Medical Pathologies of Respiratory system
Bronchiolitis is a common lower respiratory tract infection that affects babies and
young children. The early symptoms are similar to those of a common cold, such
as runny nose or cough.
Causes of bronchiolitis
Bronchiolitis is usually caused by a viral infection. Many different viruses can be the
culprit, including the flu, but the most common in children is what’s called respiratory
syncytial virus.
Outbreaks of this virus happen every winter. They may only get mild symptoms, but
in severe cases it can cause bronchiolitis or pneumonia
Pathophysiology overview
The pathophysiology of bronchiolitis begins with an acute infection of the epithelial
cells lining the small airways within the lungs. Such infection results in edema,
increased mucus production, and eventual necrosis and regeneration of these cells.
The inflammation, edema, and debris result in obstruction of bronchioles, leading
to hyperinflation, increased airway resistance, atelectasis, and ventilation-perfusion
mismatching. Bronchoconstriction has not been described. Infants are affected
most often because of their small airways, high closing volumes, and insufficient
collateral ventilation. Recovery begins with regeneration of bronchiolar epithelium
after 3-4 days; however, cilia do not appear for as long as 2 weeks. Mucus plugs
are instead predominantly removed by macrophages.
The pathogenesis of bronchiolitis involves a combination of airway edema,
increased mucus production, and necrosis of airway epithelial cells due to direct
cytotoxic injury. Respiratory syncytial virus transmission occurs from person to
person either by direct inoculation of nasal mucosa with contaminated secretions
or by inhalation of large infectious droplets. Virus replicates in the nasal epithelium,
and an exaggerated immune response occurs, with an influx of natural killer cells,
lymphocytes, and granulocytes into the epithelium. After an incubation period of 4
to 6 days from transmission, upper respiratory tract symptoms appear, including
nasal congestion and rhinorrhea.
Signs and symptoms
The most common signs and symptoms of bronchiolitis are: runny nose, fever,
stuffy nose, loss of appetite and cough are the first signs of the infection. Symptoms
may worsen after a few days and may include wheezing, shortness of breath, and
worsening of the cough. The child might show more severe signs, including:
• Making grunting noises.
• Having trouble sucking and swallowing, this makes feeding difficult on top of
having a poor appetite.
• Trying so hard to breathe that the chest retracts (the skin is drawn down
tightly against the rib cage and looks like it is going inward).
• Turning blue or gray in the lips, fingertips or toes.
• Being sluggish.
Investigations
The diagnosis of bronchiolitis is mainly based on clinical manifestations. Pulse
oximetry is useful if hypoxia is suspected. It is not unusual for these infants to
experience mucous plugs leading to hypoxia. If supplemental oxygen is required,
the goal should be to maintain saturation levels between 90 and 100%.
Beyond the physical exam, the following diagnostic tests might be done:
• Laboratory: Full blood count (FBC), white blood cells are increased (Normal
range: 4000-11000/mm3), chain reactive protein might be positive and
increased (Normal range: 6.8-820 mcg/dL), neutrophils are increased (Normal range: 0-8%), increased erythrocyte sedimentation rate (Normal value: <30
mm/hr).
• Chest Radiograph: A chest radiograph is indicated if pneumonia, a chest
mass, a foreign body, or heart failure are suspected. In bronchiolitis, the
radiograph may show hyperinflation or scattered areas of atelectasis. This is
can be misinterpreted as bacterial pneumonia.
• Nasal Specimen: A nasal aspirate for antigen detection of respiratory
syncytial can be performed. Influenza A and B and adenovirus can also be
detected by this method.
Adequate medical diagnosis of bronchiolitis
The diagnosis of bronchiolitis is made primarily based on history and physical
examination findings. A mucus sample test (where a sample of mucus from your
child’s nose will be tested to identify the virus causing their bronchiolitis) urine or
blood tests. A pulse oximeter test (where a small electronic device is clipped to the
child’s finger or toe to measure the oxygen in their blood) must be performed.
Treatment plan of bronchiolitis
The physician has the role to diagnose and prescribe the medication according
the signs and symptoms, also the results of investigation done; the physician
orders the following medications according the medical decision and guideline:
Bronchodilators. Bronchodilators are frequently tried in infants presenting with
wheezing due to bronchiolitis because of its similarity to asthma, Anticholinergic
agents, Corticosteroids, Ribavirin, Antibiotics, Surfactant, Heliox.
Treatment at home:
• Keep the child upright. Keeping the child upright may make it easier for them
to breathe, which may help when they are trying to feed.
• Make sure the child drinks plenty of fluids.
• Do not smoke at home.
• Relieving a fever.
• Saline nasal drops.
Symptomatic care: There is no cure for bronchiolitis, so treatment is aimed at
the symptoms (eg, difficulty breathing, fever). Treatment at home usually includes
making sure the child drinks enough and saline nose drops (with bulb suctioning
for infants).
Nursing management:
Provide oxygen if saturations are low, Assist with oral hydration, Listen to the lungs,
Monitor oxygenation, Assess vitals, Intake and output, IV (intravenous) fluids if the child can’t drink well, Extra oxygen and a breathing machine (ventilator) to help
with breathing, Frequent suctioning of the child’s nose and mouth if respiratory tract
secretions, Breathing treatments, as prescribed.
Evolution and complications of bronchiolitis
In most cases, the disease is mild and self-limited. With bronchiolitis, as any other
diseases, various complications are possible. If the child develops complications from
bronchiolitis, it’s likely that they’ll need hospital treatment. Potential complications
of bronchiolitis include:
• Respiratory failure
• Pneumonia
• Dehydration