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.

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.

A Comparison of Five SARS-CoV-2 Molecular Assays With Clinical Correlations.

OBJECTIVES: Comparative assessments of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) molecular assays that have been operationalized through the US Food and Drug Administration's Emergency Use Authorization process are warranted to assess real-world performance. Characteristics such as sensitivity, specificity, and false-negative rate are important to inform clinical use. METHODS: We compared five SARS-CoV-2 assays using nasopharyngeal and nasal swab specimens submitted in transport media; we enriched this cohort for positive specimens, since we were particularly interested in the sensitivity and false-negative rate. Performance of each test was compared with a composite standard. RESULTS: The sensitivities and false-negative rates of the 239 specimens that met inclusion criteria were, respectively, as follows: Centers for Disease Control and Prevention 2019 nCoV Real-Time RT-PCR Diagnostic Panel, 100% and 0%; TIB MOLBIOL/Roche z 480 Assay, 96.5% and 3.5%; Xpert Xpress SARS-CoV-2 (Cepheid), 97.6% and 2.4%; Simplexa COVID-19 Direct Kit (DiaSorin), 88.1% and 11.9%; and ID Now COVID-19 (Abbott), 83.3% and 16.7%. CONCLUSIONS: The assays that included a nucleic acid extraction followed by reverse transcription polymerase chain reaction were more sensitive than assays that lacked a full extraction. Most false negatives were seen in patients with low viral loads, as extrapolated from crossing threshold values.

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.

Preanalytic Factors Associated With Hemolysis in Emergency Department Blood Samples.

CONTEXT: - Hemolysis of emergency department blood samples is a common occurrence and has a negative impact on health care delivery. OBJECTIVES: - To determine the effect of preanalytic factors (straight stick, intravenous [IV] line, needle gauge, location of blood draw, syringe versus vacuum tube use, tourniquet time) on hemolysis in emergency department blood samples. DESIGN: - A single 65 000-visit emergency department's electronic health record was queried for emergency department potassium results and blood draw technique for all samples obtained in calendar year 2014, resulting in 54 531 potassium results. Hemolyzed potassium was measured by hemolysis index. Comparisons of hemolysis by sampling technique were conducted by χ2 tests. RESULTS: - Overall hemolysis was 10.0% (5439 of 54 531). Hemolysis among samples obtained from straight stick was significantly less than among those obtained with IV line (5.4% [33 of 615] versus 10.2% [4821 of 47 266], P < .001). For IV-placed blood draws, antecubital location had a statistically significant lower overall hemolysis compared with other locations: 7.4% (2117 of 28 786) versus 14.6% (2622 of 17 960) ( P < .001). For blood drawn with a syringe compared with vacuum, hemolysis was 13.0% (92 of 705) and 11.0% (1820 of 16 590), respectively ( P = .09, not significant). For large-gauge IV blood draws versus smaller-gauge IV lines, a lower hemolysis was also observed (9.3% [3882 of 41 571] versus 16.7% [939 of 5633]) ( P < .001). For IV-drawn blood with tourniquet time less than 60 seconds, hemolysis was 10.3% (1362 of 13 162) versus 13.9% for more than 60 seconds (532 of 3832), P < .001. CONCLUSIONS: - This study confirmed previous findings that straight stick and antecubital location are significantly associated with reduced hemolysis and indicated that shorter tourniquet time and larger gauge for IV draws were significantly associated with lower hemolysis.

Impact of Use of Smaller Volume, Smaller Vacuum Blood Collection Tubes on Hemolysis in Emergency Department Blood Samples.

OBJECTIVES: Hemolyzed blood samples commonly occur in hospital emergency departments (EDs). Our objective was to determine whether replacing standard large-volume/high-vacuum sample tubes with low-volume/low-vacuum tubes would significantly affect ED hemolysis. METHODS: This was a prospective intervention of the use of small-volume/vacuum collection tubes. We evaluated all potassium samples in ED patients and associated hemolysis. We used χ2 tests to compare hemolysis incidence prior to and following utilization of small tubes for chemistry collection. RESULTS: There were 35,481 blood samples collected during the study period. Following implementation of small-volume tubes, overall hemolysis decreased from a baseline of 11.8% to 2.9% (P < .001) with corresponding reductions in hemolysis with comment (8.95% vs 1.99%; P < .001) gross hemolysis (2.84% vs 0.90%; P < .007). CONCLUSIONS: This work demonstrates that significant improvements in ED hemolysis can be achieved by utilization of small-volume/vacuum sample collection tubes.

Does Pneumatic Tube System Transport Contribute to Hemolysis in ED Blood Samples?

