This topic is about preparing for a colostomy reversal surgery, specifically focusing on the transition from using closed pouches to drainable ones during the pre-operative bowel preparation. The person is seeking advice on how many drainable pouches to have on hand and other related preparations. Here are some helpful insights and advice:

1. Quantity & Preparedness
- Expect a high-volume, watery output during the bowel prep, which can be quite intense. It's wise to plan for the worst-case scenario by obtaining a full box of approximately 10 drainable pouches. Any unused pouches can be donated afterward.
- Keep extra supplies handy, especially at night, as blowouts are more likely to occur then.

2. Product & Accessory Suggestions
- Recommended Hollister drainable systems include the 18183 (12-inch) and 18194 models.
- To help contain leaks, consider using a CeraPlus (Cera) O-ring, flange mount, belt, and optional C-shaped strip extenders.
- Instead of pouches, you might consider using irrigation sleeves, such as the 3-foot Hollister sleeves. These attach to the same wafer, hold very large volumes, are easy to rinse, and significantly reduce the risk of blowouts.

3. Emptying Strategy
- During the bowel prep, sit on the toilet with the pouch’s tail open and let the output run directly into the bowl. Using a comfortable elongated toilet, like a Toto ADA, can make this process easier.

4. Disposal / Donation
- Any leftover supplies after the surgery can be donated to others or to ostomy supply donation programs, helping those in need.

The person is also preparing for surgery with additional pre-op activities such as hypnotherapy for anxiety, acupuncture for abdominal fluid, and physical therapy for core exercises.