“…What is the length of my common channel” is probably one of the frequently asked questions about the duodenal switch operation in the office. This usually comes up at the initial consult when patients repost credible sources such as Dr. Google and Dr. Facebook for patient with different bowel length have done well or not so after duodenal switch operation. Dr. Hess described the Duodenal Switch by using total bowel length measurements and creating the common channel as a percentage of the total small bowel length. However, it seems that this is being done less and less.
This leads to my explanation that is on the website
Hess calculator : Bowel Length Calculator
How the actual measurements matters: Bowel length video link
In 2019, Bekheit et.al published a very interesting study comparing total small bowel length (TSBL) to a number of variables such as height, weight, sex and BMI. They identified a few loose correlations. Male patient have longer TBSL than females. There was correlation between TSBL and height stronger in males than females but not statistically significant.
In Conclusion they reported ” Despite statistical significance of the correlation between the TSBL and the height and weight of the included participants, the correlation seems to have no clinical meaning since the effect size is negligible. ”
As I have previously discussed this Making the common and alimentary length standard for every duodenal switch patient will make some loose too much and other not enough weight.
Figure 1 shows TSBL on the horizontal axis, and height, weight, BMI and Age on the vertical axis. For the most part what they all show is that one can not predict how long a patients bowel is by any of the measures that we take in the office as a part of the routine exam.
This raises, the concerns that I had raised previously. How could two similar patients who have the same weight, age, sex and BMI have the same surgery and expect the same result if one of them has TSBL of 400 cm and the other one 800cm?
If both of the patients get the same “cookie cutter” duodenal switch with the same lengths, then the patient with TSBL of 400 will have much longer common channel if the surgeon does not customize the length of the bowel. This is an example of many patients whom we have revised over the years where they had a duodenal switch done with the “standard” 125cm common channel and when we measured the total length the patient had 500 cm TSBL.
As I was looking over old archives, I came across the following pictures that were taken years ago. These were photographs taken to demonstrate the technique for the construction of the anastomosis of the biliopancreatic channel and alimentary channel of the Duodenal Switch.
The steps of doing the stapled anastomosis of the Duodenal Switch is generally unchanged during the laparoscopic approach to the procedure.
The stitches are placed to secure the bowel together. Two small openings are made in each limb of the bowel to be stapled together (the biliopancreatic limb on the bottom and the alimentary on the top of the image).
It is important to also align the bowel in the same peristalsis direction. This means that the contraction and the relaxation motion of the bowel should all point in the same direction. This should reduce the risk of complications such as intussusception.
When the stapler is fired in opposite direction, a very wide anastomosis is created.
Once the anastomosis is created, then the last staple is used to close the opening that was made. This staple line is perpendicular to the direction of the anastomosis to avoid making the opening narrow.
The FDA had initially approved almost all PPI’s, and antacids with an explicit limit placed on the duration of the therapy, which ranged in days to weeks. At that time there were no long term studies done on the health benefits, or side effects of the long term use of the PPI.
This Summary Letter outlines all the concerns dating back to 2011. I have found the information in this letter a good overview of the supporting medical evidence and lack of any long term data in regards to long term PPI.
The FDA made changes in the Black Box warning of the PPI medications. This was done with the mounting evidence and the health concerns of long term PPI use.
PPI’s have been shown to have detrimental long term side effects. It is prudent that a patient is continuously monitored and evaluated for identification of the possible underlying causes of the reflux, that may be the reason for the PPI use. There are a whole host of potential causes of reflux and other options for treatment.
There have been numerous studies recently published:
Protein intake requirements change over time following weight loss surgery. This is based on the requirements imposed on our body by a number of variables. These include, activity level, muscle mass, over all health condition to name a few.
A very young muscular athletic male with a BMI or 30 will require much higher protein intake (and absorption) that an inactive older Female with the same BMI. The same young athletic male will require much higher protein intake is he is recovering from a surgery than his baseline.
As we have stated in the past, the protein intake, should be adequate and not excessive. High level of protein intake that are not accounted for based on muscle mass and activity level, will eventually result in weight gain. The best measure of protein intake in a stable weight patient over 3-4 years post op is their albumin and protein level. Following your yearly laboratory values at a minimum is an important part of weight loss surgery follow up care.
You also need to adjust protein intake when necessary. Protein needs increase depending on physical needs, infection, healing, pregnancy, surgery, age, injury, etc. Plastic surgery requires higher protein needs for appropriate healing.
Information on protein sources and quality here.
The basic formula for protein intake is 1gm/kg of ideal body weight. The calculator below will provide a guide for the protein into based on your stable weight in lbs.
Obesity is related to as many as 400,000 deaths each year in the US and it has increasingly been recognized as a risk factor for several nutrient deficiencies. This may seem surprising given the likelihood of over consumption of calories, however these additional calories are not from nutritious sources. One of the main reason for these nutritional deficits is the greater availability of inexpensive foods that are rich in calories and are nutrient deficient. This has led some medical professional to conclude that there is a certain group of people who are overfed but undernourished. Even with the epidemic of the obesity, there is significant nutritional deficiencies noted.
Obese subjects have increased blood volume, cardiac output, adiposity, lean mass and organ size all of which can influence volume of distribution, in addition, treatment for severe obesity involving surgical procedures can worsen these nutrient deficiencies and in some cases may cause new ones to develop.
This table shows the percentage of population below the estimated average requirement (EAR) by body weight status in adults more tan 19 years old, showing that almost 90 to 100 percent of people including normal weight (NW) are below the EAR of vitamin D and Vitamin E.
Nutritional deficiencies in obese patients may promote the development of chronic diseases including increased insulin resistance, pancreatic B-cell disfunction and diabetes, this is because specific micronutrients are involved in glucose metabolic pathways; There are other chronic diseases related to obesity that are being investigated such as decrease in focal grey matter volume and cognitive impairment or inadequate sleep due to low intake of antioxidant vitamins.
We would like to thank Miguel Rosado, MD for his significant contribution provided for this Blog.