Impact of blood volume, air exposure duration, transport duration, and testing delay on plasma total carbon dioxide in simulated open collections using microtainers.

Background: Exposing blood specimens to air reduces plasma total carbon dioxide (TCO). We evaluated the degree of TCO reduction attributed to open collection of neonatal blood in BD microtainers® (microtainers), microtainer transport duration and delayed testing of open plasma aliquots.

Methods: Venous blood was aliquoted into open microtainers in a 3x4 factorial design to simulate combined effects of blood volume (0.

Whole Blood Cardiac Troponin "Triaging" to Improve Early Detection of Myocardial Injury at a Pediatric Hospital.

Background: The importance of offering on-site cardiac troponin (cTn) testing at pediatric hospitals may be underappreciated. We developed a rapid rule-in process for myocardial injury at a pediatric hospital experiencing delays in off-site high-sensitivity cardiac troponin T (hs-cTnT) testing.

Methods: Collect-to-verify turnaround times (TATs) for off-site testing were reviewed.

Resolution of PTHrP-Mediated Hypercalcemia Following Treatment with Dual BRAF/MEK Inhibition for BRAFV600E-Positive Metastatic Ameloblastoma.

Ameloblastoma is a rare odontogenic tumor which may be complicated by hypercalcemia in advanced disease. Tumoral parathyroid hormone-related peptide (PTHrP) production and local osteolysis from paracrine factors have been proposed as mechanisms. Mitogen-activated protein kinase (MAPK) inhibitors have been successfully used in ameloblastomas with BRAF V600E mutation to reduce symptoms and decrease tumor burden.

Distribution of videos demonstrating best practices in preventing hemolysis is associated with reduced hemolysis among nurse-collected specimens in hospitals.

Background: Minimizing hemolysis during phlebotomy ensures accurate chemistry results and reduces test cancellations and specimen recollections. We developed videos demonstrating best practices to reduce hemolysis and tested whether distribution to clinical nurse educators (CNEs) for provision to nursing staff affected the degree of specimen hemolysis in hospital inpatient units and outpatient clinics.

Methods: Videos of common blood collections demonstrating best practices to reduce hemolysis were filmed and then distributed via email link to all hospital-based CNEs in Calgary, Alberta, Canada.

A pragmatic randomized controlled trial of rapid on-site influenza and respiratory syncytial virus PCR testing in paediatric and adult populations.

Background: Rapid/point-of-care respiratory virus nucleic acid tests (NAT) may improve oseltamivir, antibiotic, diagnostic test, and hospital bed utilization. Previous randomized controlled trials (RCT) on this topic have not used standard procedures of an accredited healthcare and laboratory system.

Methods: We conducted a parallel RCT at two hospitals [paediatric = Alberta Children's Hospital (ACH); primarily adult = Peter Lougheed Centre (PLC)].

Drug testing in support of the diagnosis of neonatal abstinence syndrome: The current situation.

Illicit drug use during pregnancy is a concern worldwide, with many international studies describing attempted strategies to mitigate this problem. Drug misuse during pregnancy is associated with significant maternal as well as perinatal complications, which include a high incidence of stillbirths, fetal distress, neonatal abstinence syndrome (NAS) and increased neonatal mortality. Unfortunately, the identification of a drug-exposed mother or neonate is challenging.

Low partial pressure of oxygen causes significant and unrecognized under-recovery of glucose on blood gas analyzers.

Background: Blood gas analyzers employing glucose-oxidase biosensors under-recover glucose when pO is low. The manufacturer of the GEM®Premier™ series of analyzers introduced an algorithm to detect specimens at risk of low pO interference. We investigated the reliability of this algorithm.

Not T too! False elevations in high-sensitivity cardiac troponin T (hs-TnT) following specimen transport.

Though false elevations attributed to preanalytical specimen handling have been widely reported for Troponin I (TnI), Troponin T (TnT) has appeared more robust to falsely elevated Tn. We describe reproducible false elevations in high sensitivity TnT (hs-TnT) in specimens after courier transport in plasma separator tubes (PST) off-site for testing. Hs-TnT was measured under 5 different conditions: 1) at collection location (N = 24); 2) after transport upright in racks (N = 66); 3) after transport with no control over tube agitation (N = 69); 4) on transported aliquots (N = 84); or 5) immediately after transport with no control over tube agitation (N = 16), followed by keeping the specimen upright and re-measuring at 1hr, 2hr, 4hr, and 20-24hrs (N = 6).

Filling in the GAPS: validation of anion gap (AGAP) measurement uncertainty estimates for use in clinical decision making.

Objectives: We compare measurement uncertainty (MU) calculations to real patient result variation observed by physicians using as our model anion gap (AGAP) sequentially measured on two different instrument types. An approach for discretely quantifying the pre-analytical contributions and validating AGAP MU estimates for interpretation of patient results is proposed.

Methods: AGAP was calculated from sodium, chloride, and bicarbonate reported from chemistry or blood gas analyzers which employ different methodologies and specimen types.

Prospective comparative evaluation of the European Society of Cardiology (ESC) 1-hour and a 2-hour rapid diagnostic algorithm for myocardial infarction using high-sensitivity troponin-T.

Objective: Both 1- and 2-hour rapid diagnostic algorithms using high-sensitivity troponin (hs-cTn) have been validated to diagnose acute myocardial infarction (MI), leaving physicians uncertain which algorithm is preferable. The objective of this study was to prospectively evaluate the diagnostic performance of 1- and 2-hour algorithms in clinical practice in a Canadian emergency department (ED).

Methods: ED patients with chest pain had high-sensitivity cardiac troponin-T (hs-cTnT) collected on presentation and 1- and 2-hours later at a single academic centre over a 2-year period.

