Comparison of a two-step Tempus600 hub solution single-tube vs. container-based, one-step pneumatic transport system

OBJECTIVES

Efficient and timely transportation of clinical samples is pivotal to ensure accurate diagnoses and effective patient care. During the transportation process, preservation of sample integrity is crucial to avoid pre-analytical aberrations on laboratory results. Here, we present a comparative analysis between a two-step Tempus600 hub solution single-tube and a one-step, container-based pneumatic transport system (PTS) from Airco, for the in-house transportation of blood samples.

METHODS

Ten blood samples from healthy volunteers were split in 10 mL collection tubes filled at full or half capacity for transportation with the two PTS (about 250 m). To compare the impact of transportation, markers of hemolysis such as lactate dehydrogenase (LDH), potassium (K+), and the hemolysis index (HI), were determined. Additionally, differences in HI in routine samples and repeated transportation was investigated. To assess and compare the mechanistic impact profiles, we recorded the acceleration profiles of the two PTS using a shock data logger.

RESULTS

Transportation using the Tempus600 hub solution resulted in 49 and 46 % higher HI with samples filled to total or half capacity, respectively. Routine samples transported with the Tempus600 hub solution showed a higher median HI by 23 and 33 %. Additionally, shock logger analysis showed an elevated amount of shocks (6.5 fold) and shock intensities (1.8 fold).

CONCLUSIONS

The Tempus600 hub solution caused an increased number of unreportable LDH or K+ results based on the hemolysis index. However, it was only statistically significant for LDH (p<0.01 and p<0.08) - while the comparisons for K+ were not statistically significant (p<0.28 and p<0.56).

The impact of preanalytical variables on the analysis of cell-free DNA from blood and urine samples

Cell-free DNA (cfDNA), a burgeoning class of molecular biomarkers, has been extensively studied across a variety of biomedical fields. As a key component of liquid biopsy, cfDNA testing is gaining prominence in disease detection and management due to the convenience of sample collection and the abundant wealth of genetic information it provides. However, the broader clinical application of cfDNA is currently impeded by a lack of standardization in the preanalytical procedures for cfDNA analysis. A number of fundamental challenges, including the selection of appropriate preanalytical procedures, prevention of short cfDNA fragment loss, and the validation of various cfDNA measurement methods, remain unaddressed. These existing hurdles lead to difficulties in comparing results and ensuring repeatability, thereby undermining the reliability of cfDNA analysis in clinical settings. This review discusses the crucial preanalytical factors that influence cfDNA analysis outcomes, including sample collection, transportation, temporary storage, processing, extraction, quality control, and long-term storage. The review provides clarification on achievable consensus and offers an analysis of the current issues with the goal of standardizing preanalytical procedures for cfDNA analysis.

Pediatric hemolysis in emergency departments: Prevalence, risk factors, and clinical implications

OBJECTIVE

This study aimed to analyze the prevalence, risk factors, and clinical implications of hemolyzed laboratory samples in the pediatric emergency department (ED), a subject on which existing data remains scarce.

METHODS

We conducted a multi-site observational cohort analysis of pediatric ED encounters in Metro Detroit, Michigan, United States. The study included participants below 18 years of age who had undergone peripheral intravenous catheter (PIVC) placement and laboratory testing. The primary outcome was the presence of hemolysis, and secondary outcomes included identifying risk factors for hemolysis and assessing the impact of hemolysis on PIVC failure.

RESULTS

Between January 2021 and May 2022, 10,462 ED encounters met inclusion criteria, of which 14.0% showed laboratory evidence of hemolysis. The highest proportion of hemolysis occurred in the infant (age 0-1) population (20.1%). Multivariable regression analysis indicated higher odds of hemolysis for PIVCs placed in the hand/wrist in the toddler (age 2-5) and child (age 6-11) subgroups. PIVCs placed in the hand/wrist also demonstrated higher odds of failure in infants.

CONCLUSIONS

Hemolysis in the pediatric ED population is a frequent complication that occurs at similar rates as in adults. PIVCs placed in the hand/wrist were associated with higher odds of hemolysis compared to those placed in the antecubital fossa. Clinicians should consider alternative locations for PIVC placement if clinically appropriate. Further research is needed to better understand the clinical implications of pediatric hemolysis.

Critical Factors in the Analytical Work Flow of Circulating Tumor DNA-Based Molecular Profiling

BACKGROUND

Liquid biopsy testing, especially molecular tumor profiling of circulating tumor DNA (ctDNA) in cell-free plasma, has received increasing interest in recent years as it serves as a reliable alternative for the detection of tumor-specific aberrations to guide treatment decision-making in oncology. Many (commercially available) applications have been developed, however, broad divergences in (pre)analytical work flows and lack of universally applied guidelines impede routine clinical implementation. In this review, critical factors in the blood-based ctDNA liquid biopsy work flow are evaluated.

