Everyday practice: tried, trusted and tested? Here’s why we need evidence

Health professionals carry out many established interventions as part of caring for their patients. Established practices may be so familiar, and so widely accepted, that they aren’t questioned. Sarah Chapman consider this here in an area of everyday nursing practice, pressure ulcer management, but hopes this will be read in the context of other areas of healthcare too.

Page last updated: 26 June 2022 and last checked 4 April 2023

Say hello to PressureGone!

imaginary gadget
What would you need to know before using a new intervention with your patient?

Imagine that I’m writing here to tell you about an amazing new device (let’s call it PressureGone) for treating pressure ulcers or, even better, one that its developers say will eliminate the risk of getting pressure ulcers in the first place. It uses cutting edge technology and you’ve never seen anything like it. Pause a moment before you grab the lovely shiny PressureGone with one hand and bin your patient’s sheepskin with the other. What do you want to know about it?

New intervention: what do you need to know?

You’ll certainly need to know how PressureGone should be used in order to do what it promises. How often, for example? If it’s something that’s applied intermittently, the impact on resources (staff time and maybe materials) will be much greater if it needs hourly use, as opposed to once daily. Having the PressureGone treatment frequently could be a considerable nuisance to your patients too, disrupting sleep, increasing pain and so on. Thinking of which, you’ll want know if it has any potential harms associated with it and what patients feel about it. You’ll need to know the methods or techniques required, to ensure it benefits your patients and does no harm. You might also be asking questions like ‘does it work better with some types of patients than others?’ I hope you’re asking ‘what’s the evidence?’ What’s more, how do you know that PressureGone is better than what you do now unless you have robust evidence about the effectiveness and potential harms of both?

Old intervention: same questions?

Now think about something you actually use as part of pressure ulcer management. Some of this is a very long way from using cutting edge technology, such as encouraging patients to change position, or repositioning those who can’t do it by themselves. Repositioning is a recognized element of international best practice for managing pressure ulcers and first mentioned as a method of prevention in the mid-nineteenth century. Do you need to know the same things about it as you do about PressureGone, asking the same sorts of questions?

You might be quick to point out that in terms of the physiology of pressure ulcer development and healing, repositioning makes sense. Also, unlike PressureGone, repositioning has been used for a long time and it seems to work; in research-speak, it has ‘face validity’. Tick, tick.

Now, how often should it be done? Your workplace has a really good track record for pressure ulcer prevention and healing, so your two-hourly repositioning regime seems to be working. So does hospital X and care home Y, where they turn people three- and four-hourly respectively. So actually how often do people need to be repositioned? How can we know? It matters, not just for your pressure ulcer incidence and healing rates but for the impact on patients, staff and resources.

The guidelines will tell us, won’t they?

Nurse repositioning elderly woman
What’s the evidence for what you do?

Good idea, let’s check the guidelines. Well this can be problematic. The authors of a Cochrane review on repositioning said that lack of agreement between guidelines was one of the reasons why this review was necessary. They noted that, in the USA, the  guidelines from the Agency for Health Care Policy and Research (now archived) advocated two-hourly repositioning (AHCPR 1992), while the European Pressure Ulcer Advisory Panel & National Pressure Ulcer Advisory Panel and the National Institute for Clinical Excellence advocated repositioning as required by the individual patient (EPUAP/NPUAP 2009; NICE 2005). The two-hourly recommendation was based on small, non-randomized studies carried out more than twenty years ago and their usefulness further compromised by the improved standard of hospital mattresses and support surfaces. And people still get pressure ulcers. How can we prevent that?

These guidelines have now been updated but things haven’t really moved forward. The latest guidance from NICE leaves things fairly loose; adults at risk should change their position ‘frequently and at least every 6 hours’, and we should ‘consider more frequent than every 4 hours for neonates’.  There’s no agreement on the optimal frequency of repositioning because we lack evidence to inform practice, as the NICE guideline highlights. If this was PressureGone and there were no instructions about how often to use it, I reckon you’d be demanding to know.

Moving on to how to move…

Next, should you go for the 30 degree tilt or the 90 degree lateral rotation? How about going for the tilt, or maybe the turn, and using a pressure redistribution mattress? If you use repositioning plus the mattress, does that affect how often you should do it? But then we’ve seen that the optimal frequency isn’t something you can be sure about anyway…

What’s the latest evidence?

A Cochrane review on Repositioning for treating pressure ulcers (January 2015) which hoped to address these uncertainties, found no eligible randomized studies. Another, Repositioning for pressure injury prevention in adults was updated in June 2020 but still has only low or very low certainty evidence, and the review authors say “there remains a lack of robust evaluations of repositioning frequency and positioning for PI [pressure injury] prevention and uncertainty about their effectiveness.”

Evidence matters

Preventing pressure ulcers, and promoting healing when they do occur, is bread-and-butter patient care. You’re working with a knowledge of physiology and the effects of pressure on tissue and some basic techniques and equipment which have a sound theoretical rationale. But that’s not enough.

Evidence matters; knowing what is most likely to work, what to use and how to use it and for whom, and how to avoid harm. Regrettably, there is a very poor evidence-base for most aspects of pressure area management, in terms of its assessment through reliable research. For funders, policy makers and health professionals, it’s important to know what the best available evidence says and to advocate for its use, and for interventions to be tested in rigorous trials, so that today’s best practice can become tomorrow’s better, evidence-based practice.

References (pdf).

Sarah Chapman has nothing to disclose.









Everyday practice: tried, trusted and tested? Here’s why we need evidence by Sarah Chapman

is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International

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