To the Editor.—The article by Chessick et al, "Spasm and Operative Cholangiography" (Arch Surg 110:53, 1975) did not compare the incidence of spasm of the sphincter of Oddi occurring in the presence of fentanyl with that occurring under other narcotics.
Halogenated anesthetics are thought to be contraindicated by some in biliary surgery. Flammable anesthetics are no longer commonly used. Conduction anesthesia is seldom used alone in surgery in the upper part of the abdomen. This leaves only the nitrous oxide, narcotic, muscle relaxant combination, which is one of the safest anesthetic techniques known.
To single out fentanyl as the offending agent seems unfounded in light of so many other factors, such as instrumentation, irritating dyes, surgical trauma, and Bakes dilators.
The article repeatedly states, "At operation... agents used, included fentanyl." This is similar to the conclusion of an investigator who found a correlation between low protein intake and high