Industry News


High-Sensitivity Troponin: Quality and Productivity in Near-Patient Testing

 BY DAVID STEIN, PhD, CONNIE MARDIS, MEd, AND AMY SARLI

David Stein.copy Connie.copy Amy.Sarli.copy
David Stein, PhD, is
CEO,
Point of Care
business unit,
Siemens
Healthcare
Diagnostics,
Tarrytown, NY
Connie Mardis, MEd,
is director, marketing
communication
programs, Siemens
Healthcare Diagnostics,
Tarrytown, NY

 

Amy Sarli is global
marketing manager-
POC Cardiac, Siemens Healthcare Diagnostics, Tarrytown, NY

  

 

 

 
 
 
 
 
 
 
 

               

               Laboratories with near-patient testing responsibilities continue to focus on productivity, quality, and cost reduction. This article examines streamlining workflow and improving turnaround time (TAT) in near-patient testing settings while producing high-quality results with a strong correlation to the central lab. High-quality results are especially important in cardiac biomarkers used to help diagnose acute coronary syndrome (ACS) or acute myocardial infarction (AMI) in patients presenting to the emergency department (ED).
A laboratory’s strategy to reduce the time from “order to result” of high-sensitivity troponin, defined as an imprecision level (%CV) of ≤10% at the 99th percentile of normal by the joint ESC/ACC committee, is discussed. Cardiac biomarker time to result is one key to earning Chest Pain Center (CPC) Accreditation. Hospitals seek CPC Accreditation from the Society of Cardiovascular Patient Care (SCPC) to be recognized as one of the best heart hospitals in the world. The mission of the SCPC is to reduce heart attack deaths.
The SCPC methodology for improvement includes a self assessment and an external peer assessment. Data is accumulated, the level of performance is evaluated, and improvements are suggested to build in quality, improve customer satisfaction, and cut costs.1

Cost Pressures
A 2009 Clinical Laboratory News survey of 524 US hospital labs, academic medical centers, and reference labs found that more than 50% of respondents were under a high level of pressure to cut costs in their labs (see Figure 1).2
 At education events across the country each year, straw polls conducted by the authors of this paper find that the budget crisis has not abated for laboratories, even though the country is slowly recovering from the recession.

     Figure 1: 2009 CLN Survey of Labs impacted by Recession
Pressure to_Cut_Cost_copy
 
Concurrently, the demand for laboratory services is expected to rise, driven in part by demographic changes of an aging Baby Boomer populace anticipated to require more health care services. Point-of-care (POC) testing is increasing, particularly for those diagnostic tests that provide actionable information to health care providers quickly, typically within 30 minutes or less. The decreased turnaround time that POC testing provides can have a direct effect on improving provider or patient workflow and convenience, or on improving patient outcomes.3
The value of the information provided to clinicians from laboratory tests is clearly recognized. While laboratory costs make up only 2.3% of a hospital’s budget, laboratory services affect 60% to 70% of all critical clinical decisions, such as whether to admit, discharge, and/or initiate therapy.4 The route to hospital admission of critically ill patients is often through the busy doors of a hospital ED. Cardiac testing for ED patients is a case in point.

