Performance of a Norfentanyl Immunoassay in Specimens with Low Concentrations of Fentanyl and/or Norfentanyl

BACKGROUND

Many fentanyl immunoassays are limited in their ability to detect norfentanyl. Urine specimens collected from individuals who have been exposed to fentanyl frequently have detectable concentrations of norfentanyl (≥2 ng/mL) but low concentrations of fentanyl (<2 ng/mL) by LC-MS/MS. The Lin-Zhi Fentanyl II Immunoassay (Lin-Zhi) claims 100% cross-reactivity with norfentanyl and therefore may detect exposure missed by other assays.

METHODS

In addition to verifying the manufacturer's analytical sensitivity claims, we selected 92 urine specimens with low-positive Lin-Zhi results (1-99 absorbance units, lowest 10%) for analysis by the Immunalysis Health Equity Impact Assessment and ARK II fentanyl methods. The accuracy of the 3 immunoassays was compared to LC-MS/MS as the reference method.

RESULTS

Spiking studies using purified fentanyl and norfentanyl and a set of 100 consecutive specimens confirmed the manufacturer's claims of limit of detection for fentanyl (3.8 ng/mL) and norfentanyl (5.0 ng/mL). However, the 92 low-positive patient specimens demonstrated concentrations of norfentanyl and fentanyl below 2.0 ng/mL by LC-MS/MS, with 47 (51%) having only norfentanyl detected. When comparing Lin-Zhi to the Immunalysis and ARK II immunoassays, only 27 (29%) of the 92 specimens were concordant. Fifty-two (57%) of the specimens were positive by LC-MS/MS and Lin-Zhi but false negative by one or both other immunoassays. Seven specimens (8%) were positive by Lin-Zhi but negative by the other immunoassays and had undetectable concentrations (<2 ng/mL) of fentanyl and norfentanyl by LC-MS/MS.

CONCLUSIONS

The clinical sensitivity of the Lin-Zhi exceeds the manufacturer's claims, providing results comparable to LC-MS/MS methods.

Clinician Ordering and Management Patterns of Urine Toxicology Results at a Cancer Center

CONTEXT

Opioid therapy is a cornerstone for treatment of cancer-related pain, but standardized management practices for patients with cancer and aberrant urine drug test (UDT) results are lacking.

OBJECTIVES

To identify the prevalence of UDT ordering (both screening and definitive testing) in the oncology setting and to examine clinician management practices for patients with cancer on opioid therapy with aberrant definitive UDT results.

METHODS

We conducted a retrospective chart review of patients with cancer on opioid therapy at an academic cancer center in the United States. Outcomes included UDT ordering patterns and clinician management practices in response to aberrant definitive UDT results.

RESULTS

Our study revealed an overallUDT ordering rate of 3.7% among 10,371 patients with cancer on opioid therapy. Among 143 patients for whom definitive UDTs were ordered, oncologists only ordered 14 (9.8%) UDTs, while palliative care ordered the majority (n=129; 90.2%). Fifty-five (38.5%) patients had aberrant results, and the most common aberrancy was presence of illicit drugs [22 (15.4%)]. Clinicians rarely made medication changes [20 (36.4%)] when UDT results were aberrant, and in the setting of possible fentanyl use (n=8), only 3 (37.5%) patients were started/switched to methadone, and none were started/switched to buprenorphine.

CONCLUSION

Overall UDT ordering was infrequent for patients with cancer on opioid therapy, especially by oncologists, and clinicians rarely make prescribing changes when definitive UDT results were aberrant. More definitive guidance related to UDT ordering and opioid management are needed for patients with cancer and aberrant UDT results.

Large-Scale Scientific Study Led by a Professional Organization during the COVID-19 Pandemic: Operations, Best Practices, and Lessons Learned

In 2021, the Association for Diagnostics & Laboratory Medicine (ADLM) (formerly the American Association for Clinical Chemistry [AACC]) developed a scientific study that aimed to contribute to the understanding of SARS-CoV-2 immunity during the evolving course of the pandemic. This study was led by a group of expert member volunteers and resulted in survey data from 975 individuals and blood collection from 698 of those participants. This paper describes the formulation and execution of this large-scale scientific study, encompassing best practices and insights gained throughout the endeavor.

Performance of Three Anti-SARS-CoV-2 Anti-S and One Anti-N Immunoassays for the Monitoring of Immune Status and Vaccine Response

This study aimed to evaluate and compare the performance of three anti-S and one anti-N assays that were available to the project in detecting antibody levels after three commonly used SARS-CoV-2 vaccines (Pfizer, Moderna, and Johnson & Johnson). It also aimed to assess the association of age, sex, race, ethnicity, vaccine timing, and vaccine side effects on antibody levels in a cohort of 827 individuals. In September 2021, 698 vaccinated individuals donated blood samples as part of the Association for Diagnostics & Laboratory Medicine (ADLM) COVID-19 Immunity Study. These individuals also participated in a comprehensive survey covering demographic information, vaccination status, and associated side effects. Additionally, 305 age- and gender-matched samples were obtained from the ADLM 2015 sample bank as pre-COVID-19-negative samples. All these samples underwent antibody level analysis using three anti-S assays, namely Beckman Access SARS-CoV-2 IgG (Beckman assay), Ortho Clinical Diagnostics VITROS Anti-SARS-CoV-2 IgG (Ortho assay), Siemens ADVIA Centaur SARS-CoV-2 IgG (Siemens assay), and one anti-N antibody assay: Bio-Rad Platelia SARS-CoV-2 Total Ab assay (BioRad assay). A total of 827 samples (580 COVID-19 samples and 247 pre-COVID-19 samples) received results for all four assays and underwent further analysis. Beckman, Ortho, and Siemens anti-S assays showed an overall sensitivity of 99.5%, 97.6%, and 96.9%, and specificity of 90%, 100%, and 99.6%, respectively. All three assays indicated 100% sensitivity for individuals who received the Moderna vaccine and boosters, and over 99% sensitivity for the Pfizer vaccine. Sensitivities varied from 70.4% (Siemens), 81.5% (Ortho), and 96.3% (Beckman) for individuals who received the Johnson & Johnson vaccine. BioRad anti-N assays demonstrated 46.2% sensitivity and 99.25% specificity based on results from individuals with self-reported infection. The highest median anti-S antibody levels were measured in individuals who received the Moderna vaccine, followed by Pfizer and then Johnson & Johnson vaccines. Higher anti-S antibody levels were significantly associated with younger age and closer proximity to the last vaccine dose but were not associated with gender, race, or ethnicity. Participants with higher anti-S levels experienced significantly more side effects as well as more severe side effects (e.g., muscle pain, chills, fever, and moderate limitations) (p < 0.05). Anti-N antibody levels only indicated a significant correlation with headache. This study indicated performance variations among different anti-S assays, both among themselves and when analyzing individuals with different SARS-CoV-2 vaccines. Caution should be exercised when conducting large-scale studies to ensure that the same platform and/or assays are used for the most effective interpretation of the data.

Robust Response of the Clinical Laboratory to the COVID-19 Pandemic despite Significant Challenges

BACKGROUND

Clinical laboratories immediately provided rapid, reliable, and high-throughout diagnostic testing for COVID-19, which was an essential component in combating the pandemic. As the pandemic evolved, the clinical laboratory was faced with additional challenges. However, there are limited studies on the impact of the pandemic on the clinical laboratory over the past 3 years.