CONTENT

In the preanalytical phase, several aspects (e.g., blood collection tubes [BCTs], plasma processing, and extraction method) affect the quantity and quality of the circulating cell-free DNA (ccfDNA) applicable for subsequent molecular analyses and should meet certain standards to be applied in diagnostic work flows. Analytical considerations, such as analytical input and choice of assay, might vary based on the clinical application (i.e., screening, primary diagnosis, minimal residual disease [MRD], response monitoring, and resistance identification). In addition to practical procedures, variant interpretation and reporting ctDNA results should be harmonized. Collaborative efforts in (inter)national consortia and societies are essential for the establishment of standard operating procedures (SOPs) in attempts to standardize the plasma-based ctDNA analysis work flow.

SUMMARY

Development of universally applicable guidelines regarding the critical factors in liquid biopsy testing are necessary to pave the way to clinical implementation for routine diagnostics.

Comparison of Clinical, Economic, and Humanistic Outcomes Between Blood Collection Approaches: A Systematic Literature Review

BACKGROUND

A systematic literature review was performed to understand the prevalence, advantages, and disadvantages of blood collection using different approaches (direct venipuncture or vascular access devices), and interventions used to mitigate the disadvantages.

METHODS

The review included a broad range of study designs and outcomes. Database searches (Embase, MEDLINE, Cochrane library, and Centre for Reviews and Dissemination) were conducted in March 2021 and supplemented by hand searching.

RESULTS

One hundred forty-one publications were included. The data indicate that blood sampling from vascular access devices is common in emergency departments, trauma centers, and intensive care units. Studies showed that hemolysis and sample contamination place a considerable economic burden on hospitals. Significant cost savings could be made through enforcing strict aseptic technique, or using the initial specimen diversion technique.

CONCLUSIONS

Hemolysis and sample contamination are far from inevitable in vascular access device-collected or venipuncture samples; both can be reduced through adherence to strict blood sampling protocols and utilization of the initial specimen diversion technique. Needle-free blood collection devices offer further hope for reducing hemolysis. No publication focused on the difficult venous access population; insertion success rates are likely to be lower (and the benefits of vascular access devices higher) in these patients.

Hemolyzed Laboratory Specimens in the Emergency Department: An Underappreciated, but Frequent Problem

INTRODUCTION

Hemolysis of blood samples from emergency department (ED) patients leads to delays in treatment and disposition. The aim of this study is to determine the frequency of hemolysis and variables predictive of hemolysis.

METHODS

This observational cohort study was conducted among three institutions: academic tertiary care center and two suburban community EDs, with an annual census of over 270,000 ED visits. Data were obtained from the electronic health record. Adults requiring laboratory analysis with at least one peripheral intravenous catheter (PIVC) inserted within the ED were eligible. Primary outcome was hemolysis of lab samples and secondary outcomes included variables related to PIVC failure.

RESULTS

Between January 8, 2021 and May 9, 2022, 141,609 patient encounters met inclusion criteria. The average age was 55.5 and 57.5% of patients were female. Hemolysis occurred in 24,359 (17.2%) samples. In a multivariate analysis, when compared to 20-gauge catheters, smaller 22-gauge catheters had an increased odds of hemolysis (OR 1.78, 95% confidence interval (CI) 1.65-1.91; P < .001), while larger 18-gauge catheters had a lower odds of hemolysis (OR 0.94; 95% CI 0.90-0.98; P = .0046). Additionally, when compared to antecubital placement, hand/wrist placement demonstrated increased odds of hemolysis (OR 2.06; 95% CI 1.97-2.15; P < .001). Finally, hemolysis was associated with a higher rate of PIVC failure (OR 1.06; 95%CI 1.00-1.13; P = 0.043).

DISCUSSION

This large observational analysis demonstrates that lab hemolysis of is a frequent occurrence among ED patients. Given the added risk of hemolysis with certain placement variables, clinicians should consider catheter gauge/placement location to avoid hemolysis that may result in patient care delays and prolonged hospital stays.

Reducing blood sample hemolysis in the emergency department using S-Monovette® in aspiration mode

Background

Blood sample hemolysis continues to be a significant problem in clinical practice. In vitro hemolysis rates up to 77% have been reported in literature. The use of manual aspiration techniques for blood sampling has previously been shown to reduce the burden of erythrocyte injury in the pre-analytical phase compared to the vacuum collection technique. This study compares the hemolysis rates between two blood sampling methods: 5.0 ml BD Vacutainer® SST™ (BDV) and 4.9 ml S-Monovette® serum gel tubes in aspiration mode (SMA).

Methods

This was a prospective randomised controlled study conducted in an Emergency department (ED). A convenience sample of 191 adult patients, aged 18-90 years old, presenting at the ED and requiring blood samples for serum electrolyte was included in the study. Paired blood samples were obtained through an intravenous cannula from each patient with randomised order of blood draw using SMA or BDV. Patient data was obtained and hemolysis index (HI), serum lactate dehydrogenase (LDH), and serum potassium (K) levels measured.

Results

The adjusted mean HI (35.2 vs 21.5 mg/dL, p < 0.001), serum K (4.38 vs 4.16 mmol/L, p < 0.001) and LDH levels (259.6 vs 228.4 U/L, p < 0.001) were significantly higher in blood samples taken using BDV compared to SMA. The frequency of severely hemolyzed (>150 mg/dL) samples was also higher in blood collected using BDV (16.2%) compared to SMA (0%).