The Golden Hour and Emergency Room Workload
Cardiovascular diseases (CVDs) are the number one cause of death in the United States and globally.5,6 In 2011, chest pain and related symptoms were the third leading principal reason for ED visits in the United States, affecting more than seven million of more than 136 million patients treated.7
Not every patient having a cardiac event suffers from chest pain, which complicates diagnosis. While chest pain or discomfort is the most commonly known heart attack symptom in men and women, many patients instead present with atypical symptoms that can mimic the flu or a pinched nerve, such as nausea, fatigue, lightheadedness or numbness in the arm, jaw, or back.8
Women are somewhat more likely to experience atypical symptoms, particularly shortness of breath, nausea/vomiting, and back or jaw pain. Other atypical heart attack symptoms in women can include breaking out in a cold sweat, dizziness, lightheadness or fainting, pain in the lower chest or upper abdomen, and extreme fatigue. Women often brush off these symptoms as the flu, stress, or feeling under the weather.9
Heart disease strikes more women than men in the United States, and is the number one killer of women. Yet only one in five American women believe that heart disease is her greatest health threat.10 Whether it is disbelief, lack of awareness, or misdiagnosis, dismissing the symptoms of a heart attack can delay critical, life-saving actions including coming to an ED, and may put lives in jeopardy.9  
Patients presenting with atypical symptoms may also have diagnoses delayed in part due to ED caseloads. The annual number of ED visits has increased by 23% in just 10 years11, and in that time 381 EDs ceased operating as 535 United States hospitals closed.12
Heart attacks, or cardiac myocardial infarctions (MI), occur when the flow of blood to the heart is blocked by a buildup of plaque in coronary arteries. All ED cases of suspected MI can be life-threatening because if a coronary artery is blocked, the heart muscle loses critical blood flow and begins to die after 30 to 60 minutes. During this ‘golden hour’ of heart attack, it is often said that time is muscle. Every minute of delay in treatment after that hour means more heart muscle will die.13
        To optimize patient outcomes for this most threatening disease, early detection, risk stratification, and placing patients on the correct clinical treatment pathway is critical. The development of more sensitive and specific serological biomarkers and precise imaging techniques allows detection of ever smaller amounts of myocardial necrosis. High-sensitivity troponin assays are improving the diagnostic accuracy and rapid detection of myocardial infarction (MI).14
        Cardiac troponins are regulatory proteins within the muscular layer of the heart wall. They are released into the circulation when damage to cardiac muscle cells has occurred. Cardiac troponins have high myocardial tissue specificity as well as high clinical sensitivity. Serum troponin is a very sensitive marker of myocardial injury and is necessary for establishing a diagnosis of MI.14             

Why High-Sensitivity Troponin*?
According to National Academy of Clinical Biochemistry (NACB) Guidelines, assays for cardiac biomarkers should strive for a total imprecision (%CV) of <10% at the 99th percentile reference limit of a normal population.15 Guidelines, or critical care pathways, are common in diagnosis and treatment. These strategies result in: 

1. rapid initiation of crucial therapy in patients with high risk acute coronary syndromes

2. risk stratification of clinically low risk patients into those requiring admission and those who can be safely discharged and managed as outpatients.1

The criteria of the universal definition of AMI is detection of a rise and/or fall of cardiac biomarker values, preferably cardiac troponin, with at least one value above the 99th percentile upper reference limit (URL) of the reference value distribution in the setting of a patient with clinical features of myocardial ischemia (see Figure 2).16

Fig 2_copy
 
Advances in immunoassay technologies have resulted in development of troponin assays with unprecedented analytic sensitivity and precision. A rise or fall in serial high-sensitivity troponin levels strongly supports an acutely evolving cardiac injury such as, most commonly, acute myocardial infarction.
The ability to provide earlier detection of MI may improve outcomes and patient satisfaction, because high-risk patients are triaged sooner in the emergency setting. That was the goal of Baptist Memorial Hospital-Desoto in Southaven, Miss (Baptist).

Journey to Chest Pain Center (CPC) Accreditation
Rick Tucker, MLS(ASCP); DLM(ASCP), director of Pathology Services at Baptist had worked hard to reduce TAT for all testing received from their ED. Baptist sought CPC Accreditation, and the TAT for cardiac troponin had to be reduced from the 70 minutes it had been taking for “order to report” results from the central lab.

Earning CPC Accreditation is an accomplishment that lets physicians, patients, and the community know that a hospital meets quality-of-care measures based on improving the process for the care of the acute coronary syndrome (ACS) patient. Nearly 800 hospitals have earned CPC Accreditation. 

The SCPC Assessment Tool is patient-centric, and is derived from peer-reviewed literature, professional society guidelines, and the body of clinical acumen of participating clinicians. The review criteria are a product of leading professional societies, including the American College of Cardiology, the American Heart Association, the American College of Cardiovascular Administrators, and the Emergency Nurses Association.

