Modern recompression therapy includes several therapeutic options employed differentially based on the capabilities of the treating facility; the severity and delay of the presenting case; and the effectiveness of, complications experienced during, recompression therapy. They are:

• 2.8 ata oxygen tables (USN Treatment Tables [USN TT] 5 and 6 or Royal Navy [RN] Tables 61 and 62)

• 6 ata mixed gas / air tables (e.g., USN TT 4 [or RN 54 or 55] and USN TT6A)

In spite of the relatively wide range of pressure-gas-time choices and the paucity of research and outcome comparisons to other recompression procedures, USN TT 6 remains the most popular first-line treatment in use today. Available evidence suggests that this table is adequate in the majority of cases if treatment is initiated immediately 10. Unfortunately there is often considerable delay in initiating treatment meaning that the secondary effects of the bubbles become more significant. Under these circumstances Kelleher has shown that initial treatment is curative in only 66% of the cases 36. Even so, none of the alternative proposed protocols, including saturation decompression, have clearly distinguished themselves as being superior to USN TT 6 128-130. There may however be certain conditions where Heliox or greater pressure are definitely indicated. These include blow-ups from saturation and commercial Heliox diving as well as immediate recompression treatment for DI following recreational Trimix dives. In this conditions, extreme bubble formation and differences in partition coefficients of helium and nitrogen in the tissues may favor the use of greater pressure and mixed gas 2.

The use of gas mixes, particularly Heliox, for the treatment of DI following compressed air diving, remains controversial. A practical approach to the various therapeutic choices is to commence with recompression on oxygen at 2.8 ata and only in the presence of deteriorating or severe refractory DI (and even then only if experience and available infrastructure permits this) to consider 4 ata and 6 ata mixed gas regimens.

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