Conclusions

The burden of hemolysis in blood samples taken from IV cannulae can be effectively reduced with the use of manual aspiration using the S-Monovette® blood collection system as compared to BD-Vacutainer.

The preanalytical process in the emergency department, a European survey

OBJECTIVES

Clinical decision-making in emergency medicine is under constant pressure from demand and performance requirements, with blood tests being a fundamental part of this. However, the preanalytical process has received little attention. Therefore, this study aimed to investigate the quality of preanalytical phase processes in European emergency departments (EDs) from the perspectives of the three main providers: clinicians, nurses, and laboratory specialists.

METHODS

This online survey, distributed among European EDs and laboratories, was supported by the European Society for Emergency Nursing (EUSEN), European Society for Emergency Medicine (EuSEM), and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM). The size of the centres, the European region, the responder's profession and the country's economic condition were used as co-variables.

RESULTS

We included 376 responses from all ED-related professions from 306 European centres. In 66.9% of all ED visits, at least one blood test was performed. Tests were requested mostly by nurses (44.6%) using electronic Order/Entry systems (65.4%). Only a minority (19%) reported not using laboratory quality indicators (QIs). Most responders defined the TAT starting point "when the laboratory receives the sample" (66.1%), defining the goal to be "less than 60 min" (69.9%), but only 42.4% of the centres estimated achieving this goal.

CONCLUSIONS

Our survey illustrates the current situation on preanalytical blood sample processing in European EDs from the clinical and laboratory perspectives. The results emphasise the importance of the IT infrastructure and QI usage in this process and highlight some differences between European regions.

A Single-Center Prospective Study of the Effects of Different Methods of Phlebotomy in the Emergency Department on Blood Sample Hemolysis Rates

INTRODUCTION

Hemolysis is more commonly seen in the emergency department and causes delays in diagnosis, hospitalization, discharge, and treatment of patients. The aim of this study was to determine the most appropriate phlebotomy method and device to reduce blood sample hemolysis in the emergency department.

METHODS

This prospective, comparative descriptive study involved patients who presented to the emergency department with any medical condition and required blood sampling. Patients were divided into 6 groups according to the method of phlebotomy and the device used for phlebotomy. Data were analyzed with logistic regression.

RESULTS

A total of 715 patients participated in the study. The blood sample hemolysis rate in the emergency department was 25.7%. When the hemolysis rates were compared with a steel straight needle or intravenous catheter, it was found that the use of steel straight needle significantly reduced hemolysis. Blood drawing through a 20 G intravenous catheter with Luer-Lock access device reduces the risk of hemolysis. Male sex and difficult blood collection also have been shown to increase the risk of hemolysis.

DISCUSSION

Blood should be drawn with a steel straight needle instead of an intravenous catheter. However, when that is not possible, we recommend the use of a 20 G intravenous catheter with Luer-Lock access device if a blood sample is to be drawn from intravenous line.

Is There a Risk of Misinterpretation of Potassium Concentration from Undetectable Hemolysis Using a POCT Blood Gas Analyzer in the Emergency Department?

Background and Objectives: Hemolysis is reported to be present in up to 10% of blood gas specimens in the central lab; however, few data on the incidence of hemolysis using a point-of-care testing (POCT) blood gas analysis are available in the setting of the emergency department. The aims of this study were: (1) to analyze the prevalence of hemolysis in blood gas samples collected in the ED using a POCT device; and (2) to evaluate the impact of hemolysis on blood sample results and its clinical consequences. Materials and Methods: We collected 525 consecutive POCT arterial blood gas samples using syringes with electrolyte-balanced heparin within 3 different EDs in the metropolitan area of Rome. Immediately after the collection, the blood samples were checked for the presence of hemolysis with a POCT instrument (i.e., HEMCHECK, H-10 ®). The samples were then subsequently processed for blood gasses, and an electrolytes analysis by a second operator blinded for the hemolysis results. A venous blood sample was simultaneously collected, analyzed for it’s potassium value, and used as a reference. Results: Of the samples, 472 were considered for the statistics, while 53 were excluded due to the high percentage of hemolysis due to operator fault in carrying out the measurement. The final mean hemolysis per operator was 12% (±13% SD), and the total final hemolysis was 14.4%.Potassium (K+) was significantly higher in the hemolyzed group compared with the non-hemolyzed sample (4.60 ± 0.11 vs. 3.99 ± 0.03 mEq/L; p < 0.001), and there were differences between arterial potassium versus venous potassium (D(a-v) K+, 0.29 ± 0.06 vs.−0.19 ± 0.02 mEq/L, p < 0.01). A Bland−Altman analysis confirmed that hemolysis significantly overestimated blood potassium level. Conclusion: Almost 12% of POCT blood gas analysis samples performed in the ED could be hemolyzed, and the presence of this hemolysis is not routinely detected. This could cause an error in the interpretation of the results, leading to the consideration of potassium concentrations being below the lower limit within the normal limits and also leading to the diagnosis of false hyperkalemia, which would have potential clinical consequences in therapeutic decision-making in the ED. The routine use of a POCT hemolysis detector could help prevent any misdiagnoses.

