Alginate rafts (polysaccharide polymers that precipitate into a low-density viscous gel when they contact gastric acid) have been reported to form at the acid pocket, an unbuffered pool of acid that floats on top of ingested food and causes postprandial acid reflux.
Dr Guy Boeckxstaens and colleagues from Belgium studied the location of an alginate formulation in relation to the acid pocket and the corresponding effects on reflux parameters and acid pocket positioning in patients with gastroesophageal reflux disease (GERD).
The researchers randomly assigned patients with symptomatic GERD and large hiatal hernias to groups who were given either 111In-labeled alginate-antacid or antacid after a standard meal.
The relative positions of labeled alginate and acid pocket were analyzed for 2 hours by using scintigraphy.
Reflux episodes were detected by using high-resolution manometry and pH-impedance monitoring.
|The acid pocket was located below the diaphragm in 71% given alginate-antacid |
|Clinical Gastroenterology & Hepatology|
The research team found that the alginate-antacid label localized to the acid pocket.
The number of acid reflux episodes was significantly reduced in patients receiving alginate-antacid compared with those receiving antacid.
The team noted that time to acid reflux was significantly increased in patients receiving alginate-antacid vs those receiving antacid.
The researchers found that the acid pocket was located below the diaphragm in 71% of patients given alginate-antacid vs 21% of those given antacid.
There was an inverse correlation between a subdiaphragm position of the acid pocket and acid reflux.
Dr Boeckxstaens' team concludes, "In a study of 16 patients with GERD, we observed that the alginate-antacid raft localizes to the postprandial acid pocket and displaces it below the diaphragm to reduce postprandial acid reflux."
"These findings indicate the importance of the acid pocket in GERD pathogenesis and establish alginate-antacid as an appropriate therapy for postprandial acid reflux."