A 78-year old woman was hospitalized 4 days ago after sustaining a left hip fracture due to a fall. She underwent surgical repair with right hip replacement 3 days ago and did not fully awake from general anesthesia until 12 hours after extubation. As her alertness has increased, she has become increasingly agitated. The patients history reveals a 4 year history of Alzheimer dementia. She has no other pertinent personal or family medical history. Current medications include: donepezil, memantine, and low molecular weight heparin.
On physical exam her temperature is 37.2 C, blood pressure is 100/66 mmHg, pulse rate is 100/min and regular and respiration rate is 18/min. The patient can move all four limbs with guarding of the right lower limb. She is inattentive and disoriented to time and place and exhibits combativeness alternating with hypersomnolence. The remainder of the neurologic examination is unremarkable, without evidence of focal findings or meningismus.
Which is the most likely diagnosis?
- Acute stroke
- Acute worsening of Alzheimer dementia
- Post operative delirium
- Pulmonary embolus
- Post operative infection