A 40-year-old man comes to the physician because of a 2-year history of gradually worsening shortness of breath. He smoked half a pack of cigarettes daily for 10 years but stopped 8 years ago. His pulse is 72/min, blood pressure is 135/75 mm Hg, and respirations are 20/min. Examination shows an increased anteroposterior diameter of the chest. Diminished breath sounds are heard on auscultation of the chest. Chest x-ray shows widened intercostal spaces, a flattened diaphragm, and bilateral basilar hyperlucency. Echocardiography reveals moderate dilation of the right ventricle and increased central venous pressure. The absence of peripheral edema in this patient is best explained by which of the following compensatory mechanisms?

Question

A 40-year-old man comes to the physician because of a 2-year history of gradually worsening shortness of breath. He smoked half a pack of cigarettes daily for 10 years but stopped 8 years ago. His pulse is 72/min, blood pressure is 135/75 mm Hg, and respirations are 20/min. Examination shows an increased anteroposterior diameter of the chest. Diminished breath sounds are heard on auscultation of the chest. Chest x-ray shows widened intercostal spaces, a flattened diaphragm, and bilateral basilar hyperlucency. Echocardiography reveals moderate dilation of the right ventricle and increased central venous pressure.  The absence of peripheral edema in this patient is best explained by which of the following compensatory mechanisms?

Quizplus · Accepted Answer

Eductional Objective: Peripheral edema results from the accumulation of fluid in the interstitial spaces.  Factors that promote edema include elevated capillary hydrostatic pressure, decreased plasma oncotic pressure, and impaired lymphatic drainage.  In chronic heart failure, increased lymphatic drainage initially offsets factors favoring edema, temporarily delaying edema development.

A 40-Year-Old Man Comes to the Physician Because of a 2-Year