title: Systematic evaluation of errors occurring during the preparation of intravenous medication.
abstract: BACKGROUND
  Errors in the concentration of intravenous medications are not uncommon. We evaluated steps in the infusion-preparation process to identify factors associated with preventable medication errors.
  
  
  METHODS
  We included 118 health care professionals who would be involved in the preparation of intravenous medication infusions as part of their regular clinical activities. Participants performed 5 infusion-preparation tasks (drug-volume calculation, rounding, volume measurement, dose-volume calculation, mixing) and prepared 4 morphine infusions to specified concentrations. The primary outcome was the occurrence of error (deviation of > 5% for volume measurement and > 10% for other measures). The secondary outcome was the magnitude of error.
  
  
  RESULTS
  Participants performed 1180 drug-volume calculations, 1180 rounding calculations and made 1767 syringe-volume measurements, and they prepared 464 morphine infusions. We detected errors in 58 (4.9%, 95% confidence interval [CI] 3.7% to 6.2%) drug-volume calculations, 30 (2.5%, 95% CI 1.6% to 3.4%) rounding calculations and 29 (1.6%, 95% CI 1.1% to 2.2%) volume measurements. We found 7 errors (1.6%, 95% CI 0.4% to 2.7%) in drug mixing. Of the 464 infusion preparations, 161 (34.7%, 95% CI 30.4% to 39%) contained concentration errors. Calculator use was associated with fewer errors in dose-volume calculations (4% v. 10%, p = 0.001). Four factors were positively associated with the occurrence of a concentration error: fewer infusions prepared in the previous week (p = 0.007), increased number of years of professional experience (p = 0.01), the use of the more concentrated stock solution (p < 0.001) and the preparation of smaller dose volumes (p < 0.001). Larger magnitude errors were associated with fewer hours of sleep in the previous 24 hours (p = 0.02), the use of more concentrated solutions (p < 0.001) and preparation of smaller infusion doses (p < 0.001).
  
  
  CONCLUSIONS
  Our data suggest that the reduction of provider fatigue and production of pediatric-strength solutions or industry-prepared infusions may reduce medication errors.
authors.affiliation: Department of Critical Care Medicine, and the Center for Safety Research, Child Health Evaluative Sciences Program, the Research Institute, The Hospital for Sick Children, Toronto, Ont. christopher.parshuram@sickkids.ca
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Parshuram
authors.forename: Teresa
authors.initials: T
authors.lastname: To
authors.forename: Winnie
authors.initials: W
authors.lastname: Seto
authors.forename: Angela
authors.initials: A
authors.lastname: Trope
authors.forename: Gideon
authors.initials: G
authors.lastname: Koren
authors.forename: Andreas
authors.initials: A
authors.lastname: Laupacis
mesh_terms: D000704:Analysis of Variance; D016009:Chi-Square Distribution; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007262:Infusions, Intravenous; D008508:Medication Errors; D009020:Morphine / Q000008:administration & dosage*; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D009020:Morphine