Question

Jackson is a 12-year-old patient with a diagnosis of moderate asthma. He comes into the office stating he has had to increase usage of his rescue inhaler over the past week ever since the weather warmed up. He denies any fever or mucus production but does report a dry cough. The nurse checks his vital signs and even though his respirations are unlabored at the moment, his resting O2 saturation is 91%.

Discussion 9.1

Clearly identify the etiology of asthma. Describe the pathophysiologic effects of poor ventilation in the asthma patient. Discuss the relationship between ventilation and perfusion. Explain the pathophysiologic mechanisms that are contributing to Jackson's low O2 saturation.

Answer 1

Asthma is common chronic disease of childhood.Sex affects the development of asthma in a time-dependent manner. Until age 13–14 years, the incidence and prevalence of asthma are greater among boys than among girls(Marco R et.al).In childhood, airway hyperresponsiveness is more common and more severe among males.(Souef et.al).Weather factors such as humidity and temperature can affect how many allergens and irritants are being carried in the air and inhaled by child.The rescue inhaler has side effects leading to dry cough, throat irritation.

The underlying pathology of asthma is reversible and diffuse airway inflammation .The inflammation leads to obstruction by reducing airway ,contraction of bronchial smooth muscle (bronchospasm) dimininishing airway size .The obstruction of airway results in hypoxemia .(Smeltzer.2004).His low oxygen saturation may be due to narrowing of airway because of more use of inhaler.

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