Perioperative Intravenous Fluid Therapy for Adults

Fluid and electrolyte homeostasis is a highly evolved mechanism, designed to conserve sodium and water in periods of illness. The advent of intravenous fluid therapy has challenged this system to operate in an opposite manner and excrete perioperatively administered sodium and water. Excessive fluid generates oedema and is associated with organ dysfunction and even death. Numerous fluid types have been developed, with recent large scale randomized controlled trials identifying clear signals of harm with hydroxyethyl starches, culminating in their withdrawal from clinical practice. Prescribing intravenous fluids requires a clear understanding of the requirement for fluid, the formulation of the various solutions available, the scientific evidence for and against these solutions, and the ability to identify a patient’s pathology, volaemic status and response to the fluid administered.