How many hospital pharmacy medication dispensing errors go undetected?
BACKGROUND
Hospital pharmacies dispense large numbers of medication doses for hospitalized patients. A study was conducted at an academic tertiary care hospital to characterize the incidence and severity of medication dispensing errors in a hospital pharmacy.


METHODS
Direct observation of dispensing processes was undertaken to determine presence of errors with review by a physician panel to determine severity.


RESULTS
A total of 140,755 medication doses filled by pharmacy technicians were observed during a seven-month period, and 3.6% (5075) contalned errors. The hospital pharmacist detected only 79% of these errors during routine verification; thus, 0.75% of doses filled would have left the phannacy with undetected errors. Overall, 23.5% of undetected errors were potential adverse drug events (ADEs), of which 28% were serious and 0.8% were life threatening. The most common potential ADEs were incorrect medications (36%), incorrect strength (35%), and incorrect dosage form (21%).


CONCLUSIONS
Given the volume of medications dispensed, even a low rate of drug distribution process translates into a large number of errors with potential to harm patients. Pharmacy distribution systems require further process redesign to achieve the highest possible level of safety and reliability.
Brigham and Women's Hospital, Boston, USA. jcina@partners.org
Jennifer L
JL
Cina
Tejal K
TK
Gandhi
William
W
Churchill
John
J
Fanikos
Michelle
M
McCrea
Patricia
P
Mitton
Jeffrey M
JM
Rothschild
Erica
E
Featherstone
Carol
C
Keohane
David W
DW
Bates
Eric G
EG
Poon
D000046:Academic Medical Centers; D001900:Boston; D006801:Humans; D007049:Iatrogenic Disease / Q000453:epidemiology; D015994:Incidence; D008485:Medical Audit; D008508:Medication Errors / Q000145:classification / Q000517:prevention & control / Q000706:statistics & numerical data*; D008510:Medication Systems, Hospital / Q000592:standards*; D010607:Pharmacy Service, Hospital / Q000592:standards* / Q000706:statistics & numerical data; D017064:Process Assessment, Health Care; D017751:Safety Management; D013647:Task Performance and Analysis