This week I attended the PeriopMan Anaemia conference, hosted at the Renaissance Hotel in Manchester City Centre. This was a half day conference focused, rather unsurprisingly, on the topic of anaemia and the impact that is has on perioperative care. For those of you that hadn’t heard of them, the Manchester Perioperative Medicine Society (PeriopMan), are a group based in Manchester with the established aim of bringing focus to collaborative working in perioperative care. Whilst they first started back in 2013, the society as it is now was launched back in 2016. They tend to have an annual conference in October and a further smaller conference at this time of year. To find out more information check out their website: https://www.periopman.co.uk/
The Challenge
Professor Andrew Klein opened the afternoon by asking the questions about why we are actually so interested in perioperative anaemia. The answer is not completely beyond doubt (we are still lacking the highest level of evidence), but there is significant observational evidence on the correlation between pre-operative anaemia and worse outcomes, including both morbidity and mortality. This seems to be correlated with the increased need for transfusion, for which the adverse effects are increasingly being recognised. In cases where it has been aggressively targeted, for example where blood management has been required by law (Italy, Western Australia), the impact on transfusion rate and mortality has been impressive. The confounding here is obvious (I’m sure that there were a number of other changes in surgical technique and perioperative care) but the pattern is pretty suggestive.
Is this actually a big problem though? Well the answer seems to be a resounding yes. There is a decent variation across specialties, but an average of 39.1% of patients undergoing major surgery will have anaemia. And the extent of anaemia doesn’t have to be huge to have an impact - a threshold of 130g/L seems to consistently be the point below which risk increases. This risk also appears to be a progressive - the more anaemic you are, the higher your perioperative risk. An interesting side note pointed out by Professor Klein here was the impact on women. He described how the WHO definition of anaemia in women was based on a number of population studies in the 1950s; populations which likely included a decent incidence of iron deficiency. The concern here is that a degree of pathology may have crept into the definition of ‘normal’. The problem is that women bleed in exactly the same way as men, and actually the on-average smaller circulating volume compared to men means that there is an increased impact from an equivalent blood loss. This is actually demonstrated in some studies with a demonstrably worse outcome in women. Using separate haemoglobin thresholds for women may therefore be physiologically unjustified and visibly harmful. Indeed, the most recent consensus guidance advises us to just use a threshold of 130g/L to define anaemia, regardless of gender. (https://onlinelibrary.wiley.com/doi/full/10.1111/anae.13773)
Is this actually a big problem though? Well the answer seems to be a resounding yes. There is a decent variation across specialties, but an average of 39.1% of patients undergoing major surgery will have anaemia. And the extent of anaemia doesn’t have to be huge to have an impact - a threshold of 130g/L seems to consistently be the point below which risk increases. This risk also appears to be a progressive - the more anaemic you are, the higher your perioperative risk. An interesting side note pointed out by Professor Klein here was the impact on women. He described how the WHO definition of anaemia in women was based on a number of population studies in the 1950s; populations which likely included a decent incidence of iron deficiency. The concern here is that a degree of pathology may have crept into the definition of ‘normal’. The problem is that women bleed in exactly the same way as men, and actually the on-average smaller circulating volume compared to men means that there is an increased impact from an equivalent blood loss. This is actually demonstrated in some studies with a demonstrably worse outcome in women. Using separate haemoglobin thresholds for women may therefore be physiologically unjustified and visibly harmful. Indeed, the most recent consensus guidance advises us to just use a threshold of 130g/L to define anaemia, regardless of gender. (https://onlinelibrary.wiley.com/doi/full/10.1111/anae.13773)
Interesting note from Prof Andre Klein: WHO anaemia definition for women based on population data that probably included iron deficiency anaemia i.e. the pathology integrated into what is 'normal', giving the lower threshold #periopanaemia
— Thomas Heaton (@tomheaton88) March 28, 2019
How is this best approached? The answer here seems to be as early as possible, and the challenges that are encountered often come from organisational aspects. The treatment is usually one that will take time to have effect. Iron deficiency is by far the most prevalent cause, mostly on its own but also in combination with other causes, such as anaemia of chronic disease. This needs a period of treatment before the benefit will be seen, ideally at least 2 weeks. This is frequently not the case in current NHS systems where patients may be rocking up at pre-op clinic a few days before their scheduled operation. The case is even more challenging with oral iron. This needs even longer to have an effect and is frequently beset by issues of poor tolerance or simple inadequate efficacy. Even worse, the inflammatory state (which will often accompany a number of surgical pathologies such as cancer) will often elevate hepcidin levels, further impairing enteral utilisation of iron. Oral iron is still recommended by NICE in cases when there is time, but there is a fairly high number of cases where a delay is not going to be suitable, for example cancer surgery. It is here that IV iron has become increasingly employed to optimise the chances of an adequate response in time.
