Improving the safety of intravenous admixtures: lessons learned from a Pentostam overdose

Weaknesses in the multistep process of admixture preparation and administration resulted in a patient with cutaneous leishmaniasis (CL) receiving a 10-fold intravenous (IV) overdose of Pentostam (sodium stibogluconalte), a rarely used drug.

A review of this adverse event resulted in five recommendations: (1) Provide staffing continuity among pharmacists and pharmacy technicians preparing and nurses administering the admixture; (2) Take time to ensure thorough and deliberative consideration ofquestions or concerns about admixture preparation; (3) Use due diligence in performing double checks of admixture calculations; (4) Know the drug and seek clarification when appropriate; and (5) Examine label information carefully. PROGRESS UPDATE: Two changes were made to improve patientsafety. First, a form was developed to accompany the preparation of complex IV drugs, including chemoltherapy solutions and nonformulary IV admixtures; the form is consistently used. Second, the pharmacy service developed information sheets for 12 high-risk drugs frequently used in IV admixtures.

The medical center had processes in place to prevent medication errors, yet an error occurred nonetheless. Weaknesses were identified in staff communication, quality assurance checks, and product labeling. Also, nurses and pharmacists had less than adequate information about new or unusually dosed medications.