In a number of diseases of the alimentary canal the administration of food by the natural channel is either impossible or inadvisable, and the physician must have recourse to methods of artificial nourishment. The entrance of food into the stomach may be prevented from mechanical causes, changes in the mouth, e.g. excessive thickening of the tongue or of the gums the result of inflammatory changes or tumour growth, obstruction of the oesophagus either from the pressure of a tumour or from organic changes in the gullet itself, most frequently from carcinoma, or it may be from diverticulum, spasm, or the presence of a foreign body. Again, though there may be no obstruction, the act of swallowing may be so inefficiently carried out through muscular paralysis that some form of artificial nourishment becomes a necessity if nutrition is to be maintained. In certain acute diseases of the stomach the physician desires to secure the diseased organ a period of physiological rest for recovery and repair, and it is sought during this period to maintain general nutrition by means of artificial alimentation.
Artificial feeding may be carried out by the rectum, subcu-taneously, or by means of the stomach tube.