Infiltration (medical)

Infiltration is the diffusion or accumulation (in a tissue or cells) of substances not normal to it or in amounts in excess of the normal. The material collected in those tissues or cells is also called infiltration.

Infiltration is sometimes used to define the invasion of cancer cells into the underlying matrix or the blood vessels.

Etiology
Infiltration may be caused by:
 * Puncture of distal vein wall during venipuncture
 * Puncture of any portion of the vein wall by mechanical friction from the catheter/needle cannula
 * Dislodgement of the catheter/needle cannula from the intima of the vein which may be a result of a poorly secured IV device or the selection of which venous site is used.
 * Improper cannula size or excessive delivery rate of the fluid

Signs/Symptoms
The signs and symptoms of infiltration include:
 * Inflammation at or near the insertion site with swollen taut skin with pain
 * Blanching and coolness of skin around IV site
 * Damp or wet dressing
 * Slowed or stopped infusion
 * No backflow of blood into IV tubing on lowering the solution container.

Nursing Treatment
The use of warm compresses to treat infiltration has become controversial. It has been found that cold compresses may be better for some infiltrated infusates and warm compresses may be more effective for others. It has also been documented that elevation of the infiltrated extremity may be painful for the patient. To act in the best interest of the patient, following IV infiltration, consult with the physician for orders regarding compresses and elevation.