An operational model, the Assessment Tool starts from the onset of the patient’s symptoms, and includes engagement of Emergency Dispatch Services, Emergency Medical Services, Emergency Department and Catheterization Lab, observation unit, cardiac rehab, and discharge from the facility. The Assessment Tool lists eight Key Elements1 critical to the care of the patient with symptoms of ACS. Sections pertaining to lab testing are highlighted below:

SCPC Assessment Tool Excerpt – 8 Key Elements for CCP Accreditation1

|1| Community Education and Early Heart Attack Care (EHAC)
|2| Emergency Integration with Emergency Medical Services (EMS)
This element calls for the facility to ensure lab instruments in the Central Lab and ED are synchronized to ED time measurements.
|3| Emergency Assessment of Patients with Symptoms of Acute Coronary Syndrome (ACS)  – Timely Diagnosis and Treatment of ACS
This element discusses that cardiac biomarker TAT must be timely, defined, and “order to result” in 30 minutes tracked. Baseline cardiac markers, serial single Troponin, and serial Multi-Marker or Delta Marker Strategy are covered.

|4| Assessment of Patients with Low Risk for ACS and No Assignable Cause for their Symptoms.

Patients who meet triage criteria due to symptoms of ACS but have normal or non-specific ECGs remain at some risk for ACS, even if their index cardiac biomarker results are within the normal reference range.

An estimated 20% of the money awarded in malpractice suits against ED physicians is related to the misdiagnosis and mistreatment of ACS.

This population of patients may be managed in a number of ways that may include short stay admission, outpatient observation, imaging protocols, serial cardiac biomarker testing, or other methods supported by the literature and consistently applied across the patient population.

|5| Process Improvement

|6| Personnel, Competencies, Training

|7| Organizational Structure and Commitment

|8| Functional Facility Design 

  

“It’s been a journey. First we replaced the main chemistry analyzers to reduce TAT. But actually, the time to result was not so much a limitation of the chemistry analyzer, but more a function of all the wait steps along the way. Even after implementing stat spin centrifuges, we hit a plateau of 55 minutes from order to result,“ Tucker says.17 Baptist evaluated four instruments that could produce troponin results in the near-patient ED setting. “We chose a high-sensitivity troponin* that was the only one that met ESC/ACC guidelines for recommended CVs, the Stratus CS. It closely resembled results from our lab, was the most LEAN with fewest steps to results, and was the most economical.”
A high-sensitivity troponin* assay available in the United States for the near-patient setting, Troponin I on the Stratus® CS Acute Care™ Diagnostic System, meets ESC/ACC guidelines (see Figure 3) for use as an aid in the diagnosis of AMI, and as an aid in the risk stratification of patients with ACS with respect to their relative risk of mortality. The Stratus CS system accepts heparinized whole blood samples, and requires no preanalytics such as centrifugation or manual dilutions.
Fig 3_copy 
 
 
 
 
 
 
 
 
 
 
 
  
 
 With “order to result” time as low as 24 minutes, Baptist received CPC Accreditation in December 2011. ER visits have increased by more than 20%, and an estimated 23,400 high-sensitivity troponin* samples were run in the ED in 2012.
Regarding ease of use, interpretation, and impact of high-sensitivity troponin* available in the ED, Tucker says “Phlebotomists draw the specimen and can run the instrument. They enter a patient identifier, insert cartridge, and press “go.” Our protocol specific to troponin is initial high-sensitivity troponin*, and repeat at 90 minutes. If both are negative, the patient is either moved to observation or discharged, depending on their clinical presentation. If moved to observation, the troponin values done after the first 90 minutes are run in the central lab. Positive results are run through our critical value process and the result is reviewed by an MT or MLT before being reported. If negative, the result is sent straight to the physician and patient record electronically by autoverification with the laboratory information system (LIS). High-sensitivity troponin* in the ED helps get the patients moved to the next stage of treatment. With the tremendous volume that we’re seeing in the ED, it’s important to speed the patients on their way to diagnosis and treatment, which frees up bed space for new patients arriving, and helps with patient satisfaction.”

