By Dr. Ryan K. Lee and Joanne Hoener
Each year, between 36,000 to 324,000 patients in the United States experience extravasations of contrast media when undergoing an IV contrast-enhanced (CE) CT exam.
Extravasations are defined as accidental extravascular injection of intravascular contrast media caused by dislodgement of the cannula, contrast leakage from the vessel puncture site, or rupture of the vessel wall, and can range from mild impacts requiring no specific intervention to severe impacts requiring a patient to have a surgical procedure to address the extravasation.
These statistics have led Radiology professionals to establish a set of best practices and standards to help address this mostly preventable patient safety risk during CT procedures. This article summarizes established best practices and also describes some techniques to minimize contrast extravasation.
Extravasation of iodinated contrast media can result in injury to surrounding tissues. One of the most feared complications is compartment syndrome, which can be a surgical emergency. Compartment syndrome is caused by increased intracompartmental pressure that compromises tissue perfusion and can cause nerve damage. Extravasations produce a number of challenges including patient complications, patient inconvenience, disruption of workflow, and cost implications related to medical and/or surgical intervention required in severe cases.
In addition to the established methods, which are well described in the literature, more recently, a technique to reduce contrast extravasation has been elucidated. Researchers in the Department of Radiology at the Einstein Healthcare Network led by Dr. Ryan Lee recently conducted a study that lead to a reduction in CT IV contrast extravasation rates. These best practices were recently the subject of a webinar presented by the American Healthcare Radiology Administrators which focused on measures that can reduce the number of contrast extravasations with CE CT exams.
One important observation from the Einstein team was that patients rarely experienced an extravasation with their Cardiac CTA exams. This was interesting because these exams typically use higher flow rates and pressure settings compared to routine CE CT exams. Review of the protocols revealed a key difference with cardiac CE CTA exams compared to non-cardiac exams – cardiac CTA utilized power injection of the pre-injection saline test bolus, whereas all other CE CT studies used manual hand injection. One hypothesis was that utilizing a power injected saline bolus at the same flow rate as the diagnostic injection may better identify IV lines not viable for a contrast injection, compared to hand injection of saline to evaluate the IV.
To test the theory, the team at Einstein changed the protocol for all CE CT exams to use power-injection of the saline test bolus, using the same flow rate as the diagnostic injection. Over the next 15 months, a 53% reduction in the department’s overall extravasation rates was observed. As a result of this finding, power-injection of the saline test bolus at the same flow rate as the diagnostic contrast injection is now routinely utilized for all CT contrast-enhanced exams, and considered a best practice within the Einstein Medical Center.
Technologists can play an important role in the reduction of extravasations. For example, keeping the patient’s arm in the same position for the pre-injection saline test bolus and the diagnostic contrast injection can be beneficial. When a patient places their arm above the head for the diagnostic scan, the IV can change in position and become kinked, increasing the risk of extravasation. Thus evaluating the IV with the saline test injection in the same position as the diagnostic injection can be an important consideration.
Current literature demonstrates that Ultrasound-guided IVs have higher rates of extravasation than other peripheral IVs. This led to a recommendation of avoiding IVs that were placed using Ultrasound guidance for CT IV contrast administration whenever possible.
Radiologist and Technologist need to work together to continue to share information and best practices to address extravasation. The study at Einstein is evidence that the implementation of best practices can help to drive down overall rates.
Best practice recommendations for reducing contrast extravasations:
- Use of a power-injected saline test injection at the same flow rate as contrast injection*
- IV Location – antecubital fossa
- IV Gauge – 20G preferred
- Avoid ultrasound guided IV placements
- Place the patient’s arm in the same position for the pre-injection saline test bolus and the diagnostic contrast injection
- When extravasations occur, use the 5P’s (Pain, Pallor, Pulse, Paralysis and Paresthesia) to evaluate for possible surgical consultation
Dr. Ryan K. Lee
Injection of contrast media for enhanced CT exams plays an important role in diagnosis of pathology. With more than 36 million CE CT exams each year in the United States it is imperative we continually evaluate best practice approaches to help reduce contrast extravasation.
About the authors: Dr. Ryan K. Lee, MD, MBA, MRMD is director of quality and section chief of neuroradiology at Einstein Medical Center. Joanne Hoener R.T.(R)(CT)(MR)-CIIP is clinical specialist – portfolio team at Bayer.