An NT pro BNP test is the first step in the diagnostic pathway for suspected heart failure and is outlined in the NICE Chronic Heart Failure and NICE Acute Heart Failure guidelines to triage which patients then require an echocardiogram to confirm a diagnosis of heart failure.
During a World Café discussion at the Kent, Surrey and Sussex (KSS) Heart Failure Collaborative event in October 2018 we identified widespread concerns about unnecessary repeat testing, testing NT pro BNP when a diagnosis of heart failure is already known, patients having an echo despite a 'normal' NT pro BNP result, and patients not having an echo despite an elevated NT pro BNP result.
This QI project aimed to reduce inappropriate NT pro BNP testing in this pathway and thus focus on appropriate use of NT pro BNP in the diagnostic pathway for heart failure.
Aims and objectives
The aim of the project was to reduce inappropriate use of NT pro BNP testing (for example repeat testing, and testing NT pro BNP when an echo confirmed diagnosis of heart failure was already known) and importantly thus focus on the appropriate use of NT pro BNP testing as part of the diagnostic pathway for patients with heart failure.
This is an important part of the implementation of the NICE chronic heart failure guideline in the community and the NICE acute heart failure guideline in hospitals.
Reasons for implementing your project
At our round table World café discussions at the KSS Collaborative meeting in 2018, we discussed some of the key challenges arising from the updated NICE guidance. One of the areas for discussion was how NT pro BNP is used currently within both primary care and secondary care patient pathways.
There were 100 people included in the World café discussions; clinicians working across community and hospital sites in Kent, Surrey and Sussex, along with managers, commissioners and audit staff. They reported variation in access to NT pro BNP across the network, and consistent concerns raised about patients having repeat testing, echo’s not being requested when an NT pro BNP is raised, some clinicians thinking NT pro BNP is diagnostic of heart failure, and concerns about overloading the echo system if NT pro BNP use was embedded further in the hospital setting.
We also had evidence of lack of compliance with NICE guidance regarding NT pro BNP use from a local audit performed by one of our cardiology registrars in July 2018. 300 patients were included in the audit (a month of consecutive patients having an NT pro BNP requested in the community or in hospital). Just over 50% of the patients who had an NT pro BNP requested were compliant with NICE guidance for use as a rule out biomarker for heart failure. Over 60% did not go on to have a specialist assessment / echocardiography despite a raised NT pro BNP. Despite the high negative predictive value approximately 10% of patients with a normal NT pro BNP still had a specialist referral and echo requested with none of these patients resulting in a diagnosis of heart failure.
This project is important for:
- Patients – to ensure they receive the test only when they need it, and when they do receive it that the result is acted upon appropriately so that they get a diagnosis made and treatment started.
- Hospital staff and GP’s – that they use this test in the correct cohort of patients, and then follow through on the result to support a patient diagnosis.
- Commissioners – to reduce costs of inappropriate testing, and inappropriate echo, and improve the diagnostic pathway for patients with suspected HF to improve treatment locally and reduce unscheduled care for patients as they wait for a diagnosis.
How did you implement the project
The project used Quality Improvement (QI) methodology. As the scope of the project was large we decided to focus on secondary care use as that is my clinical area. A project plan outlined the key stages of work – this was important so that we did not rush to finding solutions before scoping the range of contributing factors.
I spent time talking to clinicians – both nurses and doctors – which helped to understand their needs and their knowledge gaps. They identified barriers such as not having information to hand, such as an echo result, when making clinical decisions, leading to an NT pro BNP test being requested and an echo subsequently ordered despite the test already having been done. To help overcome this barrier we have ensured access to echo results on all the computer points that are accessed. They also cited lack of awareness regarding the use of NT pro BNP, recognising it as an important test. Issues they raised such as other reasons for NT pro BNP to be raised, not to do serial NT pro BNP testing and to be used in suspected heart failure only were built into the education sessions.
We developed a collaborative recommendation for NT pro BNP testing which outlined the NICE guidance, but also what the guidance means in a very practical way for staff. There were also examples in this recommendation showing where practice had deviated and the impact that this has on patient care. We then developed a summary poster that could be used locally in education sessions and a slide pack to support education. The slide pack included some real world data for their particular clinical area to outline the problem, an overview of NT pro BNP and how it fits into the diagnostic pathway for heart failure, a discussion about factors that can lower or raise NT pro BNP levels, and the local heart failure pathway in line with the summary poster. Education has been delivered to ED teams and medical teams.
The education sessions also raised other issues– for example placing the summary poster on our clinical guideline site for all to access, discussions regarding age-related cut offs and valve disease, reconfirming referral pathways into specialist HF care, and using order comms to stop repeat testing within a specified time frame which is currently being progressed.
It was also important to consider how we were going to measure the impact of our interventions, so data collection was embedded from the start, and I receive monthly data from Biochemistry on all patients in the Trust who have had NT pro BNP testing. In terms of data analysis, we have focused on one hospital site – in ED and RAMU – as these areas are high users and also are involved in the diagnosis of suspected heart failure. We have audited this data on a monthly basis, looking for compliance to NICE guidance and thus the collaborative recommendation.
We used estimated costs of an NT pro BNP test (£18.90) and an inpatient echo (£45.00) in order to quantify unnecessary costs within the pathway that could lead to cost savings.
The data was audited monthly for patients having an NT pro BNP test in ED and RAMU at one hospital site. Firstly, we looked at the number of NT pro BNP requests in each area. We then looked at result and whether they then had an echo appropriately or inappropriately (for example, had they had a previous echo confirmed diagnosis of HF? Was their NT pro BNP normal thus an echo not needed? Did they have an echo if NT pro BNP was raised?).
We also looked at whether they had a subsequent NT pro BNP blood test in hospital which would have been unnecessary. This data was then presented as deviations from the pathway.
Our audit identified 191 NT pro BNP tests from Apr to Aug 2019, with 87 out of 191 (46%) not following the appropriate pathway. In 5 months, a saving of £1323 could have been made by stopping unnecessary echo’s where NT pro BNP test results were normal and stopping repeat NT pro BNP testing in hospital when a heart failure diagnosis was already known. This financial impact does not include the hidden costs such as a delay to diagnosis due to a patient not receiving an echo despite a raised NT pro BNP or a patient receiving an unnecessary echo putting pressure on echo capacity and delaying appropriate echo requests. Also, a patient may continue to experience symptoms due to their heart failure not being diagnosed and treated leading to unnecessary GP appointments.
Key learning points
This project is still in progress. It is early days in terms of data reflecting key changes in practice, however the discussions with staff have been really helpful and have raised awareness about the appropriate use of NT pro BNP in the diagnostic pathway and have embedded this more into practice. Talking to a wide range of people has been one of the most important parts of this QI project. Data collection has also been vital - to understand the problem better, to demonstrate the problem to others, and to measure progress.
In addition by continually reviewing the data we continue to learn and understanding the problem and the focus of education may change as a result as we move forward. Concerns have been raised about this work increasing the demand on echo. What we have seen is that we are currently performing echo on patients unnecessarily, and other patients are not receiving timely echo. We want the right patients to get the right test at the right time and this QI project is working on achieving this.