PATIENT MIX-UP DUE TO PRE-LABELLING OF SPECIMEN TUBES PRIOR TO SAMPLE COLLECTION

Abstract

The Universitas Hospital NHLS Laboratory received a query from a paediatrician regarding the “delayed” laboratory results for baby H, a 1-month-old infant. The laboratory had received nine specimens from that same unit but none for baby H. Upon investigation, using standard laboratory procedures of checking traceability and delta-checking of consecutive chemistry test results over a few days, results were found for a baby whose blood had not been sampled that day (baby M). Review of baby M’s results appeared to better match the clinical findings of baby H mainly because he was jaundiced (on phototherapy) and baby H was not. A further complication was that 10 sample collection tubes had been pre-labelled in preparation for the phlebotomy procedure. However, because blood had not been collected from baby M there was the added possibility of a serial error in sample-patient linking in 8 of the remaining 9 samples. Most laboratory errors occur in the pre-analytical phase, and many of these involve mislabelling of specimen tubes. Morning group pre-labelling is a common Universitas hospital practice prior to actual phlebotomy and is designed to speed up the sample collection process, so that results are available in time for the morning consultant ward round. This report serves to act as an alert of the possible dangers of serial error and possible disastrous effect on patient care.