METHODS

The American Association for Clinical Chemistry (AACC) sent 8 surveys over a 32-month time period to international clinical laboratory leadership asking questions about COVID-19 testing, supplies, staffing, and lessons learned.

RESULTS

There were a total of 191 unique respondents: 133 laboratories in the US and 58 laboratories from 37 other countries participated. By May 2020, more than 70% of laboratories offered COVID-19 diagnostic testing with average turnaround times ranging from 1 to 24 h. Daily COVID-19 testing volumes peaked in January of 2022 at a median of 775 tests per day. Throughout the pandemic, supplies and staffing concerns increased. In most of the 8 surveys, 55% to 65% of laboratories reported they were unable to obtain supplies. Obtaining reagents and test kits was the most problematic. Staffing challenges continue to be a significant concern and most laboratories have struggled hiring testing personnel.

CONCLUSIONS

Survey results were utilized to demonstrate the impact of the pandemic on the clinical laboratory community, and importantly, findings were presented to the White House Coronavirus Taskforce. Overall, the clinical laboratories had a robust response to the COVID-19 pandemic, and despite ongoing and evolving challenges, continue to provide rapid diagnostic testing.

Cannabis positivity rates in 17 emergency departments across the United States with varying degrees of marijuana legalization

BACKGROUND

Many states in the United States have progressed towards legalization of marijuana including decriminalization, medicinal and/or recreational use. We studied the impact of legalization on cannabis-related emergency department visits in states with varying degrees of legalization.

METHODS

Seventeen healthcare institutions in fifteen states (California, Colorado, Connecticut, Florida, Iowa, Kentucky, Maryland, Massachusetts, Missouri, New Hampshire, Oregon, South Carolina, Tennessee, Texas, Washington) participated. Cannabinoid immunoassay results and cannabis-related International Classification of Diseases (ninth and tenth versions) codes were obtained for emergency department visits over a 3- to 8-year period during various stages of legalization: no state laws, decriminalized, medical approval before dispensaries, medical dispensaries available, recreational approval before dispensaries and recreational dispensaries available. Trends and monthly rates of cannabinoid immunoassay and cannabis-related International Classification of Diseases code positivity were determined during these legalization periods.

RESULTS

For most states, there was a significant increase in both cannabinoid immunoassay and International Classification of Diseases code positivity as legalization progressed; however, positivity rates differed. The availability of dispensaries may impact positivity in states with medical and/or recreational approval. In most states with no laws, there was a significant but smaller increase in cannabinoid immunoassay positivity rates.

CONCLUSIONS

States may experience an increase in cannabis-related emergency department visits with progression toward marijuana legalization. The differences between states, including those in which no impact was seen, are likely multifactorial and include cultural norms, attitudes of local law enforcement, differing patient populations, legalization in surrounding states, availability of dispensaries, various ordering protocols in the emergency department, and the prevalence of non-regulated cannabis products.

T Cell Responses Correlate with Self-Reported Disease Severity and Neutralizing Antibody Responses Predict Protection against SARS-CoV-2 Breakthrough Infection

OBJECTIVES

The objective of this prospective study was to investigate the role of adaptive immunity in response to SARS-CoV-2 vaccines.

DESIGN AND METHODS

A cohort of 677 vaccinated individuals participated in a comprehensive survey of their vaccination status and associated side effects, and donated blood to evaluate their adaptive immune responses by neutralizing antibody (NAb) and T cell responses. The cohort then completed a follow-up survey to investigate the occurrence of breakthrough infections.

RESULTS

NAb levels were the highest in participants vaccinated with Moderna, followed by Pfizer and Johnson & Johnson. NAb levels decreased with time after vaccination with Pfizer and Johnson & Johnson. T cell responses showed no significant difference among the different vaccines and remained stable up to 10 months after the study period for all vaccine types. In multivariate analyses, NAb responses (<95 U/mL) predicted breakthrough infection, whereas previous infection, the type of vaccine, and T cell responses did not. T cell responses to viral epitopes (<0.120 IU/mL) showed a significant association with the self-reported severity of COVID-19 disease.

CONCLUSION

This study provides evidence that NAb responses to SARS-CoV-2 vaccination correlate with protection against infection, whereas the T cell memory responses may contribute to protection against severe disease but not against infection.

Estimated GFR With Cystatin C and Creatinine in Clinical Practice: A Retrospective Cohort Study

Rationale & Objective

Estimation of glomerular filtration rate (eGFR) and staging of chronic kidney disease (CKD) are essential to guide management. Although creatinine is routinely used, a recent national task force recommended the use of cystatin C for confirmation. The objective of this study was to examine the following parameters: (1) how cystatin C correlates with creatinine eGFR; (2) how it indicates differences in CKD staging; and (3) how it may affect kidney care delivery.

Study Design

Retrospective observational cohort study.

Setting & Participants

1,783 inpatients and outpatients who had cystatin C and creatinine levels drawn within 24 hours at Brigham Health-affiliated clinical laboratories.

Predictors

Serum creatinine levels, basic clinical/sociodemographic variables, and reasons for ordering cystatin C from a structured partial chart review.

Analytical Approach

Univariate and multivariable linear and logistic regression.

Results

Cystatin C-based eGFR was very strongly correlated with creatinine-based eGFR (Spearman correlation ρ = 0.83). Cystatin C eGFR resulted in a change to a later CKD stage in 27%, an earlier stage in 7%, and no change in 66% of patients. Black race was associated with a lower likelihood of change to a later stage (OR, 0.53; 95% CI [0.36, 0.75]; P < 0.001), whereas age (OR per year OR, 1.03; 95% CI [1.02, 1.04]; P < 0.001) and Elixhauser score (OR per point OR, 1.22; 95% CI [1.10, 1.36]; P < 0.001) were associated with a higher likelihood of change to a later stage.

Limitations

Single center, no direct measurement of clearance for comparison, and inconsistent self-identification of race/ethnicity.

Conclusions

Cystatin C eGFR correlates strongly with creatinine eGFR but can have a substantial effect on CKD staging. As cystatin C is adopted, clinicians must be informed on this impact.

Tolerance for three commonly administered COVID-19 vaccines by healthcare professionals

Importance

Most healthcare institutions require employees to be vaccinated against SARS-CoV-2 and many also require at least one booster.

Objective

We determine the impact of vaccine type, demographics, and health conditions on COVID-19 vaccine side effects in healthcare professionals.

Design

A COVID-19 immunity study was performed at the 2021 American Association for Clinical Chemistry Annual Scientific meeting. As part of this study, a REDCap survey with cascading questions was administered from September 9, 2021 to October 20, 2021. General questions included participant demographics, past and present health conditions, smoking, exercise, and medications. COVID-19 specific questions asked about SARS-CoV-2 vaccine status and type, vaccine-associated side effects after each dose including any boosters, previous infection with COVID-19, diagnostic testing performed, and type and severity symptoms of COVID-19.

