A 68-year-old man with bilateral percutaneous nephrostomy tubes is brought to the emergency department by his wife because of altered mental status. The wife says that he is "not his usual self" and responded with nonsensical phrases when she awoke him for breakfast. He appears uncomfortable and diaphoretic. He is oriented to person but not to place or time. His temperature is 36.8°C (98.2°F), pulse is 124/min, respirations are 22/min, and blood pressure is 76/50 mm Hg when supine. Pulse oximetry on room air shows an oxygen saturation of 96%. In the emergency department, a central venous catheter is placed and hemodynamic monitoring shows: Which of the following is the most likely cause of this patient's hypotension?

Question

A 68-year-old man with bilateral percutaneous nephrostomy tubes is brought to the emergency department by his wife because of altered mental status. The wife says that he is "not his usual self" and responded with nonsensical phrases when she awoke him for breakfast. He appears uncomfortable and diaphoretic. He is oriented to person but not to place or time. His temperature is 36.8°C (98.2°F), pulse is 124/min, respirations are 22/min, and blood pressure is 76/50 mm Hg when supine. Pulse oximetry on room air shows an oxygen saturation of 96%. In the emergency department, a central venous catheter is placed and hemodynamic monitoring shows:  Which of the following is the most likely cause of this patient's hypotension?

Quizplus · Accepted Answer

Eductional Objective: Septic shock can present with either hyper- or hypothermia.  The initial disturbance is peripheral vasodilation leading to decreased systemic vascular resistance, decreased central venous pressure, and decreased pulmonary capillary wedge pressure.  A compensatory increase in sympathetic drive causes an increase in cardiac output; the resulting high flow rates lead to incomplete oxygen extraction in the tissues, resulting in high mixed venous oxygen saturation.

A 68-Year-Old Man with Bilateral Percutaneous Nephrostomy Tubes Is Brought