Introduction
Over half a million people in the UK are currently waiting for trauma and orthopaedic procedures (including upper and lower limb surgery), which is over 42,900 more than in 2019: almost 35,000 have been on the waiting list longer than 12 months.
A proportion of these procedures will require the use of a tourniquet, so operating departments need a reliable, effective limb exsanguination procedure prior to the tourniquet cuff being inflated.
This is critical, not only for the safety of the patient, but also to ensure best use of theatre time: if exsanguination is not effective at the first attempt, and second attempt / alternative method has to be used, valuable time will be lost, which can be ill afforded as hospitals strive to reduce surgical waiting lists.
Current methods
There are four main methods of limb exsanguination used by practitioners today:
Elevation
Hand-over-hand squeeze
Esmarch bandage
The Rhys Davies Exsanguinator (RDE) - a pressurised exsanguination device
The first three of these can be arduous and time consuming - and methods 2 and 3 are unsuitable over broken bones
The pressurised exsanguination device method
Since it's introduction in 1985, the Rhys Davies Exsanguinator¹ (RDE) has become the most popular exsanguination device available in the UK health service. Essentially, it is an inflated elastic cylinder, rolled on and off a limb to provide effective, time-saving limb exsanguination.
The sequence is:
Apply the tourniquet to the limb - but don't inflate it
Roll the RDE on to the limb, forcing blood back into the rest of the body
Inflate the tourniquet to prevent arterial supply / venous return to the exsanguinated limb
Roll the RDE off the limb
However, while the device is essentially robust, care needs to be taken to ensure it continues to work effectively for the duration of its maximum potential service life.
There are a number of concerns that are sometimes raised about the RDE which are addressed as follows:
"It's a potential source of cross-contamination"
No more so than the reusable tourniquet cuff that will often accompany it: while, the RDE can't be sent for sterilisation or autoclaved, it CAN be effectively cleaned with the same detergents and disinfectants as the reusable cuff.
The best way to clean the RDE is to roll the device along a surface, whilst wiping, allowing for every part of its construction to be cleaned and disinfected quickly and conveniently. Drying and proper storage of the device is then crucial to maintain its effectiveness.
Any breakdown or cracking on the surface material of the RDE, which could be seen as a potential trap for bacteria or other pathogens, is a sign that the device has:
not been adequately dried following cleaning and disinfection
not been kept in the storage bag it is supplied with (the bag protects against ozone and UV light which degrade the material)
exceeded its 12 month life expectancy
"It's not exsanguinating effectively"
The RDE is pressurised, and just like a bicycle tyre, it's performance will be affected if its required pressure - 60mmHg - is not maintained. Another way of checking it's functioning properly is to measure its circumference, which is 47cms (18.5") when new. The circumference of the RDE will gradually expand with use and when it reaches 66cms (26"), it need to be replaced.
"They burst during use"
There is no record of an RDE (which has been monitored and maintained according to usage instructions) ever bursting during its 12 month life expectancy.
"It's not Latex free"
True: the RDE is manufactured from a dry natural rubbed compound derived from the same source as natural rubber latex, but its latex allergen level is vanishingly small.
Below 5μ/g is considered very low or no 'activity' - and dry natural rubber compound has a level of 1μ/g, so the RDE is not really considered to be a cause of latex protein allergy.
This is borne out by the fact that there have been no known adverse incident reports around latex allergy relating to the RDE in over 35 years of use.
However, it is important to note that natural rubber degrades over time, which is why the RDE is given a 12 month life expectancy. Exceeding this time period will have a detrimental effect on its performance.
So, the following checklist will ensure that the RDE works to its maximum effectiveness:
Dry thoroughly following cleaning and disinfection
Keep in storage bag (and box if possible) to protect from ozone and UV light when not in use
Routinely check the pressure (should be 60mmHg) and circumference: should be greater than 47cm (18.5") but less than 66cm (26")
Replace every 12 months - regardless of level of use or care and maintenance
Summary
On average, 420 Rhys Davies Exsanguinators are supplied annually in the UK. If used (according to a conservative estimate) 4 times per day, 4 days per week, for 48 weeks of the year - the RDE exsanguinates 322,560 limbs per annum.
Given its unblemished record over 35 years, during which literally millions of limbs will have been exsanguinated, the verdict on the RDE must surely be: safe, effective and proven.
To download the article - click here: A Device That Takes Care of Exsanguination Article
References
Annals of the Royal College of Sugeons of England (1985) vol.67 - The Rhys-Davies exsanguinator