INTRODUCTION: Our goal was to determine if the hemolysis among blood samples obtained in an emergency department and then sent to the laboratory in a pneumatic tube system was different from those in samples that were hand-carried. METHODS: The hemolysis index is measured on all samples submitted for potassium analysis. We queried our hospital laboratory database system (SunQuest(®)) for potassium results for specimens obtained between January 2014 and July 2014. From facility maintenance records, we identified periods of system downtime, during which specimens were hand-carried to the laboratory. RESULTS: During the study period, 15,851 blood specimens were transported via our pneumatic tube system and 92 samples were hand delivered. The proportions of hemolyzed specimens in the two groups were not significantly different (13.6% vs. 13.1% [p=0.90]). Results were consistent when the criterion was limited to gross (3.3% vs 3.3% [p=0.99]) or mild (10.3% vs 9.8% [p=0.88]) hemolysis. The hemolysis rate showed minimal variation during the study period (12.6%-14.6%). CONCLUSION: We found no statistical difference in the percentages of hemolyzed specimens transported by a pneumatic tube system or hand delivered to the laboratory. Certain features of pneumatic tube systems might contribute to hemolysis (e.g., speed, distance, packing material). Since each system is unique in design, we encourage medical facilities to consider whether their method of transport might contribute to hemolysis in samples obtained in the emergency department.

Comparison of symmetric dimethylarginine with creatinine, cystatin C and their eGFR equations as markers of kidney function.

OBJECTIVES: Symmetric dimethylarginine (SDMA) is a catabolic product of arginine-methylated proteins and is an emerging biomarker for kidney function. A limited number of studies in selected populations have shown good correlation between SDMA and a few known markers of glomerular filtration rate (GFR). However, a comprehensive comparison of SDMA with all existing serum endogenous markers in a population with varied kidney function and against measured GFR is lacking. The objective of this study was to compare the correlations of SDMA, creatinine, cystatin C and their eGFR equations against GFR measured by iothalamate clearance in an adult population with varied kidney function. DESIGN & METHODS: Left-over serum and plasma specimens were collected from 40 adults with normal and reduced kidney function. GFR was measured using a radioactive iothalamate procedure. Creatinine and cystatin C were measured on Roche Cobas 8000. SDMA was measured by a published liquid chromatography-tandem mass spectrometry method. RESULTS: SDMA correlated highly with measured GFR (r=-0.84), which was better than creatinine (r=-0.70) but equivalent to cystatin C (r=-0.86) and the eGFR equations [MDRD and CKD-EPI (separate and combined)]. CONCLUSIONS: SDMA is a strong marker of kidney function and further studies are needed to establish an eGFR formula that includes it for widespread clinical use.

Contemporary bloodletting in cardiac surgical care.

BACKGROUND: Health care providers are seldom aware of the frequency and volume of phlebotomy for laboratory testing, bloodletting that often leads to hospital-acquired anemia. Our objectives were to examine the frequency of laboratory testing in patients undergoing cardiac surgery, calculate cumulative phlebotomy volume from time of initial surgical consultation to hospital discharge, and propose strategies to reduce phlebotomy volume. METHODS: From January 1, 2012 to June 30, 2012, 1,894 patients underwent cardiac surgery at Cleveland Clinic; 1,867 had 1 hospitalization and 27 had 2. Each laboratory test was associated with a test name and blood volume. Phlebotomy volume was estimated separately for the intensive care unit (ICU), hospital floors, and cumulatively. RESULTS: A total of 221,498 laboratory tests were performed, averaging 115 tests per patient. The most frequently performed tests were 88,068 blood gas analyses, 39,535 coagulation tests, 30,421 complete blood counts, and 29,374 metabolic panels. Phlebotomy volume differed between ICU and hospital floors, with median volumes of 332 mL and 118 mL, respectively. Cumulative median volume for the entire hospital stay was 454 mL. More complex procedures were associated with higher overall phlebotomy volume than isolated procedures; eg, combined coronary artery bypass grafting (CABG) and valve procedure median volume was 653 mL (25th/75th percentiles, 428 of 1,065 mL) versus 448 mL (284 of 658 mL) for isolated CABG and 338 mL (237 of 619) for isolated valve procedures. CONCLUSIONS: We were astonished by the extent of bloodletting, with total phlebotomy volumes approaching amounts equivalent to 1 to 2 red blood cell units. Implementation of process improvement initiatives can potentially reduce phlebotomy volumes and resource utilization.

Progress of liquid chromatography-mass spectrometry in measurement of vitamin D metabolites and analogues.

