It was reported that a per-diem nurse started the iv fluids in the right antecubital. The total volume of contrast was approx 140 ml and the injection flow rate was set for either 2. 0 or 2. 5 cc/sec. The eda patch was placed over the angiocath and the nurse monitored the injection site for a short time inside the room. The pt did not complain of any pain and the nurse checked the arm before the pt left and did not notice any signs of swelling. Upon viewing the scan, it was noticed by the radiologist that there was no contrast on the films. At this point, the x-ray and iv bag were checked, although no contrast was noted in the bag. Later, the pt's daughter called the facility and stated that her mother's arm was swollen. The nurse instructed the pt to keep the arm elevated and apply cold compresses. The nurse indicated that the pt had large arms and that the extravasation (which was likely the entire 140 ml of contrast) had to be deep.

It is the opinion of e-z-em's med affairs dept that this event appears to represent a false negative, as the eda did not detect the extravasation at 20 cc's as intended. Extravasations greater than 20 ml do have the potential to cause serious harm and injury. However, in a larger pt, this risk is modestly reduced due to the amount of tissue into which the contrast could diffuse. This pt suffered no serious effects as a result of this extravasation other than a small amount of discomfort that was alleviated by arm elevation and cold compresses. E-z-em's manual and operations guide includes a caution and warning section relating to minimizing the potential for extravasation. E-z-em's labeling clearly states that the eda feature is an "auxiliary device feature which assists users in the detection of a possible extravasation" and "it is not intended as a substitute for observation and intervention by a trained healthcare professional. ") it is an unrealistic expectation that the eda device which uses low level electrical signals for extravasation detection purposes provide 100% sensitivity. Since it is not possible to determine if the circumstances behind this false negative condition are solely user related, device related, or some combination thereof, corrective and preventative actions include, but are not limited to, training, site monitoring, and engineering eval. E-z-em shall proceed with the following: 1. Retraining of clinicians at sites which experience a false negative to make sure that the eda patch is located and connected properly. 2. Product mgmt will monitor for an observable trend of false negative conditions developing from an improper set-up of the eda patch by field users. If such a trend is evident, long term preventative action would likely be improvements to device labeling, customer training techniques, and the eda patch's user interface. 3. E-z-em engineering in conjunction with product mgmt will monitor for an observable trend of false negative conditions which can be attributed to the device's failure to detect clinically observed extravasations. E-z-em is currently in the process of using eda systems with data acquisition capability at selected sites for the purpose of performing post market surveillance. The data collected from this surveillance effort will guide planned product improvement to increase the effectiveness of the eda device.