Assessing the influence of true hemolysis occurring in patient samples on emergency clinical biochemistry tests results using the VITROS® 5600 Integrated system

Hemolysis is one of the most frequent causes of pre-analytical errors in the emergency department (ED), and it can lead to inaccurate blood results and often requires repeat testing. The purpose of the present study was to evaluate the effects of true hemolysis occurring in ED blood samples on routine clinical biochemistry tests using the VITROS^® 5600 Integrated system. A total of 92 pairs of blood samples were collected from 92 ED patients. Each pair of samples included one hemolyzed sample and one successful (non-hemolyzed) redraw from the same patient. A total of 21 common laboratory analytes and the hemolytic index (HI) were examined. The degree of hemolysis (slight, mild, moderate and heavy) was determined based on the HI. A clinically significant difference in one analyte was defined as a difference greater than its Clinical Laboratory Improvement Amendments of 1988 (CLIA'88) total allowable error (TAE) limits. The results demonstrated that the mean differences in 11 serum analytes (unconjugated bilirubin, Ca²⁺, equivalent CO₂, Cl^-, creatinine, glucose, Mg²⁺, phosphorus, Na⁺, urea nitrogen and uric acid) in hemolyzed and non-hemolyzed samples were within their CLIA'88 TAE limits, while the differences in the other 10 analytes [alanine aminotransferase (ALT), albumin (ALB), amylase (AMYL), aspartate aminotransferase (AST), total bilirubin (TBIL), creatine kinase (CK), CK-myocardial band isoenzyme (CK-MB), lactate dehydrogenase (LDH), K⁺ and total protein (TP)] in paired samples in at least one of the four groups were greater than their CLIA'88 TAE limits. These results suggest that hemolysis had a notable impact on ALT, ALB, AMYL, AST, TBIL, CK, CK-MB, LDH, K⁺ and TP levels. Furthermore, for ALT, AMYL, TBIL and TP, wet chemistry methods displayed superior anti-hemolytic ability compared with dry chemistry methods. Notably, a high concentration of AST was less affected by hemolysis.

Improving the Quality of Venous Blood Sampling Procedure (Phlebotomy): Avoiding Tourniquet Use

Background Phlebotomy guidelines discourage tourniquet use whenever possible. We assessed phlebotomists' capability of not using the tourniquet in venous blood sampling, hypothesizing it to be equal to 50% of the patients attended, and identifying the most frequent venipuncture site.

Materials and Methods We assigned two phlebotomists of the same age (41 years) and experience (20 years) to record 10 phlebotomy days, the first with prioritized and the latter with nonprioritized patients. Each acquired daily data for the number of attended patients, age, gender, frequency of nontourniquet usage, and punctured vein. To test our work hypothesis we used the two-tailed single sample t-test. Differences between age-group means and nontourniquet use means by each phlebotomist were tested by two-tailed t-test for independent means.

Results In 10 phlebotomy days, 683 patients were attended (males 43.2%). We found no statistically significant difference between age-group means. The combined capability of nontourniquet use was 50.5%, which did not differ from our null hypothesis, but the difference in individual group means was statistically significant, the means being 33% and 66.9% (prioritized vs. nonprioritized). The medial cubital vein was the most prone to be punctured (77.7%).

Conclusion Performing phlebotomies without tourniquet was possible in at least half of the attended patients, though it was more limited in specific group populations.

Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays

A number of assay-related issues can affect the performance of cardiac troponin (cTn) measurement in everyday practice. In this respect, it is vital that all information on cTn assays is known and that the performance characteristics of assays are objectively assessed and adequately described. The advent of the latest generation of more sensitive cTn assays has heralded a new wave of information about low concentrations of cTn in blood. These recent generation assays have improved analytical sensitivity and corresponding performance at low cTn concentrations when compared to their predecessors, providing a convincing goal for laboratory medicine in helping clinicians in the diagnosis of acute myocardial infarction. Crucial to the clinical utility of highly sensitive cTn assays is the laboratorians' role in closely scrutinizing proposed assays and defining their value in relation to available evidence. Analytical, as well as pre-analytical and post-analytical, aspects must be documented. In this review, we describe what laboratory professionals should know about their cTn assay performance characteristics and the pre-analytical prerequisites for robustness to ensure optimal post-analytical reporting.

Evaluation of processes, outcomes, and use of midline peripheral catheters for the purpose of blood collection

HIGHLIGHTS

Results added knowledge on use of midline catheters (MCs) for blood sampling. Using MCs for blood withdrawal resulted in low rates of hemolysis (0.69%). Dwell time was longer in those who had blood drawn from their MC. Nurse practices for blood sampling from MCs varied and learned from other nurses.

BACKGROUND

Blood withdrawal from midline catheters (MCs) is done clinically, but no studies were found evaluating outcomes from this procedure, nor were clinical guidelines found. Drawing blood samples from short peripheral catheters is associated with higher hemolysis rates.

