A 25-year-old male with a long history of severe asthma presents to the emergency room with shoness of breath. He has previously required admission to the hospital and was once intubated for asthma. Which of the following findings on physical exam would indicate a benign course?
High-Yield Explanation
(Stobo, 23/e, p 143.) It is extremely impoant to accurately determine the severity of an exacerbation of asthma, since the major cause of death from asthma is the underestimation of the severity of a paicular episode by either the patient or the physician. Silent chest is a paicularly ominous finding, because the airway constriction is so great that airflow is insufficient to generate wheezing. Hypercapnia and thoraco- abdominal paradox are almost always indicative of exhaustion and respiratory muscle failure or fatigue and generally need to be aggressively treated with mechanical ventilation. An increased pulsus paradoxus may also be a sign of severe asthma, as it increases with greater respiratory effo and generation of more negative intrathoracic pressures during inspiration However, a pulsus paradoxus of up to 8 to 10 mmHg is considered normal; thus, a value of 5 mmHg would not be indicative of a severe episode of asthma.