Faced with a common postoperative problem, preventing thromboemboli (blood clots) without using blood thinners, Dr. Lazar Greenfield had to look outside of healthcare for a solution. He considered filters, but the only filters used up until that time tended to create more problems than they solved. Flat screen filters would only add to venous obstruction and provide a nidus for more thrombus – creating a situation every bit as serious as the one it was intended to prevent.
So, where could Dr. Greenfield look to find a workable design for his intravenous filter?
Would you believe the oil industry? Or that the original device was designed to keep people from stealing gasoline? In the unlikely event that you guessed either, you’d be right.
Dr. Greenfield consulted with Garman Kimmel, an inventor whose company manufactured machinery and valves for oil companies. When Greenfield explained the problem of pulmonary embolism to Kimmel, Kimmel immediately drew a parallel to similar problems in the oil industry with sludge buildup. Kimmel pointed out that, in the oil industry, a cone shaped filter was used that would funnel sludge towards the center while still allowing the oil to flow around it. The cone shaped filter worked better than flat filters because, like the flat blood filter, flat oil filters simply trapped all of the sludge in one place, eventually clogging the line. The cone filter forced the sludge to the center, allowing oil to flow around it.
The design of this cone shaped filter was borrowed from a device patented in the 1940s to prevent thieves from siphoning gasoline from a car’s tank. Between the two of them, Dr. Greenfield and Kimmel designed the Greenfield Filter. The device has gone through numerous iterations since then, mostly in the tools and techniques for inserting it. The concept of the device, itself, has essentially remained unchanged for over 30 years, and is still saving lives today. What other potentially life saving concepts may be waiting in other fields, industries, and disciplines, just waiting for someone like you to put two and two together?
Image source: http://www.wikidoc.org/index.php/Image:Mar07_090.jpg