According to a study led by University of Massachusetts Medical School researchers, outpatient chemotherapy treatment is prone to more mistakes than most people believe. "As cancer care continues to shift from the hospital to the outpatient setting, the complexity of outpatient cancer care is growing, with increasing opportunities for medication errors, particularly in the home setting," the authors write. "The findings of our study may help to reframe medication safety priorities for patients with cancer and suggest some practical targets for intervention to improve the care of both adults and children."

Dr. Kathleen E. Walsh and her colleagues in the Journal of Clinical Oncology reported that wrong doses were given in 7.1% of the adult chemotherapy visits, and 18.8 % in pediatric visits. The researchers reviewed nearly 1400 visits at four geographically diverse outpatient clinics and studied the records of 10,995 medications taken by cancer patients at three adult clinic and one pediatric oncology clinic.

The researchers found out of the 112 errors identified 64 had "potential to cause injury," and actual injury occurred in 15 cases. They felt the complexity typical of cancer management was at the root of the high error rates. In pediatric patients 64% of mistakes were ordering errors and most were relatively minor. The serious errors involved administration, especially medications taken at home. "More than half of pediatric errors that had potential for patient harm or did result in patient harm were errors in home medication administration," the researchers said.

They found rates of 9.9 potentially injurious errors per 1,000 medication orders for pediatric patients, versus 5.0 per 1,000 orders in adults. For actual injuries, the rates were
4.3 per 1,000 orders in children and 1.0 per 1,000 orders in adults (P values not reported).

Dr. Walsh and colleagues said, "Orders were sometimes written for the patient's entire chemotherapy regimen for several months at the initiation of treatment, and then doses were adjusted as needed at each clinic visit. Patients therefore had an initial set of orders and then orders might be modified on the day of the visit."

"Requiring that medication orders not be written until the day of administration, following review of laboratory results, may be a simple strategy to prevent a number of the errors that we identified in our study," they added.

The researchers said better communication could have helped prevent many of the errors. They noted that clinics that used complete electronic medical records and computerized order entry had the lowest rate of errors, with only one chemotherapy error in 500 patient visits. In the cases of parents who are dosing their children at home, color-coding or marking lines on syringes has been shown to reduce mistakes. Demonstrating dosing techniques is also beneficial, the researchers said.

They researchers added that in the study they did not include examining medication labels for dispensing errors, nor did they attempt to reconcile actual home medications with those listed on the medical records.

"Improved communication between health care providers and families of patients with cancer about home medication administration may be an important first step for preventing frequent home medication errors among pediatric patients with cancer," they said.

The study was funded by the Agency for Healthcare Quality and Research and the Robert Wood Johnson Foundation.