Analytical interference of intravascular contrast agents with clinical laboratory tests: a joint guideline by the ESUR Contrast Media Safety Committee and the Preanalytical Phase Working Group of the EFLM Science Committee

The Contrast Media Safety Committee of the European Society of Urogenital Radiology has, together with the Preanalytical Phase Working Group of the EFLM Science Committee, reviewed the literature and updated its recommendations to increase awareness and provide insight into these interferences.

Blood alcohol concentration in the clinical laboratory: a narrative review of the preanalytical phase in diagnostic and forensic testing

The analysis of blood alcohol concentration (BAC), a pivotal toxicological test, concerns acute alcohol intoxication (AAI) and driving under the influence (DUI). As such, BAC presents an organizational challenge for clinical laboratories, with unique complexities due to the need for forensic defensibility as part of the diagnostic process. Unfortunately, a significant number of scientific investigations dealing with the subject present discrepancies that make it difficult to identify optimal practices in sample collection, transportation, handling, and preparation. This review provides a systematic analysis of the preanalytical phase of BAC that aims to identify and explain the chemical, physiological, and pharmacological mechanisms underlying controllable operational factors. Nevertheless, it seeks evidence for the necessity to separate preanalytical processes for diagnostic and forensic BAC testing. In this regard, the main finding of this review is that no literature evidence supports the necessity to differentiate preanalytical procedures for AAI and DUI, except for the traceability throughout the chain of custody. In fact, adhering to correct preanalytical procedures provided by official bodies such as European federation of clinical chemistry and laboratory medicine for routine phlebotomy ensures both diagnostic accuracy and forensic defensibility of BAC. This is shown to depend on the capability of modern pre-evacuated sterile collection tubes to control major factors influencing BAC, namely non-enzymatic oxidation and microbial contamination. While certain restrictions become obsolete with such devices, as the use of sodium fluoride (NaF) for specific preservation of forensic BAC, this review reinforces the recommendation to use non-alcoholic disinfectants as a means to achieve "error-proof" procedures in challenging operational environments like the emergency department.

Quality of hematology and clinical chemistry results in laboratory and zoo nonhuman primates: Effects of the preanalytical phase. A review

Most errors in clinical pathology originate in the preanalytical phase, which includes all steps from the preparation of animals and equipment to the collection of the specimen and its management until analyzed. Blood is the most common specimen collected in nonhuman primates. Other specimens collected include urine, saliva, feces, and hair. The primary concern is the variability of blood hematology and biochemistry results due to sampling conditions with the effects of capture, restraint, and/or anesthesia. Housing and diet have fewer effects, with the exception of food restriction to reduce obesity. There has been less investigation regarding the impact of sampling conditions of nonblood specimens.

Recommendation for the design of stability studies on clinical specimens

OBJECTIVES

Knowledge of the stability of analytes in clinical specimens is a prerequisite for proper transport and preservation of samples to avoid laboratory errors. The new version of ISO 15189:2022 and the European directive 2017/746 increase the requirements on this topic for manufacturers and laboratories. Within the project to generate a stability database of European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group Preanalytical Phase (WG-PRE), the need to standardise and improve the quality of published stability studies has been detected, being a manifest deficit the absence of international guidelines for the performance of stability studies on clinical specimens.

METHODS

These recommendations have been developed and summarised by consensus of the WG-PRE and are intended primarily to improve the quality of sample stability claims included in information for users provided by assay supplier companies, according to the requirements of the new European regulations and standards for accreditation.

RESULTS

This document provides general recommendations for the performance of stability studies, oriented to the estimation of instability equations in the usual working conditions, allowing flexible adaptation of the maximum permissible error specifications to obtain stability limits adapted to the intended use.

CONCLUSIONS

We present this recommendation based on the opinions of the EFLM WG-PRE group for the standardisation and improvement of stability studies, with the intention to improve the quality of the studies and the transferability of their results to laboratories.

Taking a step back from testing: Preanalytical considerations in molecular infectious disease diagnostics

Recent studies evaluating the preanalytical factors that impact the outcome of nucleic-acid based methods for the confirmation of SARS-CoV-2 have illuminated the importance of identifying variables that promoted accurate testing, while using scarce resources efficiently. The majority of laboratory errors occur in the preanalytical phase. While there are many resources identifying and describing mechanisms for main laboratory testing on automated platforms, there are fewer comprehensive resources for understanding important preanalytical and environmental factors that affect accurate molecular diagnostic testing of infectious diseases. This review identifies evidence-based factors that have been documented to impact the outcome of nucleic acid-based molecular techniques for the diagnosis of infectious diseases.

Development of a virtual classroom for pre-analytical phase of laboratory medicine for undergraduate medical students using the Delphi technique

Background

Amongst the pre-analytical, analytical, and post-analytical phase of laboratory testing, pre-analytical phase is the most error-prone. Knowledge gaps in understanding of pre-analytical factors are identified in the clinical years amongst undergraduate students due to lack of formal teaching modules on the pre-analytical phase. This study was conducted to seek experts’ consensus in Clinical Chemistry on learning objectives and contents using the Delphi technique with an aim to develop an asynchronous virtual classroom for teaching pre-analytical factors of laboratory testing.