Results

There were 975 participants (47.1% male, median age of 50 years) who completed the survey. Pfizer was the most commonly administered vaccine (56.4%) followed by Moderna (32.0%) and Johnson & Johnson (7.1%). There were no significant differences in vaccine type received by age, health conditions, smoking, exercise, or type or number of prescription medications. Side effects were reported more frequently after second dose (e.g., Moderna or Pfizer) (54.1%) or single/only dose of Johnson & Johnson (47.8%). Males were significantly more likely to report no side effects (p < 0.001), while females were significantly more likely to report injection site reactions (p < 0.001), fatigue (p < 0.001), headache (p < 0.001), muscle pain (p < 0.001), chills (p = 0.001), fever (p = 0.007), and nausea (p < 0.001). There was a significant upward trend in participants reporting no side effects with increasing age (p < 0.001). There were no significant trends in side effects among different races, ethnicities, health conditions, medications, smoking status or exercise. In multivariate logistic regressions analyses, the second dose of Moderna was associated with a significantly higher risk of side effects than both the second dose of Pfizer and the single dose of Johnson & Johnson.

Conclusions and relevance

Younger people, females, and those receiving the second dose of Moderna had more COVID-19 vaccine side effects that per self-report led to moderate to severe limitations. As reported in other studies, the increase in side effects from Moderna may be explained by higher viral mRNA concentrations but be associated with additional protective immunity.

Glucose Meter Standardization Across a Large Academic Hospital System

BACKGROUND

To select and standardize point-of-care (POC) glucose meters across a multi-hospital system.

METHODS

We formed a multidisciplinaryPOC glucose standardization working group includingkey stakeholders from each site. A set ofselectioncriteria: usability, clinical and laboratory performance, indications for use, interface connectivity, ease of implementation and ongoing operational costs were used to develop ascoring schemato facilitate a consensus-driven selection process.

RESULTS

Method comparison and consensus error grid evaluation against the clinically validated reference methods demonstrated that the analytical performance for all candidate meters was comparable for both the laboratory and clinical evaluation. However, Meter 1 ranked highest in usability evaluations, implementation and streamlined interface connectivity. The meter selection process and implementation were staggered across sites due to complexity of transitioning to a new manufacturer's meter and limitations in vendor support for training and ongoing troubleshooting of interface connectivity.

CONCLUSIONS

Standardization of POC glucose meters in a large multi-hospital system is a complex undertaking requiring robust, multidisciplinary organizational structure both system-wide and locally, development of consensus-driven selection tools, usability evaluation by end-users, laboratory and clinical evaluation of the analytical performance, and a strong vendor-laboratory partnership during the implementation process.

Pandemic Response in the Clinical Laboratory: The Utility of Interactive Dashboards

The ability to access and analyze data is critical to manage a laboratory and respond and adapt to changes, particularly during a pandemic. Data analytic tools can not only improve laboratory operations, but also increase the visibility of the laboratory in the healthcare system and demonstrate the positive impact of the laboratory on patient care. In this article, we describe the creation and utility of laboratory dashboards. Several dashboards were designed to assist with pandemic response. For each dashboard, a stored procedure was created that performed a SQL query of our laboratory information system mirror database. We utilized the business analytics platform, Tableau, for data visualization. Users could modify the data by selecting a specific date range, time window, work shift, institution(s), specific test(s), and/or testing platform(s). Access was controlled by OKTA integration to the host server over the web, behind the hospital firewall. During the April 2020 surge, we saw an increase in blood gas testing and corresponding decrease in non-critical testing such as Vitamin D. At our institution, SARS-CoV-2 molecular testing was performed using four primary platforms, four in-house and one send-out. Weekly and hourly testing volumes as well as turnaround times fluctuated based on reagent availability, new testing requests, staffing, and operational changes. Productivity dashboards indicated that coagulation testing volumes were highest on the third shift and that all three analyzers may not be necessary. Further, specimen volumes and productivity of accessioning staff varied throughout the day. Phlebotomy venipuncture volumes and patient wait times also varied throughout the pandemic. A decrease in ambulatory draws was seen during the surge but after reopening draw volumes, particularly at offsite locations, surpassed prepandemic volumes. We demonstrate that data analytics and interactive dashboards are powerful tools, are helpful in response to a pandemic and lead to improved TAT, supply utilization, staffing and workflows. Furthermore, dashboards provide objective data to review with hospital leadership and promote collaboration.

Limited Evidence for Use of a Black Race Modifier in eGFR Calculations: A Systematic Review

Background

Commonly used estimated glomerular filtration rate (eGFR) equations include a Black race modifier (BRM) that was incorporated during equation derivation. Race is a social construct, and a poorly characterized variable that is applied inconsistently in clinical settings. The BRM results in higher eGFR for any creatinine concentration, implying fundamental differences in creatinine production or excretion in Black individuals compared to other populations. Equations without inclusion of the BRM have the potential to detect kidney disease earlier in patients at the greatest risk of chronic kidney disease (CKD), but also has the potential to over-diagnose CKD or impact downstream clinical interventions. The purpose of this study was to use an evidence- based approach to systematically evaluate the literature relevant to the performance of the eGFR equations with and without the BRM and to examine the clinical impact of the use or removal.

Content

PubMed and Embase databases were searched for studies comparing measured GFR to eGFR in racially diverse adult populations using the Modification of Diet in Renal Disease or the 2009-Chronic Kidney Disease Epidemiology Collaboration-creatinine equations based on standardized creatinine measurements. Additionally, we searched for studies comparing clinical use of eGFR calculated with and without the BRM. 8,632 unique publications were identified; an additional 3 studies were added post-hoc. In total, 96 studies were subjected to further analysis and 44 studies were used to make a final assessment.

Summary

There is limited published evidence to support the use of a BRM in eGFR equations.

Rates of Fentanyl Positivity in Neonatal Urine Following Maternal Analgesia During Labor and Delivery

BACKGROUND

Fentanyl is commonly given as an analgesic during labor and delivery. The extent of transplacental drug transfer and fetal exposure is not well studied. We analyzed the relationship between neonatal urine fentanyl results and various peripartum factors.

METHODS

A total of 96 neonates with urine toxicology screening between January 2017 and September 2018 were included in the study. Medical record review was used to obtain maternal, neonatal, and anesthesia parameters. A subset of 9 specimens were further tested for levels of fentanyl and norfentanyl by liquid chromatography-tandem mass spectrometry.

RESULTS

In 29% (n = 24) of cases associated with fentanyl-containing labor analgesia, neonatal toxicology screens were positive for the presence of fentanyl. Positive test results strongly correlated with the cumulative dose and duration of labor analgesia (P < 0.001). The odds of positive neonatal fentanyl screen results increased 4-fold for every 5 hours of maternal exposure to labor analgesia. Importantly, however, neonatal outcomes for infants with positive and negative urine fentanyl screens were the same.

CONCLUSIONS

Our study establishes that maternal fentanyl analgesia is strongly associated with positive neonatal urine fentanyl screens and suggests that more judicious use of these laboratory tests may be warranted.

Traumatic pedestrian and bicyclist injuries associated with intoxication

BACKGROUND

Drug and alcohol use are risk factors for trauma among operators of motor vehicles and contribute to trauma in pedestrians and bicyclists. We describe the prevalence of drug and alcohol use and clinical consequences in a cohort of pedestrians and bicyclists with trauma.

METHODS

We analyzed a 25-month data set of 916 trauma team activations from January 2017-January 2019 at an urban, level I trauma center. Blood ethanol levels and urine toxicology screens were obtained in 94 pedestrian and bicyclist trauma activations. We compared pedestrians or bicyclists with a positive urine or blood screen (n = 69) to those with negative screens (n = 25). We conducted a retrospective chart review to determine mechanism of injury, injury pattern, and disposition from the emergency department (ED).

