Clinical audit:: a tool to monitor pre-analytical errors in the laboratory

The aim of this study was to evaluate the effectiveness of a clinical audit program to monitor and reduce the magnitude of pre-analytical errors in the Emergency Laboratory of a Buenos Aires Province public hospital. During a 2004 period and another 2005 one, different types of errors were surveyed in 11.949 blood- and urine-sample flasks. The following indicators were calculated: sample pre-analytical error percentage (% PE), as well as percentages corresponding to coagulated samples, inadequate flask use, inadequate flask volume, samples that underwent haemolysis, shaken samples and poor sample identification. Nursing personnel were trained. Costs incurred were allocated to the extraction and delivery stages within the pre-analytical phase. PE % did not show any meaningful changes in 2004, while in 2005 its variations followed those of some of the other indicators. Costs attributed to pre-analytical error represented 10% of total cost of sample extraction and delivery in the periods that were studied. It can be concluded that training courses must be periodically offered and their results monitored on a permanent basis if any significant and long-lasting reduction in the magnitude of pre-analytical errors is to be achieved.