Final answer:
The maximum fluid for an intradermal injection is 0.1 ml. IV therapy administers fluids like normal saline to dehydrated patients. The IV bag height for administration depends on blood pressure, with 1.61 meters being an example height to overcome 18 mm Hg blood pressure.
Step-by-step explanation:
The maximum amount of fluid that can be administered through an intradermal injection is typically up to 0.1 ml (milliliters). Intradermal injections are usually given for skin testing, such as tuberculin or allergy tests, and the small volume is necessary to create a small bubble under the skin, which can be assessed for reactions.
Intravenous therapy (IV) is commonly used to administer fluids to a dehydrated patient. The type of fluid given usually includes normal saline, which is a sterile solution of sodium chloride in water, the specific gravity of which is approximately 1.00 g/ml. This solution helps to replenish electrolyte balance and rehydrate the patient.
For an IV administration, one might need to calculate the appropriate height at which an IV bag should be placed so that the fluid pressure is slightly higher than the blood pressure in the vein—ensuring proper fluid flow. In a specific example, if the blood pressure in the vein is 18 mm Hg, and remembering that 1.0 mm Hg equals 133 Pascal (Pa) in SI units, one would find the necessary height for the IV bag. For instance, a saline solution surface might need to be placed around 1.61 meters above the needle entry point to achieve the necessary pressure, assuming no significant pressure drop in the tubing.