Urine output less than ______ mL/24 hours is known as anuria.?

Appeared in: MP CHO - 2022

Explanation

Anuria is clinically defined as the passage of less than 100 mL of urine in a 24-hour period.
This condition represents a near-complete cessation of urine production by the kidneys.
It is a critical sign that points towards severe underlying issues such as complete urinary obstruction, acute kidney injury (AKI), or end-stage renal disease.

Option A: A urine output of 800 mL in 24 hours is considered within the low-normal range for an adult, not anuria.
Option B: Urine output of less than 500 mL per day (specifically, less than 400 mL) is the definition of oliguria, a less severe condition than anuria.
Option D: An output of 300 mL per day is a clear example of oliguria, which signifies a significant decrease in urine production but not the near-absence that defines anuria.

Visual 1: Chart: Comparison of Normal Urine Output, Oliguria, and Anuria. This visual helps differentiate the specific volume thresholds for each condition, making it easier to remember.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Definitions of abnormal urinary output (Anuria and Oliguria) as background academic context rather than a clinical decision trigger.
Accurate measurement and documentation of urine output are fundamental nursing responsibilities for assessing a patient's fluid balance and kidney function.
A sudden drop in urine output to anuric levels is a medical emergency that requires immediate assessment for causes (e.g., catheter blockage, hypovolemia) and prompt notification of the healthcare provider.
What if? If a patient's 24-hour urine output is 350 mL, the nurse identifies this as oliguria, not anuria. The intervention would be to assess for signs of dehydration, review medications, and report the trend, whereas an output of 80 mL (anuria) would trigger a more urgent response.

How to Approach the Question

This is a factual recall question testing knowledge of specific medical terminology.
Identify the key term in the question stem: 'anuria'.
Mentally retrieve the definitions for different levels of urine output.
Normal adult urine output is approximately 800-2000 mL/day.
Oliguria is defined as urine output of less than 400 mL/day.
Anuria is defined as urine output of less than 100 mL/day.

Concept Tested & Keywords

QmL00XLjNuLcEpmZ1McBRb

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart A (pp 26-201 of 604) p. 201-604

Practise the full MP CHO - 2022

Attempt every question from this paper in a timed mock, then review the full solution for each one.