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Jason Rodgers posted the following on 16/11. >But perhaps you need someone who was actually diving *MiGplan* rather than >This happened three weeks ago; > >The diver conducted a normal dive on Heliair to 76 msw. The dive profile >was governed by MiGplan set to full conservative (20%). >On surfacing the diver complained of pain in the shoulder joints. He was >placed on 100% O2 and DES was contacted (Divers Emergency Service). >They contacted the local hospital and a discussion took place, the details of >which I don't know. The diver was then transported to a MILITARY chamber >who were set up to treat heliox DCI. >He was initially taken to 60 fsw on 100% O2, then 100 fsw on 50% He 50% O2. >He improved slightly. He was then switched to 20% He 80% O2 (PPO2 3.2 bar) >and he improved greatly. After being held at that depth for some time he >was raised to 60 fsw and then given a table 6 with full extensions. >All 'air' breaks were taken on Heliox.> > >He was still suffering some symptoms at the end of the table 6 treatment. >Apparently a Heliox saturation treatment was considered but was rejected. >Follow up HBO treatments where given to try to clear up residual symptoms. > >Ohh one other thing, while discussing air/air diving, Jody mentioned; >"In practice, I don't like to decompress that long, so instead I come up >at 1500PSI or 30MINS of deco." >I hope you realise that your software is being used for *much* bigger dives >that that every weekend. 120 minutes of NTX and O2 enhanced deco is not >that uncommon over here. 60 minutes of air/O2 deco after an air dive is >a dead stock, standard, normal dive. We do it every weekend. If you dove >like that here people would look at you funny. Jason, jason, jason........... Some facts about the dive & diver in question: 1. Diver had reported shoulder pain was existing PRIOR to the dive due to possible strain (though this can always manifest itself as a pre-existing injury once the diver has a DCI symptom....DCI denial?). 2. Diver used a reasonable He heliar mixture (14% O2) and ONLY ONE DECO GAS, a Nitrox 50/50. As can be well explained by simple physiology, it is much more effective to get off the He as soon as possible & maintain a high PO2 as often as possible (CNS dosage taken into consideration of course). Any table using a modified Bulhmann will only be as effective as the use of the tools provided. For example, O2 is x2.5 as effective at eliminating N2 as air, yet when tables are run in comparison you do not find the stops divided by that ratio. There is a known conservatism built into any algorithm to make it as "real" as possible, but only true emperical tests can effect a table for each person. Decrease your O2 content & remain on the He for longer and any conservative factor within the table is lessened. 3. As for using MigPlan on the dive.....the diver was using a pirated copy.....pirate beware!!! 4. As for the safety of MigPlan....I have used this table extensively over the last 12 months on many gas dives to the same depth/duration. Dive plan has off He as soon as possible & use 2 nitrox gases for deco (32 & 80). Safety factor is only b (5%) as MigPlan has built in safety in taking ascent to first stop as part of bt. Maybe I'm lucky for the average beer swilling middle 30's diver, but so far so good (touch wood). The case you mentioned may have more to do with other factors than the table. As for the diving of others...each to their own. Regards Richard T ----------------------------- Diver: do Not Bend -----------------------------
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