What condition is characterized by more than the normal total volume of blood in the body?

Plethora is the correct term for a condition characterized by an increased total volume of blood in the body. This condition often results in a reddened appearance of the skin as the excess blood causes dilation of blood vessels. Plethora can occur due to various physiological changes or as a result of certain diseases, such as polycythemia vera, where there is an overproduction of red blood cells leading to increased blood viscosity and volume.

In contrast, hyperemia refers to an increased blood flow to a particular area of the body, which is primarily a localized response often associated with inflammation or increased metabolic activity in tissues. Edema signifies an accumulation of fluid in the interstitial spaces, leading to swelling, while hematoma describes a localized collection of blood outside of blood vessels, usually resulting from trauma or injury. Each of these conditions involves alterations in blood or fluid dynamics but does not typically indicate a body-wide increase in blood volume like plethora does.