Final answer:
The nurse should question the Fleet enema for a patient with elevated BUN and serum creatinine levels due to its potential nephrotoxic effects and the risk of phosphate nephropathy, which can lead to acute renal failure.
Step-by-step explanation:
The question pertains to which bowel preparation should be questioned for a patient with elevated blood urea nitrogen (BUN) and serum creatinine levels who is scheduled for a renal arteriogram. Given these lab results, the patient's kidney function is impaired. In such cases, certain bowel preparations, particularly those with potential nephrotoxic effects or those that may cause dehydration, should be used with caution or avoided.
The nurse should most likely question the order for a Fleet enema. Fleet enemas contain phosphate, which can be nephrotoxic and may further impair renal function in patients with already elevated BUN and creatinine levels. Moreover, significant absorption of phosphate from Fleet enemas can occur, leading to phosphate nephropathy, a dangerous condition that can result in acute renal failure.
The other options like tap-water enema, Senna/docusate (Senokot-S), and Bisacodyl (Dulcolax) tablets are generally considered safer for patients with renal impairment as they are less likely to cause dehydration or have direct nephrotoxic effects.