Intravenous (IV) rehydration is a treatment for fluid loss in which a sterile water solution containing small amounts of salt or sugar is injected into the patient's bloodstream.
Rehydration is usually performed to treat the symptoms associated with dehydration, or excessive loss of body water. Fever, vomiting, and diarrhea can cause a person to become dehydrated fairly quickly. Infants and children are especially vulnerable to dehydration. Patients can become dehydrated due to an illness, surgery, metabolic disorder, hot weather, or accident. Athletes who have overexerted themselves may also require rehydration with IV fluids. An IV for rehydration can be used for several hours to several days, and is generally used if a patient is unable to keep down oral fluids due to excessive vomiting.
A basic IV rehydration solution consists of sterile water with small amounts of sodium chloride (NaCl; salt) and dextrose (sugar) added. It is supplied in bottles or thick plastic bags that can hang on a pole or rolling stand mounted next to a patient's bed. Additional electrolytes (i.e., potassium, calcium, bicarbonate, phosphate, magnesium, chloride), vitamins, or drugs can be added as needed either in a separate minibag or via an injection into the intravenous line.
Signs and symptoms of dehydration include:
In infants, dehydration may also be indicated by a sunken fontanelle (the soft spot on the head).
A doctor orders the IV solution and any additional nutrients or drugs to be added to it. The doctor also specifies the rate at which the IV will be infused. The intravenous solutions are prepared under the supervision of a pharmacist using sanitary techniques that prevent bacterial contamination. Just like a prescription, the IV is clearly labeled to show its contents and the amounts of any additives. A nurse will examine the patient's arm to find a suitable vein for insertion of the intravenous line. Once the vein is located, the skin around the area is cleaned and disinfected. The needle is inserted and is taped to the skin to prevent it from moving out of the vein.
Patients receiving IV therapy must be monitored to ensure that the IV solutions are providing the correct amounts of fluids and minerals needed. People with kidney and heart disease are at increased risk for overhydration, so they must be carefully monitored when receiving IV therapy.
Patients must be able to take (and keep down) fluids by mouth before an IV rehydration solution is discontinued. After the needle is removed, the insertion site should be inspected for any signs of bleeding or infection.
As with any invasive procedure, there is a small risk of infection or bruising at the injection site. It is possible that the IV solution may not provide all of the nutrients needed, leading to a deficiency or an imbalance. If the needle becomes dislodged, the solution may flow into tissues around the injection site rather than into the vein, resulting in swelling.
According to the United Nations Children's Fund (UNICEF), over two million children die of diarrhea-related dehydration each year. Eighty percent of these children were two years of age or younger. In the United States, an estimated 300 people (children and adults) die of dehydration annually.
For patients who are able to tolerate fluids by mouth, oral rehydration therapy (ORT) with oral rehydration salts (ORS) in solution is the preferred treatment alternative. Another technique in which fluid replacement is injected subcutaneously (under the skin into tissues) rather than into a vein is called hypodermoclysis. Hypodermoclysis is easier to administer than IV therapy, especially in the home setting. It may be used to treat mild to moderate dehydration in patients who are unable to take in adequate fluids by mouth and who prefer to be treated at home (geriatric or terminally ill patients).
Hankins, Judy, et al., eds. Infusion Therapy in Clinical Practice . 2nd ed. Philadelphia: WB Saunders, 2001.
Otto, Shirlie. Pocket Guide to Intravenous Therapy . 4th ed. St. Louis: Mosby Inc., 2001.
Suhayda, Rosemarie, and Jane C. Walton. "Preventing and Managing Dehydration." MedSurg Nursing 11 (December 2002): 267-278.
Rehydration Project. P. O. Box 1, Samara, 5235, Costa Rica. (506) 656-0504. http://www.rehydrate.org .
Altha Roberts Edgren
Intravenous rehydration is typically prescribed by a doctor and administered by a nurse, physician's assistant, or home health care aide. It may be performed in a hospital setting, an ambulatory care center, or a home care setting.