Pre-analytical errors in coagulation testing: a case series.

Objectives: Prevention of pre-analytical issues in coagulation testing is of paramount importance for good laboratory performance. In addition to common issues like hemolysed, icteric, or lipemic samples, some specific pre-analytical errors of coagulation testing include clotted specimens, improper blood-to-anticoagulant ratio, contamination with other anticoagulants, etc. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) are very commonly affected tests due to pre-analytical variables. The impact these parameters possess on surgical decision-making and various life-saving interventions are substantial therefore we cannot afford laxity and casual mistakes in carrying out these critical investigations at all.

Case presentation: In this case series, a total of 4 cases of unexpectedly deranged coagulation profiles have been described which were reported incorrectly due to the overall casual approach towards these critical investigations. We have also mentioned how the treating clinician and lab physician retrospectively accessed relevant information in the nick of time to bring back reassurance.

Conclusions: Like every other critical investigation, analytical errors can occur in coagulation parameters due to various avoidable pre-analytical variables. The release of spurious results for coagulation parameters sets alarm bells ringing causing much agony to the treating doctor and patient. Only a disciplined and careful approach taken by hospital and lab staff towards each sample regardless of its criticality can negate these stressful errors to a large extent.