Late onset of decompression illness (DCI)

IMCA has received a safety notice which provides a good reminder on the subject of decompression illness (DCI).

A company has reported that, following an air dive, a diver developed a pain in his arm more than seven hours after decompression. Due to the length of time between the dive and the complaint appearing, it was assumed not to be diving-related and painkiller medicine was administered.

On worsening, two hours later, the diver was recompressed, but his condition did not markedly improve. It is believed that the period of non-recompression allowed the gas bubble(s) in his tissues to expand and cause internal lesions before dissipating. Thus the later therapeutic treatments, designed to dissolve the offending ‘bubbles’, were unsuccessful, as they could not provide relief for existing physical lesions.

The company has reminded its personnel that whenever a diver reports complaints which appear consistent with type I and/or type II symptoms, even up to 48 hours following an air or nitrox dive, the divers must be recompressed immediately, in accordance with company DCI treatment procedures. This should take place immediately – before or in parallel with contacting the diving doctor. If the case is DCI, correct action will have been taken. If it is not a DCI, therapeutic recompression will not make things worse.