An important aid in bringing out the contours of the stomach is the artificial distension of the organ by the generation within it of carbonic acid gas, as first suggested by Frerichs. For this purpose 20-30 grains of bicarbonate of sodium and 15-20 grains of tartaric acid, each dissolved in a little lukewarm water, may be given one after the other. If the stomach be much dilated and relaxed, it may be necessary to give much larger quantities of the powders (up to 2-2½ drachms of the soda and a corresponding quantity of the acid). It is well to have a stomach-tube at hand in order to withdraw the gas in case unpleasant symptoms develop. Sometimes the stomach fails to become distended by this procedure. This is due in some cases to the escape of the gas through the pyloric orifice into the intestine—a condition designated by Ebstein as incontinence of the pylorus. It may be that sometimes the gas produces such firm contraction of the gastric walls that the stomach does not expand by the pressure of the gas. Instead of generating gas, a similar result may be produced by simply injecting air into the stomach through a stomach-tube, as recommended by Oser and by Runeberg. The air may, however, escape along the side of the tube.
Palpation of the distended stomach yields an elastic resistance which has been compared to that of an air-cushion. By palpating carefully from above downward the greater curvature can sometimes be appreciated, but in general it is difficult to distinguish it from the transverse colon. Peristaltic movements may perhaps be appreciated by palpation when they are not evident on inspection. If a dilated stomach contains considerable fluid and the abdominal walls are yielding, fluctuation may be perceived by palpation. The lowest level at which this fluctuation can be felt may afford a clue as to the position of the lower border of the stomach, but not much dependence can be placed upon this sense of fluctuation unless many sources of error in its interpretation are excluded.
By pressing gently and repeatedly against the abdominal walls a splashing sound can usually be heard in cases of well-marked dilatation of the stomach (bruit de clapotement). This sound can best be brought out when the patient is in the recumbent position, with relaxed abdominal walls, by palpating near the left border of the ribs. The same sound can be produced by shaking the patient (bruit de glou-glou). This sound may be heard at a considerable distance from the patient, to whom it may be a source of much annoyance. In itself this splashing sound is without diagnostic significance, as the condition for its production—namely, the simultaneous presence of gas and liquid in the stomach—exists often in healthy persons. By paying attention, however, to the time at which this sound can be produced after eating or drinking, and to its greater or less constancy, some diagnostic importance can be attached to this sign. If the splashing sound can be usually produced two hours or longer after the ingestion of liquid or six hours after an ordinary meal, it generally indicates that dilatation of the stomach exists.17 It is necessary to exclude somewhat similar sounds which may be produced in the intestines, particularly in the transverse colon and cæcum. The series of gurgling sounds which may sometimes be produced in the intestine by palpation are not likely to be confounded with the single splashing sound produced in the stomach, but under certain circumstances a splashing sound may be produced in the transverse colon which cannot be distinguished from the gastric sound. If a dilated stomach contains a very large quantity of fluid, the splashing sound cannot readily be produced.
17 Baradat, Étude sur le Bruit de Clapotement stomacal, Thèse, Paris, 1884. Baradat says that this bruit is also diagnostic of dilatation when it can be produced by palpating below a horizontal line passing through the junction of the ninth and tenth ribs, but it is evident that motion might be transmitted to the stomach even when its greater curvature is above this line by palpating below the level of the umbilicus.
Leube has pointed out that the end of the stomach-tube (of course the hard tube), after it has been inserted into the stomach, can often be felt through the abdominal walls.18 He says that if the tube can be felt below a horizontal line passing through the anterior superior spinous processes of the ileum, dilatation of the stomach may be positively diagnosed, and the existence of dilatation is probable if the tube can be felt much below the umbilicus. No force should be used in trying to make the end of the tube palpable. Of course if the abdominal walls are thick or very tense the tube cannot be felt. Leube's method is simple and convenient, and applicable to many cases. As will be explained hereafter, a position of the lower border of the stomach even quite as low as Leube's rule demands cannot be considered by itself positive evidence of dilatation.19
18 Deutsches Arch. f. kl. Med., Bd. xv. p. 394.
19 According to Oser, there is a possible source of error in Leube's method—namely, that the sound may slide along the greater curvature of the stomach, and even reach the pylorus, so that the end may be felt higher than the lowest point of the stomach. Considerable objection has been made to Leube's method on the ground of its danger, but this objection is based on the assumption that greater energy is employed in pressing forward the sound than Leube recommends (Oser, article "Magenerweiterung" in Eulenburg's Real Encyclopädie, Bd. viii., 1881).
The length to which the stomach-tube can be inserted before meeting resistance may evidently give some idea as to the size of the stomach. The attempt, however, to establish any general law with reference to this point has not proven successful.
In many cases valuable information as to the size of the stomach is afforded by percussion. Over the greater part of the stomach the percussion note is tympanitic, sometimes with a metallic quality. Over the most dependent part of the stomach a dull sound is produced on percussion in case a sufficient quantity of fluid or solid material is contained in the viscus. In the upright position, therefore, in percussing over the stomach from above downward, the tympanitic note gives place to a dull sound, and this zone of dulness will change with the position of the patient, so that in the recumbent posture the dulness may entirely disappear. In order to prove that the region of dulness belongs to the stomach, Piorry caused the patient to drink a large quantity of water (a pint to a quart). In a healthy empty stomach this quantity of water suffices to produce a zone of dulness which does not descend below the level of the umbilicus. If, however, the dulness be produced below the level of the umbilicus, it is inferred that dilatation exists. Penzoldt's modification of Piorry's method gives more certain results.20 By withdrawing the fluid from the stomach by the stomach-tube the dulness may be made to disappear, and by injecting more fluid the dulness may be made to reappear at will. By noting the lower limit of the dulness thus produced the position of the lower border of the stomach may be determined. The farther this lies below the umbilicus the greater, presumptively, is the degree of dilatation. The artificial distension of the stomach with gas may also aid in determining its limits by percussion. It must be said that in general the separation of the lower limits of the stomach from the transverse colon by means of percussion is a matter of great difficulty, and sometimes is impossible.
20 Penzoldt, op. cit., p. 48.