RSNA: Power-injection contrast media yields low extravasation rates

CHICAGO—Power-injected intravenous contrast media yields low contrast extravasation (CE) rates, according to a recent study presented Dec. 1 at the annual meeting of the Radiological Society of North America (RSNA).

Martin L. Gunn, MB, ChB, with the University of Washington, presented the study and said in addition to examinging CE rates and complications from power-injected IV, the researchers also wanted to determine the impact of a new process for real-time pressure monitoring of injections.

The study examined 80,045 contrast injections between 2006 and 2013, in which there were a total of 290 CE events, a rate of 0.362 percent. All injections were non-ionic low-osmolality contrast media.

The study found significant differences based on gender. “There did seem to be a bit of bias with contrast extravasation,” Gunn said. “Females were more likely than males to undergo extravasation.”

Additionally, Gunn noted there was a small increased probability of CE if the patient is older. The average age for CE events in the study was 56.

In 2008, Gunn said, the study institution implemented a new process where one technologist monitored the patient at the contrast media injection site while a second technologist monitored the power injection system on a computer screen.

“If we compare data from before 2008 to afterwards, we found no significant reduction in the contrast extravasation rate,” he said.

Extravasation events were found to result in a high rate of sub-optimal CT reports.

In 44.3 percent of CE cases, the report was not high enough quality and rated sub-optimal. Gunn said that there was limited diagnostic accuracy or the scan was abandoned completely in those cases.

In those without sub-optimal diagnostic report labels, most patients were re-injected at the time of the CT scan, according to the presenter.

“In the end, we found the risk of complication during intervention due to CE is extremely low,” Gunn said. “In our series, approximately two in 80,000 patients had a serious event. In addition, using the real-time pressure monitoring did not reduce CE events in our study.”