OBJECTIVE: Clinical testing for vitamin D nutritional status has experienced tremendous growth in the past several years, driven by research results linking various diseases with low serum 25-hydroxyvitamin D [25(OH)D] levels. Meanwhile, interest in the pathophysiological mechanism elucidation and pharmaceutical applications requires measurement of vitamin D metabolites and analogues. Liquid chromatography-mass spectrometry (LC-MS) has been increasingly utilized in these applications. In this work, our objective was to critically review the progress of LC-MS application in measuring vitamin D metabolites and analogues in biological fluids. METHODS: The LC-MS methods included were selected from those searchable in PubMed up to January 2010. RESULTS AND CONCLUSION: LC-MS has unique advantages in measuring various vitamin D metabolites and analogues due to its flexibility, sensitivity, and specificity. Despite some controversies over serum 25(OH)D tests, LC-MS will be used for standardizing serum 25(OH)D assays using reference materials available from the National Institute of Standards and Technology.

Performance characteristics of a new levetiracetam immunoassay and method comparison with a high-performance liquid chromatography method.

BACKGROUND: Although levetiracetam is recognized for ease of dosing and being well tolerated, therapeutic drug monitoring is potentially useful in certain clinical situations. High-performance liquid chromatography has been commonly used for measuring levetiracetam. Recently, a homogeneous immunoassay for levetiracetam measurement in serum and plasma was introduced by ARK Diagnostics, Inc. The goal of this work was to validate this assay on a random access instrument. DESIGN AND METHODS: This immunoassay was established on the Siemens ADVIA 1200 automated chemistry analyzer. The intraday precision was assessed by 10 replicates of two levels of quality control materials in a batch, whereas interday precision was estimated by assaying the same materials one set per day for 20 days. Linearity was evaluated by serially diluting the highest calibrator and a high patient specimen run in triplicate, whereas the lower limit of quantification was confirmed by 10 measurements of a low-level specimen diluted from a calibrator and another from a diluted patient specimen. This method was compared with a commercial high-performance liquid chromatography method (Chromsystems) using 63 specimens from patients who were on levetiracetam therapy. RESULTS: The assay cycle was 10 minutes with a theoretical throughput of 800 per hour. The intra- (n = 10) and interday (n = 20) coefficients of variation were 8.1% or less for the two levels tested. The manufacturer-claimed analytical measurable range (2.0-100.0 µg/mL) was confirmed by serial dilution and lower limit of quantification experiments. Among the 63 patient samples studies, four showed levetiracetam levels below 2.0 µg/mL by both methods. Deming regression using the remaining 59 paired patient results by ARK immunoassay and the high-performance liquid chromatography method showed a correlation coefficient of 0.9962, a linear regression slope of 0.98, and an intercept of 0.61 with a mean bias of 0.04%. CONCLUSION: The ARK immunoassay is suitable for clinical use of monitoring levetiracetam levels in serum/plasma on an automated chemistry analyzer (Siemens ADVIA 1200).

CD22 expression on blastic plasmacytoid dendritic cell neoplasms and reactivity of anti-CD22 antibodies to peripheral blood dendritic cells.

We identified CD22 expression on a blastic plasmacytoid dendritic cell (pDC) neoplasm presenting as a leukemia in a child. CD22 expression, as determined by the antibody s-HCL-1, was also noted on the neoplastic cells from three additional patients with blastic pDC tumors identified at our institution. Subsequently we determined that peripheral blood pDCs react with the s-HCL-1 antibody demonstrating that normal pDCs express CD22. Evaluation of five additional anti-CD22 antibodies indicated that staining of pDCs with these reagents was poor except for s-HCL-1. Therefore, the detection of CD22 on pDCs is best demonstrated with the use of this specific antibody clone. All anti-CD22 antibodies stained conventional DCs. We also evaluated the reactivity of the anti-CD22 antibodies with basophils and noted that the pattern of staining was similar to that seen with pDCs. The studies demonstrate that normal DCs and pDC neoplasms express CD22, and highlight clone specific differences in anti-CD22 antibody reactivity patterns on pDCs and basophils.

Evaluating the contribution of base stacking during translesion DNA replication.

