Re: Fills - band permeability

[Guest guest]

//I wonder the same thing: if years down the road, might you need a

fill or does the band always stay at the same restriction, or does

it loosen up? //

It is not unusual for fluid to be missing from the band. I

don't worry about +/- 1 cc. I cut and pasted the info below

regarding the permeability of the band. It is possible that afer

years, you may need a little adjustment to take you back to

your " sweet spot "

Obes Surg. 2005 May;15(5):624-9.

Permeability of the silicone membrane in laparoscopic adjustable

gastric

bands has important clinical implications. Dixon JB, O'Brien PE.

BACKGROUND: The single most important attribute of the laparoscopic

adjustable gastric band (LAGB) is its adjustability. Having the

correct

volume of fluid within the band is crucial for optimal performance.

We

observe a small reduction of the satiety-promoting effect with time.

The

characteristics and clinical relevance of volume change have not been

adequately investigated. METHOD: One observer measured the saline

volume

within the 10-cm Lap-Band in 118 consecutive patients who fulfilled

the

entry criteria. The same observer had performed and recorded the

previous adjustment. Initial volume, final volume and time between

observations provide the data for analysis. In addition, a range of

adjustable gastric bands currently available were bench-tested to

assess

broad applicability of findings. RESULTS: The difference between

observations varied from 0.0 ml to -1.0 ml, median of -0.1

interquartile

range (IQR) 0.0-0.2 ml. Two factors were associated with volume

change:

time in days between the observations (r = -0.55, P<0.001) and the

initial volume within the band system (r = -0.50, P<0.001). These two

independent factors accounted for a significant proportion of the

variance observed ( and Snell R2 = 0.45, P<0.001). Replacement of

any

discrepancy appears to maintain effectiveness. All six bands showed

similar saline loss when bench-tested. CONCLUSION: Adjustable gastric

bands are semipermeable, leading to a small reduction in saline

volume

with time. Patients should be informed of this effect, attend for

regular follow-up visits and seek help if the band's effectiveness

appears reduced. We recommend that the volume present should be

checked

and readjusted at least every 6 months.

7/18/05

280/190/140