Acute Respiratory Distress Syndrome

An 80 year old, frail woman living in a nursing home finishes her dinner and goes to the common room to play dominoes. She vomits and aspirates some of the vomit. She appears to be fine after she stops coughing. She is able to return to her previous level of functioning. Three days later, she reports having a very hard time breathing. She is given oxygen via nasal cannula, which only slightly eases her distress. Over the next 48 hours, her dyspnea worsens and she is sent to the hospital. A chest xray shows bilateral infiltrates and poor aeration. Within hours, she is placed on a ventilator with the diagnosis of Acute Respiratory Distress Syndrome (ARDS).
a. Describe the pathophysiologic processes of ARDS and relate them to this patient. b. State which direction the oxyhemoglobin dissociation curve would shift in this patient and give rationale for your choice. c. Relate how you would change the events described to minimize the chances that she would develop ARDS.