Methods

A mixed method study was conducted at the Aga Khan University. A questionnaire comprising of 16 learning objectives and their associated triggers was developed on Google Docs for developing the case vignettes. A four-point Likert Scale, which included strongly agree, agree, disagree and strongly disagree, was utilized for the learning objectives. An open-ended question was included for experts to suggest new items for inclusion. A cut off of at least 75% agreement was set to establish consensus on each item. A total of 17 Chemical Pathology faculty from 13 institutions across Pakistan were invited to participate in the first round of Delphi. Similar method of response was used in round two to establish consensus on the newly identified items suggested by the faculty in round 1. Later, the agreed-upon objectives and triggers were used to develop interactive scenarios over Moodle to concurrently test and teach medical students in a nonchalant manner.

Results

A total of 17 responses were received in Round 1 of the Delphi process (response rate = 100%), while 12 responses were received in Round 2 (response rate = 71%). In round 1, all 16 learning objectives reached the required consensus (≥ 75%) with no additional learning objectives suggested by the experts. Out of 75 triggers in round 1, 61 (81.3%) reached the consensus to be included while 39 were additionally suggested. In 2nd round, 17 out of 39 newly suggested triggers met the desired consensus. 14 triggers did not reach the consensus after two rounds, and were therefore eliminated. The virtual classroom developed using the agreed-upon learning objectives and triggers consisted of 20 items with a total score of 31 marks. The questions included multiple choice questions, fill in the blanks, drag and drop sequences and read-and-answer comprehensions. Specific learning points were included after each item and graphs and pictures were included for a vibrant experience.

Conclusion

We developed an effective and interactive virtual session with expert consensus on the pre-analytical phase of laboratory testing for undergraduate medical students which can be used for medical technologist, graduate students and fellows in Chemical Pathology.

Types and Frequency of Errors in the Pre-Analytical Phase in the Clinical Laboratory - Single Center Study from Bosnia and Herzegovina

BACKGROUND

The pre-analytical phase, which includes all preparatory actions to the analytical procedure, is part of the process during which there is the greatest possibility of laboratory errors. This study was conducted to investigate the frequency and types of laboratory errors during work in the clinical laboratory as well as the frequency and types of laboratory errors in the pre-analytical phase of laboratory work.

METHODS

The retrospective, descriptive study covered the period from 01/01/2016 to 12/31/2016 within which the presence of 5 different indicators of quality of work, i.e., pre-analytical errors, was monitored: improperly drawn blood, coagulated blood sample, hemolyzed blood sample, improperly marked referral for analysis, and insufficient sample for analysis.

RESULTS

The most common error in the pre-analytical phase of our study was "coagulated sample", followed by: "improperly drawn blood", "improperly marked referral", "insufficient sample for analysis", and "hemolyzed sample". Using the chi-squared test, a statistically significant difference was found in the frequency of occurrence of certain types of indicators in different departments (p < 0.005).

CONCLUSIONS

Reduction of these errors can be achieved through analyzing and correcting the reasons for them, education, and by joint action of experts and international organizations, continual training of staff as well as to following the adopted guidelines and standards.

Pre-Analytical Error Cost Analysis of 10,732 Contaminated Urine Culture Samples

BACKGROUND

Unlike other pre-analytical (PA) phase errors, in our country Social Security Institution (SSI) reimburses urine samples rejected due to contamination in the form of a finalized test. The primary purpose was to estimate the direct financial loss created by contaminated urine sampling. We want to encourage its prioritization among corrective and preventive actions of laboratory PA management.

METHODS

We examined the urine samples which were sent to Istanbul Anatolian North Central Laboratory retrospectively. The central laboratory serves the community of 6,400-bed hospitals. We made direct financial loss calculations with material-, labor-, and waste-related financial elements.

RESULTS

We rejected 10,732 of 138,834 samples due to contamination. With the 2019 Euro Index, the cost for each urine sample rejected due to contamination was calculated as € 2.98.

CONCLUSIONS

It is the first cost study where the prices are in human resources, material, waste cost, and the amount reimbursed by SSI as direct cost elements per rejection sample. Highlighting the cost elements in establishing health policies predicted due to their striking feature may contribute to their prioritization in corrective and preventive actions. The urine culture test is the most commonly performed bacterial culture test. The determination of financial loss predicted that it would also reduce antibiotic resistance in healthcare by providing financial resource threshold information to develop improved methods. In addition, it will inspire new additions to the existing few detailed pre-analytical error cost studies.

Medical Staff Training - Quality Initiative to Reduce Errors in the Pre-Preanalytical Phase

BACKGROUND

Numerous studies indicate that most error sources in hemostasis laboratories occur during the pre preanalytical phase through biological product sampling.

OBJECTIVES

The purpose of this study was documentation, monitoring, and reduction of preanalytical errors through operator training.

