Standard Ostomy Bag Capacity
The provided evidence does not specify the exact physical capacity (volume) of standard ostomy bags, as this is a manufacturing specification rather than a clinical guideline parameter.
What the Evidence Does Tell Us About Ostomy Output and Bag Management
Ileostomy Bags
- Ileostomy bags require emptying 3-4 times daily due to liquid effluent production 1, 2
- Normal ileostomy output is less than 1.5 L/day (approximately 1500 mL), which guides the functional capacity needs 2
- The wafer/appliance typically requires changing every 4 days on average 1
- High output is defined as greater than 1.5 L/day, and outputs exceeding 2000 mL/24h place patients at high risk for dehydration and electrolyte depletion 2
Colostomy Bags
- Colostomy bags require changing once every 6-7 days due to formed stool output 1, 2
- Output typically consists of formed stool occurring once daily, making management easier than ileostomy 1, 2
- The less frequent emptying requirement reflects both the consistency of output and the bag's functional capacity 2
Clinical Implications for Bag Selection
The key clinical consideration is matching bag capacity to output type and volume rather than a universal "standard" size:
- Drainable bags are used for ileostomies and urostomies due to liquid/semi-liquid output requiring multiple daily emptyings 3
- Closed bags are used for colostomies with formed stool that can be changed as a complete unit 3
- Bags must accommodate the expected daily output while allowing for emptying before reaching full capacity to prevent leakage 1
Important Caveat
Bag capacity must prevent overfilling, as leakage is one of the most common and problematic stomal complications, particularly with liquid effluent from ileostomies 1, 4. Factors predisposing to leakage include obesity, placement within skin creases, loop configuration, and liquid effluent 1.