Note: if you missed the part1 - especially with some definition - you can still read Scuba Diving Accident Part1.

4. Descriptive Protocol. Rather than imposing this somewhat artificial classification on the decompression disorders, a better understanding of the natural syndromes is likely to result if a descriptive system is used. To simplify what could otherwise end up as a bewildering collection of terms, the symptoms and signs of decompression illness will be discussed using evolution and manifestation terms.

4.1 Evolution.

The evolution term is used to describe the development of the condition PRIOR TO RECOMPRESSION. These terms are best used to describe decompression illness as it evolves. Because it is frequently a highly dynamic condition, the term used may change from one observation to the next, e.g. a condition will probably present initially as being 'progressive' as the patient becomes increasingly aware that something is wrong. However, the situation frequently stabilizes so that it may then be described as 'static'. The patient may then undergo a substantial improvement, occasionally to complete resolution of the symptoms, and at that stage be described as 'spontaneously improving'. Occasionally, the symptoms may then return or new symptoms appear in which case the condition would be described as 'relapsing'.

4.1.1 Progressive.

A condition may be described as progressive if the number or severity of symptoms or signs is increasing. Examples would include an increasing severity of limb pain or the involvement of additional joints or a neurological presentation in which the loss of motor or sensory function is becoming more profound or where the extent of any loss of function is increasing, such as the cephalic extension of a deficit with a predominantly spinal distribution. The development of a new manifestation such as a neurological symptom or sign in addition to limb pain also represents progression of the condition. Terms such as 'rapidly' or 'slowly' may be used to enhance the description of this evolution where this is appropriate. 'Rapidly' and 'slowly' would refer to the progression of symptoms over a period of minutes or hours respectively.

4.1.2 Static.

This is self explanatory. Neither the severity nor number of manifestations is changing substantially.

4.1.3 Spontaneously Improving.

It is common for a number of presentations of decompression illness to improve, albeit transiently in certain instances, without recompression. Substantial improvement must occur for this term to be applied. As with other evolution terms, 'improving' should only be used to describe events prior to recompression.

4.1.4 Relapsing.

Occasionally, cases which have improved spontaneously undergo a secondary deterioration. This is particularly true of some neurological manifestations. This term is used to describe such cases. When a condition gets worse in the absence of any spontaneous improvement it should be described as 'progressive'. 'Relapsing' should be reserved for cases which have, at some stage in their evolution, undergone substantial, spontaneous improvement.

Note: you can directly read the next part by following the link Scuba Diving Accident Part3 then Scuba Diving Accident Part4.