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Skip to 0 minutes and 20 seconds What is risk assessment and why is it important? So, every patient that comes in for surgery– in fact, every patient that is even contemplating an operation– should have an individualised risk assessment done. There are a number of different factors that can affect patient outcomes. Patient risk factors, themselves– their capabilities, their age, and, importantly, the type of surgery they’re having, and the acuity of it– will all be major players in whether or not the patient has a good or a bad outcome. And there are lots of other risks associated with surgery, related to the structures and processes within hospitals. But on a patient level, an individualised risk assessment will help us plan the patient’s perioperative pathway.

Skip to 1 minute and 3 seconds Help the patient to make the right decision for them about whether they want to proceed with surgery or not, and how to consider other options, as well. And, therefore, hopefully inform them better about what is likely to be ahead of them. And help them achieve the best possible outcomes for them.

Skip to 1 minute and 28 seconds What are the common risk assessment tools used in practice and what do they tell us? So, in general we can assess patients risk using measures of functional capacity. We can use biomarkers of health, or we can use any number of risk assessment tools, scores, or models. So, the functional capacity is commonly assessed using exercise testing. Biomarkers might, for example, include things like brain natriuretic peptide, which is produced by cardiac muscle. But what I’m going to focus on, really, is risk assessment tools, which we can use to calculate risk based on patient risk factors. So, for example, the surgical outcome risk tool is a very straightforward risk assessment tool that was developed by Surgical Outcomes Research Centre, here at UCLH.

Skip to 2 minutes and 14 seconds In conjunction with NCEPOD, it’s got six variables related to the patient’s general health, measured using their ASA score. The type of surgery that they’re having, whether or not they’ve got cancer, and their age– and you put all of those variables together into a calculator, of which you can find online or in an app– and it gives you a predicted risk of death within 30 days of your surgery. There are a number of other tools that can do that, such as, for example, the P-POSSUM tool, which has been very widely validated. So, assessed in lots and lots of different populations, and is a very good, accurate measure, as well, in certain populations.

Skip to 2 minutes and 51 seconds And then there are a number of tools that we can use for particular populations, such as, for example, the Nottingham Hip Fracture Score in patients who are having surgery for hip fracture. And then the Lee Revised Cardiac Risk Index, if we want to try and predict the risk of cardiac complications after surgery. So, there are lots and lots of different measures out there. Different studies will say that different ones are better or worse than others. I think the key thing, really, is just to use something. Use something that you’re familiar with.

Skip to 3 minutes and 18 seconds Use something, ideally, that is similar to tools that are being used by others in your department, so that you can discuss easily with your colleagues, surgeons, anaesthetists, nursing staff, and the patient, importantly, what you think the likelihood is of a particular outcome after surgery.

Skip to 3 minutes and 41 seconds What is the evidence base to support these tools? So, that’s a really good question, because risk assessment tools have been widely studied, but there are very, very few studies of the impact of using them on patient outcomes. So, for example, there are loads– hundreds and hundreds of studies which will test whether or not the P-POSSUM tool, or any one of the other widely used tools, is accurate in a particular population of patients. And that accuracy can be measured using discrimination, which is basically a measure of how well one would line up 100 patients in a row, in terms of their ascending risk. And, or calibration– So it’s how likely it is that a tool will accurately predict a particular outcome.

Skip to 4 minutes and 27 seconds So, almost like the observed expected ratio. Now, the difficulty with risk prediction tools is that we can use them in this way, but they haven’t really been studied very effectively for whether or not the decision making that we make after using these risk assessment tools, improves patient outcomes. And I think that’s an area of research that we really need to focus on in the future. But, in summary, there’s quite a lot of evidence out there that if you do a risk assessment, then it does make you think a little bit differently about how you manage the patient.

Skip to 5 minutes and 1 second So, for example, there’s data from the National Emergency Laparotomy Audit, which showed that patients of a similar risk, who did or didn’t have risk assessment prior to surgery, were more likely if they did have risk assessments, go to critical care after their surgery– which is where they belonged. So, just the action of doing the risk assessment– we think– impacts on clinicians’ thinking, and therefore, makes them more likely to send patients to intensive care after emergency laparotomy surgery.

Skip to 5 minutes and 35 seconds How do you explain unexpected results? Yes. Sometimes patients surprise us. The really good thing is when patients who we predict are going to be really high risk, do really well, and they sail through their surgery. And occasionally, sadly, the opposite can happen, and patients who we predict to have a good outcome– or have a high likelihood of good outcome– don’t do so well. And I think there’s a couple of reasons for that. The biggest reason is that risk assessment is a one-off process at the moment. So we predict the risk of the particular event, usually before an operation.

Skip to 6 minutes and 9 seconds But then what happens is we change the way– well, hopefully– change the way we approach looking after a patient, based on that risk assessment. So we might decide to send them to ITU. We might moderate the type of surgery that we do. We might be absolutely sure that we’ve got several consultant surgeons and several consultant anaesthetists in to look after the highest risk patient. And then if that patient does well, then that’s obviously a success of the way that they were looked after, rather than a failure of the risk assessment tool. So sometimes, that’s the reason that patients surprise us. Because we’ve done our best to modify their likely postoperative course, and that’s a treatment success.

Skip to 6 minutes and 46 seconds The flip side of that, of course, is that sometimes patients don’t do so well. And I think when we repeatedly, particularly, see patients who we hoped would do OK, not do so OK, it’s important for us to look at the way that we deliver care.

Skip to 7 minutes and 6 seconds How can we translate these outputs into meaningful outcomes for patients? It is one of the difficulties that we are only, generally, predicting the binary outcome of whether or not you’re alive or dead at 30 days, using these tools. That’s the endpoint that has been used most commonly in the trials, which have looked at all the studies, which have looked at the accuracy of these risk tools. And that, again, is a bit of a limitation in the literature. So what we really need to do as a community, is focus on assessing whether these tools accurately predict outcomes which matter to patients. So, for example, not just if they survive 30 days. But do they survive a bit longer than that?

Skip to 7 minutes and 41 seconds And do they survive with good quality of life? Particularly, for example, the patient that comes in for a hip replacement. That’s super important, because they don’t come in for a hip replacement because it’s a lifesaving operation. It’s a life enhancing operation. So, you want to know that your life is enhanced afterwards. And being able to predict the risk– or the likelihood of that– I think, is a really important thing for patients.

Skip to 8 minutes and 10 seconds What is the future of risk assessment? So, the most important area of work for risk prediction in the future, is going to be about how we improve the use of these tools for predicting outcomes, which matter to patients. How we improve the use of these tools, or the validity of these tools, for predicting longer term outcomes. And then, how we roll the use of these tools into collaborative, or shared decision-making with patients. So, if we explain to patients what we think their risk or likelihood is of a particular outcome, how can we help them then to come to a decision about whether or not to proceed down a particular treatment pathway is right for them?

Risk assessment tools

Professor Ramani Moonesinghe is the director of the National Institute of Academic Anaesthesia (NIAA) health services research centre as well as a Professor in Perioperative Medicine at University College London.

In this video Professor Moonesinghe discusses how use of risk assessment tools improves risk stratification in surgery. The risk assessment tools can be used to improve postoperative care planning for patients as well as being used as an aid to help patients make informed decisions about proceeding with surgery.

In the following article we will look at some of the risk assessment tools discussed here in more detail before revisiting the clinical vignettes laid out in the previous step.

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Perioperative Medicine in Action

UCL (University College London)