RESULTS

Overall, 38 (55%) of injured patients with positive screen were pedestrians and 31 (45%) were bicyclists. Fentanyl was the most commonly detected drug (n = 38; 40%), followed by opiates (n = 27; 29%), and tetrahydrocannabiol (THC) (n = 23; 25%). Twenty-one patients were positive for ethanol. Pedestrians and bicyclists with positive toxicology screens were significantly more likely to sustain fractures (p < .01), require an operative procedure (p < .05), or intensive care unit admission (p < .05).

CONCLUSION

Our study builds on previous literature which suggests that intoxicated bicyclists and pedestrians suffer frequent and more severe injury than their sober counterparts. Public health campaigns should educate bicyclists and pedestrians about the risks of cycling or walking in areas of road traffic while under the influence of alcohol or illicit drugs.

How SARS-CoV-2 Transformed the Clinical Laboratory: Challenges and Lessons Learned

The COVID-19 pandemic has made a devastating impact on global health and continues to challenge healthcare infrastructure and delivery. The clinical laboratories were no exception as they are responsible for diagnostic testing that dictates many clinical, infection control and public health decisions. Information technology and laboratory management tools are critical assets for maintaining and adapting operations in response to crises and when utilized effectively, promote the integration between the clinical laboratory specialties (e.g., chemistry, hematology, microbiology, and molecular pathology). During the COVID-19 pandemic, our systems and processes were strained due to high testing volumes, demand for rapid turnaround times, supply chain constraints, and constantly evolving testing algorithms and result interpretations as our knowledge of the virus and of diagnostics increased over time. In this report, we describe those challenges and subsequent adaptations made by each clinical laboratory section. We hope these details help provide potential solutions and approaches for other hospitals facing COVID-19 surges or other future pandemics.

Therapeutic Drug Monitoring of Second- and Third-Generation Antiepileptic Drugs: Insights From a College of American Pathologists Proficiency Testing Survey

CONTEXT.—

Therapeutic drug monitoring has traditionally been widely used for first-generation antiepileptic drugs (AEDs) such as carbamazepine and phenytoin. The last 2 decades have seen the introduction of second- and third-generation AEDs (eg, lamotrigine, levetiracetam, and topiramate) into clinical practice.

OBJECTIVE.—

To use data from the College of American Pathologists Therapeutic Drug Monitoring, Extended proficiency testing survey to determine the performance of assays used for therapeutic drug monitoring of newer AEDs, including comparison of enzyme immunoassay and chromatographic techniques.

DESIGN.—

Six years of proficiency testing surveys were reviewed (2013-2018).

RESULTS.—

Steady growth was seen in participant volumes for newer AEDs. The analytical performance of automated enzyme immunoassays for lamotrigine, levetiracetam, and topiramate was similar to that of chromatographic methods, consistent with published literature using patient samples for comparisons. The majority of participating laboratories now use enzyme immunoassays to measure levetiracetam.

CONCLUSIONS.—

Survey results reflect steadily growing interest in therapeutic drug monitoring of newer AEDs. The increasing availability of robust immunoassays for new AEDs should facilitate their clinical utility, especially for clinical laboratories that do not perform chromatographic assays for therapeutic drug monitoring.

Laboratory-Generated Urine Toxicology Interpretations: A Mixed Methods Study

BACKGROUND

Clinicians frequently order urine drug testing (UDT) for patients on chronic opioid therapy (COT), yet often have difficulty interpreting test results accurately.

OBJECTIVES

To evaluate the implementation and effectiveness of a laboratory-generated urine toxicology interpretation service for clinicians prescribing COT.

STUDY DESIGN

Type II hybrid-convergent mixed methods design (implementation) and pre-post prospective cohort study with matched controls (effectiveness).

SETTING

Four ambulatory sites (2 primary care, 1 pain management, 1 palliative care) within 2 US academic medical institutions.

METHODS

Interpretative reports were generated by the clinical chemistry laboratory and were provided to UDT ordering providers via inbox message in the electronic health record (EHR). The Partners Institutional Review Board approved this study.Participants were primary care, pain management, and palliative care clinicians who ordered liquid chromatography-mass spectrometry UDT for COT patients in clinic. Intervention was a laboratory-generated interpretation service that provided an individualized interpretive report of UDT results based on the patient's prescribed medications and toxicology metabolites for clinicians who received the intervention (n = 8) versus matched controls (n = 18).Implementation results included focus group and survey feedback on the interpretation service's usability and its impact on workflow, clinical decision making, clinician-patient relationships, and interdisciplinary teamwork. Effectiveness outcomes included UDT interpretation concordance between the clinician and laboratory, documentation frequency of UDT results interpretation and communication of results to patients, and clinician prescribing behavior at follow-up.

RESULTS

Among the 8 intervention clinicians (median age 58 [IQR 16.5] years; 2 women [25%]) on a Likert scale from 1 ("strongly disagree") to 5 ("strongly agree"), 7 clinicians reported at 6 months postintervention that the interpretation service was easy to use (mean 5 [standard deviation {SD}, 0]); improved results comprehension (mean 5 [SD, 0]); and helped them interpret results more accurately (mean 5 [SD, 0]), quickly (mean 4.67 [SD, 0.52]), and confidently (mean 4.83 [SD, 0.41]). Although there were no statistically significant differences in outcomes between cohorts, clinician-laboratory interpretation concordance trended toward improvement (intervention 22/32 [68.8%] to 29/33 [87.9%] vs. control 21/25 [84%] to 23/30 [76.7%], P = 0.07) among cases with documented interpretations.

LIMITATIONS

This study has a low sample size and was conducted at 2 large academic medical institutions and may not be generalizable to community settings.

CONCLUSIONS

Interpretations were well received by clinicians but did not significantly improve laboratory-clinician interpretation concordance, interpretation documentation frequency, or opioid-prescribing behavior.

Comparison of Oral Fluid and Urine for Detection of Cocaine Abuse Using Liquid Chromatography with Tandem Mass Spectrometry

BACKGROUND

Requests for urine (UR) and oral fluid (OF) drug testing at our institutions are increasing. However, few studies have assessed the accuracy of each matrix using paired specimens and LC-MS/MS. We compared OF and UR for detection of cocaine (COC) abuse in addiction medicine-psychiatry (AMP) clinics.

METHODS

We measured COC and benzoylecgonine (BZE) in OF (limit of detection (LOD) 2.0 µg/L) and BZE in UR (LOD 5 µg/L) by LC-MS/MS in 258 paired samples, and compared the two matrices when higher UR cutoffs of 25, 50, and 150 µg/L were employed.

RESULTS

UR detected more COC abuse than OF at the LOD (5 µg/L). BZE was detected in 63 UR specimens and COC and/or BZE in 40 OF specimens (29 OF+UR+, 11 OF+UR-, 34 OF-UR+). UR creatinine was lower in OF+UR- specimens. COC and BZE were detected in 88% (35/40) and 75% (30/40) of OF specimens, respectively. OF was equivalent to UR at detecting COC abuse using a 25 µg/L cutoff, and detected more COC abuse than UR using 50 and 150 µg/L cutoffs. The ratio of OF COC/BZE increased with decreasing UR BZE concentrations.

