Mechanism:
(1) The stomach becomes incontinent following a disruption of the normal pyloric sphincter or a resection of gastric wall with reduction in volume. It is more common after a Billroth II operation than a Billroth I.
(2) This allows the passage of a large bolus of food with a high osmolarity into the small intestine.
(3) Fluid enters the bowel to dilute the contents, causing intestinal distension and an autonomic response. There may be a sudden drop of intravascular blood volume.
(4) The presence of hyperosmolar contents in the distal small bowel results in the release of humoral factors such as enteroglucagon, neurotensin, vasoactive intestinal peptide, serotonin and bradykinin.
(5) There is a marked increase in gut motility to pass the load.
Onset: 20-30 minutes after a meal
Clinical findings:
(1) feeling of upper abdominal distension or fullness that starts shortly after a meal
(2) drowsiness, weakness and/or lassitude
(3) nausea
(4) eructations
(5) abdominal pain
(6) occasionally a patient may have bilious vomiting (bile unmixed with food)
(7) cold sweat or flushing of head and neck
(8) palpitations or tachycardia
(9) fainting or dizziness
(10) blurred vision
(11) flatulence
(12) intestinal borborygmi
(13) explosive attack of watery diarrhea
The type of meal can affect the severity of the reaction:
(1) The dumping may be triggered by a very hot or very cold food.
(2) Typically the triggering food is "heavy" or rich in sugar.
(3) An episode is more likely after a large meal rather than a small meal.
If the diagnosis is in doubt, symptoms can often be precipitated by drinking 200 mL of 50% glucose solution.
Differential diagnosis:
(1) White Castle hamburgers
(2) food poisoning (unlikely to be a recurrent problem)
