Abnormal insulin test levels under investigation

July 3, 2007

The patient safety team at the University of Chicago Medical Center is investigating two cases during May and early June in which blood tests showed insulin levels much higher than would normally be observed. Given these two instances and to ensure the highest level of patient safety, the Medical Center has notified appropriate regulatory, enforcement, and oversight agencies.

At this point of the investigation we have not identified a cause for the insulin test results.

"Whatever the investigation concludes, our hearts go out to these patients and their families," said David S. Hefner, President of the University of Chicago Medical Center. "We will do everything we can to discover the cause. The safety of our patients is our highest priority."

The Medical Center has put multiple additional safeguards in place, focusing on the storage, administration and documentation of insulin. On June 22, insulin was removed from each unit's medication refrigerator and placed in locked compartments in the "AcuDose" device, a tightly controlled medication-dispensing system.

Whenever insulin is administered, each order and dose must be double checked by two registered nurses, witnessed, and then documented on the medication administration record by both nurses. Additional monitoring has also been put in place to detect and initiate early and aggressive treatment of low blood sugar.

Since June 6, the Medical Center's Patient Safety Department has worked with physicians, nursing, pharmacy and others to investigate these events and to try to determine whether a medication, laboratory or other error had occurred.

After a root-cause analysis meeting on June 22, because no cause for the insulin test results had yet been identified, the Medical Center notified outside agencies for a range of possible causes. The FDA was notified related to product integrity, the Joint Commission and the Illinois Department of Public Health were notified related to a potential medication error, and the Chicago Police Department was notified due to the possibility of an intentional act. The Medical Center also engaged external experts for an independent investigation and has sent blood samples to an outside facility to conduct an independent analysis of the laboratory results.