illed ▁or ▁hypoth em ic ▁diver ▁can ▁restore ▁imp a ired ▁circul ation ▁to ▁the ▁extrem ities . ▁If ▁the ▁in ert ▁gas ▁load ▁is ▁low , ▁this ▁may ▁improve ▁the ▁rate ▁of ▁gas ▁elim ination , ▁but ▁larger ▁in ert ▁gas ▁loads ▁might ▁be ▁pushed ▁to ▁the ▁point ▁of ▁b ubble ▁formation ▁or ▁growth ▁due ▁to ▁temperature ▁effects ▁on ▁sol ub ility . ▁Which ▁of ▁these ▁effect ▁will ▁pre dom inate ▁is ▁un predict able ▁and ▁may ▁even ▁vary ▁in ▁the ▁same ▁diver ▁in ▁a ▁given ▁instance . ▁The ▁war ming ▁of ▁t issues ▁preced es ▁the ▁increase ▁in ▁blood ▁flow , ▁so ▁b ub bles ▁may ▁become ▁problem atic ▁before ▁circul ation ▁can ▁remove ▁the ▁gas . ▁This ▁risk ▁is ▁not ▁am enable ▁to ▁numerical ▁analysis ▁and ▁there ▁are ▁many ▁variables . ▁The ▁risk ▁is ▁likely ▁to ▁reduce ▁with ▁the ▁passage ▁of ▁time , ▁lower ▁gas ▁loading , ▁and ▁higher ▁initial ▁temper atures ▁of ▁the ▁extrem ities . ▁F lying ▁or ▁as cent ▁to ▁alt itude ▁soon ▁after ▁div ing : ▁This ▁is ▁known ▁to ▁increase ▁risk ▁as ▁it ▁is ▁in ▁effect ▁further ▁decom pression . ▁There ▁are ▁specific ▁recommend ations ▁to ▁manage ▁risk ▁in ▁such ▁cases . ▁In ▁most ▁cases ▁they ▁are ▁equivalent ▁to ▁a ▁long ▁decom pression ▁stop ▁on ▁air ▁at ▁sea ▁level ▁ambient ▁pressure ▁before ▁asc ending ▁to ▁a ▁higher ▁alt itude , ▁to ▁ensure ▁that ▁the ▁cont rolling ▁t issues ▁are ▁sufficiently ▁des atur ated . ▁Several ▁rules ▁of ▁thumb ▁have ▁been ▁recommended ▁over ▁the ▁years .