Really important point by Prof Klein - Hepcidin levels notably increase after the surgical insult. Post-op oral iron is liekly to do nothing #periopanaemia
— Thomas Heaton (@tomheaton88) March 28, 2019
Implementing Change
There were then some excellent talks about the implementation of perioperative anaemia pathways at a local level, describing how some of these challenges were being met. Dr Iain Gall first outlined his work looking at the anaemia burden in abdominal surgery in Manchester. It was particularly interesting to hear about the relationship between anaemia and CPET; a relationship that I suppose could be expected given the history of EPO (ab)use in some elite athletes. He demonstrated the quite stark impact of anaemia on transfusion practice, with transfusion rates a whole 10 times higher in the anaemic cohort. It’s one thing to be able to read about these differences in journals, but as Iain noted it was quite a different thing to present these results to your own colleagues as a driver for change. A great topic for local QI work.
Dr Rachel Brown followed with another great summary of driving quality improvement work forward in Manchester through their pre-operative anaemia pathway. Through the conception and development of a pilot scheme they were able to show some similarly impressive results in reducing transfusion requirements locally. She outlined some of the challenges faced in doing this, many of which relate to the fairly discordant nature of perioperative pathways currently. As already noted, the timeframe for intervention is tight, and historically the pre-operative assessment has been more about just gathering information rather than doing anything about it. As a haematologist by background, she provided some useful insights into the service and some of the pathways that may be less familiar to us anaesthetists/intensivists which are often needed for day admission for IV iron therapy. Again a theme here was one of resources. Even the development of a service such as this, with pretty well demonstrated benefits, was a challenge. On the short term horizon the increasingly effective therapies for other conditions, she highlighted an upcoming weekly treatment for myeloma as an example, would likely take up more capacity and lead to further competition for resources.
The final speaker was Dr Caroline Evans. She is a consultant anaesthetist from Cardiff who described a similar story in improving pre-operative anaemia care locally to her. The same challenges were being identified in terms of a high incidence of pre-operative anaemia and the subsequent transfusion demands - her own practice being in cardiothoracic anaesthesia. The implementation of a pathway to tackle this faced a number of problems that had been touched on already. Getting agreement for a policy that involves a wide range of professionals and specialties is no small task, never mind finding capacity to deliver an intervention that needs space, staff and time. These are recurring themes. An example of this being tackled is the attempt to ensure that only a single admission is needed for IV iron therapy, which has triggered a switch to the use of Monofer. Just having to get people to come back for a second infusion, with all the associated demands on services, never mind the impact on patient lives, had quite a detrimental impact on actually achieving the goal of iron repletion.
Dr Rachel Brown followed with another great summary of driving quality improvement work forward in Manchester through their pre-operative anaemia pathway. Through the conception and development of a pilot scheme they were able to show some similarly impressive results in reducing transfusion requirements locally. She outlined some of the challenges faced in doing this, many of which relate to the fairly discordant nature of perioperative pathways currently. As already noted, the timeframe for intervention is tight, and historically the pre-operative assessment has been more about just gathering information rather than doing anything about it. As a haematologist by background, she provided some useful insights into the service and some of the pathways that may be less familiar to us anaesthetists/intensivists which are often needed for day admission for IV iron therapy. Again a theme here was one of resources. Even the development of a service such as this, with pretty well demonstrated benefits, was a challenge. On the short term horizon the increasingly effective therapies for other conditions, she highlighted an upcoming weekly treatment for myeloma as an example, would likely take up more capacity and lead to further competition for resources.
