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Pasadena, CA 91105

Bowel Length Hess Calculator


Total Length (TL) cm:   

Alimentary channel length (AL) cm:   

Common channel (CC) cm:   

Dr. Ara Keshishian follows Dr. Douglas Hess’ procedure for calculating the limb lengths of Duodenal Switch. The following is Dr. Hess’ statement on measuring for Duodenal Switch limb lengths. Here is a blog post regarding Duodenal Switch limb lengths. Dr. Ara Keshishian discussing Duodenal Switch limb lengths in a video.

The proper measurements when performing the Biliopancreatic Diversion with the Duodenal Switch are very important for good long term results.  If the common channel is too long or the stomach is too large the patient may not have good sustained weight loss.  If the alimentary limb is too short the patient may not be able to absorb adequate protein and may require a revision. The patient must be able to eat, the duodenal stoma should not be small, but wide open, so the patient can take in protein.

We have measured the total small bowel length in more than 1400 patients we have operated and there is a large difference from the shortest (12 feet) to the longest bowel (38 feet).  You can see that one size does not fit all!  In our experience a common channel of 10% is the best size.  We use three sizes: 50 cm, 75 cm, and 100 cm whichever is the closest to the ten percent mark.  This way we have three sizes of  common channels and we can group them together to evaluate the lengths.  The length of the common channel determines the degree of malabsorption of fat.  You will, however, absorb enough fat for all the essential fatty acids needed for life.

The alimentary limb (the portion of small bowel which the food passes through) is formed nearest to 40% of  the lower part of the small bowel, always in increments of 25 cm (10 inches) from 250 to 350 cm as shown below.  The most common size used is 75 cm for the common channel and 275 cm for the alimentary limb.  For example: the common channel length is 100 cm in only 7% of our cases, 75 cm in  67  %,  and 50 cm in  23 %.  From this you can see we feel that using a 100 cm common channel is not correct in most cases.

We believe measuring the total bowel is very important for good long term results.