by Christine on September 15th, 2011
filed under Gastric Banding Surgery
My blog reader Kris was able to link me to an article explaining why our gastric bands feel tighter when we are stressed (or PMSing). How very interesting! The article can be found here. The answer is that the gastric band is a semi-permeable membrane that actually can absorb fluids in the body!
Often times patients will come in because their Lap-band feels too tight. They find more difficulty with some foods, and are uncomfortable. They ask me “does stress cause the band to tighten?” The answer is, yes, it does.
The biology of stress is this: when you have stress, be it physical stress (like an illness) or mental stress (like your mother-in-law coming by for a short two week visit)…the body reacts by retaining fluid. You may notice that wedding rings are tighter, and there is more swelling in the legs at night.
The balloon of the adjustable Lap-band is a semi-permeable membrane, meaning it is osmotically active. In plain English: the more water you retain, some is transmitted to the band, so it swells.
If a patient has 5.5 cc in their band (we measure it) and they come in and it feels tighter, we find they have 6 cc in the band. Where did the ½ cc come from? That is from the extra water the body is carrying. Since the balloon on the band is semi-permeable it will retain more water also.
This is the same reason that most people find the Lap-band to be tighter in the morning. In the evening you may notice you have some swelling of your ankles – by gravity your body water has gone down to the legs. In the morning that swelling is gone, and the water has gone back to the central compartment of the body where the band is. If we measure the band in the morning it can have 0.25 to 0.5 cc more in it (which can make a difference).
This is also why we don’t like bands being too tight. People need room for stress – of all kinds. Leaving room in the band to allow for this, means that patients will have fewer difficulties.
Upon further web searching, I see that there are several scientific studies that have been performed that have verified this claim, such as this one here.
This knowledge makes me realize two things: (1) When your band is too tight or too loose, don’t go running to your doctor to get it fixed right away. Give it a little time to see if the saline levels balance themselves back out. Also, (2) If you experience a “looser” band, it doesn’t necessarily mean that your band is leaking or is broken. First try increasing your fluid consumption and see if that fixes the problem. If there is a noticeable decrease in “restrictive feeling,” then go see your doctor.