Effective Pain Assessment: An Introduction

Effective Pain Assessment: An Introduction

Dr Dominic Aldington, Consultant in Pain Management

Pain, at one level anyway, needs little introduction. It is almost a universal experience and for most of us pain is a simple concept in which it is thought to act as an indication of damage to the body. Unfortunately, this is not entirely correct as in reality pain is a highly complex condition and may not indicate damage.

One of the problems we are faced with is that in our (English) language we really only have one word for pain. Thus, someone who says they have pain may get a transient degree of sympathy but then everyone has had pain so what could be so bad about it? However, the pain of a dislocated finger is completely different to the constant pain after shingles, which is present every day even though there are negligible signs of damage to the skin.

So, “what is pain?” would be a fair place in which to start an introduction on pain. The International Association for the Study of Pain currently gives the definition:

“Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage”

Now the first few words are easy enough to understand but then the concept of emotions comes in and this is something that is often translated as “weakness”. A clear example of the importance of the emotional component of pain can be seen when one considers stubbing your toe. If this is done while enjoying a cool swim on a glorious beach on a hot day on holiday we would expect the experience of the pain to be different to a similar insult on an early winter’s morning when the heating does not work, the toast is burnt, the milk is off and the dog has just died.

The concept of potential tissue damage is again rather a strange one and is typically demonstrated with the apocryphal tale of the builder walking across a building site when he feels a tug at the foot. He looks down and sees the pointed end of a 6-inch nail poking up through his boot. He screams with pain and cannot be consoled until heavily sedated in hospital. His boot is gingerly removed and the nail is found to have passed between big and second toe without causing much tissue damage. However, throughout this experience the builder’s pain was real.

One approach is to consider pain as being made up of two fundamental components – the physical and the emotional- and every pain has both of these but in varying proportions. It is important to be clear pain has to have an emotional component otherwise it would not be “unpleasant”.

When you catch your thumb in a door you shake it and look at it. If it does not bleed too much but still wiggles and the pain goes quickly, then that is mostly physical. However, the longer a pain lasts the more the emotional component becomes part of the problem.

The emotional component is made up of three aspects. There is anxiety and worry and typically we worry about two things. We worry about the “meaning” of the pain, why is it there, what is causing it, what is going on. Then we worry about the future and how the pain will affect us and our lives and our work and relationships.

Pain also makes us unhappy, although not necessarily depressed. This typically occurs in four ways. It affects us directly to make us miserable. It commands our attention, both consciously and subconsciously so we are listening for the pain thus hearing it louder and more often. Pain isolates us socially, and finally pain interrupts our sleep and if we do not sleep we do not cope.

The final aspect of the emotional component is the frustration that accompanies it. We become frustrated that it does not go away, that promised cures do not work, and that life gets worse.

Thus, the physical component can be viewed as the transmission of the message up to the brain and the emotional component can be viewed as the unpleasantness experienced. Of course the degree of disability and the behavioural changes are subsequent phenomena.

March 2019, M-C-UK-02-19-0001