Wrong MRN on a Barcode Label
A 58-year-old inpatient, Mr A, has a fasting glucose of 5.8 mmol/L and an HbA1c of 6.1%. A 71-year-old inpatient, Mr B, has the same surname and was admitted on the same day with confusion; his capillary glucose is 2.9 mmol/L, a critical low value. A new registration clerk creates a barcode label for Mr B’s EDTA tube but accidentally selects Mr A’s medical record number (MRN) from the dropdown list. The label is applied, the sample is analysed, and the analyser interface files the results under Mr A’s MRN. The laboratory information system (LIS) generates a critical-value alert for Mr A: glucose 2.9 mmol/L. The technician notices that Mr A’s chart has no hypoglycaemia symptoms and that Mr B’s result is missing.
1. What is the immediate patient-safety risk, and what must the technician do before telephoning the critical result?
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The risk is a wrong-patient result: Mr A may receive unnecessary glucose treatment, while Mr B’s true hypoglycaemia is missed. Before phoning, the technician must stop and verify identity using two identifiers: full name, date of birth, and MRN on the tube label, request form, and LIS record. Check whether the barcode was generated at collection or pre-printed. Do not release or phone the result until the mismatch is confirmed. Then collect a fresh sample from Mr B and repeat the glucose urgently; notify the supervisor and the clinical team immediately.
2. Identify the root causes and the immediate corrective actions.
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Root causes include selection of the wrong MRN at registration, label application away from the patient, no bedside identity check, and interface filing by MRN without a name/date-of-birth mismatch check. Immediate actions: quarantine or correct the result in the LIS with an audit trail; inform both clinical teams; repeat glucose on both patients; document the incident; and review other results entered under the same MRN during the shift. Do not simply delete the result; use the LIS error-correction workflow so the original entry remains traceable.
3. What LIS or barcode controls would prevent recurrence?
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Use positive patient identification at the bedside: scan the wristband and the label at collection, with a hard stop if name, date of birth, and MRN do not match. Print labels only at the point of collection, never in advance. Configure the interface to reject results when the MRN and patient name/date of birth do not match, and to flag duplicate or same-surname admissions. Add a critical-value callback screen that displays two identifiers. Restrict MRN dropdown access and require a scan or search by at least two fields. Audit registration errors and train staff.