Effects of Nasogastric Tubes on Swallowing: Frequency of Swallowing, Residue and Back Flow of Bolus

Abstract

The purpose of this study was to determine whether or not nasogastric (NG) tubes affect swallowing. Fifteen healthy adults were recruited into this study. We evaluated swallowing by using a videofluorography (VF) to examine the anterior-posterior plane. Subjects were administered 5 ml of 50% barium solution, 5 g of gelatin jelly and 5 g of agar jelly in that order. We compared the results between swallowing without a tube and swallowing with an 8 French or 14 French tube. Subjective symptoms during swallowing with a tube were evaluated using a numerical rating scale. All NG tube subjects complained of discomfort when swallowing and difficulty swallowing. The frequency of swallowing increased with the size of the tube. In some subjects, foods remained around the tube and back flow of food was seen along the tube. This study showed that swallowing was affected by NG tubes. The influence was greater the larger was the tube. Although subjects in this study were healthy adults without swallowing disorders, it is possible that patients with swallowing disorders will have a higher risk of aspiration. Oral intake without a NG tube is therefore recommended for patients with swallowing disorders.