A child with asthma has the following medication ordered: Theophylline 4 mg/kg/dose every 6 hrs. The child weighs 4.69 kg. Calculate the appropriate dose.

A. Methylprednisolone: Methylprednisolone is a corticosteroid used for long-term management and prevention of asthma exacerbations. It has anti-inflammatory effects and is not typically used for immediate relief during an acute asthma attack.

B. Albuterol: Albuterol is a short-acting beta-agonist bronchodilator, which is the first-line medication for relieving acute bronchoconstriction during an asthma attack. It works quickly to open the airways and improve breathing.

C. Fluticasone: Fluticasone is an inhaled corticosteroid used for long-term asthma control and prevention of symptoms. It has anti-inflammatory effects but is not used for immediate relief during an acute asthma attack.

D. Beclomethasone: Beclomethasone is also an inhaled corticosteroid used for long-term asthma control and prevention of symptoms. Like fluticasone, it is not used for immediate relief during an acute asthma attack.

A. Pulmonary function test:

Pulmonary function tests (PFTs) assess lung function by measuring airflow, lung volume, and gas exchange. While PFTs can provide valuable information about respiratory function, they are not specific to cystic fibrosis and may show abnormalities consistent with various respiratory conditions. However, PFTs are often performed in individuals with cystic fibrosis to monitor lung function over time and assess response to treatment. They are not considered the most definitive test for diagnosing cystic fibrosis.

B. Sweat chloride test:

This option is correct. The sweat chloride test is considered the most definitive diagnostic test for cystic fibrosis. It measures the concentration of chloride in sweat, which is typically elevated in individuals with cystic fibrosis due to defective chloride transport in sweat glands. A sweat chloride concentration above a certain threshold (usually ≥60 mmol/L) is diagnostic of cystic fibrosis, particularly when confirmed with repeat testing.

C. Stool fat content analysis:

Stool fat content analysis evaluates fat absorption and fecal fat excretion, which may be impaired in individuals with cystic fibrosis due to pancreatic insufficiency. However, while stool fat content analysis can provide supportive evidence of malabsorption in cystic fibrosis, it is not considered the most definitive test for diagnosing the condition. Stool fat content analysis is often used in conjunction with other diagnostic tests to assess pancreatic function and nutritional status in individuals with cystic fibrosis.

D. Sputum culture:

Sputum culture involves culturing respiratory secretions to identify bacterial pathogens, which can be useful for diagnosing respiratory infections in individuals with cystic fibrosis. However, sputum culture is not specific to cystic fibrosis and may show similar findings in other respiratory conditions. While respiratory cultures are important for guiding treatment in cystic fibrosis, they are not considered the most definitive test for diagnosing the condition.