CONCLUSIONS

We demonstrate that OF detects more COC abuse in an AMP setting when UR BZE cutoffs ≥ 50 µg/L are utilized, and that UR creatinine concentrations are significantly lower in specimens positive for COC and/or BZE in OF and negative for BZE in UR. The presence of only COC in OF and low concentrations of UR BZE likely indicates remote use of COC.

Provider Misinterpretation, Documentation, and Follow-Up of Definitive Urine Drug Testing Results

BACKGROUND

Urine drug testing (UDT) is an essential tool to monitor opioid misuse among patients on chronic opioid therapy. Inaccurate interpretation of UDT can have deleterious consequences. Providers' ability to accurately interpret and document UDT, particularly definitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) results, has not been widely studied.

OBJECTIVE

To examine whether providers correctly interpret, document, and communicate LC-MS/MS UDT results.

DESIGN

This is a retrospective chart review of 160 UDT results (80 aberrant; 80 non-aberrant) between August 2017 and February 2018 from 5 ambulatory clinics (3 primary care, 1 oncology, 1 pain management). Aberrant results were classified into one or more of the following categories: illicit drug use, simulated compliance, not taking prescribed medication, and taking a medication not prescribed. Accurate result interpretation was defined as concordance between the provider's documented interpretation and an expert laboratory toxicologist's interpretation. Outcome measures were concordance between provider and laboratory interpretation of UDT results, documentation of UDT results, results acknowledgement in the electronic health record, communication of results to the patient, and rate of prescription refills.

KEY RESULTS

Aberrant results were most frequently due to illicit drug use. Overall, only 88 of the 160 (55%) had any documented provider interpretations of which 25/88 (28%) were discordant with the laboratory toxicologist's interpretation. Thirty-six of the 160 (23%) documented communication of the results to the patient. Communicating results was more likely to be documented if the results were aberrant compared with non-aberrant (33/80 [41%] vs. 3/80 [4%], p < 0.001). In all cases where provider interpretations were discordant with the laboratory interpretation, prescriptions were refilled.

CONCLUSIONS

Erroneous provider interpretation of UDT results, infrequent documentation of interpretation, lack of communication of results to patients, and prescription refills despite inaccurate interpretations are common. Expert assistance with urine toxicology interpretations may be needed to improve provider accuracy when interpreting toxicology results.

Significant Operational Improvements with Implementation of Next Generation Laboratory Automation

OBJECTIVES

To investigate the benefits and challenges of introducing next generation chemistry and coagulation automation.

METHODS

We replaced the Roche modular preanalytic system attached to Roche Cobas 6000 analyzers with the Roche 8100 preanalytical line attached to the Roche Cobas 8000 and Stago STA R Max analyzers. The system included 2 add-on buffers (AOBs) for automated specimen archival and retrieval and primary-tube specimen processing. We measured turnaround time (TAT) from specimen receipt to result for chemistry and coagulation tests before, during, and after system implementation. TAT for add-on tests was also measured.

RESULTS

We completed the system implementation during a 17-month period using existing laboratory space. The TAT for chemistry, coagulation, and add-on tests decreased significantly (P <.005, P <.001, and P <.005, respectively). We encountered several challenges, including barcode-label errors, mechanical problems, and workflow issues due to lack of bidirectional track for coagulation testing.

CONCLUSIONS

Next generation laboratory automation yielded significantly shortened and less-variable TAT, particularly for add-on testing. Our approach could help other laboratories in the process of implementing and configuring automated systems.

Urine is superior to oral fluid for detecting buprenorphine compliance in patients undergoing treatment for opioid addiction

BACKGROUND

Buprenorphine (BUP) is commonly used in opioid agonist medication-assisted treatment (OA-MAT). Oral fluid (OF) is an attractive option for compliance monitoring during OA-MAT as collections are observed and evidence suggests that OF is less likely to be adulterated than urine (UR). However, the clinical and analytical performance of each matrix for monitoring BUP compliance has not been well studied.

METHODS

We collected 260 paired OF and UR specimens. Concentrations of buprenorphine (BUP) and norbuprenorphine (NBUP) were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in each matrix. The glucuronide metabolites and naloxone concentrations were also measured in UR by LC-MS/MS. Medications were reviewed and UR creatinine concentrations were determined.

RESULTS

147/260 specimens (57%) were positive for BUP and/or metabolites in one or both matrices. BUP and/or metabolites were more likely to be detected in UR (p < 0.001). 1 OF specimen and 12 UR specimens were considered adulterated/substituted. The majority of patients prescribed BUP were positive for BUP in UR (97%) as opposed to OF (78%). The detection of undisclosed use approximately doubled in UR.

CONCLUSIONS

UR is the preferred matrix for detecting both buprenorphine compliance and undisclosed use. Clinicians should consider the ease of collection, risk of adulteration and detection of illicit drug use when deciding on an appropriate matrix. If OF testing is clinically necessary, UR should be measured in conjunction with OF at least periodically to avoid false negative BUP results.

Interpretation and Utility of Drug of Abuse Screening Immunoassays: Insights From Laboratory Drug Testing Proficiency Surveys

Context.—

Urine drug testing is frequently ordered by health care providers. Immunoassays are widely used for drug testing, yet have potential limitations, including variable cross-reactivity. The last decade has seen worsening of a prescription drug abuse epidemic.

Objective.—

To use data from a College of American Pathologists proficiency testing survey, Urine Drug Testing, Screening, to determine and summarize the characteristics, performance, and limitations of immunoassays.

Design.—

Seven years of proficiency surveys were reviewed (2011–2017).

Results.—

Rapid growth was seen in participant volumes for specific immunoassays for synthetic opioids (eg, buprenorphine, fentanyl, oxycodone) and 3,4-methylenedioxymethamphetamine (“ecstasy”). Participant volumes remained high for immunoassays targeting less commonly abused drugs such as barbiturates and phencyclidine. For opiate immunoassays, the number of laboratories using a 2000 ng/mL positive cutoff remained stable, and an increasing number adopted a 100 ng/mL cutoff. Opiate and amphetamine immunoassays showed high variability in cross-reactivity for drugs other than the assay calibrator. Assays targeting a single drug or metabolite generally performed well on drug challenges.

Conclusions.—

Survey results indicate strong clinical interest in urine drug testing and some adoption of new assays. However, urine drug testing availability does not parallel prevailing patterns of drug prescribing and abuse patterns. In particular, specific immunoassays for synthetic opioids and a lower positive cutoff for opiate immunoassays may be underused, whereas immunoassays for barbiturates, methadone, propoxyphene, and phencyclidine may be overused. Laboratories are encouraged to review their test menu, cutoffs, and assay performance and adjust their test offerings based on clinical needs and technical capabilities.

Impact of clinical sample handling and processing on ultra-low level measurements of plasma cytokines

OBJECTIVES

In this study, we evaluated the impact of clinical sample handling and processing on IL-6, IL-10, IFNγ, and IL-2 measurements in plasma.

DESIGN AND METHODS

We collected whole blood samples and analyzed various pre-analytical parameters. We assessed the following: 1) cytokine stability in whole blood that was stored over a ten-hour period at room temperature and 4 °C; 2) cytokine stability in plasma over 6 h; 3) vigorous sample handling including repeated dropping and transport through a pneumatic transport system; and 4) freeze-thaw stability of cytokines in plasma. To ensure ability to measure IL-6, IL-10, IFNγ, and IL-2 levels in plasma, we used Simoa, an ultra-sensitive immunoassay platform.

