<prompt> A 62-year-old man with a 40-packyear history of smoking presents with increased sputum production and marked SOB. On examination, he is using accessory muscles of respiration, and breath sounds are diminished with expiratory wheezes. Your clinical diagnosis is chronic obstructive pulmonary disease COPD exacerbationFor the above patients, select the characteristic arterial pulse finding.pulsus tarduspulsus paradoxushyperkinetic pulsebisferiens pulse  <response>: Pulsus paradoxus, a drop of 10 mm Hg in systolic blood pressure during inspiration, is caused by pericardial tamponade, airway obstruction, or superior vena cava obstruction. At times, the peripheral pulse may disappear completely during inspiration. 