METHODS

A prospective, observational, mixed methods study was used to evaluate outcomes from using MCs for blood withdrawal. Focus group sessions were held to evaluate nurses' practices for this procedure.

RESULTS

Data were collected over 3 months on 397 MCs in 378 patients. Hemolysis rates when the MC was used for blood withdrawal was 0.69% in 1021 tests. More than half had blood specimens drawn through the MC, and the time known for the successful withdrawal was on average 64 ± 85 hours. Mean dwell time for all MCs was 108.5 ± 98 hours, and when MCs were used for blood withdrawal, mean dwell time was 127.19 ± 109.13 hours and for MCs not used for blood withdrawal, 88.34 ± 79.86 hours (P < 0.001). In 338 patients who received therapy through their MC (n = 338), 87% completed intended therapy: 88% with blood withdrawal and 81% without blood withdrawal. Qualitative analysis from focus groups demonstrated wide variation in practice for blood sampling from MCs, and most learned techniques from their preceptors, other nurses, or patients.

CONCLUSIONS

Findings indicated that blood withdrawal from one specific type of MC had low rates of hemolysis, increased dwell time, and completion of therapy. More studies are needed to determine best practices for blood sampling through various types of MCs and outcomes.

Seeing Red: Blood Sample Hemolysis Is Associated with Prolonged Emergency Department Throughput

INTRODUCTION

Hemolyzed emergency department (ED) blood specimens impose substantial burdens on various aspects of delivering care. The ED has the highest incidence of hemolysis among hospital departments. This study assessed the association and potential impact of hemolyzed blood samples on patient throughput time using ED length of stay (LOS) as the primary outcome measure.

METHODS

This study was a secondary analysis of data collected during a performance improvement project aimed at reducing the incidence of hemolysis in ED blood specimens. The electronic medical record was queried for potassium orders and results and for key patient throughput time points. Throughput times were stratified according to hemolysis, ED disposition (admitted vs discharged), and Emergency Services Index (ESI) triage categorization. Two-tailed t tests were used to compare throughput times for patients with and without hemolysis.

RESULTS

Potassium values were reported for 11 228 patient visits. The mean ED LOS was 287 minutes for patients with nonhemolyzed samples and 349 minutes for patients who had hemolyzed samples, a mean delay of 62 minutes. The mean throughput time for discharged patients was 92 minutes shorter in the group without hemolysis (337 vs 429 minutes). The mean throughput time for admitted patients was 28 minutes shorter in the group without hemolysis (264 vs 292 minutes). The increased LOS for patients with a hemolyzed blood sample was independent of the most commonly encountered ESI levels.

CONCLUSION

Hemolysis of blood samples obtained in the ED is associated with prolonged patient throughput via delays in patient disposition, independent of various markers of acuity, such as the patients' ultimate disposition or triage categorization.

The Hidden Cost of Hemolyzed Blood Samples in the Emergency Department

BACKGROUND

On average, patients with hemolyzed potassium samples spend about 1 h longer in the emergency department (ED), regardless of acuity level or disposition. We aimed to quantify the direct expenses associated with poor-quality preanalytic blood samples collected in the ED.

METHODS

We created a simple table with a range of direct expenses (i.e., costs) and rates of hemolyzed sample draws, allowing for identification of potential high-level cost-of-care impact analysis. We included a range of costs informed by review of literature on the topic. Those costs range from $600 to $3000 per bed-hour. This amount was inflation adjusted from 1996 to 2020 (1.68 × [direct cost per visit] × [100 000 visits per year/365 days/24 h]). We provided a range of hemolysis incidence based on previously reported data.

RESULTS

We showed that for an ED with 100 000 annual visits, a 40% draw rate for routine chemistries (including potassium), and a 10% hemolysis incidence, the direct cost impact of hemolysis waste is approximately $4 million/year as a result of the 1 h of added length of stay on average for a patient with a hemolyzed blood sample. This amount represents an annualized estimated cost of caring for a patient in the ED with an avoidable extended length of stay.

CONCLUSIONS

The financial burden of poor-quality blood samples can be estimated using cost per bed-hour and rate of sample failure. Similar methodology may identify additional QC issues with previously invisible financial implications.

The impact of blood sampling technique, including the use of peripheral intravenous cannula, on haemolysis rates: A cohort study

AIMS

To explore the relationship between blood sampling techniques and haemolysis.

BACKGROUND

Haemolysis rates of blood samples have been thought to be influenced by the method of collection. There is a lack of research evidence available to clearly show the comparative risk of haemolysis across different blood sampling methods, including venepuncture and use of peripheral intravenous cannulas.

DESIGN

A prospective cohort study. Reporting followed the STROBE checklist.

METHODS

A trained observer was used to record blood sampling techniques over a 10-week period between April and June 2019. These records were then linked to pathology haemolysis results. Multivariable logistic regression was used to model patient and blood draw characteristics affecting haemolysis.

RESULTS

Most of the blood samples were not haemolysed (n = 324, 87.1%). Multivariable analysis showed haemolysis was associated with increased tourniquet duration and if the level of tube was less than half full. Univariable analysis showed haemolysis was associated with increased age of the patient, the difficulty of cannulation/ venepuncture and increased number of attempts. No difference was found in the haemolysis rate related to the qualification of the blood collector.

