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The accident slope – an analogy for avoiding errors

Early in my training as a glider pilot my instructor showed me an excellent but simple analogy for ensuring my safe performance as a pilot. I have always remembered this lesson, which he called the “accident slope”, and have tried to apply it to my method of practising medicine, as well as the other “dangerous” activities for which I have an affinity.

“Accidents and mistakes are seldom the result of one single error” he said, “but more commonly the combination of a multitude of mishaps — each of which on its own may seem minor, but when superimposed, spin with increasing speed towards tragedy.”

“Think of anything you do as if you were a mountaineer moving along a mountain ridge from your point of origin to your destination. The top of the ridge is perfectly flat, but falls away gradually to your side, becoming vertical. The covering is snow and ice, safe to walk on when level, but slippery on the slope.”

“The perfectly safe route would be along the top of the mountain, where there is no gradient and very little chance of slipping. This represents the safe and well-prepared route. Anything that affects you negatively moves you away from this flat route to where the gradient is steeper. Some of those things may be your own condition or unpreparedness, or may be external factors such as the weather.”

“It is much harder walking along a gradient, particularly when it is slippery. The more things that are wrong before you start, the further down the slope you are, and the more critical your position, and the harder it is to get back onto the level route. You may find yourself so far down the slope that an unexpected factor beyond your control pushes you to a level where slipping and falling becomes inevitable.”

“It all depends on where you start. Start too far down the slope, and you are an accident just waiting to happen.”

I know from experience, both in flying and in medicine, that his analogy is correct. I think of all the times I have worked when I am exhausted, demoralised, angry or frustrated; when I have had to fight with insurance companies who will not authorise the operation for my patient already in the hospital; when my particular choice of drugs is not available, or the prosthesis I need has not been ordered. I know at those times I am at higher risk of making a mistake.

And this time, in terms of the analogy, I have not just my route along the slippery slope to worry about, but also the health and welfare of my patient, the person I carry on my back.

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