Ewald and Boas1 have studied the normal condition of gastric secretion in man. According to their observations, as soon as food enters the stomach, this organ begins to secrete its specific juice and continues to do so until the food has passed into the intestine. During the last period, however, the secretion is but very slight. That is the reason why examinations of the gastric contents reveal different results if made at various periods after partaking of food. In order to be able to judge in an exact manner whether the gas-trie secretion is normal or not, we must always make the examination under equal conditions, that is, after a certain meal. Several test meals have been proposed for this purpose.

Fig. 11. - Transilluminated Zone of the Stomach in Gastroptosia (from Mrs. P. F.).

1 Ewald and Boas: Virchow's Archiv, vol. 101, p. 325.

Fig. 12. - Result of Gastrodiaphany in a Patient with Carcinoma of Stomach. Dark area represents situation of tumor.

1. Leube-Riegel's Test Dinner

The oldest form of test meal is the test dinner of Leube and Riegel. This consists of a large plate of soup (about 400 c.c.), a large portion of meat (beefsteak or something of that kind), some potatoes, and a roll. The time for examination is about three to four hours after the partaking of this meal.

2. The Test Breakfast Of Ewald And Boas

This is taken in the morning in a fasting condition and consists of one to two rolls (35-70 gm.) and one cup of tea or water (300-400 c.c). Time for examination, about one hour after the meal.

3. Germain See's Test Meal

This consists of 60-80 gm. of scraped meat and 100-150 gm. of white bread. Examination takes place two hours after the ingestion of the food.

4. Klemperer's Test Meal

This consists of one pint of milk and two rolls. Examination takes place two hours afterward.

The two test meals that are mostly in use are the Leube-Riegel's test dinner and Ewald-Boas' test breakfast. In 1888 I1 made a comparative study of the results obtained three to four hours after the test dinner, and those derived in the same cases one hour after Ewald's test breakfast. In some persons I was able to find free hydrochloric acid after the test breakfast, but not after the test dinner. Besides, the degree of acidity was more constant in the same individual after the test breakfast than after the dinner. Moreover, we are able to recognize some remnants of food from the previous day much more easily after the test breakfast than after the test dinner. As the test breakfast consists only of water and rolls, any other particles of food found in the gastric contents, as for instance meat, asparagus, would indicate that these substances have been left there from a previous meal. The test dinner being quite a complicated meal, does not allow us to recognize this so clearly, and it is necessary to examine the patient again in a fasting condition in case there is suspicion that the motor function of the stomach is impaired.

These advantages have also been recognized by other authors, and nowadays almost all agree in preferring the test breakfast to the other test meals.

1Max Einhorn: "Proberaittagbrod oder Probefruhstuck." Berl. klin. Wochenschr., 1888, No. 32.

The stomach contents may be obtained for purpose of examination by the following methods:

By means of the soft-rubber tube and either aspiration or expression. In using the tube it is best to have one with several openings at the lower end and to attach a small glass tube about three to five inches in length to the upper end (see Fig. 13). The tube is first immersed in a pitcher of warm water. The patient is provided with a bib or towel around his neck and sits on a chair, holding a wide-mouthed bottle in his left hand, near his chest; the physician takes the tube from the pitcher, places the glass end piece into the bottle, tells the patient to open his mouth, and inserts the tube, pushing it forward into the pharynx. (The physician need not insert his finger into the mouth of the patient.) The patient is now told to swallow once or twice, and the tube is rapidly pushed with thy right baud into the stomach (about 44-4;. cm.).

In using aspiration, one can either attach a Politzer bulb over the glass piece (Ewald) or Boas' aspirator, which consists of a rubber bulb having two soft-rubber ends provided with a clamp (see Fig. 14). The bulb is first compressed and then released, and in this way aspiration is secured and the bulb fills itself with the gastric contents.

Fig. 14. -Boes' Aspirator.

Ewald-Boas' Expression Method

The expression method consists in having the patient exert pressure upon his stomach by means of his abdominal muscles. This is best done by telling the patient first to inspire deeply and then to compress his abdominal walls in the same manner as during defecation. The pressure exerted in this way upon the gastric contents expels them through the tube into the bottle. This expression method is now almost exclusively practised everywhere. It is the easiest and best way of obtaining the gastric contents.

Fig. 14. - Boas' Aspirator.

Before removing the tube, it is necessary to occlude the glass opening with a finger of the right hand and to withdraw the instrument quickly from the stomach. (By closing the opening we avoid the return of some of the food particles contained within the tube into the oesophagus or pharynx; the tube is then emptied into the bottle containing the stomach contents).

The ingesta obtained in the above-described way one to one and a half hours after the test breakfast are then filtered, and the filtrate is subjected to the following tests: 1. Reaction. 2. Hydrochloric acid. 3. Lactic acid. 4. Acidity. 5. Propeptone. 6. Peptone. 7. Pepsin. 8. Rennet ferment. 9. Dextrin. 10. Erythrodextrin. 11. Achroodextrin. 12. Maltose.