GSE
Gastroparesis (Delayed Stomach Emptying) - its physiology
Gastroparesis(Delayed Stomach Emptying)
What is gastroparesis?
Gastroparesis is a disease or
disorder of the muscles of the stomach or the nerves controlling these muscles
that causes them to stop working. This
results in the stomach taking too long to empty its contents into the intestine
and an inadequate grinding of food.
Who has gastroparesis?
More common in women. A hormonal link has also been suggested, as
gastroparesis symptoms tend to worsen the week before menstruation, when PROGESTERONE
levels are highest. Dysmotility can also affect men and children;
A study of 146 patients with gastroparesis.
Seen over the course of 6 years, patients
at a referral center
demonstrated that:
• 35%
had idiopathic gastroparesis. i.e. it "came out of the blue", and they didn't
know why!
• 30%
had diabetic gastroparesis;
• 13%
had gastroparesis related to surgical injury of the vagus nerve;
•
7.5% of cases were related to Parkinson's
disease or other neurologic conditions;
• 4.5%
were related to intestinal pseudo-obstruction;
•
Remaining 10% of cases included other miscellaneous conditions. Specifically
connective tissue diseases, such as scleroderma.
Soykan I, Sivri B, Sarosiek I, et al.
Demography, clinical characteristics, psychological abuse profiles, treatment,
and long-term follow-up of patients with gastro paresis. Dig Dis Sci.
1998;43:2398-2404.
Physiology of gastroparesis
Normal Food path from stomach to small intestine. The stomach
is a muscular sac about the size of a small melon, that expands when you eat or
drink to hold as much as a gallon of food or liquid. The stomach mechanically
churns and pulverizes your food while hydrochloric acid (HCl) and enzymes
requiring an acid environment break it down. Muscle fibers of the stomach wall
create structural elasticity and contractibility, both of which are needed for
digestion and propelling food towards the intestines.
Pyloric Sphincter/Valve controls release of food
from the stomach
- The pyloric sphincter (valve between stomach and intestines)
stays closed while food is being digested in the stomach
(to
keep the food inside the stomach). During digestion, strong muscular contractions
(peristaltic waves) push the food toward the pyloric valve, which is the gateway
to the upper portion of your small intestine (duodenum);
- When HCl and the stomach
enzymes have had enough time to do their job, alkaline bile
(from gall bladder)
and pancreatic juices
(a watery bicarbonate solution) are secreted into the
upper small intestine
(duodenum). This prevents damage to the duodenum when the stomach's highly acidic
contents are released;
- Once the duodenum has
become strongly alkaline, the pyloric sphincter receives a signal to open, and
the partially digested food is released into the small intestines.
This is where
most of the absorption of nutrients takes place.
•
Chronic dehydration will prevent pyloric valve
from opening. there is an insufficient
water supply in the body's circulation from which the pancreas can produce the
watery bicarbonate solution required to protect intestinal lining from stomach's
acidic contents
