CONTRAST EXTRAVASATIONS ENCOUNTERED IN COMPUTED TOMOGRAPHY STUDIES – A 3 YEAR RETROSPECTIVE STUDY IN A TERTIARY CARE CENTRE IN SOUTH INDIA Abstract ID:

CONTRAST EXTRAVASATIONS ENCOUNTERED IN COMPUTED TOMOGRAPHY STUDIES – A 3 YEAR RETROSPECTIVE STUDY IN A TERTIARY CARE CENTRE IN SOUTH INDIA

Abstract ID: IRIA - 1205

• Aim: To identify the incidence and severity of contrast extravasation encountered in intravenous iodinated contrast enhanced cross sectional imaging

• Methodology & materials: 3 years retrospective study from November 2011 - October 2014 using data collected from PACS, surgical records, medical records, audit book in radiology. Clinical severity graded into mild, moderate and severe according to the clinical findings and outcome.

Materials & methods:

• CT scans were performed on Siemens – Emotion 16, Philips brilliance 6 and GE HD750

• Contrast agents used – Ioversol, Iopamidol, Iodixanol and Iohexol

• Injection method - automatic contrast injector (Imaxeon) or manual injection

• Manual injections were performed when patients were having CT brain, when patients had poor IV access

• Injection rates - between 0.5 to 6 mL/s depending on individual study requirements.

• Volume - between 40 and 150 mL

Our institution protocol when an event occurs:

• When an event occurs -> Infusion will be stopped immediately -> check the signs and symptoms -> management either on an OP basis / IP basis according to the clinical severity -> then following details are recorded:

1. Name

2. Hospital ID

3. Sex

4. Study details (Abdomen, thorax / neck & thorax, angiogram, brain)

5. Date of study

6. Patient is on chemotherapy or not

7. Mode of injection (automatic / manual)

8. Amount of extravasation

9. Treatment given – OP / IP conservative (limb elevation, ice packs, MgSO4 ointment) / surgery (fasciotomy)

10. Number of days of admission if any

11. Outcome (complete recovery, morbidity, mortality)

Rate of contrast injection given in our department (with pressure injector):

• CT abdomen – 3ml/sec

• CT neck / thorax – 2-3/sec

• CT angiogram – 4-5ml/sec

Pressure used in automatic injector

250-300psi

Volume

• Adult – maximum 2ml / kg

• Paediatric age – maximum 1.5 ml / kg

• Total number of contrast enhanced studies – 69379

• Total number of events – 53

• All the cases were adults

• All of them recovered completely

Results

Incidence - 0.08 %

Mode of injection

Treatment

Surgery - 0

CT Studies

DISCUSSION

• Our observed extravasation rate of 0.08% (53 of 69379 patients) is much less when compared other series in which automated mechanical injectors were used, where the extravasation rates ranged between 0.25% and 0.9%

• As in previous series, in our study few of the extravasations involved large volumes of contrast material.

• Although the most frequently observed range of extravasated contrast material volumes was 10–40 mL

• In our study, no event occurred in the paediatric age group

• Only 2 extravasations encountered on manual injection, however this was not taken into account as it was done only for a small number of studies (CT brains).

• In our institution, we intimate and consult hand surgeons for major cases.

• Most of the patients were conservatively treated and recovered completely without any residual morbidity like skin ulceration / necrosis

• In this study, the rate of extravasation was more in those patients who were not on chemotherapy (as it is thought to block the cannula / cause vessel wall inflammation)

• Majority of the cases were encountered in CT abdomen / pelvis study (rate of injection – 3ml/sec)

1. It was a retrospective review and was entirely dependent on the quality, accuracy, and completeness of the extravasation data forms and the medical records.

2. Some information like injection site, intravenous catheter gauge and patient symptoms was not provided for a few patients.

3. Follow up was not complete for all of the known extravasations.

LIMITATIONS

• Contrast extravasation is a well-known complication of contrast-enhanced CT scanning and can also occur in MRI studies

Risk factors:

1. Increased incidence with automated power injection because large volumes can extravasate in a short period of time 

• with manual injection, extravasation is thought less likely, as there is direct supervision of contrast administration

2. Patient-related factors:• elderly patients• emaciated patients• oedematous patients• confused patients

CONCLUSION

Risk factors

3. Site of venous access: • higher percentage of leakage in the venous access in the dorsum of the

hand, wrist, foot and ankle • likely related to a smaller amount of subcutaneous tissue and the fact that

veins are more fragile on these regions

4. Gauge of intravenous catheter: over 22G (same for 18G and 20G) 

5. High-osmolar contrast medium

Pathology1. Tissue damage due to direct toxic effect of the agent

2. Increased intra-compartmental pressure in the interstitium over its capillary perfusion pressure, due to the accumulation of contrast

Capillary blood flow is compromised

Oedema within the soft tissue increases pressure further

Compromises venous and lymphatic drainage

Compromise arteriolar perfusion Ischemia

Worsens

Clinical features

Initial signs & symptoms:- Swelling or tightness

- Stinging or burning pain

- Erythema

Sequelae:- Compartment syndrome – Intra-compartmental pressure >30 mmHg as an

indication for fasciotomy or pressure <30 mmHg difference between intra-compartmental pressure and diastolic blood pressure

- Skin ulceration

- Skin necrosis

Evaluation

- Severity and prognosis of a contrast medium extravasation injury are difficult to determine on initial evaluation of the affected site. Hence close clinical follow-up for several hours is essential for all patients.

Pressure injectors are indispensable:

1. Tight "Bolus" of Contrast Media – maximum, uniform enhancement and visualization in the final image without a lot of waste

2. Precise timing of the contrast media delivery

3. Consistent, reproducible, patient-specific results - allows physicians to

easily customize injection protocols for specific studies and specific patients.

4. Time saving

Stop infusion, remove the catheter and notify the overseeing radiologist

Conservative measures and inform hand surgeons• Limb elevation• Ice packs• Mag. Sulphate Ointment

Shift under the care of hand surgeons if there is,• skin blistering• altered tissue perfusion• increasing pain• change in sensation distal to the site of

extravasation

Discharge if there is complete recovery and no progression for the next 24 - 48 hours

Worsens

Surgery - Fasciotomy

MANAGAMENT GUIDELINES

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