Perfusion service clinical outcomes

Clinical outcomes are measurable changes in health, function or quality of life that result from our care. Constant review of our clinical outcomes establishes standards against which to continuously improve all aspects of our practice.

The Perfusion service provides clinical perfusion services to the cardiothoracic service at GOSH. Perfusionists are responsible for setting up and running heart-lung machines, which are used to support patients during open heart surgery. They also set up and provide support for the extra corporeal membrane oxygenation (ECMO) machine and look after other machines including cell savers, blood gas machines, colloid osmotic pressure monitor, thromboelastograph, activated clotting time monitor and the intra-aortic balloon pump. Around 500 patients per year receive perfusion services.

A perfusionist performs heart lung bypass during open heart surgery. This process takes over the work of both the heart and the lungs by pumping oxygenated blood around the patient’s body. This allows the heart to be stopped so the surgeon may operate on it.

The perfusion team at GOSH are pro-active in monitoring the quality of their perfusion care over time, and using the data for improvement in performance.

The table below show five measures used by the perfusion department to assess the quality of perfusion delivered to our patients. This data is gathered for every case and is analysed annually for each perfusionist and for the department as a whole. For each quality indicator, the amount of time spent outside the ideal range is measured and the total minutes per case is recorded. This is then averaged over the caseload for the year.

There are many reasons for the data to be outside the ideal range, such as complexity of the surgery and the specific lesions being operated on. So, numbers outside the range must be considered in this context, but the broad aim is to stay within the optimal ranges as much as possible during surgery. However, they are useful benchmarking tools to allow us to ensure the quality of care delivered by the perfusion team remains high, and so improvements are made where possible.

The field of perfusion is constantly developing internationally as we learn more and adapt techniques. So, it can be difficult to meaningfully compare with other centres. However, from the UK surgical outcome data, shown here, we consider ourselves to be contributing to patient outcomes that are better than expected and of the highest quality when compared to other specialist paediatric centres.

The data shows that we improve over time, and demonstrates our commitment within the team to robust data collection and openness. Sharing individual perfusionist data within our team is an important way we learn and improve.

Figure 1 Perfusion service average minutes per case outside of range, 2012/13 to 2018/19

Ven Sat - Venous saturation. This is a measure of the oxygen content of the blood that has journeyed around the body. It is used to indicate adequate delivery of oxygen to the tissues of the body.

Art pO2 - Partial pressure of arterial oxygen. This is a measure of oxygen levels in the blood in the arteries of the body. Although it is vital for oxygen to be present in the arterial blood, too high a level over a prolonged period can lead to chemical changes in the body which can affect normal physiology.

B.E. - Base Excess. This is a measure of the chemical balance of the blood. If the B.E. is very negative, it can be an indication that the body is not receiving enough energy to keep up with metabolism. This can be a sign of not enough blood flow.

HCT - Haematocrit. This is the amount of red cells in the blood. This tells us how much oxygen the blood is able to carry. If the level is too low, then it can contribute to lower levels of oxygen being delivered to the tissues of the body.

C.I. - Cardiac Index. This is a measure of how much blood is being pumped relative to the size of the patient. People of different size and weight will have different blood flows, but their cardiac index will be (broadly) the same. It is often necessary to drop the blood flow for short periods during cardiac surgery. If the cardiac index is too low for too long, this can affect the delivery of oxygen to the tissues of the body.

This information was published in February 2020, and will be updated annually.