POCT for troponin for chest pain in the emergency department is associated with a reduction in patient journey times and is achieved without sacrificing assay reliability or increasing re-attendance
Paul RE Jarvis BSc(Hons) MBChB MRCP FCEM Dip Med Ed
Consultant in Emergency Medicine,
Calderdale and Huddersfield NHS Foundation Trust, UK;
Clinical Associate of the Lean Enterprise Academy
Lean is a manufacturing philosophy that has its origins in the Japanese automobile industry.(1) The fundamental principle of Lean is improving efficiency and throughput by removing those things that do not add value from the customer’s perspective.
What is meant by ‘value’?
Lean would define value in healthcare as the right care, provided on time and in full.(1) Essentially, value relates to the quality of care we provide. For a step in the healthcare process to add value, it must aim to improve the patient’s condition in some way, or add information that assists with making a diagnosis. Anything that does not do either of these is waste.
Value is not how cheaply we can provide care, as solely focusing on this can lead to a reduction in quality. Instead of chasing cost reductions the best way of saving money is to eliminate or reduce those things that do not add value.
Unlike most other industries, in healthcare, our customers (the patients) are also our product (the entity we provide a service on).(2) Consequently, it is very important for us to consider the care we deliver through the eyes of the patient. As clinicians, we must continually ask ourselves two questions:
- Is what I am currently doing adding value from the patient’s perspective?
- How do I remove those things that do not add value from a patient’s perspective?
Here, we show how these questions can be applied to a clinical setting.
Consider a patient presenting to the emergency department (ED) with chest pain, and who is suspected of having an acute coronary syndrome. Reaching the correct diagnosis in this patient group is crucial because under-diagnosis could lead to the patient with a myocardial infarction being discharged from the ED. Equally, over-diagnosis can lead to unnecessary admission and further investigations.
To make the correct diagnosis, the clinician needs the findings of their clinical assessment in conjunction with the results of blood troponin tests and electrocardiography. Negative investigations may lead to discharge from the ED, avoiding unnecessary admission, whereas early identification of a patient with an elevated troponin level means prompt referral to specialist care.
Adding value from the patient’s perspective
What would value look like from the perspective of a patient suspected of having an acute coronary syndrome? If I were the patient, I would want to be assessed by a clinician with sufficient seniority, skill, experience and authority to make the correct diagnostic decisions. I would like this to occur as early as possible, and for that clinician to have the results of any investigations available to them in as short a time as possible. Sadly, this is not always a reality.
A common form of waste in healthcare is the amount of time patients are made to wait. Waiting is endemic in healthcare and is dependent upon the availability of clinicians and the results of investigations. It seems culturally acceptable to make patients wait as part of their care. Timeliness of care is one of the main factors that contributes to patient satisfaction in the ED.(3)
Consequently, if making patients wait is endemic in our processes, and how long patients wait directly affects how satisfied they are with the care they receive, then this is a problem. Our services are designed to make patients unsatisfied with the care they receive. As clinicians, we should never stop looking for ways to reduce patient waiting times with the proviso that the pursuit of shorter waiting times does not compromise the standard of care that is delivered.
One area of preventable delay in the patient journey is the time that patients and clinicians have to wait for the results of blood tests. The traditional model of blood samples being sent to a central laboratory for analysis is associated with delays in the result being available to the clinician because of the time spent transporting samples to the laboratory, registration of the sample, batching, processing and authorisation of results. Currently, in my own department it takes between 60 and 90 minutes for a troponin result to become available. During this time, the patient’s progress through the care pathway stalls as they are made to wait for the result of their investigations.
Removing those things that do not add value
If we reduce the amount of time the patient waits for results, value from the patient’s perspective is increased because non-value adding time is reduced. Subsequently the patient’s experience is improved. Obviously, having to wait up to 90 minutes for the information that is necessary to make the correct clinical decision is unsatisfactory and does not fit in with the definition of value from the patient’s perspective.
The timeliness of the troponin result is also vitally important to the clinician, because it allows prompt initiation of the correct treatment. In addition, it would reduce the time clinicians have to wait for information necessary for making the decision about the most appropriate next stage in the patient care pathway. A more prompt diagnosis, initiation of treatment and referral to specialist care all add value from the patient’s perspective.
One way of reducing the length of time it takes for troponin results to be available is the introduction of point of care testing (POCT). POCT differs from laboratory testing because the test is performed at, or near, the patient’s bedside. This reduces the time taken for the result to be available because it removes the need for transportation, registration and authorisation of the blood sample in the laboratory.
Using a handheld POCT analyser at the patient’s bedside in the ED means the time from blood being drawn to a result being available is approximately 10 minutes4 rather than the 60–90 minutes for a laboratory assay. Providing the result is as reliable as a laboratory troponin result, it would suggest this is a step towards achieving the patient’s vision of value and facilitates quicker decision making for the clinician.
