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The Case of the Travelling Trochar
Kenneth Russell, Professor Emeritus, MIT, Cambridge, MA -- Design News, June 2, 2003
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"Ken, this *&#! thing is called a trochar. It's used in those belly-button surgeries." With these words I was handed what resembled a stainless steel bridge spike. The speaker was a lawyer client, and friend; a Canadian who had moved to West Virginia to help found a large law firm. He had called me in on a number of cases over a 20-year period. He said that he liked teachers as witnesses because they were used to explaining things in simple terms.
He went on to explain how the trochar was used in belly-button sterilizations in particular. The sharp point pierces the skin and acts as a guide for a fiber optic cable that is used to locate the fallopian tubes.
In the current case the surgeon could not locate the tubes and had to perform a conventional procedure. Shortly afterward the woman was back in surgery complaining of abdominal pain. During surgery, the sharpened end of the trochar had become detached and had remained in her abdominal cavity. The tip had been so loosely attached, that friction with the patient's organs during withdrawal resulted in the separation. Yet another surgery was performed and the errant tip removed.
The patient was understandably upset.
I was called in as consulting metallurgist to determine what happened. The answer was not hard to find. The tip was supposed to have been silver soldered in place, but had never been attached properly.
Silver solders also contain copper and zinc. They melt at a lower temperature than copper-zinc brazing alloys, which makes them easier to use. These alloys also flow beautifully and are a pleasure to use, as many artisans know. They are also strong and corrosion resistant.
Microscopic study of the errant tip showed that very little of the joining surface of the tip had ever been coated by the silver solder. The reason was some combination of improprieties in heating, cleaning, and fluxing. It was impossible to tell just what combination of these factors was at work. But, the tip was barely tacked in place.
Such rotten workmanship is inexcusable, especially in view of the high price of anything used in surgery. The trochar would have sold for a few dollars were it some sort of fashionable ornamental gee-gaw to put in an étagère. The price to the hospital was probably a hundred times greater. Non-destructive testing of the finished trochar by x-ray or ultrasonic techniques would have been simple and cost effective. Simply grasping the subject trochar by both ends and pulling would have shown it to be defective.
The plaintiff was obviously in line for a substantial settlement. But who was to pay? The manufacturer was obviously at fault, but how about the operating team members who did not realize the tip was missing? My client represented the insurer of the hospital and surgeon. He sent up a trial balloon in his office to the effect that there was so much postoperative gore that it would be easy to miss the tip. The trial balloon was quickly shot down, and I suspect that the hospital/surgeon had to bear a significant part of the settlement.
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