Fourteen potassium results, one overridden control

You are reviewing an autoverification queue on the core chemistry bench, day shift. Potassium results on 14 specimens run between 08:00 and 09:05 are sitting 0.3 to 0.6 mmol/L higher than delta-check history would predict for those patients. All 14 were internally released by autoverification before the hold; 3 of those results were already reported to ordering clinicians, while 11 were contained inside the laboratory.

You pull the QC log and find the 08:00 level 2 liquid QC result for potassium was 5.9 mmol/L against a target of 4.5 mmol/L, with a 2 SD range of 4.2 to 4.8 mmol/L. That is a QC failure. It was overridden, and patient testing resumed without an investigation. The distinction matters: internal release/autoverification is not the same as reporting a result to a clinician.

Nothing here is a diagnosis. A falsely elevated potassium (hyperkalemia) result carries real clinical weight: it can prompt unnecessary treatment, extra monitoring, or a repeat blood draw before anyone confirms whether the number is real. The bench question is not why the QC failed yet. The bench question is: what do you do in the next five minutes, and what do you write down before you try to explain it.

A nonconforming event (NCE) is an occurrence that does not conform to the laboratory's own policies or procedures, does not meet applicable regulatory or accreditation requirements, or has affected or could affect patient, donor, or personnel safety.

An overridden QC failure followed by patient release is a nonconforming event the moment it is recognized, regardless of whether the result is ever confirmed inaccurate.