The final speaker was Dr Caroline Evans. She is a consultant anaesthetist from Cardiff who described a similar story in improving pre-operative anaemia care locally to her. The same challenges were being identified in terms of a high incidence of pre-operative anaemia and the subsequent transfusion demands - her own practice being in cardiothoracic anaesthesia. The implementation of a pathway to tackle this faced a number of problems that had been touched on already. Getting agreement for a policy that involves a wide range of professionals and specialties is no small task, never mind finding capacity to deliver an intervention that needs space, staff and time. These are recurring themes. An example of this being tackled is the attempt to ensure that only a single admission is needed for IV iron therapy, which has triggered a switch to the use of Monofer. Just having to get people to come back for a second infusion, with all the associated demands on services, never mind the impact on patient lives, had quite a detrimental impact on actually achieving the goal of iron repletion.
Final Thoughts
So I had better wrap things up now. I think there are a few key themes that are really worth taking away from the meeting. Perhaps the first one is that this anaemia is a really common problem in patients undergoing moderate and major surgery. This seems to be a clear risk factor for worse outcomes in many ways, for both the patient and the hospital. This is such a good target for continuing the transition from preoperative assessment to preoperative optimisation that the widespread challenges to tackling it seem to be worth taking on. The projects discussed here had already demonstrated reduced transfusion rates, and even length of stay, as well the financial savings described by Professor Klein that would appear to naturally accompany such benefits (iron is not an expensive intervention, blood is). This last point is often a deal breaker in a resource stretched NHS, bumping it up the list of effective but pragmatic interventions that are vying for attention. At the end of her talk, Dr Evans drew the parallel with the idea of marginal gains in leading sports teams. Normalising, or even improving your patient’s haemoglobin levels isn’t particularly flashy or exciting, but the benefits are there. I’m not even entirely sure that the gains are that marginal.
As always please leave any comments and ideas below. I have linked a few useful resources below if you want to read a bit more about the topic. I have to say a big thank you to PeriopMan and all the speakers for a really interesting and excellently hosted afternoon. I’m completing my application for the October event straight away.
Hopefully see you there.
Tom
As always please leave any comments and ideas below. I have linked a few useful resources below if you want to read a bit more about the topic. I have to say a big thank you to PeriopMan and all the speakers for a really interesting and excellently hosted afternoon. I’m completing my application for the October event straight away.
Hopefully see you there.
Tom
Further Reading
- Anaesthesia. Special issue: Patient optimisation before surgery. 2019. 74(1). https://onlinelibrary.wiley.com/toc/13652044/2019/74/S1
- Munoz, M. et al. International consensus statement on the perioperative management of anaemia and iron deficiency. 2017. 72(2):233-247. https://onlinelibrary.wiley.com/doi/full/10.1111/anae.13773
- NICE. Anaemia - iron deficiency. 2018. https://cks.nice.org.uk/anaemia-iron-deficiency#!topicSummary
- Munoz, M. et al. ‘Fit to fly’: overcoming barriers to preoperative haemoglobin optimization in surgical patients. BJA. 2015. 115(1):15-24. https://academic.oup.com/bja/article/115/1/15/238472
- Froessler, B. et al. The Important Role for Intravenous Iron in Perioperative Patient Blood Management in Major Abdominal Surgery: A Randomized Controlled Trial. Annals of Surgery. 2016. 264(1):41-46. https://journals.lww.com/annalsofsurgery/Fulltext/2016/07000/The_Important_Role_for_Intravenous_Iron_in.9.aspx
- Australian Red Cross Blood Service. https://transfusion.com.au/
- Heaton, T. Iron deficiency anaemia. The Gasman Handbook. 2018. http://www.thegasmanhandbook.co.uk/iron-deficiency-anaemia.html
Image courtesy of LuAnn Hunt from unsplash.com
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