Current Concepts in Preventing and Managing Contrast Media Extravasation

Contrast media extravasation (CMEV) occurs when the contrast medium, containing iodine or gadolinium, leaks from the blood vessels into the tissues surrounding the injection site. The consequences can range from simple discomfort to tissue damage in severe cases with implications ranging from edema to necrosis. According to the 2024 edition of the ACR Manual on Contrast Media, the reported frequency of intravenous (IV) contrast media extravasation in adults and children associated with automated injection for computed tomography (CT) ranges from 0.1 percent (1 in 1,000 patients) to 1.2 percent (1 in 83 patients).¹

While automated injection is fast and efficient, it can sometimes lead to the extravasation of large volumes of contrast media, exposing patients to significant risks. Infants, young children, and unconscious or debilitated patients are particularly vulnerable during these injections. Fortunately, in most cases, the extravasation only causes minimal swelling or erythema without long-term sequelae. However, in some cases, severe necrosis and skin ulcerations can occur. Large volumes of high-osmolar contrast media can cause significant tissue damage, and compartment síndrome is one of the most severe complications associated with the extravasation of large volumes.²

It is essential to recognize and manage CMEV promptly to prevent complications and improve the patient's experience. Even what may be clinically considered a minor CMEV may be perceived as significant by the patient and contribute to feelings of dissatisfaction at a stressful time and the notion that "something went wrong" in their care. In more severe cases, a surgeon's opinion may be indispensable.

Accordingly, let us take a closer look at strategies for the prevention and management of CMEV.

Here is a photorealistic image of a hand with slight swelling and redness caused by contrast media extravasation. The image was generated with artificial intelligence. (Image created by Giuseppe Scappatura.)

Essential Keys to Preventing CMEV

• Cannulation procedures. To prevent complications during venous cannulation, it is essential to use appropriately sized needle cannulas and position them in suitable venous vessels. The use of non-ionic, iodine-based contrast media and the selection of the least risky vein, preferably a large antecubital vein such as the cephalic or basilic vein, is recommended. One should avoid using pre-existing intravenous lines and opt for short needle cannulas, adjusting the flow to the gauge utilized. The use of needle cannulas with side holes can be considered to enhance safety.³

• Selection of injection site. Unless there is explicit recommendation to perform injections in the hands or feet, one should avoid doing so. Prior to X-ray irradiation, one should subject the injection to specific monitoring via visual and tactile surveillance.⁴ Any compression of the injected limb should be avoided, and the quality of the catheterization should be checked with a test injection of saline solution, possibly at a higher flow than that intended for definitive use. It is crucial to inform the patient of the risk and to encourage him or her to report any pain. However, keep in mind that a large extravasation can be painless and that a feeling of tension and/or pain may only manifest later. In hospitalized patients, a new cannula should be positioned for intravenous contrast media injection.

To summarize, pertinent injection site-related factors may include:

• suboptimal injection sites such as lower limbs and small distal veins
• scarce subcutaneous tissue on the back of the hand, wrist, back of the foot, and ankle
• injection near a recent puncture site
• infusion duration
• dressings covering the injection site.

• Injection technique. The operator must ensure the correct positioning of the cannula by perceiving a variation in needle resistance during vein perforation. The cannula must pass through the epidermis, dermis, and subcutaneous tissues to reach the vein. Extravasation can occur if the catheter is improperly positioned or dislodged. Elderly patients and infants, with thinner skin and tissues, are more vulnerable. The elderly and those with low muscle mass are more prone to severe injuries from extravasation.

• At-risk patients. One should have a strong awareness of groups who may be more vulnerable to potential CMEV issues. At-risk patients may include:

• unconscious patients
• young children
• patients with language barriers
• obese patients with difficult venous access
• individuals with sclerotic or fragile veins (people with diabetes, those undergoing chemotherapy or radiotherapy, intravenous drug users)
• patients with compromised venous and/or lymphatic drainage, including those with immobilized limbs due to fractures or post-surgical lymphedema.

Other patient factors may include elderly age, arterial insufficiency and trophic changes due to diffuse atherosclerosis, Raynaud's syndrome, vasculitis, diabetes mellitus, phlebitis, lymphopathies, radiotherapy, previous surgeries on the affected venous segment, repeated punctures.⁵

The imaging team must closely monitor these patients throughout the process.6 This allows for timely detection and intervention in case of emergencies or adverse reactions in order to ensure their safety and well-being.

