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Online TPN Calculator Cuts Medication Errors

Kate Traynor

By replacing a paper document with an online version of the form, the neonatal intensive care unit (NICU) at Johns Hopkins Children's Center in Baltimore has dramatically decreased medication errors associated with total parenteral nutrient (TPN) solutions, according to a report in the April issue of Pediatrics.

Children's reported its NICU averaged 10.8 prescribing errors per 100 TPN orders during a six-week control period before the online form—dubbed TPNCalculator—was implemented. The error rate dropped to 4.2 errors per 100 orders during an initial trial of the online form and then fell to 1.2 errors per 100 orders after the program was refined.

The most common errors during the control period were inappropriate osmolality of the TPN solution, calculation errors, and other "knowledge deficiencies," according to the report. When the refined version of TPNCalculator was put in place, osmolality errors decreased significantly and calculation errors and so-called errors of omission were eliminated.

Kim G. Conner, senior clinical nutrition support pharmacist and a coauthor of the report, said that TPNCalculator had been designed to look like the paper TPN order sheet, but with the calculation steps removed.

Conner explained that when he and his colleagues had examined the TPN ordering process with the aim of improving it, they discovered that "about 32 different calculations" had to be performed to properly complete the order sheet.

"It would end up taking a lot of pharmacy time, because the doctor would write the order, we would get a copy of the order, and then we would have to go through and double-check all of those 32 calculations," Conner said. "It kind of took away from our time of looking at the kids clinically."

Instead of hiring a programmer, the NICU relied on physician Christoph Lehmann to create TPNCalculator. Conner described Lehmann, the lead author of the Pediatrics article, as a neonatologist with "a background in computers."

"He basically put it all together in about three weeks," Conner said. He noted that, because the NICU staff had both clinical and programming skills, the group was able to quickly identify problems with TPNCalculator and refine it to meet the unit's needs.

According to the report, a survey of physicians indicated that they were satisfied with the program and found it easy to use, helpful, protective against errors, and a time saver. Conner added that physicians at Hopkins "found that it was easy to transfer from the old form to the new form."

In fact, he said, TPNCalculator's popularity has spawned related online programs for the NICU.

"We have an infusion calculator," Conner said. "We have a tutorial for physicians to take prior to working in our intensive care units, so that they know the proper way of writing orders for pediatrics."

Conner said that TPNCalculator is now in use throughout Children's as well as the NICU at Hopkins' Bayview facility. He added that other institutions have expressed interest in using TPNCalculator.

Conner said that Hopkins staff members will "do the best we can to make it available for other institutions." He noted that the program is best suited for hospitals that follow Hopkins' individualized approach to TPN therapy.

"For us, we individualize to the child," Conner explained. "We look at hydration, calories per kilo, grams of fat, grams of protein....We look at sodium and we look at potassium and we look at magnesium, and then we ask the physician to decide whether or not they want all acetate, all chloride, balanced [anions], or anything in-between."

The calculator can be viewed online at the Hopkins Web site.

Although Conner views TPNCalculator as a success, he said he has some "minor" concerns about the program.

"It's set up in such a way that there are a lot of alerts and warnings" for users, Conner said. The report states that 62 "reminders and alerts" are built into the program. Conner noted that physicians can bypass the alerts and possibly ignore something important.

"But that doesn't mean that we don't catch it on our end when we get the order," he said of the pharmacy staff.

Conner said that another potential concern deals with the education of medical residents who cycle through the NICU. Because TPNCalculator handles the mathematical components of TPN order entry, Conner said, residents might complete their rotation without learning how to calculate TPN orders for pediatric patients.

But overall, Conner said, Hopkins' success with TPNCalculator has a positive message for pharmacy and for patient care.

"Through the use of individualized programs that are tailored to your institution, you can increase your efficiency, decrease errors, and spend more time on clinical applications," he said.