Final answer:
The priority intervention for a client with a UTI is administering an antibiotic since it treats the root cause of the infection. Supportive measures such as pain relief and fluid intake are secondary to the need for an appropriate antibiotic.
Step-by-step explanation:
In caring for a client with a urinary tract infection (UTI), the priority intervention by the nurse would be Option 4: Administering an antibiotic. Antibiotics are the mainstay treatment for UTIs to eradicate the causative bacteria, such as Escherichia coli or other pathogens responsible for the infection. Strong evidence suggests that bacteria from the lower gastrointestinal tract, often introduced to the urinary tract, cause these infections. In the case provided, the antibiotic ciprofloxacin was prescribed and is a common choice for treating UTIs. While administering pain medication, encouraging fluid intake, and providing a warm blanket are supportive measures that can alleviate symptoms and discomfort, they do not address the root cause of the infection. Therefore, the administration of an antibiotic should take priority to ensure effective treatment of the UTI.