Use these tips to prevent weight-based drug errors

A young girl of about 6 or 7 years old came to the ED at Northwest Community Hospital saying she felt weak. "She was mildly tachycardic, but otherwise did not look bad," recalls Barbara Weintraub, RN, MSN, MPH, CEN, the facility’s coordinator for pediatric emergency services. This child’s subsequent work-up revealed new onset diabetes with diabetic ketoacidosis. An intravenous line was started, and insulin therapy was initiated. Because the girl had not been weighed at triage, the primary nurse asked the mother how much the patient weighed.

"The mother responded with what she thought the girl’s weight was at the last checkup," says Weintraub. "Unfortunately, the girl had several siblings, and in her distraught state, the mother gave the weight of one of the other older children." The girl’s insulin therapy was calculated on this inaccurate dose, says Weintraub. "Fortunately, the error was caught before any serious consequences occurred," she says.

A recent study looked at 1,532 children treated in a pediatric ED and found that one in 10 had a medication error. The most common cause of the drug errors were mistakes in dosages.1 Unlike adults, who receive standard doses of medications, children receive every single medication calculated on a per-weight basis, says Weintraub. "This increases the number of opportunities for errors," she says.

Here are effective strategies to prevent weight-based dosage errors:

• Always weigh the child. In pediatrics, weight is a basic vital sign, stresses Weintraub. "Every child who comes to the ED, regardless of chief complaint, should be weighed," she says. The triage nurse may not weigh the child because there is no apparent medical condition that requires medication administration, adds Weintraub. The weight always should be measured unless the child is unstable or has an injury that contradicts standing for a minute or less, she says. It’s a mistake to ask parents for the child’s weight, Weintraub explains. "This presupposes that parents know their kids’ weights," she says. Parents may guess, estimate incorrectly, or inadvertently give the weight of one of their other children, Weintraub says. "Stressful moments such as those in the ED are not the best times to have accurate recall," she says.

At Harborview Medical Center in Seattle, the ED uses order sheets with a space clearly marked for the child’s weight. "Orders cannot be filled if this is not completed," says Patricia Nora, MSN, ARNP, the facility’s pediatric clinical educator.

• Record weights only in kilograms. Medication dosages always are given on a per-kilogram basis, but weights for children often are recorded in pounds, says Weintraub. "Often, the health care provider documenting the weight does not specify pounds or kilograms, and medication is then ordered at too high a dosage," she says. If the child is unable to be weighed due to his or her condition, and the parent gives a stated weight in pounds, it should be converted to kilograms and only the kilograms recorded on the chart, she advises.

• Use color-coded tape. Every ED should have a Broselow Pediatric Emergency Tape, which estimates the child’s weight to determine drug dosages, or another evidence-based measure to accurately estimate a weight in children, says Weintraub. (See ordering information in "Resources" at the end of this article.)

• Double-check all narcotics. Pain medication is needed for suspected fractures in the right leg of a 10-year-old boy who was hit by a car while riding his bike. The child weighs 28 kg. The order reads "MSO4 2.8 mg q 4 hrs/prn pain." The standard MSO4 concentration is 10 mg/mL. The nurse draws up 2.8 mg of MSO4 and checks the dose with another nurse. The second nurse points out that the calculation is correct, but the concentration is 10 mg/ mL, so the correct dose is only .28 mg of MSO4. "The second nurse has caught a mistake that would have delivered 10 times as much MSO4 to this child," says Nora.

ED nurses at her facility always double-check narcotics and large volume infusions with two nurses, she says. In addition, emergency drug sheets are calculated and printed out for each patient, and these are attached to the end of the bed, says Nora.

Medications with small error margins such as insulin, with increased potential for airway compromise, or highly toxic medications should have the dose double-checked in several ways, says Weintraub. Here are her recommendations:

— The physician should order the medication on the chart and show his/her calculations (for example, morphine 0.1 mg/kg × 12 kg = 1.2 mg).

— The primary nurse should compute and document the calculation as to the dose as well as the volume to be administered (for example, morphine 0.1 mg/kg × 12 kg = 1.2 mg. 1 cc/10 mg × 1.2 mg = .12 cc volume to be delivered).

— A second nurse independently should calculate the dose and volume of medication to be administered and document the calculations.

• Use order forms with specific dosages listed. Harborview’s ED uses a form that lists specific dosages for children admitted from the ED. "This is another safeguard for residents who are not as familiar with pediatric doses," she explains.

Reference

1. Kozer E, Scolnik D, Macpherson A, et al. Variables associated with medication errors in pediatric emergency medicine. Pediatrics 2002; 110:737-742.

Resources

For more information on pediatric medication errors, contact:

Patricia Nora, MSN, ARNP, Pediatric Clinical Educator, Harborview Medical Center, 325 Ninth Ave, Clinical Education, Box 359733, Seattle, WA 98104. Telephone: (206) 731-4872. Fax: (206) 731-2043. E-mail: pnora@u.washington.edu.

Barbara Weintraub, RN, MPH, MSN, Northwest Community Hospital, 800 W. Central Road, Arlington Heights, IL 60005. Telephone: (847) 618-5432. Fax: (847) 618-4169. E-mail: bweintraub@nch.org.

The Broselow Pediatric Emergency Tape is available in a new 2002 edition that reflects the latest guidelines from the American Heart Association. A reference at each weight zone on the tape shows pre-calculated medication dosages and infusion rates. Designated resuscitation equipment is contained in corresponding, color-coded equipment pouches (not included). A package of five tapes is available for $120 (product No. AE4800). To order, contact:

Armstrong Medical Industries, 575 Knightsbridge Parkway, P.O. Box 700, Lincolnshire, IL 60069-0700. Telephone: (800) 323-4220 or (847) 913-0101. Fax: (847) 913-0138. Web: http://armstrongmedical.com.