardiac, neuromuscular and immunological conditions. Same concept as what happens with mec aspiration syndrome

Pathophysiology

Risk Factors Generally affects children under 12 months of age Most frequent cause of hospitalisation in children under 6 months of age Usually occurs in winter and spring More boys are usually affected than girls Exposure to cigarette smoke Attendance at child care facilities Having older siblings Not being breastfed

Causative Agents Usually respiratory syncytial virus (RSV), in approximately 80% of cases Less common: metapnuemovirus, adenovirus, parainfluenza, rhinovirus Human Metapnuemovirus (hMPV): similar to RSV, cold like symptoms Adenoviruses: very common, about 50 subtypes, symptoms of common cold, conjunctivitis, tonsillitis, ear infections, sore throat Parainfluenza: leading cause of croup; can cause encephalitis (inflammation of the brain), menigitis (inflammation of the tissues surrounding the brain and the CNS)

Signs & Symptoms Cough Tachypnoea Wheeze Crackles Poor feeding Hyperinflation Apnoea Low grade fever

Assessment Take a history: Age (higher risk if less than 6 wks old) Duration of symptoms (peak severity is typically day 3 – 5 of illness, so is the child likely on the improve, or is the worse still to come) Any apnoeas (number, frequency, duration) Colour (pink, pale, cyanotic, grey) Feeding (able to suck at breast/bottle, tolerating?)

Assessment cont... Physical appearance: Colour, general observations, WOB Behaviour (irritable, exhausted) Hydration (tissue turgor, capillary refill, peripheral circulation) Auscultation of chest (typically reveals end expiratory crackles and/or wheeze) Observe feeding (monitor SaO2 during)

Assessment of Severity MILD MODERATE SEVERE Behaviour Normal Some/intermittent irritability Increasing irritability and/or lethargy Respiratory Rate Increased Resp rate Tracheal Tug Nasal Flaring Marked increase or decrease Tracheal Tug Nasal Flaring Accessory Muscle Use None or minimal Moderate chest wall retraction Marked chest wall retraction Feeding May have difficulty with feeding or reduced feeding Reluctant or unable to feed Oxygen No oxygen requirement (Sa02 > 93%) Mild hypoxemia corrected by oxygen** (Sa02 90 - 93%) Hypoxemia, may not be corrected by oxygen** (Sa02 < 90%) Apnoeic episodes None May have brief apnoeas May have increasingly frequent or prolonged apnoeas

Management Severity (mild): manage at home, small frequent feeds, see GP in 24 hours Severity (moderate): admit; give O2 PRN; consider IVT at 75% maintenance (potential for syndrome of inappropriate ADH secretion); 1 – 2 hrly observations Severity (severe): admit; consider CPAP or ventilation; continuous cardiorespiratory monitoring ADH: antidiuretic hormone

Nursing management Minimal handling, cluster cares Reduce the lighting and noise levels Promote rest and position comfortably Observations as required Feeds/fluids: may be a combination of IV fluids or milk feeds (depends on babies WOB, tolerance, risk of aspiration, secretions etc) Comfort feeds if mainly on IVT PRN normal saline nasal drops/suction to remove secretions Manage oxygen therapy/respiratory support as prescribed. Studies at RCH are inconclusive as to whether milk feeds via NGT is preferential or not to IV fluids.

Investigations In most children with brochiolitis no investigations are required; if there is uncertainty of diagnosis an NPA may be taken and a chest x-ray (in case of bronchiolitis will typically show hyperinflation, peribronchial thickening, and patchy areas of consolidation and collapse). Blood tests: daily U&E if on IV fluids Blood culture only taken if other diagnosis suspected Blood gas not routine, decision to ventilate would be made on clinical signs

Investigations An xray of a child RSV showing the typical bilateral perihilar fullness of bronchiolitis Hilar (area above and around heart)

Medications Consider bronchodilators in child > 6 months Consider regular salbutamol if there is a positive response Don’t continue bronchodilators if no response to initial dose Paracetamol for comfort/pain relief Oral sucrose for painful procedures Above and behind the cardiac impression (where the heart sits in relationship to the lungs) is a triangular depression named the HILUM, where the structures which form the root of the lung enter and leave the viscus. These include the pulmonary artery, the superior and inferior pulmonary veins, lymphatic vessels and the bronchus, with bronchial vessels surrounding it. The area around the hilum is called "perihilar". Congestion is fluid or exudates (pus) in this region...that have infiltrated from surrounding tissue.

Infection Control Droplet and contact precautions, spread by infective secretions Incubation 2 – 8 days Course of illness 7 – 10 days Virus can live for 4 hours on benchtops Infants with bronchiolitis may be cohorted together Patients with suppressed immunity, underlying respiratory disease and infants less than 2 years of age should not be nursed in the same room as infants with bronchiolitis

References “Brochiolitis – ongoing management” www.rch.org.au