There is some evidence in the literature of contractions of the esophagus synchronous with the periods of gastric hunger contractions. Some people refer the hunger sensation or hunger pangs, not only to the stomach, but also to the chest and throat. This appears to be true, not only of ignorant people, such as those interrogated by Schiff, but also of persons of special training in introspection. Cannon and Washburn have described periodic contractions of the lower end of the esophagus in man, and these contractions seemed to give rise to hunger pangs just as in the case of the contractions of the empty stomach. They suggest that the esophagus contractions are synchronous with the gastric hunger contractions, but they did not prove the hypothesis by recording the stomach and esophagus contractions simultaneously.
We studied the motor conditions of the esophagus in hunger on three men who experienced no difficulty in swallowing simultaneously the gastric and the esophageal balloons with their flexible rubber tube attachments. In part of the work we used the best quality of rubber condums also for the esophagus balloon, not in their entire length, as in the case of the stomach, but cut down to a length of 3 to 4 cm. We soon encountered difficulties in the work with the esophagus, difficulties apparently not noticed by Cannon and Washburn. Thinking that part of these difficulties might be due to the diameter of the esophagus balloon, we resorted to the rubber finger cot employed by these observers. But even the best rubber finger cots are not as satisfactory as the condum balloon.
The position of the balloon in the esophagus was usually determined by the distance from the incisor teeth to the lower end of the balloon. If the balloon is clear above the cardia the movements of inspiration decrease the positive pressure in the distended balloon in proportion to increase in the negative pressure in the thoracic cavity. But if the balloon is located in the region of the cardia itself, it depends on the relative preponderance of diaphragm and chest movements whether the act of inspiration leads to increase or decrease in the balloon pressure. The esophagus balloon can be well in the cardia and still show negative pressure in inspiration if the inspiration is predominantly costal. On the other hand, if the lower end of the balloon is just within or at the cardiac orifice, a diaphragmatic inspiration increases the pressure in the balloon, although not to the same extent as when the balloon is in the fundus of the stomach.
In the case of A. J. C. and J. H. L. it was found that when the distance from the lower end of the esophagus balloon to the incisor teeth was 15 1/2 to 16 inches the balloon was as far down as it could be located without being directly affected with the contractions of the cardia and the stomach. Allowing the balloon to slip down 1/2 to 1 inch farther brought it to the cardia and the cardiac end of the stomach. In the case of A. B. L. the distance from the incisor teeth to the lower end of the balloon could not exceed 14 1/2 to 15 inches, if pure esophagus effects were to be obtained. When the esophagus balloon is located 14 to 16 inches from the incisor teeth, it is obviously well below the level of the heart, and therefore in the region of myenteric plexus and non-striated musculature of the esophagus.
The esophageal and stomach tubes were usually joined together firmly, so that the lower end of the esophagus balloon was i 1/2 inches above the upper end of the stomach balloon. The pressure in the esophagus balloon varied between 1 and 4 cm. of chloroform.