Case Study
The patient is a 66-year-old man with chronic respiratory fibrosis who has been treated with
antibiotics (penicillin [Ampicillin] followed by azithromycin [Zithromax]) for a bacterial
pneumonia for the past 3 weeks.
He was admitted from the ED because his Sp
O
2
was 85%.
In addition to an antibiotic, he also takes losartan (Cozaar) 50 mg daily, prednisone 10 mg daily,
and sertraline (Zoloft).
When he gets to the unit, he is slow to answer questions although his answers are correct, and
he cannot remember the name of the physician who saw him in the ED.
When his blood work comes back, you notice that his serum sodium is 109 mEq/L and his
hematocrit is 32%.
He is supposed to provide a clean-catch urine specimen but has not urinated since his admission,
3 hours ago.
Questions:
1. What is the probable source or sources of his mental slowness?
2. What risk factors does he have for SIADH?
3. What other assessment data should you obtain immediately? Provide a rationale for your selection.
4. His admitting prescription reads that he should receive 500 mL of D5% in Ringer’s lactate IV over the
next 2 hours. What should you do about this prescription?
