Inhaled objects are more likely to enter the right lung for several reasons. First the right bronchus is shorter, wider and more vertical than the left bronchus. Also, the carina (a ridge-like structure at the point of tracheal bifurcation) is set a little towards the left. The terminal bronchiole is a very small space and impossible for the seed to lodge here.

The prognosis for croup is excellent, and recovery is almost always complete with complications being quite rare. The possible complications are pneumonia, bacterial tracheitis, pulmonary oedema, pneumothorax, pneumomediastinum, lymphadenitis or otitis media. Bacterial tracheitis is a life-threatening infection that can arise after the onset of an acute viral respiratory infection.

Arterial blood gas is useful for the evaluation of oxygen and carbon dioxide gas exchange, respiratory function including hypoxia, and acid/base balance. This will quickly indicate if assisted ventilation is required for this patient.

Recurrent bacterial infections may be due to lack of B-cell function, consequently resulting in a lack of gamma globulins production. Once the maternal antibodies have depleted, the disease manifests with greater severity and is called x-linked agammaglobulinemia also known as ‘X-linked hypogammaglobulinemia’, ‘XLA’ or ‘Bruton-type agammaglobulinemia. it is a rare x linked genetic disorder that compromises the bodies ability to fight infections.
Acute leukaemia causes immunodeficiency but not so specific.
DiGeorge syndrome is due to lack of T cell function.
Aplastic anaemia and EBV infection does not cause immunodeficiency.

The x-ray is suggestive of bronchiectasis. The most probable aetiology especially considering recurrent chest infections at such a young age is cystic fibrosis.

One-third of patients with Guillain-Barre syndrome suffer from diaphragm weakness which can lead to further respiratory complications if there is involvement of the tongue, palate, and neck muscles. Forced vital capacity (FVC) is the best way to monitor respiratory muscle function by assessing it repeatedly. Admission for ITU is suggested when FVC is below 20ml/kg and intubation recommended when FVC is 15ml/kg or below. FVC is used in any neurological disorders wherein the respiratory muscles are affected.

Acute epiglottitis is a life-threatening disorder with serious implications to the anaesthesiologist because of the potential for laryngospasm and irrevocable loss of the airway. There is inflammatory oedema of the arytenoids, aryepiglottic folds and the epiglottis| therefore, supraglottitis may be used instead or preferred to the term acute epiglottitis.Acute epiglottitis can occur at any age. The responsible organism used to be Hemophilus influenzae type B (Hib), but infection with group A b-haemolytic Streptococci has become more frequent after the widespread use of Hemophilus influenzae vaccination. The typical presentation in epiglottitis includes acute occurrence of high fever, severe sore throat and difficulty in swallowing with the sitting up and leaning forward position in order to enhance airflow. There is usually drooling because of difficulty and pain on swallowing. Acute epiglottitis usually leads to generalized toxaemia. The most common differential diagnosis is croup and a foreign body in the airway. A late referral to an acute care setting with its serious consequences may result from difficulty in differentiation between acute epiglottitis and less urgent causes of a sore throat, shortness of breath and dysphagia.

Asthma patients have an increased risk of developing complications like pneumonia or collapsed lung. A clear visualization of the lungs through a CXR will define the management necessary for this patient.

The characteristic cells in granulomatous inflammation are giant cells, formed from merging macrophages and epithelioid cells elongated with granular eosinophilic cytoplasm. Granulomatous reactions are seen in patients with tuberculosis. A tuberculous/caseating granuloma is characterised by a zone of central necrosis lined with giant multinucleated giant cells (Langhans cells) and surrounded by epithelioid cells, lymphocytes and fibroblasts. The caseous zone is present due to the damaged and dead giant cells and epithelioid cells.
Mast cells are only few in number and fibroblasts lay down collagen.
Basophils are not present.
The giant cell made up of macrophages are the most abundant cells in this inflammatory process.

The patient history suggests a spontaneous tension pneumothorax which is a life-threatening situation in which excess air is introduced into the pleural space surrounding the lung. When there is a significant amount of air trapped in the pleural cavity, the increasing pressure from this abnormal air causes the lung to shrink and collapse, leading to respiratory distress. This pressure also pushes the mediastinum (including the heart and great vessels) away from its central position, e.g. deviated trachea, and diminishing the cardiac output. Tension pneumothoraxes cause chest pain, extreme shortness of breath, respiratory failure, hypoxia, tachycardia, and hypotension. These are definitively managed by insertion of a chest tube. However, in the emergency setting temporizing measures are needed while chest tube materials are being gathered. In these situations, urgent needle thoracostomy (also called needle decompression) is performed.