EXTRAVASATION OF CYTOTOXIC DRUGS

 Despite the utmost care, toxic local tissue reactions do occur.  The onset and intensity of these local reactions range from hours to weeks and from minor skin or venous discolouration to severe local necrosis of the dermis and underlying structures.

Several factors appear to enhance the risk of extravasation.

Anatomic Factors:    Elderly, debilitated patients with generalised vascular disease are at high risk, small diameter veins or those with decreased circulatory dynamics can result in high drug concentrations and extravasations.

Physiological Factors:   An increased potential for systemic as well as local morbidity exists in patients with elevated venous pressure, such as those with superior vena cava obstruction or obstructed venous drainage from axillary surgery, tumour mass or previous radiotherapy to the area.

Pharmacological Factors:   The degree of tissue damage appears to be related to the amount of drug leaked and duration of exposure.

Radiological Factors:   Local reactions may be enhanced in patients who have had previous radiation therapy to the site of cannulation.

Recall phenomenon may occur with doxorubicin and dactinomycin where local effects of previous radiation are reactivated by the drug.

GENERAL

q       A number of non extravasation reactions can occur.  The patient may describe such sensations as pain, stretching or pressure within the vein, originating near the venepuncture site or 7 – 12cm proximal to the site along the vein.  When this type of reaction occurs, cease administration wait and observe, if necessary change the cannula.

q       Doxorubicin can produce a flare reaction along the vein, this is characterised by a redness along the vein and there may be some discomfort or itching sensation.  Flush the vein to ensure extravasation has not occurred and recommence administration of the cytotoxic at a slower rate.

q       Frank extravasation should be assessed by a plastic surgeon as soon as possible.  A necrotic ulcer may progress over several months and lead to extensive tissue damage.  The ulcer may require surgical intervention with debriding and skin grafting.