Cost savings
                 Rapidly identifying patients with a noncardiac diagnosis could save thousands of dollars on unnecessary tests and treatment. There is growing recognition of the need for cardiac troponin results to be available in 60 minutes or less after patient arrival in hospital outpatient departments.18
             A 2010 study by Premier Healthcare Alliance examined which innovations drive improved outcomes and cost savings. Among other improvements, the study compared clinical and financial outcomes of hospital EDs using the Stratus CS system for rapid identification of ACS patients with those from EDs not using the system. The study findings suggest that patients for whom Stratus CS system with the high-sensitivity Troponin* I assay is used during inpatient treatment may experience shorter lengths of stay, lower mortality, and lower total cost versus the non-Stratus CS system users (see Figure 4).      
   ED admissions in three hospitals from the Premier database that would allow pre- and post-analysis were studied: Citizens Medical Center, Victoria, Tex; Methodist Park Nicollet, St Louis Park, Minn; and Baptist Hospital, Miami. The target study population was adult inpatients aged 18 and older discharged between January 2003 and May 2011 with a principal diagnosis code of MI or ACS. The Premier database includes approximately 5.5 million inpatient discharges per year since 2000.18
Fig 4_copy
Future Trends
We believe there will be continued emphasis on technology that is easy to use, with devices that run a broad menu of critical tests such as high-sensitivity troponin*, D-dimer, and NT-proBNP from a single, whole-blood sample near the patient with central-lab quality and seamless connectivity.
The biggest improvements are expected to happen outside the instrument, in what we call the “POC Ecosystem.” As regulatory requirements are strengthened, operator management, compliance reporting, and training will continue to be key areas of focus for innovation and customer-centered improvement. As use of this testing continues to expand, more users will have to operate an increasing number of devices. They will need to be trained accordingly to maintain an adequate level of proficiency.3
 Innovation in near-patient testing will be driven by laboratory requests to manage increasing critical testing volumes, help improve clinical outcomes, and increase patient satisfaction. 
 
[*Defined as an imprecision level (%CV) of ≤10% at the 99th percentile of normal by the joint ESC/ACC committee.]
 
References:
1. Society of Cardiovascular Patient Care Accreditationaccessed 12/5/12

2. Malone, B. The Recession Squeeze, Labs coping with tough times. Clinical Laboratory News, 35(2):20-21. Feb 2009.

3. Sparrow, N. Cultivating a POC Ecosystem. IVD Technology, Aug 8, 2012. 

4. Laboratory Medicine: A National Status Report, The Lewin Group, May 2008. National Vital Statistics Report, US Department of Health and Human Services, CDC.61:6, p6. Oct 10, 2012. 

5. National Vital Statistics Report, US Department of Health and Human Services, CDC.61:6, p6. Oct 10, 2012.

6. Cardiovascular diseases Fact Sheet #317, World Health Organization, Sept 2012.  

7. National Hospital Ambulatory Medical Care Survey: 2009 Emergency Department Summary Tables, pg 12. 

8. Heart Attack Symptoms in Women, American Heart Association, Sept 5, 2012.

9. American Heart Association, Go Red for Women, accessed 1/4/13. 

10. Heart Disease and Stroke Statistics – 2012 Update: A report from the American Heart Association. Circulation. 2012;125:e2-e220; originally published online Dec 15, 2011.

11. Niska R, Bhuiya F, Xu J: National Hospital Ambulatory Medical Care Survey: 2007 Emergency Department Summary. National Health Statistics Reports; no 26. Hyattsville, MD: National Center For Health Statistics, 2010.

12. AHA Hospital Statistics, Health Forum, Chicago, IL. 2008.

13. Canto, J, et al. Association of Age and Sex with Myocardial Infarction Symptom Presentation and in-hospital Mortality. JAMA, 307(8):813-822, Feb 2012. 

14. Daubert M, Jeremias A. The utility of troponin measurement to detect myocardial infarction: review of the current findings. Vasc Health Risk Manag. 2010; 6: 691–699. 

15. Laboratory Medicine Practice Guidelines: Biomarkers of Acute Coronary Syndromes and Heart Failure. Edited by R. Christenson. NACB. Copyright© 2007 by the American Association for Clinical Chemistry Inc.

16. Thygesen, K, Alpert JS, Jaffe, AS et al. White HD. Joint ESC/ACCF/AHA/WHF Expert Consensus Document : Third Universal Definition of Myocardial Infarction. Circulation, Aug 24, 2012

17. Rick Tucker interviewed by C. Mardis. Dec 5, 2012.

18. Moretz C, Robinson SB, Johnson B. Validation of high-sensitivity troponin I method in acute coronary syndrome patients [abstract]. Society of Chest Pain Centers (SCPC), Orlando, FL, May 2012.