Oral Rehydration Therapy
Oral rehydration can be used to treat mild to moderate dehydration in a
stable patient. IV therapy is the first choice for severe dehydration,
moderate dehydration with continued losses, an unstable patient, or in
patient's with fluid loss of more than 10 mL/kg/hour. The regimen
is similar in concept to iv rehydration. The patient receives a rehydrating
solution containing deficit electrolytes, followed by a maintenance solution.
A keystone of oral rehydration therapy is slow, but steady oral intake;
this makes it a very labor intensive method.
In mild dehydration, administer 50 mL/kg of rehydrating solution over
the first four hours (about 2 mL per kilogram every ten minutes).
For moderate dehydration, give 100 mL/kg of rehydrating solution over 6
hours (almost 3 mL per kilogram every ten minutes). After this period,
give maintenance fluid at 100 mL/kg per day. The following table
gives the formulation of commonly available rehydration solutions:
Oral rehydration solutions (Adapted from Feld
& Jospe)
| |
Na mEq/L |
K mEq/L |
Cl mEq/L |
Base source |
Base mEq/L |
Carbohydrate |
% w/v |
| Rehydrating Solutions |
|
|
|
|
|
|
|
| Rehydralite |
75 |
20 |
65 |
Citrate |
30 |
Glucose |
2.5 |
| WHO formulation |
90 |
20 |
80 |
HCO3- |
30 |
Glucose |
2 |
| Baltimore City Hosp. Soln. |
50 |
20 |
40 |
HCO3- |
30 |
Glucose |
2 |
| Maintenance Fluids |
|
|
|
|
|
|
|
| Resol |
50 |
20 |
50 |
Citrate |
34 |
Glucose |
2 |
| Ricelyte |
50 |
25 |
45 |
Citrate |
34 |
Rice syrup solids |
3 |
| Pedialyte |
45 |
20 |
35 |
Citrate |
30 |
Glucose |
2.5 |
| Infalyte |
50 |
20 |
40 |
|
30 |
Glucose |
2 |
| Lytren |
50 |
25 |
45 |
|
30 |
Glucose |
2 |
The rehydration solution can be approximated by adding 8 tsp of table
sugar, 1/2 tsp of salt, 1/2 tsp of sodium bicarbonate (baking soda), and
1/3 tsp of potassium chloride to 1 L of water.
Note that milk products should be avoided after gastroenteritis because
of impaired lactase production resulting from sloughing of the apical brush
border cells. For infants with gastroenteritis and dehydration, there
is controvery about the benefit of gradually transitioning from an electrolyte
solution to formula (versus simply going to full-strength formula).
Part of the rationale behind the transitioning is that formula introduces
a greater electrolyte load, and therefore mandatory renal water excretion.
Clear fluids are not appropriate in oral rehydration. If only
rehydration solution is available, it can be used in conjunction with other
fluids low in sodium to dilute the sodium load to a maintenance level.
Fluids like soda, tea, and water are not appropriate for oral rehydration.
Some fluids are closer to the maintenance fluids, however, and can be part
of maintenance:
Electrolyte Composition of Common Beverages (adapted from Feld)
| Beverage |
Na mEq/L |
K mEq/L |
Cl mEq/L |
Base |
Carbohydrate (gm/100 mL) |
| Apple Juice |
0.46 |
27.03 |
? |
Citrate |
12.42 |
| Club Soda |
9.55 |
34.23 |
? |
Bicarbonate |
0 |
| Coca Cola |
1.75 |
trace |
26.83 |
Bicarbonate |
10.56 |
| Coffee (brewed) |
0.48 |
16.90 |
? |
Citrate |
0.3 |
| Gatorade |
22.60 |
2.49 |
17.0 |
Citrate |
4.44 |
| Ginger Ale |
3.67 |
0.36 |
? |
Bicarbonate |
8.2 |
| Grape Juice |
0.91 |
31.41 |
? |
Citrate |
17.5 |
| Hawaiian Punch |
9.17 |
6.82 |
? |
Citrate |
12.4 |
| Jell-O |
25.0 |
0.25 |
10 |
Citrate |
14.1 |
| Kool-Aid |
0.74 |
0.09 |
0 |
Citrate |
10.2 |
| Milk (whole) |
22.43 |
38.03 |
268.28 |
Lactate |
5.1 |
| Milk (2%) |
22.78 |
38.23 |
268.28 |
Lactate |
5.2 |
| Milk (skim) |
23.35 |
38.46 |
268.28 |
Lactate |
5.3 |
| Orange Juice |
0.48 |
53.90 |
0.83 |
Citrate |
11.8 |
| Tea |
1.61 |
6.80 |
tr |
Citrate |
10.3 |
Please direct all comments to: 
Last modification: April 30, 1998
