Retrospective analysis of the frequency and recognition of adverse drug reactions by means of automatically recorded laboratory signals

Aims To estimate the frequency of adverse drug reactions (ADRs) identified through the use of automatic signals generated from laboratory data (ALS) i n hospitalised patients. To determine the frequency of spontaneous recognit ion of these ADRs by the attending physicians and to assess the potential v alue of ALS for detection of ADRs. Methods Laboratory results of patients hospitalised in a nine bed medical w ard were automatically recorded over a period of 17 months. Values exceedin g defined boundaries were used as ALS. Charts of every third patient were a nalysed retrospectively with regard to adverse drug related reactions and c ausality was evaluated as well as whether the ADR had been recognised durin g the period of hospitalisation. Results The charts and ALS of 98 patients were analysed. In 18 cases a drug -related adverse reaction was probable. Awareness to the reaction by the tr eating physicians was evident in 6 out of these 18 ADRs. Approximately 80% of the ADRs were considered predictable. Three ADRs were regarded as seriou s. Conclusions Adverse drug reactions are common and often preventable. Only o ne third of ADRs which could have been detected through ALS were recognised by the attending physicians. An increased doctor's awareness of the freque ncy of drug related abnormal laboratory results by means of ALS is likely t o increase the recognition rate of ADRs and might help to prevent them.