Brief Answer:
Indigestion overlapped with gut flora disturbance.

Detailed Answer:
Hi,
Thanks for query.
I've gone through all your details and I appreciate your concerns.

Two most common causes of increased bloating are-

Swallowing air while you eat or drink can cause air to collect in the digestive tract.

Second, as you digest food, digestive gases are formed as a result of fermentation and digestion of food which can also collect. Either method can cause bloating and belching.

The pathophysiology of gas is complicated. Understanding gut microflora, gas production, intestinal transit, intestinal propulsion of gas, and sensory function within the GI tract are essential for understanding symptom generation.

There is various mechanism that can be related to increased gas formation.

If this microflora is disturbed food is improperly fermented causing the production of a lot of gases in the gut leading to severe gases in the abdomen. These gases compress the intestines hence causing pain in abdomen and chest area, shortness of breath and bad odor from the body.

Hence most common cause in most of the cases is disturbed microbiota. In old patient mobility of intestines is severely compromised leading to accumulation of a lot of gases in intestines. As peristaltic moments are week gas accumulates in intestines.Severe constipation or incomplete evacuation can also hinder the passage of gases.


-Small Intestinal Bacterial Overgrowth can be a reason of severe bloating.
Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria are present in the small intestine, and the types of bacteria in the small intestine resemble more the bacteria of the colon than the small intestines causing improper and disturbed food digestion.


Suggestion-
Take Nexium 40 mg twice daily.
Proper food habits are essential to control excessive bloating.

Avoid-
Dairy products, which contain sugar lactose that causes gas.
Vegetables, including onions, radishes, cabbage, celery, carrots, brussel sprouts, broccoli, cauliflower, and legumes.

Fruit sugar, which is especially high in prunes, raisins, bananas, apples, apricots and fruit juices from prunes, grapes and apples
Fiber.
Fatty foods and carbonated drinks.

Eating more fermented foods. These are rich in both good bacteria and enzymes you can try raw natto kefir or cultured veggies. This is probably one of the most important first steps.
Taking a high-quality probiotic.

Exercising, to help keep food moving through your system.
Using spices that may help to prevent flatulence. These include turmeric, coriander, peppermint, fennel, sage, chamomile, and ginger.
Finally, when you reintroduce a food that was previously a gas-causing food, be sure you do so slowly. This will give your body a chance to adapt to the adjustment.


Tests suggested-
Small bowel imaging and a gastric-emptying scan.


Hope I answered your query with relevant details. I have included pathophysiological details also so that you can understand things better.

In case you need any other professional advice feel free to ask.
Thank you.

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