• Contrast media-related factors. Contrast media-related factors also play a significant role. Viscosity (or fluidity) is a property of fluids that indicates resistance to flow in vessels or systems (catheters). Since viscosity determines the flow rate of the contrast medium in a vessel, simply warming the contrast medium to 37°C before administration prevents molecule crystallization and allows for easier and safer infusion. It is particularly important to consider the amount of contrast medium as volumes greater than 100 cc with non-ionic contrast media can be associated with low subcutaneous tissue abundance, vascular damage, or trophic disorders, can increase the risk of complications.

• Checking catheterization quality. Verification of the quality of catheterization is essential to prevent complications. This verification is performed with a test injection of saline solution. During this test, the patient should be informed of possible risks and encouraged to report any pain or discomfort.

Here is a photorealistic image depicting an arm with contrast media extravasation. The image was generated with artificial intelligence. (Image created by Giuseppe Scappatura.)

Pertinent Insights on Automatic Injectors

Contrast injectors are crucial tools in medical imaging procedures. Modern automatic injectors are equipped with advanced pressure monitoring systems with graphic displays showing the real-time injection flow profile. If abnormal flow resistance is detected, these devices can automatically or semi-automatically stop the injection, preventing potential harm to the patient.

Types of Automatic Contrast Media Injectors

Peristaltic Pump Injectors

Operation:

• They use a sequential compression mechanism of a flexible tube through rotating rollers.

• The fluid is pushed through the tube, creating a continuous and controlled flow.

Advantages:

• Reduced risk of contamination since the fluid only contacts the inside of the tube.

• Ability to maintain precise and consistent flow, which is ideal for continuous fluid delivery such as contrast media.

• Ease of maintenance with the flexible tube being the only component requiring regular replacement.

CT motion™ and ulrich easyINJECT Max™ (Ulrich Medical) and CT Expres™ 4D(Bracco) are a couple of the peristaltic pump injectors available.

Piston Injectors

Operation:

• They use a piston to push the fluid through a cylinder, allowing precise control of the injection quantity and speed.

• Often equipped with sensors to monitor pressure and flow, stopping the injection in case of abnormal resistance.

Advantages:

• High precision in fluid dosage, particularly useful for applications requiring exact volumes of contrast media.

• Ability to generate high pressures, making them suitable for rapid and voluminous injections.

• Advanced safety systems to prevent extravasation and other complications.

Medrad Centargo (Bayer) and OptiVantage™ Multi-use (Guerbet) are among the piston injectors available on the market.

Automatic injectors for contrast media infusion represent advanced and safe technology for the administration of contrast media during medical imaging procedures, offering various benefits in terms of precision, safety, and maintenance. These modern devices are equipped with advanced pressure monitoring systems, including graphic displays showing the real-time injection flow profile. If abnormal flow resistance is detected, the injectors can automatically or semi-automatically stop the injection, preventing potential harm to the patient.

Various injectors display a graph of the working pressure profile adopted at that moment by the machine based on the examination conditions, such as flow rate, contrast media viscosity, and the patient's condition. This graph may indicate an increase in pressure in case of line obstruction or a decrease in working pressure in case of extravasation. Since the working pressure profile is not a sensor, the interpretation of whether one of the two situations has occurred is up to the operator.

Additionally, the injector allows the user to configure the injection performance when the pressure approaches the programmed limit. There are two main options.

Reduction of the predefined maximum flow rate. This setting ensures that the system prioritizes maintaining the flow rate and automatically reduces it to prevent exceeding the pressure limit.

Sensitivity of the predefined pressure limit. This setting provides the system with greater flexibility, allowing the desired flow rate for the injection to be maintained while limiting pressure near the programmed limit.

Moreover, some injectors offer the possibility of performing a test injection with saline solution to verify the patient's vein patency. During this procedure, the operator can vary the test injection speed in real time, allowing an accurate assessment of the vein's condition.

For early recognition of extravasation, one may consider extravasation detection accessories (EDAs). These devices incorporate biophysical measurement techniques such as bioimpedance, thermal mapping, radiofrequency reflection/absorption, optical refraction/reflection, ultrasound mapping, fluid pressure measurement, and exhaled carbon dioxide detection.⁷

When CMEV Occurs

The management of extravasation includes the immediate interruption of the injection and documentation of the extravasation through X-ray, CT, or MRI of the affected area. The diagnosis is generally clinical, and imaging is not typically indicated for detection. The extent of tissue damage depends on the contrast medium used and the catheter's location. More extensive damage occurs with the involvement of tight subfascial compartments compared to broader superficial subcutaneous layers.

