Objectives: To investigate the incidence and the severity of intravenous (i.v.) drug preparation and administration errors in two countries and three pharmacy services.
Method: A disguised observational method was used to record details of the preparation and administration of prescribed i.v. drugs on two wards in each of three teaching hospitals: one with a traditional British ward pharmacy service (TBP) and two hospitals in Germany, one with a traditional ward stock supply (TGP) and one with a satellite pharmacy service (GSP) with unit dose system.
Main outcome measures: Errors in i.v. drug preparation and administration and their potential significance.
Results: The number of observed preparations/administrations were: TBP 77/63, TGP 126/109 and GSP 134/106. The preparation error rates were: TBP 22% (95% confidence interval: 13-31%), TGP 23% (16-30%) and GSP 31% (23-39%). The administration error rates were TBP 27% (16-38%), TGP 49% (39-58%) and GSP 22% (14-30%). The percentage of administration errors on the wards with TGP was statistically significantly higher than in the other two services. Common errors at the study sites with TBP and GSP were omissions. Wrong rate of administration occurred most frequently on the wards with TGP. The majority of errors were likely to be of 'moderate' to 'severe' outcome. Careful drug chart reading could possibly reduce omission errors on the wards with TBP. A change of the German nursing law ('Krankenpflegegesetz') to legally entitle nurses to administer i.v. drugs could probably result in better training, national guidelines and standards.
Conclusion: This study found a high rate of i.v. medication errors of moderate to severe significance. Changes in practice should be considered to make i.v. therapy safer for patients.