CONCLUSION

There was no significant difference in haemolysis rates associated with sampling blood from a PIVC compared with venepuncture. Research should be undertaken to determine whether education on the factors influencing haemolysis is useful in decreasing haemolysis rates.

RELEVANCE TO CLINICAL PRACTICE

There was no association with increased haemolysis rates when drawing blood via venepuncture compared with a peripheral intravenous cannula. Haemolysis of blood samples was associated with increased tourniquet duration, if level of the tube was less than half-filled, increased age of the patient and difficulty of blood draw. Awareness of the risk of haemolysis associated with specific blood sampling methods may assist clinicians to improve care.

Emergency Nurses' Knowledge, Attitudes, and Practices Related to Blood Sample Hemolysis Prevention: An Exploratory Descriptive Study

INTRODUCTION

The aim of the study was to identify emergency nurses' knowledge, attitudes, and practices related to blood sample hemolysis prevention and explore associations between these factors and demographic characteristics. The current state is unknown. Understanding baseline knowledge, attitudes, and practices addresses a gap in the literature.

METHOD

An exploratory, descriptive design with cross-sectional survey methodology employing a study-specific instrument was used.

RESULTS

Request for participation email was sent to a random sample of 5000 Emergency Nurses Association members, and 427 usable surveys were returned (response rate = 8.5%). Mean years in nursing was 13.85 (standard deviation = 10.78), and 226 (52.9%) were certified emergency nurses. Only 85 participants (19.9%) answered all 3 knowledge questions correctly. Answering the 3 knowledge questions correctly was significantly associated with being a certified emergency nurse (χ² = 7.15, P < .01). Participant responses to attitude items about the sequelae of blood sample hemolysis were skewed toward agreement, and most attitude items were associated with whom participants reported as being primarily responsible for phlebotomy. Emergency nurses remain primarily responsible for phlebotomy as well as addressing hemolyzed samples, but few reported that blood sample hemolysis was addressed at a departmental level.

DISCUSSION

Findings suggest that emergency nurses lack some knowledge related to blood sample hemolysis prevention best practices. Attitudes toward phlebotomy practices may be 1 reason practice has not changed. Every effort should be made to prevent hemolyzed blood samples to decrease delays and costs in emergency care.

Effect of haemolysis on an enzymatic measurement of ethanol

Introduction

We investigated the interference of haemolysis on ethanol testing carried out with the Synchron assay kit using an AU680 autoanalyser (Beckman Coulter, Brea, USA).

Materials and methods

Two tubes of plasma samples were collected from 20 volunteers. Mechanical haemolysis was performed in one tube, and no other intervention was performed in the other tube. After centrifugation, haemolysed and non-haemolysed samples were diluted to obtain samples with the desired free haemoglobin (Hb) values (0, 1, 2, 5, 10 g/L). A portion of these samples was then separated, and ethanol was added to the separated sample to obtain a concentration of 86.8 mmol/L ethanol. After that, these samples were diluted with ethanol-free samples with the same Hb concentration to obtain samples containing 43.4, 21.7, and 10.9 mmol/L. Each group was divided into 20 equal parts, and an ethanol test was carried out. The coefficient of variation (CV), bias, and total error (TE) values were calculated.

Results

The TE values of haemolysis-free samples were approximately 2-5%, and the TE values of haemolysed samples were approximately 10-18%. The bias values of haemolysed samples ranged from nearly - 6.2 to - 15.7%.

Conclusions

Haemolysis led to negative interference in all samples. However, based on the 25% allowable total error value specified for ethanol in the Clinical Laboratory Improvement Amendments (CLIA 88) criteria, the TE values did not exceed 25%. Consequently, ethanol concentration can be measured in samples containing free Hb up to 10 g/L.

Blood sampling from peripherally inserted central catheter is effective and safe for patients with head and neck cancers

OBJECTIVE

To evaluate the validity of laboratory tests for blood sampling from a peripherally inserted central catheter.

METHODS

A total of 22 patients diagnosed with head and neck cancers were enrolled. In total, 101 paired blood samples were taken both via venipuncture and peripherally inserted central catheter for hematology and biochemistry testing. Paired t tests and linear correlation analysis were used to evaluate the results. Blood sampling-related pain was recorded by visual analogue scales and numerical rating scales. Infusion occlusion, hemolysis, and catheter-related blood stream infection were also recorded.

RESULTS

The peripherally inserted central catheter-associated test results were slightly lower than those with venipuncture. Some parameters differed more than others. However, the degree of difference was less than 5% for every pair. There was a high correlation between the test results with two methods of blood sampling with the representative equation approximately being "y = x." According to visual analogue scales and numerical rating scale analysis, the pain degree with peripherally inserted central catheter was significantly lower than that of the venipuncture (p < 0.001). No case of infusion occlusion, catheter-related blood stream infection was reported with both methods. Hemolysis rate in blood samples from peripherally inserted central catheter (1/101) was much lower than that seen with venipuncture (11/101) with significant difference (p = 0.0056).

