At first glance this one seems to fit under the catagory of science fiction, but it's for real.
The FDA this week approved LeGoo, a new gel that allows surgeons to temporarily halt blood flow during certain procedures.
The gel—which is liquid at room temperature and solid at higher temperatures—prevents blood from filling the surgical area without damaging blood vessels, which often occurs when surgeons use clamps or elastic loops. The gel can stop blood flow for up to 15 minutes and dissolves later on its own, according to FDA.
The agency based its approval on research that showed that LeGoo is biocompatible and non-toxic, and on a clinical trial that showed that the gel as safe and effective as vessel loops used during coronary artery bypass grafting surgery.
According to Christy Foreman, director of the Office of Device Evaluation in the FDA's Center for Devices and Radiological Health, LeGoo is "an innovative device that offers surgeons an additional aid during vascular surgery. The gel's unique properties may facilitate surgeries that entail the joining or grafting of blood vessels."
LeGoo is indicated for use in blood vessels that are four millimeters or less in diameter and below the neck. It is contraindicated for use on vessels that supply blood to the brain. Read more here. (Be aware that there is a video of the surgery on this site, so if you're squeamish, don't scroll down.)