An update on extravasation: basic knowledge for clinical pharmacists.

Extravasation is the leakage of intravenously administered solution into surrounding tissues, which can cause serious damage to the patient. The impact of extravasation is mostly determined by the localisation and volume of extravasation, but the physicochemical properties of the drugs are also important. In this paper a stepwise approach to managing an extravasation is described, with recommendations on the role of the pharmacist. Information on osmolality, pH, pKa and the buffering capacity of drugs is given in relation to extravasation, which is summarised in a practical crash card that can be used in clinical practice.