Symptomatic extravasations can be treated by elevating the limb above heart level and using cold compresses. Cooling the area with a cold compress for 15 to 60 minutes three times a day for three to four days has an anti-inflammatory effect through vasoconstriction and is widely recommended. Surgical consultation is necessary if severe injury is suspected. Routine use of hyaluronidase or corticosteroid injections, as well as site aspiration, is not recommended. Topical application of silver sulfadiazine ointment and steroid cream three or four times a day has been proposed to soothe irritated skin, reduce inflammation, and prevent infection in case of blisters, although the effectiveness of this treatment is uncertain.⁸

Assess the potential severity by estimating the injected contrast medium volume, observing signs of poor tolerance, and checking distal perfusion. Monitor for skin changes and significant edema, and check for paresthesia, segmental pain, hypoesthesia, reduced muscle strength, and decreased pulse. Next-day follow-up is recommended to monitor the progression of severe cases.

When Should You Pursue Surgical Consultation?

Surgical consultation is necessary in cases of:

• Severe pain
• Significant swelling
• Altered tissue perfusion
• Changes in the sensitivity of the affected limb
• Skin ulceration or blisters

The most commonly reported severe injury after low-osmolality contrast media (LOCM) extravasation is compartment syndrome, resulting from mechanical compression. Compartment syndrome is defined as increased pressure within a closed compartment causing impaired microcirculation of the tissue within. This condition is more likely after the extravasation of large volumes of contrast media but has also been observed after small volume extravasation, especially in less spacious areas such as the ventral or dorsal surfaces of the wrist.

Compartment syndrome can develop immediately after extravasation or result from swelling that occurs hours later. Signs such as painful active flexion, passive extension, neurosensory disturbances, and increased swelling indicate the need for decompressive fasciotomy. The volar forearm and hand are at higher risk. In severe cases, urgent surgical consultation is necessary, and procedures performed within 90 to 300 minutes have a favorable prognosis. For extravasations greater than 150 ml, surgical consultation is recommended regardless of clinical severity.

Other Considerations in Managing CMEV

Other factors that may influence the management of CMEV include:

• a patient’s inability to communicate effectively.
• severely ill or debilitated patients.
• history of vascular or tissue injuries
• use of anticoagulant or antiplatelet medications, leading to increased risk of hemorrhagic complications.

In Conclusion

The prevention and management of CMEV requires a combination of accurate injection techniques, appropriate use of contrast media, and timely management of complications. Educating medical staff and patients about the risks and preventive measures is crucial to reducing the incidence and impact of CMEV. By adopting appropriate techniques and informing staff and patients, it is possible to reduce the incidence and impact of this complication along with improving the quality of care and the overall patient experience.

Mr. Scappatura is a radiology technician at the UOC of Radiology of the Grand Metropolitan Hospital in Reggio Calabria, Italy. He is a member of the multidisciplinary CAR-T therapy team and the multidisciplinary prostate cancer team.

References

1. ACR Committee on Drugs and Contrast Media. ACR Manual on Contrast Media 2024, pp. 21. American College of Radiology (ACR). Available at:https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf . Accessed July 26, 2024.

2. Stavrakakis IM, Daskalakis II, Detsis EPS, Karagianni CA, Papantonaki SA, Katsafarou MS. Hand compartment syndrome as a result of intravemous contrast extravasation. Oxf Med Case Reports. 2018;2018(12). Available at: https://academic.oup.com/omcr/article/2018/12/omy098/5194305 .

3. European Society of Urogenital Radiology (ESUR). ESUR Guidelines on Contrast Agents, 10th edition, pp. 26. Available at: https://www.esur.org/wp-content/uploads/2022/03/ESUR-Guidelines-10_0-Final-Version.pdf . Accessed July 26, 2024.

4. ACR Committee on Drugs and Contrast Media. ACR Manual on Contrast Media 2024. pp. 17. American College of Radiology (ACR). Available at:https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf . Accessed July 26, 2024.

5. Roditi G, Khan N, van der Molen AJ, et al. Intravenous contrast medium extravasation: systematic review and updated ESUR Contrast Media Safety Committee Guidelines. Eur Radiol. 2022;32(5):3056-3066.

6. ACR Committee on Drugs and Contrast Media. ACR Manual on Contrast Media 2024. pp. 23. American College of Radiology (ACR). Available at:https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf . Accessed July 26, 2024.

7. Hirata I, Mazzotta A, Makvandi P, et al. Sensing technologies for extravasation detection: a review. ACS Sensors. 2023;8(3). Available at: https://pubs.acs.org/doi/10.1021/acssensors.2c02602 . Accessed July 26, 2024.

8. ACR Committee on Drugs and Contrast Media. ACR Manual on Contrast Media 2024. pp. 22. American College of Radiology (ACR). Available at:https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf . Accessed July 26, 2024.