Duke Health System officials spent the spring and summer dealing with the consequences of a winter mix-up in which hydraulic fluid was confused for detergent and used in the washing of surgical instruments at two Duke-affiliated community hospitals.
The hydraulic fluid was used in place of detergent through much of November and December at Duke Health Raleigh and Durham Regional; none was used at Duke Hospital. The mistake was discovered by officials in late December 2004, and letters informing the 3,800 patients affected were mailed out the first week of January.
The letter noted that Duke infectious diseases experts, who regularly monitor infection rates at community hospitals in North Carolina, reported that there was no out-of-the-ordinary spike in infection rates at the two hospitals in November and December.
The mix-up occurred when elevator-company workers drained used hydraulic fluid into empty detergent drums, which were then returned to the detergent company, Cardinal Health, and in turn shipped back by Cardinal as detergent to several community hospitals.
In June, several patients and lawyers spoke out, concerned that Duke was not providing full disclosure, asking why officials had not questioned the "greasy" instruments and corrected the problem sooner. Some who experienced post-operative problems said they worried that these resulted from improperly cleaned tools.
Duke officials said their response to inquiries was delayed as they waited for the results of two independent studies into the potential impact of the mix-up. A study released June 15, conducted by physician William Rutala, director of the University of North Carolina's statewide program in infection control and epidemiology, confirmed that the sterilization process had not been compromised.
The cleaning process actually consists of several stages, according to Duke officials. After instruments are rinsed with diluted detergent, they undergo a sterilization process that involves rinsing at high temperatures and then "the equivalent of pressure-cooking in a 270-degree-Fahrenheit oven."
Questions also were raised whether the presence of chemicals and possible traces of heavy metal particles in the fluid from the elevator shafts could potentially harm those who came in contact with it. A second study, conducted by Research Triangle Institute International and completed in late June, found that the amount of fluid remaining on the tools after completing the cleansing process was very small. Duke toxicologist and physician Woodhall Stopford reviewed the analysis, as well as chemical safety information and an ingredients list provided by the maker of the fluid, Exxon-Mobil, and found that none of the chemicals was likely to be harmful in the tiny amounts patients were exposed to. The results of these studies also were communicated in letters to the 3,800 patients.
In an opinion piece published July 15 in the News & Observer, Victor J. Dzau, chancellor for health affairs and president of Duke's health system, reflected on the year's events. "While we continue to monitor the situation and carefully assess the facts, we currently know of no link between any illness and the pre-sterilization incident.
"Looking ahead, I am committed to taking whatever steps are necessary, even painful steps, to ensure that no similar errors occur in the future. We must uphold the trust of the more than 300,000 patients a year who seek care within our system."
In August, Duke sent letters to patients informing them that a long-term program, based on an established method used by the FDA to track potential side effects of drugs, was being set up to monitor their health.