A 55-year-old woman with a history of inflamatory bowel disease is admitted to the hospital due to perforated appendicitis. The patient quickly develops respiratory difficulty, and acute respiratory distress syndrome is diagnosed. She is intubated and mechanically ventilated with positive pressure ventilation. Despite the use of high positive end-expiratory pressure, the patient's condition continues to deteriorate. She is intermittently placed in the prone position while mechanically ventilated. Which of the following is most likely to occur due to this position change?

Question

A 55-year-old woman with a history of inflamatory bowel disease is admitted to the hospital due to perforated appendicitis.  The patient quickly develops respiratory difficulty, and acute respiratory distress syndrome is diagnosed.  She is intubated and mechanically ventilated with positive pressure ventilation.  Despite the use of high positive end-expiratory pressure, the patient's condition continues to deteriorate.  She is intermittently placed in the prone position while mechanically ventilated.  Which of the following is most likely to occur due to this position change?

Quizplus · Accepted Answer

Eductional Objective: Prone positioning may be used to improve arterial oxygenation in patients with severe acute respiratory distress syndrome.  The improvement likely results from reduced compression of the posterior lung segments, where the majority of alveoli are located.  This leads to more evenly distributed ventilation throughout the lungs with reduced intrapulmonary shunting and improved ventilation-perfusion matching.

A 55-Year-Old Woman with a History of Inflamatory Bowel Disease