ABSTRACT
Evaporation, blood loss, and urinary excretion are the principal mechanisms for losses of fluid during surgery. The magnitude of these losses is often difficult to measure precisely. The accurate assessment or their combined effects, which needs to be based on observation and experience, is one of the major challenges to the anesthesiologist. In contrast, the administration of fluid to the patient is extremely well controlled because virtually all of it is provided as intravenous infusions by the anesthetic team. Besides uptake of fluid from the gut, the only major exception to this rule is systemic absorption of the fluid used to rinse surgical areas free of blood and debris. Here, fluid is administered to the patient without anyone being aware of it.
