How Many Grays to Get to the Malfunction of Insulin Pumps? Determining the Effects of Radiation on Insulin Pump Function.

BACKGROUND: The primary objective was to determine if exposure to radiation has an effect on insulin pump function.

METHOD: Four donated insulin pumps were filled with saline and set to identical program modes. They were attached together with a dosimeter and exposed to repeat CT scans.

RESULTS: Insulin Pump 1 experienced a "Prime" alarm and a darkened screen during CT scan radiation exposure; this pump was removed from further radiation exposure after 6 CT scans. Insulin Pumps 2, 3, and 4 all continued to receive 34 more consecutive CT scan exposures with no significant alarms, failures, or malfunctions. Insulin Pump 4 experienced "Low Battery" and "Stuck Button" alarms, both of which were easily fixed. Insulin Pumps 2, 3, and 4 received a total of at least 8576 mrem from 34 CT scans worth of radiation without any significant alarms, malfunctions, or failures. Insulin Pump 1 was monitored after being removed from the study and continued to function normally with the darkened screen.

CONCLUSIONS: It cannot be determined whether Insulin Pump 1 had minor malfunctions due to repetitive use as a demonstration model or due to the radiation exposure. Insulin Pumps 2, 3, and 4 were monitored for 2 additional months following radiation exposure and continued to function normally. Further research studies with a larger number of insulin pumps are warranted to determine the true effect of radiation exposure on insulin pump function.