RESULTS

We show that whole blood storage at room temperature results in decreased cytokine levels and that whole blood storage at 4 °C results in greater cytokine stability. We also show that cytokines are stable when whole blood samples are subjected to vigorous sample handling. Lastly, we show that cytokines are stable in plasma over three freeze-thaw cycles.

CONCLUSIONS

Clinical sample handling and processing can affect measurements of IL-6, IL-10, IFNγ, and IL-2 in plasma. We believe this study will be a useful reference for future studies in which these cytokines are used as potential biomarkers.

Development of a Commercial Reference Laboratory Elective Rotation for Residents in Clinical Pathology

OBJECTIVES

To develop a curriculum for a commercial reference laboratory clinical pathology training elective.

METHODS

A 4-day elective at Quest Diagnostics was developed. The elective included 32 sessions composed of interactive didactic sessions and laboratory tours/demonstrations. Ten residents who attended the elective completed a written evaluation and scored each component of the curriculum.

RESULTS

Written comments were very positive and demonstrated the goals of the elective were achieved. Laboratory tours and one-on-one sessions with the medical directors were especially well received. Most of the residents stated that the rotation gave them exposure to an area of laboratory medicine that they were not familiar with.

CONCLUSIONS

The elective provided a resident training experience that was highly regarded and exposed residents to an area of laboratory medicine not encountered in most pathology training programs. Our curriculum could serve as a model for establishing a similar elective in other training programs.

Quality Control Practices for Chemistry and Immunochemistry in a Cohort of 21 Large Academic Medical Centers

OBJECTIVES

In the United States, minimum standards for quality control (QC) are specified in federal law under the Clinical Laboratory Improvement Amendment and its revisions. Beyond meeting this required standard, laboratories have flexibility to determine their overall QC program.

METHODS

We surveyed chemistry and immunochemistry QC procedures at 21 clinical laboratories within leading academic medical centers to assess if standardized QC practices exist for chemistry and immunochemistry testing.

RESULTS

We observed significant variation and unexpected similarities in practice across laboratories, including QC frequency, cutoffs, number of levels analyzed, and other features.

CONCLUSIONS

This variation in practice indicates an opportunity exists to establish an evidence-based approach to QC that can be generalized across institutions.

The Benefits and Challenges of an Interfaced Electronic Health Record and Laboratory Information System: Effects on Laboratory Processes

Context.—

A recent government regulation incentivizes implementation of an electronic health record (EHR) with computerized order entry and structured results display. Many institutions have also chosen to interface their EHR with their laboratory information system (LIS).

Objective.—

To determine the impact of an interfaced EHR-LIS on laboratory processes.

Design.—

We analyzed several different processes before and after implementation of an interfaced EHR-LIS: the turnaround time, the number of stat specimens received, venipunctures per patient per day, preanalytic errors in phlebotomy, the number of add-on tests using a new electronic process, and the number of wrong test codes ordered. Data were gathered through the LIS and/or EHR.

Results.—

The turnaround time for potassium and hematocrit decreased significantly (P = .047 and P = .004, respectively). The number of stat orders also decreased significantly, from 40% to 7% for potassium and hematocrit, respectively (P &lt; .001 for both). Even though the average number of inpatient venipunctures per day increased from 1.38 to 1.62 (P &lt; .001), the average number of preanalytic errors per month decreased from 2.24 to 0.16 per 1000 specimens (P &lt; .001). Overall there was a 16% increase in add-on tests. The number of wrong test codes ordered was high and it was challenging for providers to correctly order some common tests.

Conclusions.—

An interfaced EHR-LIS significantly improved within-laboratory turnaround time and decreased stat requests and preanalytic phlebotomy errors. Despite increasing the number of add-on requests, an electronic add-on process increased efficiency and improved provider satisfaction. Laboratories implementing an interfaced EHR-LIS should be cautious of its effects on test ordering and patient venipunctures per day.

Significant Reduction in Preanalytical Errors for Nonphlebotomy Blood Draws After Implementation of a Novel Integrated Specimen Collection Module

OBJECTIVES

Most preanalytical errors at our institution occur during nonphlebotomy blood draws. We implemented an electronic health record (EHR), interfaced the EHR to the laboratory information system, and designed a new specimen collection module. We studied the effects of the new system on nonphlebotomy preanalytical errors.

METHODS

We used an electronic database of preanalytical errors and calculated the number and type of the most common errors in the emergency department (ED) and inpatient nursing for 3-month periods before (August-October 2014) and after (August-October 2015) implementation. The level of staff compliance with the new system was also assessed.

RESULTS

The average monthly preanalytical errors decreased significantly from 7.95 to 1.45 per 1,000 specimens in the ED (P < 0001) and 11.75 to 3.25 per 1,000 specimens in inpatient nursing (P < 0001). The rate of decrease was similar for mislabeled, unlabeled, wrong specimen received and no specimen received errors. Most residual errors (80% in the ED and 67% in inpatient nursing) occurred when providers did not use the new system as designed.

CONCLUSIONS

Implementation of a customized specimen collection module led to a significant reduction in preanalytical errors. Improved compliance with the system may lead to further reductions in error rates.

7-aminoclonazepam is superior to clonazepam for detection of clonazepam use in oral fluid by LC-MS/MS

BACKGROUND

Clonazepam (CLON) is not only frequently prescribed in addiction management but is also commonly abused. Therefore many addiction clinics perform oral fluid (OF) testing, which unlike urine is not subject to adulteration, to monitor CLON compliance. However, CLON and other benzodiazepines can be challenging to detect in OF due to their weakly acidic nature and their presence in low concentrations. We determined the optimal technical and clinical approach for the detection of CLON use using OF.

METHODS

We measured CLON and its primary metabolite 7-aminoclonazepam (7AC) by liquid chromatography-tandem mass spectrometry in OF specimens over a 2 month period. The samples were collected using the Orasure Intercept OF sample collection device.

RESULTS

One hundred samples were presumptive-positive for 7AC and/or CLON. 91 (91.0%) confirmed positive for 7AC (median, range: 4.2, 0.5-316.7 ng/ml) using the ion ratio test, while only 44 of the 100 (44.0%) samples confirmed positive for CLON (median, range: 3.7, 0.5-217.2 ng/ml) using the ion ratio test. In OF the levels of 7AC were approximately 2.4-fold higher than CLON. The use of 7AC as an analyte for the detection of both CLON compliance and undisclosed use is also recommended.

CONCLUSIONS

7AC should be the analyte measured in OF for the detection of CLON use.

HIGH-DOSE BIOTIN TREATMENT FOR SECONDARY PROGRESSIVE MULTIPLE SCLEROSIS MAY INTERFERE WITH THYROID ASSAYS

OBJECTIVE

To review cases and increase awareness in clinicians treating patients who may be taking biotin.

METHODS

We describe the presentation and workup of a woman with secondary progressive multiple sclerosis on high dose biotin with laboratory studies suggestive of thyrotoxicosis.

RESULTS

Plasma samples showed laboratory evidence of elevated thyroid hormone levels with elevated free thyroxine >7.8 ng/dl (reference interval (RI) 0.9-1.7 ng/dl) and decreased thyroid stimulating hormone <0.02 uIU/ml (RI 0.50-5.70 uIU/ml). Laboratory values normalized when biotin was withheld prior to repeat testing.