CONCLUSION

Blood sampling via peripherally inserted central catheter and venipuncture showed equivalent reliability in laboratory testing. Compared with venipuncture, blood sampling via peripherally inserted central catheter causes less pain and is safer. Blood sampling via peripherally inserted central catheter is strongly recommended for clinical use.

Hemolytic specimens in complete blood cell count: Red cell parameters could be revised by plasma free hemoglobin

Introduction

Hemolysis is the main cause of unqualified clinical samples. In this study, we established a method for detecting and evaluating hemolysis in whole blood test. We used a mathematical formula for correcting the influence of hemolysis on complete blood cell count (CBC) so as to avoid re‐venipuncture and obtain more accurate parameters of red blood cell detection, reduce the burden of patients, and improve the efficiency of diagnosis and treatment.

Methods

Hemolytic samples were selected and then corrected using the new formula. Plasma free hemoglobin (fHB) was used as the criterion to determine the degree of hemolysis; the uncertainty of measurement is acceptable as the limit value of deviation between the measured value and the revised value. Hemolysis simulation analysis in vitro and continuous monitoring of clinical patients were used to verify the correction effect.

Results

A total of 83 clinical samples with hemolysis were collected and analyzed; fHB 1.4 g/L was selected as the unacceptable value for clinical hemolysis detection. In hemolytic samples, the red blood cell parameters corrected by formula are significantly different from those uncorrected and had a good consistency with those before hemolysis.

Conclusion

The results show that the hemolysis phenomenon of CBC has a significant impact on routine blood testing. By using the new formula, the influence of hemolysis on erythrocyte and related parameters can be quickly and easily corrected, thus avoiding venipuncture again for re‐examination, reducing diagnostic errors, and saving medical resources.

A New Test for the Detection of Direct Oral Anticoagulants (Rivaroxaban and Apixaban) in the Emergency Room Setting

Determining whether a patient has taken a direct oral anticoagulant (DOAC) is critical during the periprocedural and preoperative period in the emergency department. However, the inaccessibility of complete medical records, along with the generally inconsistent sensitivity of conventional coagulation tests to these drugs, complicates clinical decision making and puts patients at risk of uncontrollable bleeding. In this study, we evaluate the utility of inhibitor-II-X (i-II-X), a novel, microfluidics-based diagnostic assay for the detection and identification of Factor Xa inhibitors (FXa-Is) in an acute care setting.

DESIGN

First-in-human, 91-patient, single-center retrospective pilot study.

SETTING

Emergency room.

PATIENTS

Adult patients admitted into the emergency department, which received any clinician-ordered coagulation test requiring a 3.2% buffered sodium citrate blood collection tube.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Plasma samples from patients admitted to the emergency department were screened for the use of FXa-Is, including apixaban and rivaroxaban, within the past 24 hours using our new i-II-X microfluidic test. i-II-X results were then compared with results from conventional coagulation tests, including prothrombin time (PT) and international normalized ratio (INR), which were ordered by treating clinicians, and an anti-Xa assay for rivaroxaban. The i-II-X test detected DOACs in samples collected from the emergency department with 95.20% sensitivity and 100.00% specificity. Unlike PT and INR, i-II-X reliably identified patients who had prolonged clotting times secondary to the presence of a FXa-I.

CONCLUSIONS

The i-II-X test overcomes the limitations of currently available coagulation tests and could be a useful tool by which to routinely screen patients for DOACs in emergency and critical care settings. Our new diagnostic approach is particularly relevant in clinical situations where medical records may be unavailable, or where precautions need to be taken prior to invasive interventions, such as specific reversal agent administration.

Drawing blood from peripheral intravenous cannula compared with venepuncture: A systematic review and meta-analysis

AIMS

To synthesize the evidence evaluating if blood samples are similar when obtained from peripheral intravenous cannula compared with venepuncture.

DESIGN

A systematic review and meta-analysis was undertaken.

DATA SOURCES

Searches were conducted in databases for English language studies between January 2000-December 2018.

REVIEW METHODS

The search adhered to the Meta-analysis of Observational Studies in Epidemiology guidelines. The methodological quality of studies was assessed using Joanna Briggs critical appraisal instruments. The overall quality of the evidence was assessed using the GRADE.

RESULTS

Sixteen studies were identified. Findings suggest haemolysis rates are higher in blood sampled from peripheral intravenous cannula. However, haemolysis rates may be lower if a peripheral intravenous cannula blood sampling protocol is followed. For equivalence of blood test results, even though some results were outside the laboratory, allowable error and were outside the Bland-Altman Level of Agreement, none of these values would have required clinical intervention. With regard to the contamination rates of blood cultures, the results were equivocal.

CONCLUSION

Further research is required to inform the evidence for best practice recommendations, including, if a protocol for drawing blood from a peripheral cannula is of benefit for specific patient populations and in other settings.

IMPACT

Venepuncture can provoke pain, anxiety and cause trauma to patients. Guidelines recommend blood samples from peripheral intravenous cannula be taken only on insertion. Anecdotal evidence suggests drawing blood from existing cannulas may be a common practice. Further research is required to resolve this issue.

