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.
Cina
Jennifer L
JL
Brigham and Women's Hospital, Boston, USA. jcina@partners.org
Gandhi
Tejal K
TK
Churchill
William
W
Fanikos
John
J
McCrea
Michelle
M
Mitton
Patricia
P
Rothschild
Jeffrey M
JM
Featherstone
Erica
E
Keohane
Carol
C
Bates
David W
DW
Poon
Eric G
EG
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