Impact and reliability of POCT troponin
Several studies(5–7) have confirmed that introducing POCT for troponin in the ED reduces the journey time of patients presenting with suspected acute coronary syndrome. The range of reductions in overall patient journey times in the ED demonstrated was between 24 and 42 minutes (mean, 34 minutes). Implementation of POCT for troponin in the ED was also associated with a reduction in the number of hospital admissions and shorter lengths of stay for patients who were admitted.(8)
Hart et al(5) demonstrated that implementation of POCT for troponin was associated with a reduction in errors, such as results being placed in the wrong patient’s notes, blood tubes being labelled incorrectly, and the wrong tests being requested.
Bock et al(9) and Loten et al(10) demonstrated that POCT for troponin can be used reliably in EDs for the correct diagnosis of patients with suspected acute coronary syndrome. Laboratory evaluations of POCT troponins are accurate and equivalent to laboratory-based diagnosis.(11) Implementation of POCT was shown to be associated with shorter patient journey times in the ED for patients with suspected acute coronary syndrome with no associated increase in six monthly readmission rates.(12)
Cost effectiveness of POCT troponin
The cost of POCT for troponin is approximately 2.75-times more than laboratory testing on a test-by-test basis.(13) Naturally this would seem a disincentive to implement this new technology into the ED. However, looking at individual unit costs does not take into account the impact that reducing patient journey times has on patient satisfaction or shortening time from arrival in the ED to obtaining a diagnosis and ED occupancy.
There are concerns around having easy access to rapid diagnostics may result in junior staff requesting unnecessary investigations. Asha et al(14) propose this can be guarded against by redesigning the ED processes, such that a senior clinical decision maker can decide the investigation profile after assessing the patient as early into the patient journey as possible. This would ensure the patient receives the correct and appropriate investigations early and would prevent over-investigation. In addition, it would take full advantage of the reduction in the time it takes for the result to become available that POCT delivers. The similarity between this model and that proposed earlier in this paper relating to the patient’s perspective of value should not be ignored.
A paradigm shift is required to improve patient satisfaction in the ED. We should not accept the status quo. Patient experiences should be used to drive service improvements in our organisations. By focusing on the things that add value from the patient’s perspective, we can remove waste from our care pathways. By listening to our patients and considering the journey through their eyes we can make huge in roads into improving patient satisfaction.
One way of challenging the status quo is to look for ways of reducing the amount of time we make patients wait. In the context of suspected acute coronary syndrome, introducing POCT for troponin into EDs is associated with a reduction in patient journey times when compared with troponin assays being performed in a remote laboratory. This reduction in journey time is achieved without sacrificing the reliability of the assay or an increase in re-attendance.
- Womack JP, Jones DT. Lean thinking: Banish waste and create wealth in your corporation. New edition. Simon & Schuster/Free Press;2003.
- Baker M, Taylor I, Mitchel A. Making hospitals work. Lean Enterprise Academy Ltd;2009.
- Welch SJ. Twenty years of patient satisfaction research applied to the ED: A qualitative review. Am J Med Qual 2010;25(1):64–72.
- Apple FS et al. Decreased patient charges following implementation of point-of-care cardiac troponin monitoring in acute coronary syndrome patients in a community hospital cardiology unit. Clinica Chimica Acta 2006;370:191–5.
- Hart KW, Lindsell CJ, Ryan RJ. A time-and-motion study of the processes required to obtain cardiac biomarker assays using central laboratory, near-patient testing, and bedside point-of-care testing. Point of Care 2012;11(2):61–8.
- Singer AJ et al. Point-of-care testing reduces length of stay in ED chest pain patients. Ann Emerg Med 2005;45:587–91.
- Koehler J et al. Effect of troponin I point-of-care testing on ED throughput measures and staff satisfaction. Adv Emerg Nurs J 2013;35(3):270–7.
- Goodacre S et al, on behalf of the RATPAC Research Team. The randomised assessment of treatment using panel assay of cardiac markers (RATPAC) trial: a randomised controlled trial of point-of-care cardiac markers in the ED. Heart 2011;97(3):190–6.
- Bock JL, Singer AJ, Thode HC. Comparison of ED patient classification by point-of-care and central laboratory methods for cardiac troponin I. Am J Clin Pathol 2008;1:132–5.
- Loten C et al. Validation of a point of care troponin assay in real life ED conditions. Emerg Med Australas 2009; 21(4):286–92.
- Collinson PO. The need for point of care testing: an evidence-based appraisal. Scand J Clin Lab Invest 1999;230:67–73.
- Rathore S et al. Is it safe to discharge patients from accident and emergency using a rapid point of care triple cardiac marker test to rule out acute coronary syndrome in low to intermediate risk patients presenting with chest pain? Eur J Intern Med 2008;19(7):537–40.
- Bingisser R et al. Cardiac troponin: a critical review of the case for point-of-care testing in the ED. Am J Emerg Med 2012;30(8):1639–49.
- Asha SE et al. Impact from point-of-care devices on ED patient processing times compared with central laboratory testing of blood samples: a randomised controlled trial and cost-effectiveness analysis. Emerg Med J 2013; Jun 7 [Epub ahead of print].