Chart Used in Johns Hopkins Hospital.—The following chart is inserted here to show the method used in the Johns Hopkins Hospital for carrying out the Two-hour Renal Test:
| Time of Day | Urine | NaCl | Nitrogen | |||
| C.C. | Specific Gravity | Per cent | Grams | Per cent | Grams | |
| 8 A.M.-10 A.M. | ||||||
| 10 A.M.-12 Noon | ||||||
| 12 Noon-2 P.M. | ||||||
| 2 P.M.-4 P.M. | ||||||
| 4 P.M.-6 P.M. | ||||||
| 6 P.M.-8 P.M. | ||||||
| 8 P.M.-8 A.M. | ||||||
| Total day | ||||||
| Night, 8 P.M. to 8 A.M. | ||||||
| Total 24 hours | ||||||
| Intake of fluid | ||||||
| NaCl | ||||||
Urine to be collected punctually every two hours and kept in the ice-box, every specimen having twenty drops of tutuol added to insure preservation.
Another modification of the Hedinger-Schlayer diet is used in the Peter Bent Brigham Hospital,[131] Boston, Massachusetts, as follows:
| 7 A.M. | Coffee, milk, sugar, toast, and butter. |
| 10 A.M. | Milk, toast, and butter. |
| 12:30 P.M. | Bouillon, broiled steak, butter, mashed potatoes, toast, coffee, milk, sugar. |
| 4 P.M. | Tea, milk, sugar, crackers. |
| 7 P.M. | Soft egg, blanc-mange (1 egg, sugar, cornstarch, and milk) and cream. Amounts sufficient to give 2500 calories, 1500 c.c. fluid, 76 grams of protein, 127 grams of fat, 245 grams of carbohydrate, and from 5 to 8 grams of sodium chloride. |
On two days previous to the test the patient usually had a diet containing 2000 calories, 75 grams of protein, 4 grams of sodium chloride.
The test diet is a mixed diet containing known amounts of water, nitrogen, and chloride, together with the food diuretics (purins, salt, and water), as can be seen. The diet is divided into unequal portions containing known but varying amounts of fluid, nitrogen, and salt. Two-hour specimens are collected from 7 A.M. to 9 P.M., and one night specimen is obtained containing all the urine passed between 9 P.M. and 7 A.M. Each specimen is analyzed for volume, specific gravity, total nitrogen, nitrogen concentration, total chloride, and chloride concentration.
Purpose of Tests.—The purpose of the test is to find out to what extent and in what manner the diseased kidney under stimulation by the various diuretics taken in the food reacts in putting out the varying amounts of salt.
Dr. O’Hara likewise describes another test known as The Added Urea and Salt Test, which was first described by von Monakow and also carried out in the Peter Bent Brigham Hospital. The method used was as follows: