PAPERS ON MEDICINE AND PUBLIC HEALTH 269 



tions, the diameter of each being equivalent to the maxi- 

 mum bore of the tubing. The principle of the tube is en- 

 tirely that of gravity, and the tip is sufficiently heavy to 

 seek the lowest portion of the stomach. The instiniment is 

 inserted and left in the stomach for hours until the gastric 

 cycle is completed. It is possible at any given moment to 

 draw off any or all of the juice secreted in sufficient quan- 

 tity to perform the necessary chemical examination. 



METHOD 



The patient is requested to drink no water at any time 

 after the evening meal on the night pre\ious to examina- 

 tion, and to eat nothing until after the test is complete. 

 Usually he presents himself about 8 o'clock the following 

 morning for removal of residium by means of the Rehfuss 

 tube. 



REMOVAL OF RESEDIUM 



The swallowing of the tube may be accomplished with- 

 out the aid of water. In obstinate cases where swallow- 

 ing is difficult the process may be accomplished by coating 

 the tube and tip with a thin film of petrolatum, and by 

 placing the tip in the lower part of the pharjTix, back of 

 the tongue, and having the patient swallow. When the 

 tube has reached the stomach (which has been determined 

 by measurement) the contents are aspirated. A nonnal 

 residium of large volume possessing a total acidity value 

 of seventy or over may indicate ulcer. 



THE TEST MEAL 



Before making an analysis of stomach contents it is 

 customan.- to introduce something into the stomach which 

 will stimulate the gastric cells. The response to this stimu- 

 lation is then measured clinically by the deteraiination 

 of total and free acidity in the stomach contents. The 

 test meal most widely employed is the Ewald test meal, 

 which consists of 2 pieces (35 grams) of toast and 8 

 ounces of tea or water. (The water meal is ad\ised because 

 it has the added advantage of enabling one to determine 

 the presence of food rests, and to test more accurately for 

 blood and bile.) 



