Useful Poison

"A fantastic poison vaguely connected with South American Indians and detective novels" was Dr. Harold R. Griffith's first idea of curare (rhymes with safari). But in last week's Canadian Medical Association Journal, the Montreal doctor tells how he changed his mind, pioneered the use of curare to relax tense muscles during operations.

Death in Jigtime. Curare's "poisonous reputation" began in 1595 when Sir Walter Raleigh sailed up the Orinoco and found the jungle Indians killing game with blow pipe darts dipped in black, tarry stuff (curare) cooked up from native plants (see cut). Its reputation was not improved when 19th-Century experimenters found that curare victims die from asphyxia caused by paralysis of their breathing muscles. Time: a few seconds.

In 1938 Richard C. Gill brought back a big supply of curare from the jungles, hoping it would help spastic paralysis (TIME, July 22, 1940). It was not much help, because its effects are transient. But doctors soon began to use curare to pre vent bone breaking in metrazol shock treatments for insanity.

Dramatic Relaxation. Two years ago, Dr. Griffith began using curare on patients (especially abdominal cases) whose muscles remained tense in spite of general anesthesia. He was delighted at the "dramatic and complete relaxation" produced by the contents of one 5-cc ampoule injected into a vein. The effects are at maximum in five minutes, usually last 20 minutes.

Curare does not act on the big nerve centers. It acts by breaking the connection between the nerve ends and the muscles they serve. First muscles affected are those of the head and neck; then the limbs are paralyzed, then the abdominal muscles, last of all the diaphragm and between-rib muscles which do the work of breathing. (The danger of the drug is that just a little more than enough to relax the abdominal muscles may paralyze breathing--therefore only expert anesthetists should use it.) Besides relaxing skeletal muscles, curare contracts the gut, making it easy to handle and replace.

Dr. Stuart C. Cullen of the University of Iowa, a member of the Board of Directors of the American Society of Anesthetists, has applied Dr. Griffith's findings to 800 patients. Dr. Cullen gives curare in every abdominal operation where relaxation is essential, prolongs the effects by repeated small doses.

Dr. Cullen finds that, with curare, a surgeon can operate while the patient is in a light plane of anesthesia, thus reducing risk and speeding recovery from the anesthetic. He has even used it to keep a case of lockjaw from getting tense. But, he says, "complete and unqualified recommendation of the drug is withheld pending further clinical and laboratory investigation."

This file is automatically generated by a robot program, so reader's discretion is required.