Low High-Sensitivity Troponin Thresholds Identify Low-Risk Patients With Chest Pain Unlikely to Benefit From Further Risk Stratification.

Background: Very low high-sensitivity cardiac troponin T (hs-cTnT) thresholds on presentation can rule out acute myocardial infarction (AMI), but the ability to identify patients at low risk of 30-day major adverse cardiac events (MACE) is less clear. This study examines the sensitivity of low concentrations of hs-cTnT on presentation to rule out 30-day MACE.

Methods: This prospective cohort study enrolled patients with chest pain presenting to the emergency department with nonischemic electrocardiograms who underwent AMI rule-out with an hs-cTnT assay.

Rising above helium: A hydrogen carrier gas chromatography flame ionization detection (GC-FID) method for the simultaneous quantification of toxic alcohols and ethylene glycol in human plasma specimens.

Unlabelled: Here we validate a GC, Flame Ionization Detection (GC-FID), liquid injection method using hydrogen as a carrier gas combining analysis of toxic volatile alcohols (VA): methanol, ethanol, isopropanol, acetone, as well as glycols, ethylene glycol (EG) and propylene glycol (PG), in a single method.

Methodology: 200 μL of calibrator, QC, or patient specimen were deproteinized with 400 μL of acetonitrile containing internal standards (10 mmol/L N-propyl alcohol for VA and 2.5 mmol/L 1,2-butanediol for glycols).

Urine protein detection by dipstick: No interference from alkalinity or specific gravity.

Tetrabromphenol blue dye based methods are used to detect proteinuria using urinalysis dipsticks. Manufacturers have claimed that alkalinity leads to false positive proteinuria, and that high specific gravity leads to false negative protein results. However, published reports describing this phenomenon remain equivocal.

Sex-specific, high-sensitivity cardiac troponin T cut-off concentrations for ruling out acute myocardial infarction with a single measurement.

Objective: Sex-specific diagnostic cut-offs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction (MI). The objective of this study was to quantify test characteristics of sex-specific cut-offs of a single, high-sensitivity cardiac troponin T (hs-cTnT) assay for 7-day MI in patients with chest pain.

Methods: This observational cohort study included consecutive emergency department (ED) patients with suspected cardiac chest pain from four Canadian EDs who had an hs-cTnT assay performed within 60 minutes of ED arrival.

Stabilizing specimens for routine ammonia testing in the clinical laboratory.

Background: In vitro deamination generates ammonia in freshly collected blood specimens. To prevent this, samples for ammonia testing are usually collected on ice and run rapidly (e.g.

Comparative Evaluation of 2-Hour Rapid Diagnostic Algorithms for Acute Myocardial Infarction Using High-Sensitivity Cardiac Troponin T.

Background: Symptoms of acute coronary syndrome account for a large proportion of emergency department (ED) visits and hospitalizations. High-sensitivity troponin can rapidly rule out or rule in acute myocardial infarction (AMI) within a short time of ED arrival. We sought to validate test characteristics and classification performance of 2-hour high-sensitivity troponin T (hsTnT) algorithms for the rapid diagnosis of AMI.

Undetectable Concentrations of a Food and Drug Administration-approved High-sensitivity Cardiac Troponin T Assay to Rule Out Acute Myocardial Infarction at Emergency Department Arrival.

Background: The objective of this study was to quantify the sensitivity of very low concentrations of high-sensitivity cardiac troponin T (hsTnT) at ED arrival for acute myocardial infarction (AMI) in a large cohort of chest pain patients evaluated in real-world clinical practice.

Methods: This retrospective study included consecutive ED patients with suspected cardiac chest pain evaluated in four urban EDs, excluding those with ST-elevation AMI, cardiac arrest or abnormal kidney function. The primary outcomes were AMI at 7, 30, and 90 days.

One-step extraction and quantitation of toxic alcohols and ethylene glycol in plasma by capillary gas chromatography (GC) with flame ionization detection (FID).

Objectives: Clinical analysis of volatile alcohols (i.e. methanol, ethanol, isopropanol, and metabolite acetone) and ethylene glycol (EG) generally employs separate gas chromatography (GC) methods for analysis.

Evaluation of a third party enzymatic ammonia method for use on the Roche Cobas 6000 (c501) automated platform.

Objective: Adaptation of the Randox Enzymatic Manual UV Ammonia method to be used on the Roche Cobas 6000 (c501) automated analyzer platform.

Design And Methods: The Randox ammonia reagent was evaluated for precision, linearity, accuracy and interference from hemolysis, icterus and lipemia on the Roche c501 analyzer. Comparison studies were conducted for the Randox reagent between Roche c501, Siemens Vista, Ortho Vitros 250, and Beckman DxC methods.

Co-overexpression of Met and hepatocyte growth factor promotes systemic metastasis in NCI-H460 non-small cell lung carcinoma cells.

Complete resection of early-stage non-small cell lung cancer (NSCLC) is potentially curative, yet approximately 50% of patients are at risk for developing metastatic recurrence. Met, the receptor for hepatocyte growth factor (HGF) is a receptor tyrosine kinase with demonstrated roles in regulating cellular proliferation, motility, morphogenesis, and apoptosis. Met receptor and its ligand, HGF, are commonly overexpressed in NSCLC, and their overexpression has been associated with poor prognosis, which could potentially involve a paracrine and/or autocrine activation loop.

Evaluation of a point-of-care glucose meter for general use in complex tertiary care facilities.

Objective: To evaluate the performance of the StatStrip glucose meter from Nova Biomedical for use in complex tertiary care facilities.

Methods: Performance evaluation was conducted in 6 clinical locations involving nurse end-users. Imprecision (CV)<5% was considered acceptable.