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A completely new concept of anesthesia Has b e e n introduced with Yiadril, the first steroid to be successful in surgical anesthesia in man. The Pfizer group that dis­covered i t are : EL W . Rude! | left Κ S. Y- P ABU and G. D . Laubach

N e w Anesthetic Discovered Pfizer scientists d e v e l o p first successful steroid

product; opens new field of anesthesiology

NEW" YORK.—To the ever-g?-owing list of new drugs can now be 3L<ûaeû Via­dril, a new concept of anesthesia. 21-HydrGxypregoane - 3,20 - dione sodium succinate is claimed to be the first ster­oid used, successfully for surgical anes­thesia in man. Pfizer believes it opens an entirely new field of steroid research and offers hope of even broader medi­cal applications in the future.

History. Anesthetic properties of steroids were first noted in 1941 when H. Seîye. noted endocrinologist, re­ported that several steroidal hormones produced depressant effects i n rats and fish. Little attention was paid to Selves observation and no practical agent was derived from it.

Recently. G. D. Laubach of Pfizer disco\Tered that steroids, made hormon-ally inactive and water soluble, anes­thetized animals such as mice. dogs. and monkeys.

Laubach. working with S. Y. ΡΆη and Η. ΛΥ. Rudel. synthesized and evaluated more than 1O0 new water soluble steroids. One compound was found to have the desired anesthetic

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Yiadril

potency, therapeutic index, toxicity, a n d duration in animals.

Chemical Structure. Viadril is ob­tained b y a multiple step chemical syn­thesis. The steroid is made hormonally inactive by removal of the hormone functional groups. A water soluble functional group, such as an ionic ester, is then added.

Typical starting materials include any common steroid group such as bile acids, deoxycorticosterone, or vege­table sterols- For example, according to a patent issued to Pfizer. Yiadril may be prepared by the palladium reduc­tion of desoxycorticosterone followed by treatment with succinic anhydride and formation of t he sodium salt. The sodium salt solution is then sterilized by Seitz filtration.

Clinical Results. Viadril has been used at the University of California School of Medicine in more than 130 operations involving 20 surgical pro­cedures. Not being exceptionally po­tent, it is most useful as a basal anes­thetic. As such, it is given intraven­ously followed b y administration of nitrous oxide and oxygen.

T h e new steroid is not considered pharmacologically similar to sodium pentothal, since t he former is an anes­thetic, the latter a hypnotic. Barbi-turates, used in nondepressant doses, produce only sleep. To be used as anesthetics, tney must ue given in doses sufficient to produce marked de­pression, particularly of respiration. With Viadril, the desirable therapeutic effects are produced by doses which do not bring about this depression.

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