Gastroesophageal reflux during gastrostomy feeding.

Abstract

To investigate the pathophysiology of aspiration pneumonia in patients fed via gastrostomy tube, the authors measured lower esophageal sphincter pressure in 10 patients1 before and 24 hours after percutaneous endoscopic gastrostomy tube placement and also during bolus vs continuous feeding.2 In five of these patients, gastroesophageal reflux scintigrams were obtained (using technetium‐99‐labeled feeding) comparing bolus and continuous feeding. Bolus feeding consisted of 250 mL of Jevity, an isotonic formula (310 mOsm/kg), followed by 100 mL of water, all given within 20 seconds; continuous feeding consisted of the same formula infused at 80 mL/h without added water. Lower esophageal sphincter pressure was measured continuously during the 15 minutes immediately after a feeding bolus and for another 15 minutes after initiation of continuous feeding 2 hours later. The scintigrams were obtained every 10 seconds during similar 15‐minute periods. Basal lower esophageal sphincter pressure was not affected by percutaneous endoscopic gastrostomy tube placement or by continuous intragastric feeding. In contrast, bolus feeding was associated with marked relaxation of the lower esophageal sphincter to incompetent levels (16.6 ± 4.6 mm Hg to 2.1 ± 2.0 mm Hg, p <.001). The scintigrams revealed gastroesophageal reflux to the sternal notch after bolus infusion but not during continuous feeding. The authors concluded that gastroesophageal reflux associated with lower esophageal sphincter relaxation occurs in response to bolus feeding but not in response to continuous feeding, presumably a result of gastric distention by the bolus. Continuous feeding is therefore recommended for reducing the risk of aspiration pneumonia.