From the Guidelines
Normal urine output is generally considered to be at least 100 mL per 24 hours, as stated in the context of peritoneal dialysis adequacy 1. When considering the broader context of kidney function and overall health, normal urine output for adults typically ranges from 800 to 2000 milliliters (ml) per day. This amount can vary based on several factors including:
- Fluid intake
- Environmental conditions
- Individual health factors For monitoring purposes, a commonly used guideline is that output should be at least 30 ml per hour or 720 ml per day as a minimum threshold for adequate kidney function. Key factors that influence urine production include:
- Hydration status
- Medication use
- Overall health Decreased output, such as oliguria (below 500 ml per day) or anuria (less than 100 ml per day), may indicate kidney dysfunction or other medical issues requiring attention, as noted in the study on peritoneal dialysis adequacy 1. Conversely, excessive urination can result from conditions like diabetes or certain medications. Monitoring urine output is particularly important in certain patient groups, such as hospitalized patients, those with kidney disease, or individuals taking medications that affect kidney function, as it provides valuable information about hydration status and kidney health 1.
From the Research
Definition of Normal Urine Output
- Normal urine output is typically defined as 0.5 to 1 ml/kg/hour in adults 2
- However, urine output can vary depending on factors such as fluid intake, age, and medical conditions
Urine Output Categories
- Urine output can be categorized into three groups:
- UO > 0.5 ml/kg/hour
- UO 0.3-0.5 ml/kg/hour
- UO ≤ 0.3 ml/kg/hour 2
- These categories can be used to predict hospital mortality, with lower urine output associated with higher mortality rates
Abnormal Urine Output
- Polyuria is defined as a urine output of more than 3 L in 24 hours 3
- Oliguria is defined as a urine output of less than 0.5 ml/kg/hour 4
- Abnormal urine output can be an indicator of underlying medical conditions, such as acute kidney injury or fluid overload