Volume 9b - History of Anaesthesia Society

He thereEore advocated very gentle surgery in conjlmction xith simple
local infiltration with procaine to block off the impdses coming from
the part on which he was operating, and he combined this with generql
anaesthesia with nitro~ oxide to elimimt? the nociceptive effect of
fear. He called this technique moci-association.
The prxedure in
aWcminal cases was layer by layer infiltration - skin,
s1'9f2ne0us
fat, rnilscle, peritoneum, and the mzsentery of the t3rgt orgms.
Patients operatd on under anoci-association recovered more rapidly and
had less ~stoprative shock than those ho had had surgery under deep
ether. The latter did W-11 enough during the opration under the
symp~thetico~tic stimulus of etherisation ht, in the a5sence of
fluid replacenent, became shocked in thr? long recovery p2rid before
autonomic control of Cqe perip~eral vascular system ;.ms restsred; in
contrast, tine ptients who had had their suirqery under anoci-association
recovered their vascular tone mfiidly and camparatively quickly
compensated for their hypovolaemia. Crile did not see it this w3y,
however; he believed that nitrous oxide had a protective effect on the
brain, whereas ether did not. He was rather unfair in contrasting
'nitro~ls oxide1 and 'ether', as he often did in his papers; in fact, the
nitrous oxide was often e riched with a little e,ther, especially for the
closure of the a ~ r n n . ~ ~ ~
What Crile had act~mlly done was to prcduce a form of what is now called
'%lanced anaesthesia'. If anoci-association is considered in relation
to Gray's now familiar triad of an< 3thesi.a (unconsciousness, reflex
suppression and muscular relsxation) it can be seen that, in Cri.le9s
anoci-association technique, reflex su.npression and relaxation are
largely taken care of by local anaesthesia, enabling ~mmnsciousness to
be maintained by very light anaesthesia.
John Lucky of the myo Clinic actually originated the term 'tnlanced
anaesthesia' in 1936 but his technique of 'a moderate amount of
preliminary hypnotic, a morlerate amount of local anaesthetic, a derate
amount of nitrow oxide or ethylene and a sufficient anount of ether to
obtain the desired result1 apparently owas much to Crilels ideas;=of
course, if you ask the present day examiqation candidate 'what is meant
by balanced anaesthesia ?', you \rill be referrad to tne nitro:ls oxide,
oxygen, muacle relay, technique, which Gr2y originally called
'selective anaesthesia .
Crile and his assxiates undertook extensive animal work using
trawtised dogs. They came to tile conclusion that they could
demonstrate actual histoloqical changes in the brains of t e a imls
which they believed to have been caused by nociceptive stinuli l 3 0 1 Bit,
as rmon pointed out in thc 19201s, the hyperchrornatic and chrmlytic
changes which they observed were identical with t%ose of extreme
cellular hypxia due to c?oillary stasis which is the primary lesion in
shoc!c, whatever the callse .'