CONCLUSIONS

Our case report demonstrates that ingestion of high dose biotin in multiple sclerosis patients can cause interference with laboratory assessment of thyroid function. This interference causes laboratory values suggestive of thyrotoxicosis and can lead to unnecessary evaluation. Clinicians should be aware of the risk of laboratory interference in this patient demographic.

Optimizing outpatient phlebotomy staffing: tools to assess staffing needs and monitor effectiveness

CONTEXT

Short patient wait times are critical for patient satisfaction with outpatient phlebotomy services. Although increasing phlebotomy staffing is a direct way to improve wait times, it may not be feasible or appropriate in many settings, particularly in the context of current economic pressures in health care.

OBJECTIVE

To effect sustainable reductions in patient wait times, we created a simple, data-driven tool to systematically optimize staffing across our 14 phlebotomy sites with varying patient populations, scope of service, capacity, and process workflows.

DESIGN

We used staffing levels and patient venipuncture volumes to derive the estimated capacity, a parameter that helps predict the number of patients a location can accommodate per unit of time. We then used this parameter to determine whether a particular phlebotomy site was overstaffed, adequately staffed, or understaffed. Patient wait-time and satisfaction data were collected to assess the efficacy and accuracy of the staffing tool after implementing the staffing changes.

RESULTS

In this article, we present the applications of our approach in 1 overstaffed and 2 understaffed phlebotomy sites. After staffing changes at previously understaffed sites, the percentage of patients waiting less than 10 minutes ranged from 88% to 100%. At our previously overstaffed site, we maintained our goal of 90% of patients waiting less than 10 minutes despite staffing reductions. All staffing changes were made using existing resources.

CONCLUSIONS

Used in conjunction with patient wait-time and satisfaction data, our outpatient phlebotomy staffing tool is an accurate and flexible way to assess capacity and to improve patient wait times.

Using Lean principles to optimise inpatient phlebotomy services

BACKGROUND

In the USA, inpatient phlebotomy services are under constant operational pressure to optimise workflow, improve timeliness of blood draws, and decrease error in the context of increasing patient volume and complexity of work. To date, the principles of Lean continuous process improvement have been rarely applied to inpatient phlebotomy.

AIMS

To optimise supply replenishment and cart standardisation, communication and workload management, blood draw process standardisation, and rounding schedules and assignments using Lean principles in inpatient phlebotomy services.

METHODS

We conducted four Lean process improvement events and implemented a number of interventions in inpatient phlebotomy over a 9-month period. We then assessed their impact using three primary metrics: (1) percentage of phlebotomists drawing their first patient by 05:30 for 05:00 rounds, (2) percentage of phlebotomists completing 08:00 rounds by 09:30, and (3) number of errors per 1000 draws.

RESULTS

We saw marked increases in the percentage of phlebotomists drawing their first patient by 05:30, and the percentage of phlebotomists completing rounds by 09:30 postprocess improvement. A decrease in the number of errors per 1000 draws was also observed.

CONCLUSIONS

This study illustrates how continuous process improvement through Lean can optimise workflow, improve timeliness, and decrease error in inpatient phlebotomy. We believe this manuscript adds to the field of clinical pathology as it can be used as a guide for other laboratories with similar goals of optimising workflow, improving timeliness, and decreasing error, providing examples of interventions and metrics that can be tailored to specific laboratories with particular services and resources.

An intervention to improve the timing of vancomycin levels

OBJECTIVES

Blood samples for vancomycin levels are often drawn too early, leading to potential misinterpretation of results. However, only a few studies describe interventions to reduce mistimed vancomycin levels.

METHODS

We implemented an information technology (IT)-based intervention that provided educational instructions to nurses and determined the percentage of levels drawn too early for 27 months before (n = 6,291) and 14 months after (n = 3,608) the intervention. In addition, we conducted nurse interviews (n = 40) and dataset analysis to assess the root causes of mistimed levels.

RESULTS

The percentage of vancomycin timing errors decreased from 39% (2,438/6,291) to 32% (1,137/3,608), though in a time series analysis this decrease was not statistically significant (P = .64). Four common causes of mistimed levels were found: (1) unclear provider orders, (2) scheduling levels to be drawn with morning laboratory tests, (3) lack of communication between providers, and (4) failure to adjust the blood draw in relation to the previous dose.

CONCLUSIONS

A real-time, IT-based intervention that links the timing of levels with medication administration might have a more substantial impact.

The clinical impact of a false-positive urine cocaine screening result on a patient's pain management

BACKGROUND

The urine of a patient admitted for chest and epigastric pain tested positive for cocaine using an immunoassay-based drug screening method (positive/negative cutoff concentration 150 ng/mL). Despite the patient's denial of recent cocaine use, this positive cocaine screening result in conjunction with a remote history of drug misuse impacted the patient's recommended pain therapy. Specifically, these factors prompted the clinical team to question the appropriateness of opioids and other potentially addictive therapeutics during the treatment of cancer pain from previously undetected advanced pancreatic carcinoma.

OBJECTIVE

After pain management and clinical pathology consultation, it was decided that the positive cocaine screening result should be confirmed by gas chromatography-mass spectrometry (GC-MS) testing.

RESULTS

This more sensitive and specific analytical technique revealed that both cocaine and its primary metabolite benzoylecgonine were undetectable (i.e., less than the assay detection limit of 50 ng/mL), thus indicating that the positive urine screening result was falsely positive. With this confirmation, the pain management service team was reassured in offering intrathecal pump (ITP) therapy for pain control. ITP implantation was well tolerated, and the patient eventually achieved excellent pain relief. However, ITP therapy most likely would not have been utilized without the GC-MS confirmation testing unless alternative options failed and extensive vigilant monitoring was initiated.

CONCLUSION

As exemplified in this case, confirmatory drug testing should be performed on specimens with unexpected immunoassay-based drug screening results. To our knowledge, this is the first report of a false-positive urine cocaine screening result and its impact on patient management.

Optimizing urine drug testing for monitoring medication compliance in pain management

BACKGROUND

It can be challenging to successfully monitor medication compliance in pain management. Clinicians and laboratorians need to collaborate to optimize patient care and maximize operational efficiency. The test menu, assay cutoffs, and testing algorithms utilized in the urine drug testing panels should be periodically reviewed and tailored to the patient population to effectively assess compliance and avoid unnecessary testing and cost to the patient.

OBJECTIVE

Pain management and pathology collaborated on an important quality improvement initiative to optimize urine drug testing for monitoring medication compliance in pain management.

METHODS

We retrospectively reviewed 18 months of data from our pain management center. We gathered data on test volumes, positivity rates, and the frequency of false positive results. We also reviewed the clinical utility of our testing algorithms, assay cutoffs, and adulterant panel. In addition, the cost of each component was calculated.

RESULTS

The positivity rate for ethanol and 3,4-methylenedioxymethamphetamine were <1% so we eliminated this testing from our panel. We also lowered the screening cutoff for cocaine to meet the clinical needs of the pain management center. In addition, we changed our testing algorithm for 6-acetylmorphine, benzodiazepines, and methadone. For example, due the high rate of false negative results using our immunoassay-based benzodiazepine screen, we removed the screening portion of the algorithm and now perform benzodiazepine confirmation up front in all specimens by liquid chromatography-tandem mass spectrometry.

CONCLUSION

Conducting an interdisciplinary quality improvement project allowed us to optimize our testing panel for monitoring medication compliance in pain management and reduce cost.

