Conservative measures
If an extravasation injury has occurred, it is important that the infusion is stopped immediately and that aspiration is performed from the venous catheter in question. The identity and concentration of the substance given should be recorded, and the volume and duration estimated. The infusion method should also be noted, whether a gravity drip or one of the various types of active pump. It is useful to draw around any skin lesions with a marker pen so that progression can be monitored. For severe injuries photographs should also be taken.
Beyond this, general advice includes elevation, immobilisation, cooling, warming in certain cases and observation. A range of injectable or topical antidotes have been described for different substances (7). Elevation reduces hydrostatic pressure and is recommended for 48 hours after extravasation.
Cooling seems to relieve pain by reducing nerve conduction, and the ensuing vasoconstriction additionally reduces dispersion of the extravasated substance. The downside is that cooling prolongs the duration of action of many substances. The Poisons Information Centre can often provide valuable assistance (8). With respect to cooling, twenty minutes four times a day is recommended for the first 1 – 2 days, and care must be taken to avoid frostbite. Fluid bags that remain at approximately 4 °C may be used.
Local warming is recommended for certain substances where it is thought that increased blood flow and metabolism may reduce the extent of injury. For most substances, however, warming can lead to exacerbation. It is essential to guard against burns. Fluid bags at temperatures > 40 °C should not be used.
In a study of eight patients with extravasation of cytostatic agents, Giunta and colleagues showed that necrosis was avoided in all those in whom subcutaneous flush-out with 0.9 % NaCl solution was performed at an early stage (9). There is otherwise weak evidence regarding the benefits of early intervention.
The affected area is usually dressed with impregnated gauze, dry gauze and a circular bandage. In general, the use of silver-containing cream is discouraged, especially at early stages, as this can make it difficult to assess the extent of the injury.