1) Intravenous fluid therapy is used to treat fluid imbalances and electrolyte abnormalities. It involves determining the appropriate rate and type of intravenous fluid based on a patient's volume status, electrolyte levels, and ongoing losses or gains.
2) Common types of intravenous fluids include crystalloids like normal saline and lactated Ringer's, which are used for volume expansion, and colloids, which increase vascular volume more rapidly but are more expensive.
3) Maintenance intravenous fluids are given to replace normal daily losses when a patient cannot take fluids orally, while replacement fluids are used to correct existing dehydration or volume deficits based on parameters like blood pressure, jugular pressure, and urine output.