Extravasation

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**Extravasation**
*Classification & external resources*
MeSH	C21.866.371

This article is about fluids in medical contexts. For the inflammatory process, see diapedesis.

Extravasation refers to the leakage of a fluid out of its container. In the case of inflammation, it refers to the movement of white blood cells from the capillaries to the tissues surrounding it. In the case of malignant cancer metastasis it refers to cancer cells exiting the capillaries and entering organs.

It is frequently used in medical contexts, either referring to urine, or to blood.

EXTRAVASATION OF MEDICINAL DRUGS during intravenous therapy, a side-effect which can and should be avoided, and which can lead to loss of an arm in extreme cases:

Extravasation is the accidental administration of intravenously (IV) infused medicinal drugs into the surrounding tissue, either by leakage (eg, because of brittle veins in very elderly patients), or directly (eg, because the needle has punctured the vein and the infusion goes directly into the arm tissue).

Extravasation can cause: 1) Pain, reddening, irritation, etc (ie, only slight damage) on the arm with the infusion needle, or 2) severe damage up to tissue necrosis (ie, parts of the arm tissue die). As mentioned, it even can lead to loss of an arm in extreme cases.

Medicinal drugs which cause only slight damage on the arm with the infusion needle if extravasated are called "irritants", and medicinal drugs which cause severe damage up to tissue necrosis if extravasated are called "vesicants".

Occurrence is possible with all IV drugs, but of course is a big problem with cytotoxic drugs for the treatment of cancer (ie, during chemotherapy). Percentage of patients affected by extravasation may be as high as 10%. Nobody really knows, since extravasation is often unnoticed and/or undocumented, especially if not severe.

However, the end result can (not must, but can) be devastating, even if the best treatment is initiated as soon as extravasation is noticed, especially in vesicant extravasation.

The best "treatment" of extravasation is prevention! This is so because there is no real treatment for extravasation. There are a lot of treatments, and these should be applied in case of extravasation, but their efficacy is modest. If there is tissue necrosis (ie, parts of arm tissue have died), surgical reconstruction may be helpful. However, the best "treatment" of extravasation remains prevention.

(Here is a short overview of treatment, but remember: The best "treatment" of extravasation remains prevention. Back to treatment: Stop infusion immediately. Put on sterile gloves. Replace infusion lead with a disposable syringe. While doing this, do not exert pressure on the extravasation area. Now slowly aspirate back blood back from the arm, preferably with as much of the infusion solution as possible. Next, remove the original cannula or other IV access carefully from the arm. Elevate arm and rest in elevated position. If there are blisters on the arm: Aspirate content of blisters with a new thin needle. If for the extravasated medicinal drug substance-specific measures apply, carry them out; for instance, topical cooling, DMSO, hyaluronidase or dexrazoxane may be appropriate; for more information on substance-specific measures see, for example, the textbook "Extravasation of cytotoxic agents", Authors: I Mader and others, Springer Publishing House. Pain management is very important for the patient, as are full documentation and prevention of superinfection. If there is superinfection, get an antibiogram and consult with an infectious diseases specialist. Of course, regular controls and aftercare are necessary. IF the extravasated medicinal drug is a vesicant: 1. Don't: Do not flush the IV access. No moist compresses. No alcohol compresses. No occlusive dressings. 2. Consult a physician with experience in the treatment of extravasation and a reconstructive surgeon early in the course of extravasation! 3. Such cases may necessitate skin grafting and intensive physiotherapy.)

To prevent extravasation: Venipuncture and placement of the cannula (or other IV access) by experienced personnel only. If personnelwise possible for all patients; if not enough personnel at least for patients prone to extravasation, eg patients with hardly visible veins, very obese patients, very elderly patients, young children, etc. No multiple venipunctures in the same area. Choose a large, intact vein with good blood flow for the venipuncture and placement of the cannula. Do not choose inadvertently "dislodgeable" veins, eg dorsum of hand or vicinity of joints, if an alternative vein is available. Use thin cannulas (those with high gauges). Check (a) the position of the cannula by aspirating blood as well as (b) the patency of the vein by flushing with the carrier solution (eg, 0.9% NaCl solution) before beginning the IV infusion. Observe infusion at least for the first 10 minutes and do the same every hour. Ask medical student/student nurse/patient/patient's family to do this for you if you do not have the time. Instruct them how to observe an infusion and to alert you as soon as possible if something seems to "go wrong": The IV infusion should be a freely-flowing infusion; the arm with the infusion should not "begin to swell" (oedema), "get red" (erythema), "get hot" (local temperature increase), and the patient should not notice any irritation or pain on the arm; otherwise, stop infusion immediately! The infusion should consist of a suitable carrier solution with an appropriately diluted medicinal/chemotherapy drug inside. After the IV infusion has finished, flush the vein "clean" with only the carrier solution. Finally, an excellently and very cleanly placed central line (= central venous catheter) is a huge advantage while infusing vesicant drugs.

In a few languages, eg in German, extravasation is called paravasation.

Examples of vesicant medicinal drugs (ie, the sort that is dangerous if extravasated) are: (a) Cytotoxic drugs: Amsacrine, cisplatin if > 0.4 mg/mL, dactinomycin, daunorubicin, docetaxel, doxorubicin, epirubicin, idarubicin, mechlorethamine, mitomycin C, mitoxantrone, oxaliplatin, paclitaxel, vinblastine, vincristine, vindesine, vinorelbine, etc, and (b) Non-cytotoxic drugs: Alcohol, aminophyllines, chlordiazepoxide, diazepam, digoxin, nafcillin, nitrogylcerine, phenytoin, propylene glycol, sodium thiopental, tetracyclines, etc. This list is not complete.