A strategy for optimizing staffing to improve the timeliness of inpatient phlebotomy collections

CONTEXT

The timely availability of inpatient test results is a key to physician satisfaction with the clinical laboratory, and in an institution with a phlebotomy service may depend on the timeliness of blood collections. In response to safety reports filed for delayed phlebotomy collections, we applied Lean principles to the inpatient phlebotomy service at our institution. Our goal was to improve service without using additional resources by optimizing our staffing model.

OBJECTIVE

To evaluate the effect of a new phlebotomy staffing model on the timeliness of inpatient phlebotomy collections.

DESIGN

We compared the median time of morning blood collections and average number of safety reports filed for delayed phlebotomy collections during a 6-month preimplementation period and 5-month postimplementation period.

RESULTS

The median time of morning collections was 17 minutes earlier after implementation (7:42 am preimplementation; interquartile range, 6:27-8:48 am; versus 7:25 am postimplementation; interquartile range, 6:20-8:26 am). The frequency of safety reports filed for delayed collections decreased 80% from 10.6 per 30 days to 2.2 per 30 days.

CONCLUSION

Reallocating staff to match the pattern of demand for phlebotomy collections throughout the day represents a strategy for improving the performance of an inpatient phlebotomy service.

Interpretation and utility of drug of abuse immunoassays: lessons from laboratory drug testing surveys

CONTEXT

To assist with patient diagnosis and management, physicians from pain services, drug treatment programs, and the emergency department frequently request that urine be tested for drugs of abuse. However, urine immunoassays for drugs of abuse have limitations.

OBJECTIVE

To use data from the College of American Pathologists Proficiency Testing Surveys to determine and summarize the characteristics, performance, and limitations of urine immunoassays for drugs of abuse.

DESIGN

Six years of urine drug testing proficiency surveys were reviewed.

RESULTS

Lysergic acid diethylamide and methaqualone are infrequently prescribed or abused and, therefore, testing may be unnecessary. However, implementation of more specific testing for methylenedioxymethamphetamine and oxycodone may be warranted. Each drug of abuse immunoassay exhibits a different cross-reactivity profile. Depending on the cross-reactivity profile, patients with clinically insignificant concentrations of drugs may have false-positive results, and patients with clinically significant concentrations of drugs may have false-negative results.

CONCLUSIONS

Laboratory directors should be aware of the characteristics of their laboratories' assays and should communicate these characteristics to physicians so that qualitative results can be interpreted more accurately. Furthermore, manufacturer's claims should be interpreted with caution and should be verified in each organization's patient population, if possible.

Earlier detection of myocardial injury in a preliminary evaluation using a new troponin I assay with improved sensitivity

Cardiac troponins are important biochemical markers for defining the presence of myocardial injury. However, limitations in troponin testing exist, including the relatively late increase in troponin after onset of ischemia. We therefore evaluated a more sensitive troponin assay for detection of myocardial injury in "early presenters." Discarded serial specimens were obtained from 103 patients who had a negative cardiac troponin I (cTnI) result followed by a positive cTnI result. Results were obtained using our current cTnI method and a new more sensitive assay, TnI-Ultra (Siemens Medical Solutions, Diagnostics Division, Tarrytown, NY). Medical records were reviewed to determine the clinical diagnosis. Precision studies yielded a 10% coefficient of variation at the diagnostic cut points for cTnI (0.10 ng/mL [0.10 microg/L]) and TnI-Ultra (0.04 ng/mL [0.04 microg/L]). TnI-Ultra was positive before cTnI in 66 (64.1%) of 103 cases. We conclude that the more sensitive assay, TnI-Ultra, has better analytic performance and has the potential to detect myocardial injury earlier than the current cTnI assay.

Selecting Automation for the Clinical Chemistry Laboratory

Context.—Laboratory automation proposes to improve the quality and efficiency of laboratory operations, and may provide a solution to the quality demands and staff shortages faced by today's clinical laboratories. Several vendors offer automation systems in the United States, with both subtle and obvious differences. Arriving at a decision to automate, and the ensuing evaluation of available products, can be time-consuming and challenging. Although considerable discussion concerning the decision to automate has been published, relatively little attention has been paid to the process of evaluating and selecting automation systems.

Objective.—To outline a process for evaluating and selecting automation systems as a reference for laboratories contemplating laboratory automation.

Design.—Our Clinical Chemistry Laboratory staff recently evaluated all major laboratory automation systems in the United States, with their respective chemistry and immunochemistry analyzers. Our experience is described and organized according to the selection process, the important considerations in clinical chemistry automation, decisions and implementation, and we give conclusions pertaining to this experience.

Results.—Including the formation of a committee, workflow analysis, submitting a request for proposal, site visits, and making a final decision, the process of selecting chemistry automation took approximately 14 months. We outline important considerations in automation design, preanalytical processing, analyzer selection, postanalytical storage, and data management.

Conclusions.—Selecting clinical chemistry laboratory automation is a complex, time-consuming process. Laboratories considering laboratory automation may benefit from the concise overview and narrative and tabular suggestions provided.

Interpreting Tricyclic Antidepressant Measurements in Urine in an Emergency Department Setting: Comparison of Two Qualitative Point-of-Care Urine Tricyclic Antidepressant Drug Immunoassays with Quantitative Serum Chromatographic Analysis

Patients taking tricyclic antidepressants (TCA) can experience toxicity or severe side effects. As a rapid and less technically demanding alternative to quantitative serum analysis, most laboratories offer qualitative immunoassays to assist in the evaluation of a suspected TCA overdose. However, the relationship between quantitative serum and qualitative urine levels of TCA-related compounds and their metabolites has not been comprehensively studied. Serum high-performance liquid chromatography results were compared to the qualitative urine results using the Syva Rapid Test and the Biosite Triage. Serum concentrations of amitriptyline, desipramine, doxepin, imipramine, and nortriptyline ranging from subtherapeutic to toxic triggered a positive response on both urine immunoassay devices. On the other hand, neither immunoassay uniformly detected clomipramine, even at serum levels greater than the therapeutic range. False positives due to cyclobenzaprine were more common with the Biosite assay. For virtually all positive urine TCA findings, it was not possible to determine whether the positive results corresponded to subtherapeutic, therapeutic, supratherapeutic, or toxic serum concentrations. Because urine immunoassays are the only option for many laboratories analyzing specimens for TCAs (especially in an emergency setting), clinicians must understand the limitations and interpret results in conjunction with clinical findings and/or quantitation of serum levels.

Utilization of arterial blood gas measurements in a large tertiary care hospital

We describe the patterns of utilization of arterial blood gas (ABG) tests in a large tertiary care hospital. To our knowledge, no hospital-wide analysis of ABG test utilization has been published. We analyzed 491 ABG tests performed during 24 two-hour intervals, representative of different staff shifts throughout the 7-day week. The clinician ordering each ABG test was asked to fill out a utilization survey. The most common reasons for requesting an ABG test were changes in ventilator settings (27.6%), respiratory events (26.4%), and routine (25.7%). Of the results, approximately 79% were expected, and a change in patient management (eg, a change in ventilator settings) occurred in 42% of cases. Many ABG tests were ordered as part of a clinical routine or to monitor parameters that can be assessed clinically or through less invasive testing. Implementation of practice guidelines may prove useful in controlling test utilization and in decreasing costs.