I received this on a email group I am on (addy at bottom) and thought
it very interesting info. Cobra venom; any volunteers??
This Doc is for real and puts together some great info in the mails he
sends out, I recommend his list to all.
Jeff


DIVEMED NEWSLETTER
November, 25, 2000

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The Complement System and Diving

Considerable research over the past 10 years has been directed toward
elucidation of the complement system and it's effect on the body in
association with bubbles. Reviewed nicely in 1997 by Andrea Zaferes in
the magazine 'Immersed', the complicated but important field of how
bubbles cause damage is slowly but clearly being brought to light.
http://www.immersed.com/Articles/hit.pdf

Long thought to be a simple process of blockage of vessels and
infarction, it has now been shown that there is a tripping of the
complement system and the immune system (T- and B- leucocytes) when
bubbles form from decompression. This immune response has a domino
effect on blood chemistry that leads to marked changes in the tissues
long after the bubbles are gone.

Work has also been done that shows the importance of early treatment.
The longer the period of waiting after a decompression incident, the
more blood chemistry changes occur and the greater the damage done,
emphasizing the importance of early recompression in the treatment of
decompression illness.

Very interesting studies have also shown that activation of the
complement system may acclimate you to the effects of a decompression
accident. This might be a 'using up' process of multiple shallow dives
with sub clinical bubbling causing complement activation and having
little or none present when a subsequent deeper dive is done. This
same process might be the explanation of the excessive fatigue that
many divers describe after diving - the fatigue actually being the
complement activation damage that is know to occur distant from local
bubble sites and the hemoconcentration that occurs.

Individuals who have greater sensitivity to complement activation may
be at greater risk for DCS manifestation and more severe DCS injury.
Conversely, those with chronically 'used up' complement may be a
lesser risk, as in the chronic asthmatic or the atopic patient.

Finally, there might be individual variation in the sensitivity to
DCS. Divers who are complement sensitive have a higher rate of DCS.
Sensitivity is definmd by tht level l C5a i ilease e lowininrlasmamal>incucupion w wr bubbbbt in v vho. HoHoser, L Lrgren n v assosodtes<>orkerersave a al foununhhat c coa venentfactotornds
r>b>Refeferces: : r>Shasasn KA, , rue GLGLiundgrgrgCE. R RLted A A cles s a>In v vio actctrtion n rhumananamplemem by n noogen n tbles.s.rr>Undndbea BiBibd Resess991 M Me18(3)3)17-65.5.;r>Berer5K, HjHjbe A, , rsen n d Brubube AO. . ,>Variriklity y rr timimif comomement t oivatitieinducuctby aiai ubblele br>ininbman a aJ ApApsPhysisir 199393 r;74(4(.1811-1-p
<><:Ward d McCuCu>ugh D D,raserero. J A Ak Physysb. 19898lar;6262l:116060M
r>)>Shasas. KA, , rue GLGLiundgrgrgCE, L LLe CJ,J, ggs D Du
D>Dung dede pressssi faililmo actctnte cocotementntabr>UnUnlsea H H
r>5d CA,A,rCullolor D, Y YcD, StStha D, , ser W Wg
C>Calemenen ctivavapn invnvaementnto decocovessioionicknenerofUnUnasea B Br>Eplememe.systetemesponon to dederpressss .
Brook WH, Secombe J, Seychell D.
Complement levels and exposure in the hypobaric chamber.
Aviat Space Environ Med. 1995 May;66(5):415-7.

Hjelde A, Bergh K, Brubakk AO, Iversen OJ.
Complement activation in divers after repeated air/heliox dives and
its possible relevance to DCS.
J Appl Physiol. 1995 Mar;78(3):1140-4.

Katuntsev VP, Kozlov LV, Shcherbakova MA, Ageev VP, Sizoi MN.
[Effect of decompression on the compliment system].
Aviakosm Ekolog Med. 1993 May-Jun;27(3):22-8. Russian.

Stevens DM, Gartner SL, Pearson RR, Flynn ET, Mink RB, Robinson DH,
Dutka AJ.
Complement activation during saturation diving.
Undersea Hyperb Med. 1993 Dec;20(4):279-88.

Zhang J, Fife CE, Currie MS, Moon RE, Piantadosi CA, Vann RD.
Venous gas emboli and complement activation after deep repetitive air
diving.
Undersea Biomed Res. 1991 Jul;18(4):293-302.

Huang KL, Lin YC.
Activation of complement and neutrophils increases vascular
permeability during air embolism.
Aviat Space Environ Med. 1997 Apr;68(4):300-5.



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Best regards for safe diving!
Ern Campbell, MD, FACS
Diving Medicine Online
http://www.gulftel.com/~scubadoc