Despite the nontemplating nature of the abasic site, dAMP is often preferentially inserted opposite the lesion, a phenomenon commonly referred to as the "A-rule". We have evaluated the molecular mechanism accounting for this unique behavior using a thorough kinetic approach to evaluate polymerization efficiency during translesion DNA replication. Using the bacteriophage T4 DNA polymerase, we have measured the insertion of a series of modified nucleotides and have demonstrated that increasing the size of the nucleobase does not correlate with increased insertion efficiency opposite an abasic site. One analogue, 5-nitroindolyl-2'-deoxyriboside triphosphate, was unique as it was inserted opposite the lesion with approximately 1000-fold greater efficiency compared to that for dAMP insertion. Pre-steady-state kinetic measurements yield a kpol value of 126 s(-1) and a Kd value of 18 microM for the insertion of 5-nitroindolyl-2'-deoxyriboside triphosphate opposite the abasic site. These values rival those associated with the enzymatic formation of a natural Watson-Crick base pair. These results not only reiterate that hydrogen bonding is not necessary for nucleotide insertion but also indicate that the base-stacking and/or desolvation capabilities of the incoming nucleobase may indeed play the predominant role in generating efficient DNA polymerization. A model accounting for the increase in catalytic efficiency of this unique nucleobase is provided and invokes pi-pi stacking interactions of the aromatic moiety of the incoming nucleobase with aromatic amino acids present in the polymerase's active site. Finally, differences in the rate of 5-nitroindolyl-2'-deoxyriboside triphosphate insertion opposite an abasic site are measured between the bacteriophage T4 DNA polymerase and the Klenow fragment. These kinetic differences are interpreted with regard to the differences in various structural components between the two enzymes and are consistent with the proposed model for DNA polymerization.

Evaluating the effects of enhanced processivity and metal ions on translesion DNA replication catalyzed by the bacteriophage T4 DNA polymerase.

The fidelity of DNA replication is achieved in a multiplicative process encompassing nucleobase selection and insertion, removal of misinserted nucleotides by exonuclease activity, and enzyme dissociation from primer/templates that are misaligned due to mispairing. In this study, we have evaluated the effect of altering these kinetic processes on the dynamics of translesion DNA replication using the bacteriophage T4 replication apparatus as a model system. The effect of enhancing the processivity of the T4 DNA polymerase, gp43, on translesion DNA replication was evaluated using a defined in vitro assay system. While the T4 replicase (gp43 in complex with gp45) can perform efficient, processive replication using unmodified DNA, the T4 replicase cannot extend beyond an abasic site. This indicates that enhancing the processivity of gp43 does not increase unambiguously its ability to perform translesion DNA replication. Surprisingly, the replicase composed of an exonuclease-deficient mutant of gp43 was unable to extend beyond the abasic DNA lesion, thus indicating that molecular processes involved in DNA polymerization activity play the predominant role in preventing extension beyond the non-coding DNA lesion. Although neither T4 replicase complex could extend beyond the lesion, there were measurable differences in the stability of each complex at the DNA lesion. Specifically, the exonuclease-deficient replicase dissociates at a rate constant, k(off), of 1.1s(-1) while the wild-type replicase remains more stably associated at the site of DNA damage by virtue of a slower measured rate constant (k(off) 0.009s(-1)). The increased lifetime of the wild-type replicase suggests that idle turnover, the partitioning of the replicase from its polymerase to its exonuclease active site, may play an important role in maintaining fidelity. Further attempts to perturb the fidelity of the T4 replicase by substituting Mn(2+) for Mg(2+) did not significantly enhance DNA synthesis beyond the abasic DNA lesion. The results of these studies are interpreted with respect to current structural information of gp43 alone and complexed with gp45.

Bcl-2 on the endoplasmic reticulum regulates Bax activity by binding to BH3-only proteins.

Bcl-2 family members have been shown to be key mediators of apoptosis as either pro- or anti-apoptotic factors. It is thought that both classes of Bcl-2 family members act at the level of the mitochondria to regulate apoptosis, although the founding anti-apoptotic family member, Bcl-2 is localized to the endoplasmic reticulum (ER), mitochondrial, and nuclear membranes. In order to better understand the effect of Bcl-2 localization on its activity, we have utilized a Bcl-2 mutant that localizes only to the ER membrane, designated Bcl-2Cb5. Bcl-2Cb5 was expressed in MDA-MB-468 cells, which protected against apoptosis induced by the kinase inhibitor, staurosporine. Data presented here show that Bcl-2Cb5 inhibits this process by blocking Bax activation and cytochrome c release. Furthermore, we show that Bcl-2Cb5 can inhibit the activation of a constitutively mitochondrial mutant of Bax, indicating that an intermediate between Bcl-2 on the ER and Bax on the mitochondria must exist. We demonstrate that this intermediate is likely a BH3-only subfamily member. Data presented here show that Bcl-2Cb5 can sequester a constitutively active form of Bad (Bad3A) from the mitochondria and prevent it from activating Bax. These data suggest that Bcl-2 indirectly protects mitochondrial membranes from Bax, via BH3-only proteins.