BMI

If you have acid reflux, chances are you are also obese or, at least, overweight. Many of our patients who are candidates for bariatric surgery have symptoms of acid reflux– heartburn, water brash (a sudden flooding of the mouth with saliva because of reflux of gastric contents into the food pipe), eructations, etc.

While a detailed discussion on the why’s and how’s of acid reflux are outside our syllabus in today’s class, it is important to just get an idea of the basic reasons why gastric acid gets up (against the tide) into the food pipe (esophagus).

The normal junction between the esophagus and the stomach is marked by a whorl of muscle fibers of the two organs that functionally works as a valve. This valve, called the LES (Lower Esophageal Sphincter) allows food to pass from the food pipe into the stomach, but not the other way. If it weren’t for this, we would keep burping up food into the mouth like infants. Now that wouldn’t impress our girl friends, would it?

(diagrammatic representation of the area of our interest. Pic source: www.chw.org)

In certain circumstances, the function of the LES is impaired, and the net result in the reverse entry of gastric acid into the food pipe (a place that is not adapted to acid pH). This happens if you eat too much, or oily/spicy/processed food, drink too much coffee or alcohol, or if you smoke. I am not even scratching the surface here.

In cases where the pressure within the abdomen is very high (as in advanced pregnancy or severe obesity) the excess pressure on the stomach overcomes the resistance of the lower esophageal sphincter and causes reflux. The food pipe gets inflamed as a result of the acid attack (reflux esophagitis).

In many instances there is a condition called hiatus hernia that causes severe reflux. This condition occurs when the junction between the food pipe and the stomach slides up into the chest cavity, as a result of which the positive intra-abdominal pressure pushes up the acid from the stomach into the esophagus, which is located in a negative (low) pressure zone inside the chest cavity.

With this background, we need to understand that most obese patients, specially those being considered for bariatric surgery, are chronic sufferers of reflux. However, it is important to understand that many upper abdominal or digestive symptoms (like pain after eating, vomiting, “gas”, for example) are due to associated gallstone disease.

Obviously, each of this is deserving of treatment on its own merit.

When we see patients, we evaluate the patient’s symptoms and consider reflux as a clinical diagnosis. The diagnosis is documented by other studies like upper GI endoscopy, barium study and esophageal manometry.

An ultrasound is always done to exclude gallstone diseases and to see the state of the liver. Fatty liver is almost always a given in the bariatric patient before surgery.

Now that we know what reflux is, how it occurs in the obese patient and how we detect it, we need to know what to do about it.

That will be Part Two.