Pediatric Corner

Are children at risk for weight-based drug errors?

Pediatric dosing has small margin of error

Children are at high risk for medication dosage errors in the ED, partly because many medication doses are weight-based, says Susan Paparella, director of the Institute for Safe Medication Practices Strategies in Huntingdon Valley, PA.

"There is such a small margin of error when we're talking about pediatric dosing," Paparella says.

In addition, frequent distractions, multiple caregivers, frequency of verbal orders, and overcrowding also put children at higher risk in the ED, she adds. To avoid dangerous drug errors, do the following:

• Measure the weight in kilograms.

"There is always a potential for error when you have to convert the weight from pounds to kilograms, so try to measure the weight in kilos as soon as the child arrives," advises Paparella.

To avoid errors, use only scales that display weights in kilograms, says Michele Morin, RN, clinical nurse educator for emergency services at Children's Hospital Boston. "We have disengaged our scales from being able to display pounds at any time," she says. "When it comes to pediatrics and dosing according to weight, it is vital that only kilograms get measured and recorded for each patient."

When you record a child's weight in the medical record, always use the same unit of measure that you use in your ED, says Nancy Blake, RN, MN, CCRN, CNAA, director of critical care services at Children's Hospital Los Angeles. For instance, when parents are asked their child's weight, they usually respond in pounds because that is how it is measured at the pediatrician's office, she explains.

"If your hospital records and sets their measurements in kilograms, the nurse needs to convert the weight into kilograms," says Blake. If the hospital uses kilograms as their measurement and it is accidentally written in the medical record as the weight in pounds, all of the medication dosages that are computed on that weight will be inaccurate, she warns.

ED nurses at Children's Hospital Boston always calculate medications using "mg/kg," says Morin. "If pounds are inadvertently recorded, the child could get twice the intended dose, which may or may not be lethal depending on the drug and dose," she says. Either way, it is not the intended dose, Morin emphasizes.

At Children's Hospital Los Angeles, weights are measured in kilograms and all documentation in the chart is listed in kilograms. Wherever possible, weigh the child so that medications are based on the actual weight on that day, says Blake.

At Children's Hospital Boston, "We weigh all patients upon arrival to our department," says Morin. "If the child is unable to stand, then a stretcher scale is used if medications are to be given."

They are awaiting the installation of a wheelchair scale to accommodate special needs patients confined to wheelchairs. The wall-mounted scales, which cost approximately $6,000, are manufactured by White Plains, NY-based Scale-Tronix and have a section that folds down if you need to measure a patient on a stretcher, she adds.

Perform an independent double-check for high-risk medications.

Two nurses should check the medication order, dosage, medication vial and patient name, says Blake. "We will be moving to computerized physician order entry in our ED in the near future," she adds. "The alerts and standardizations can be forced at the time the order is placed, which minimizes risk for the patient."

Double-checks are particularly important for narcotics, insulin, and other high-alert medications, says Paparella. "You need to have an independent double check process in place, not only for the calculation, but at the time of administration," she adds. "The nurse verifies with another nurse whether this is the correct dose, syringe, and vial."

The newer "smart pumps" include dose range checking for an extra level of protection for pediatric medications, says Paparella. "They can be programmed to recognize doses and drug concentrations that are out of range," she says.

Do a second check process when doing calculations against the standard weight range for the child's age, recommends Morin. Recently, an ED nurse received an order for 15 mg/26 kg = 390 mg for a 3-year-old boy, who was in the range of 12.05 kg-17.77 kg according to national height and weight charts. When the nurse checked the chart, she realized the weight recorded didn't fit into the guidelines, reweighed the child, and noted that pounds was recorded instead of kilograms — thus the prescribed dose was twice as much as it would have been if kilograms was utilized, says Morin.

• Have orders written as "mg/kg."

Ideally all pediatric orders should be written with two pieces of information, the "mg/kg" dose and the total dose, so that an independent double-check can be done by the nurse, says Paparella. "If you have the dose written as '204 mg,' the nurse could never check if the dose was correct unless she knows the child's weight," she explains. "But if the order was written as '10 mg/kg, total dose 204 mg,' then the nurse could check that calculation and confirm that the physician used the correct weight and came to the correct conclusion."

Sources

For more information on weight-based pediatric dosage errors, contact:

  • Nancy Blake, RN, MN, CCRN, CNAA, Director of Critical Care Services, Children's Hospital Los Angeles, 4650 Sunset Blvd., Mailstop 74, Los Angeles, CA 90027. Telephone: (323) 669-2164. Fax: (323) 953-7987. E-mail: nblake@chla.usc.edu.
  • Michele Morin, RN, Clinical Nurse Educator, Emergency Services, Children's Hospital Boston, 300 Longwood Ave., Boston, MA 02115. Telephone: (617) 355-6624. E-mail: Michele.Morin@childrens.harvard.edu.
  • Susan Paparella, RN, MSN, Director, Consulting Services, Institute for Safe Medication Practices, 1800 Byberry Road, Suite 810, Huntingdon Valley, PA 19006. Telephone: (215) 947-7794. Fax: (215) 914-1492. E-mail: spaparella@ismp.org.