A patient is admitted to the ED of a local hospital in an ac…

A patient is admitted to the ED of a local hospital in an acute onset of an asthma exacerbation; upon entering the room you note the following: HR = 136, RR = 22, moderate use of accessory muscles, hypertension and SpO2 90% on 3 L/NC. Upon your assessment you note faint expiratory wheezes bilaterally and as you palpate the patient’s pulse you note that it weakens in strength during the patient’s inspiratory phase. Which of the following is causing this finding?