Which parameter is essential to monitor with an indwelling catheter?

• A. Blood pressure
• B. Urine output
• C. Blood glucose
• D. Respiratory rate

Answer: (B)

Monitoring urine output is the essential parameter with an indwelling catheter because the catheter directly drains urine from the bladder, making the amount that is produced and collected a real-time read on kidney function and fluid balance. Regularly tracking hourly urine output helps spot problems early: low output can indicate dehydration, reduced kidney perfusion, bladder outlet obstruction, or acute kidney injury, while very high output can point to diuresis or certain endocrine/renal issues. This measurement directly informs fluid management and patient safety. Other parameters like blood pressure, blood glucose, or respiratory rate are important for overall condition, but they don’t directly reflect the catheter’s drainage or the kidneys’ current function, so they aren’t the essential monitoring focus in this context.