What is extravasation?
Extravasation is a medical term that refers to the leakage of a substance, such as a fluid or medication, from a blood vessel or intended catheter into the surrounding extravascular or subcutaneous tissue. While any intravenous (IV) infusion can leak, the term "extravasation" is specifically used when the leaked substance is a vesicant. A vesicant is a substance with the potential to cause significant tissue damage, such as blistering, ulceration, and necrosis (tissue death), upon infiltration. In contrast, a similar event involving a non-vesicant fluid is typically referred to as an infiltration, which causes less severe, localized effects.
Types of agents involved
- Vesicants: Drugs that can cause severe tissue injury. Many chemotherapy medications are vesicants, along with certain antibiotics and other high-concentration or high-pH solutions. The extent of the damage depends on the drug's concentration, volume, and how long it remains in the tissue.
- Irritants: These agents cause a local inflammatory reaction, such as aching, tightness, and pain along the vein, but typically do not lead to necrosis. A large extravasation of an irritant, however, can potentially cause an ulcer.
- Non-vesicants: These solutions, like normal saline, are generally harmless to tissue upon leakage, causing only localized swelling and discomfort.
Recognizing the signs and symptoms
Prompt recognition of extravasation is crucial for minimizing tissue damage. Symptoms can vary based on the agent involved and the severity of the leak.
Early signs of extravasation
- Pain, stinging, or burning at the IV site
- Localized swelling, puffiness, or tightness of the skin
- Blanching (lightening) of the skin around the insertion site
- Coolness of the skin around the IV site
- Leakage of fluid from the site
- Absence of blood return when the IV is checked
Late or severe signs
- Blistering or peeling of the skin
- Increasing redness and warmth over time
- Skin breakdown and ulceration
- Necrosis (tissue death), indicated by severe pain and darker skin discoloration
- Formation of gas bubbles under the skin
What causes extravasation?
Extravasation can be caused by a combination of mechanical and patient-related factors.
Mechanical causes
- Catheter dislodgement: The IV catheter can be pulled out of the vein, especially with patient movement.
- Vein puncture: The catheter may pass through the side of the vein during insertion.
- Catheter damage: A cracked catheter can cause leakage.
- Inadequate securing: A poorly secured IV line can shift out of place.
- Obstruction: A blockage in the IV line can cause back pressure and lead to leakage.
Patient-related risk factors
Certain patient conditions can increase the risk of extravasation:
- Fragile veins, common in older adults and children
- Impaired neurocognition or communication, which prevents the patient from noticing or reporting symptoms
- Obesity, which can make venous access difficult
- Previous IV drug use or radiation therapy that has damaged veins
- Insertion of IVs over joints, where movement is more likely to dislodge the catheter
Extravasation vs. infiltration
Understanding the key differences between these two complications is vital for proper treatment.
| Feature | Extravasation | Infiltration |
|---|---|---|
| Medication Type | Vesicant (causes tissue damage) | Non-vesicant (does not irritate tissue) |
| Damage Potential | High, can cause necrosis and functional loss | Low, typically limited to localized swelling and discomfort |
| Severity | Often more serious, considered a medical emergency | Less severe, though can lead to complications if large volumes leak |
| Treatment Focus | Requires specific antidotes and close monitoring to prevent necrosis | Generally supportive care, such as warm or cold compresses |
Immediate steps for extravasation management
As a medical emergency, extravasation requires immediate action to minimize harm. Healthcare professionals follow a protocol often summarized with the 'SLAP' acronym. If you are a patient, alert a healthcare professional immediately.
- Stop: Immediately stop the injection or infusion.
- Leave: If an injectable antidote is required, leave the vascular access device (VAD) in place.
- Aspirate: Aspirate any residual drug or solution from the VAD with a syringe.
- Plan: Plan subsequent actions based on the specific drug extravasated and your facility's protocol.
- Remove: The VAD should be removed once the antidote has been administered or if no antidote is required.
Treatments and potential complications
Treatment depends heavily on the specific medication that has extravasated.
- Antidotes: Specific antidotes may be administered. For example, sodium thiosulfate is used for certain drugs like mechlorethamine, while hyaluronidase can be used for vinca alkaloids.
- Compresses: Depending on the vesicant, either cold or warm compresses are applied. Cold compresses are generally used to cause vasoconstriction and limit drug spread, while warm compresses are used for certain drugs (like vinca alkaloids) to increase absorption and dispersion.
- Elevation: Elevating the affected limb helps minimize swelling.
- Surgical intervention: In severe cases, extensive necrosis may require surgical debridement or skin grafts.
- Complications: Severe extravasation can lead to long-term complications including compartment syndrome, permanent nerve damage, infection, and disfigurement.
Preventing extravasation
The best approach to extravasation is prevention. Many strategies are used by healthcare professionals to reduce risk:
- Proper technique: Using proper venipuncture technique and securing the IV line appropriately.
- Vein selection: Avoiding fragile veins, small-gauge catheters, and areas of flexion.
- Monitoring: Continuous and diligent monitoring of the IV site, especially during vesicant administration.
- Patient communication: Educating patients to report any pain or changes immediately.
- Alternative access: Using central venous access devices for prolonged infusions of vesicants.
For more in-depth information, you can read the National Institutes of Health (NIH)'s guidelines on managing extravasation.
Conclusion
Extravasation is the leakage of potentially damaging vesicant drugs into surrounding tissues, posing a significant risk of severe injury. While it can be a distressing event, understanding the signs and symptoms, differentiating it from less-severe infiltration, and knowing the proper immediate response are all vital steps in ensuring patient safety and minimizing long-term damage. With careful technique and diligent monitoring, many cases can be prevented, and prompt action can mitigate the most severe outcomes.
