Recommendations for detection and management of unsuitable samples in clinical laboratories

Abstract

A large body of evidence attests that quality programs developed around the analytical phase of the total testing process would only produce limited improvements, since the large majority of errors encountered in clinical laboratories still prevails within extra-analytical areas of testing, especially in manually intensive preanalytical processes. Most preanalytical errors result from system flaws and insufficient audit of the operators involved in specimen collection and handling responsibilities, leading to an unacceptable number of unsuitable specimens due to misidentification, in vitro hemolysis, clotting, inappropriate volume, wrong container or contamination from infusive routes. Detection and management of unsuitable samples are necessary to overcome this variability. The present document, issued by the Italian Inter-society SIBioC-SIMeL-CISMEL (Society of Clinical Biochemistry and Clinical Molecular Biology-Italian Society of Laboratory Medicine-Italian Committee for Standardization of Hematological and Laboratory Methods) Study Group on Extra-analytical Variability, reviews the major causes of unsuitable specimens in clinical laboratories, providing consensus recommendations for detection and management.

Preanalytical quality improvement. In pursuit of harmony, on behalf of European Federation for Clinical Chemistry and Laboratory Medicine (EFLM) Working group for Preanalytical Phase (WG-PRE)

“…Instead of being evidence based, those criteria are unfortunately quite often based on manufacturer's declarations, expert opinion or historical reasons. They are only limited examples of sharing acceptance criteria on a national basis [87,88]. Therefore, the crucial question is to establish whether those criteria are correct or not, and if they really fit for the purpose.…”

Preanalytical quality improvement: from dream to reality

“…Additional problems include inappropriate storage conditions during transportation and inappropriate procedures for sample preparation before analysis (e.g., refrigeration, time delay before analysis, centrifuging conditions). In agreement with the foremost model of human errors of the Swiss cheese model, where defensive layers (slice of cheese) have a number of vulnerabilities (holes) that are continually opening, shutting and shifting their location, leaving the opportunity for a trajectory of accident opportunity that may irreversibly penetrate the barrier, the most reliable and effective approach for limiting the impact of preanalytical variability is the implementation of a multifaceted strategy, encompassing the adoption of a wide series of diversified defensive layers that would limit the eventuality of any adverse event of occurring (8,10,18). As such, full implementation of risk management and total quality system is mandatory, through a strategic approach which would include a foremost policy for prediction of accidental events (i.e., process analysis, reassessment and rearrangement of quality requirements, dissemination of operative guidelines and best-practice recommendations for sample collection and management, reduction of complexity in error-prone activities, introduction of error-tracking systems and continuous monitoring of performances), increase and diversification of defences (application of multiple and heterogeneous systems to identify unsuitable specimens), and decrease vulnerability (implementation of reliable and objective detection systems and causal relation charts, education and training).…”

Multicenter evaluation of the hemolysis index in automated clinical chemistry systems

“…Finally, the automated HI allows standardization and harmonization of behavior among operators in the same laboratory or among different facilities. Although widespread implementation of this technology is thus advantageous, advisable and even recommended (7,9), there are no reports, to the best of our knowledge, that have compared the efficiency of different analytical platforms for the identification and correct classification of hemolyzed specimens.…”