The impact of computerised physician order entry on prescribing practices in a cardiothoracic intensive care unit.

This prospective, time series, cross-sectional study was designed to compare the quality of handwritten vs computerised prescriptions in a tertiary 25-bedded cardiothoracic intensive care unit. A total of 14,721 prescriptions for 613 patients were analysed over three periods of investigation: 7 months before; and 5 and 12 months after implementation of a clinical information system with computerised physician order entry capability. Errors in prescribing were common. Only (53%) of handwritten charts analysed had all immediate administration drugs prescribed correctly. Errors included omission of route 81 (8.0%), date of prescription 78 (7.7%), and time to be given 255 (25.2%), and 119 (11.7%) had no dose or an incorrect dose prescribed. All errors of completeness were abolished following implementation. The computerised system led to a significant improvement in prescribing safety, in a clinical area previously highlighted as having a high rate of adverse drug errors. Legibility, completeness and traceability are no longer possible sources of medication errors.