METHODS

For a period of 4 months in the "St. Spiridonˮ Hospital from Iaşi, 978 specimens were identified with non-conformities, due to the following causes: insufficiently-collected, hemolyzed- and coagulated samples. Data collection was conducted in two stages: before and after training of medical staff in clinical departments, upon improving the coagulation specimen sampling practices.

RESULTS

The study pointed out that subsequent to training, a reduction of the coagulated samples has been registered as follows: in medical departments from 33.33% to 16.78%, in surgery from 27.20% to 17.02%, ICU (intensive care units) from 10.63% to 8.74%, and slightly in EU (emergency) from 10.63% to 8.74%. Moreover, we noticed that the incidence of hemolyzed samples increased in clinical sections, as follows: EU from 4.50% to 14.89%, medical departments from 3.42% to 9.21%, surgery from 1.44% to 6.38%, and 4.50% to 14.89% for ICU. The insufficiently sampled volume persisted during the study in almost all sections: surgery from 1.80% to 4.96%, medical from 2.52% to 4.96%, EU from 1.80% to 3.78% with a slight decrease in ICU from 1.26% to 1.18%.

CONCLUSIONS

Nurses traditionally represent the core of quality medical services. Peer education is effective and implementation and compliance of sample collection procedure rules ultimately providing patient safety.

Vitamin C measurement in critical illness: challenges, methodologies and quality improvements

Background There is renewed interest in high-dose vitamin C interventions in clinical medicine due to its antioxidant properties, safe use and cost-effectiveness. Yet, randomised control trials (RCTs) employing these interventions are failing to include robust analytical methodology and proper sample handling and processing techniques. Consequently, comparisons between studies becomes impossible as there is no metrological traceability and results may be prone to pre-analytical errors. Content Through published vitamin C stability studies, method comparison papers and data from vitamin C external quality assurance programs, an assessment was made on the functionality of current methods for critically ill patient samples. Summary Data was obtained from two external quality assurance programs, two papers assessing sample stability and interlaboratory agreement and a publication on vitamin C method comparisons. A shift from spectrophotometric and enzymatic methodologies to high performance liquid chromatography (HPLC) greatly improved the variability and interlaboratory agreement. Therefore, the current analytical performance of vitamin C HPLC methodologies are acceptable for the requirements of a high-dose vitamin C RCTs. Outlook Recommendations across the total testing process of vitamin C have been provided to improve the quality of the results. The harmonisation of sample handling and processing procedures will further improve the reliability of current analytical methodologies.

Defining and Managing the Preanalytical Phase With FMECA: Automation and/or "Human" Control

OBJECTIVE

Our scope is to provide methodological elements on how to manage effectively the preanalytical phase in the laboratory testing process, by objectively measuring the risk connected to the phases handled by man with respect to those managed by machines.

BACKGROUND

Preanalytical errors account for most of the mistakes related to laboratory testing and can affect patient care. Hence, it is necessary to manage the risk connected to the preanalytical phase, as required by certification and accreditation bodies. The risk assessment discloses the steps at greater risk and gives indications to make decisions.

METHOD

We have reviewed the state of art in the automation of the preanalytical phase, addressing needs and problems. We have used the proactive risk assessment methodology FMECA (Failure Mode, Effects, and Criticality Analysis) to identify the most critical phases in our preanalytical process and have calculated the risk associated.

RESULTS

The most critical phases were the human controlled ones. In particular, the highest risk indexes were associated to manual acceptance of test orders, identification of the patients, tube labeling, and sample collection.

CONCLUSION

Automation in the preanalytical phase is fundamental to replace, support, or extend the human contribution. Nevertheless each organization is different about workloads and competencies, so the most suitable management must be tailor-made in each context.

APPLICATION

We present a method by which each organization is able to find its best balance between automation and human contribution in the control of the preanalytical phase.

Novel bone metabolism-associated hormones: the importance of the pre-analytical phase for understanding their physiological roles

The endocrine function of bone is now a recognized feature of this tissue. Bone-derived hormones that modulate whole-body homeostasis, are being discovered as for the effects on bone of novel and classic hormones produced by other tissues become known. Often, however, the data regarding these last generation bone-derived or bone-targeting hormones do not give about a clear picture of their physiological roles or concentration ranges. A certain degree of uncertainty could stem from differences in the pre-analytical management of biological samples. The pre-analytical phase comprises a series of decisions and actions (i.e., choice of sample matrix, methods of collection, transportation, treatment and storage) preceding analysis. Errors arising in this phase will inevitably be carried over to the analytical phase where they can reduce the measurement accuracy, ultimately, leading discrepant results. While the pre-analytical phase is all important, in routine laboratory medicine, it is often not given due consideration in research and clinical trials. This is particularly true for novel molecules, such as the hormones regulating the endocrine function of bone. In this review we discuss the importance of the pre-analytical variables affecting the measurement of last generation bone-associated hormones and describe their, often debated and rarely clear physiological roles.