Improved quality of samples and laboratory turnaround time using 3.5 mL low vacuum BD Vacutainer® Barricor tubes in the emergency department

Background

Centrifugation is a consuming time step which participates to increase the turnaround time (TAT) in laboratories, likewise hemolysis sample that needs a re-sampling could delay management of patients. Recently, it has been postulated that BD Barricor™ tube could allow to decrease the centrifugation time and prevent hemolysis, two key feature to ensure high-quality results.

Aim of the study was to evaluate the impact of replacing 4 mL BD vacutainer heparin lithium tube by low vacuum 3.5 mL BD vacutainer Barricor™ tube in an emergency department (ED) on hemolysis rate and TAT.

Methods

Data of hemolysis index (HI) and TAT were compared between the first period of 15 days using 4 mL BD vacutainer heparin lithium tubes with 15 min at 2000xg as centrifugation setting and a second period of 15 days using BD vacutainer Barricor™ tube centrifuged 3 min at 4000xg.

Results

A significantly reduced time duration between reception of sample and available results in informatics lab system was observed with the reduction time of centrifugation allowed by use of Barricor™ tube compared to regular heparin lithium tubes (p < 0.001). A significative decrease in hemolysis rate also occurred in the second period as samples with HI < 10 reached from 52.5% in the first period to 68.5% (p < 0.001) in the second.

Conclusion

Low vacuum Barricor^TM tubes allowing a higher speed of centrifugation improve lab TAT without impairment of sample quality as a significant reduction of hemolysis was observed, a double advantage which is of particular interest for ED.

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Improving turnaround time and quality samples is a challenge for all laboratories.

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Hemolyzed samples occurrence is higher in the emergency department.

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Low vacuum tube can reduce the hemolysis rate of blood sampling.

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Higher speed centrifugation could reduce centrifugation time and turnaround time.

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Low vacuum Barricor tube in emergency unit improve hemolysis rate and turnaround time.

[Diagnosis of myocardial infarction in critically ill, ventilated patients]

Elevated cardiac troponin values are frequently observed in critically ill patients. These are often not due to myocardial infarction (MI) but caused by various other etiologies of myocardial injury. Understanding the etiology of any troponin elevation is of enormous importance for management and therapy. According to the fourth version of the Universal Definition of MI, myocardial injury is present if at least one troponin value is above the 99th percentile upper reference limit and considered acute, when a rise and/or fall occurs. Patients with acute MI are a subgroup of patients with acute myocardial injury, who present in an ischemic clinical context. Variables defining the clinical criteria of MI include symptoms of ischemia, presumably new electrocardiographic (ECG) changes or imaging evidence of new loss of viable myocardium or regional wall motion abnormalities, or detection of an intracoronary thrombus. In critically ill or mechanically ventilated patients, the diagnosis of MI is challenging due to limitations in history taking, co-existence of comorbidities, overlapping symptoms and equivocal or unspecific ECG changes. This article presents the diagnostic criteria of the Universal MI definition, discusses subtypes of MI and focuses on various differential diagnoses. Furthermore, implications of diagnosis of MI in critically ill patients, especially regarding the use of ECG and troponin assays, are discussed.

Influence of hemolysis on clinical chemistry parameters determined with Beckman Coulter tests - detection of clinically significant interference

The aim of this study was to examine the influence of hemolysis on 25 clinical chemistry parameters and to compare the resulting bias with clinically significant differences and the manufacturer's specifications. Using freeze-thawing of the treated blood aliquot of each subject (N = 17), four hemolysis levels were prepared with hemolysis index (HI) and hemoglobin concentration as follows: (+)=0.5-0.99 g/L, (2+)=1-1.99 g/L, (3+)=2-2.99 g/L and (4+)=3-4.99 g/L. All analytes were tested on the Beckman Coulter AU480 analyzer using proprietary reagents. It was considered that the interference was detected if the 95% confidence interval for mean differences (%) between hemolyzed and non-hemolyzed samples did not include zero. Clinically significant interference was judged against reference change value (RCV). Hemolysis interference was detected for: alpha-amylase, alkaline phosphatase (ALP), aspartate aminotransferase (AST), total and conjugated bilirubin, creatine kinase (CK), CK-MB, ɣ-glutamyltransferase (GGT), iron, lactate dehydrogenase (LD), magnesium, potassium, total protein and uric acid at HI=(1+); alanine aminotransferase (ALT) and phosphate at HI=(2+); urea at HI=(3+); albumin and cholinesterase at HI=(4+). Even at the greatest hemolysis degree, HI=(4+), no interference was detected for calcium, chloride, creatinine, C-reactive protein (CRP), glucose and sodium. Clinically significant difference was exceeded for LD at HI=(1+); CK-MB at HI=(2+); AST and potassium at HI=(3+); total bilirubin at HI=(4+). The presented results did not support the manufacturer's claim for CK and GGT. Establishing HI thresholds for reporting or suppressing test results is the responsibility of each laboratory, taking into account the manufacturer's data, but also its own investigations.