An anaesthetic approach to achieve a long-lasting nerve block that eliminates pain sensation while not affecting motor function has been developed by researchers at the Children's Hospital Boston in the US.
The approach has worked in rats and if it works in humans it could be useful in a variety of medical applications, including providing a local anaesthetic for childbirth that would block pain without interfering with the mother's ability to push.
Researchers focused on surfactants, a subclass of so-called "chemical permeability enhancers" that enable drugs to spread more easily throughout a tissue.
Children's Division of Critical Care Medicine managing director Daniel Kohane said that surfactants made the anaesthetic better able to penetrate sensory nerves and in motor neurons the active drug gets trapped in the myelin, never entering the nerve itself.
"What we've discovered really is a new approach; the question now is to figure out the mechanism by which it works and look at the effects of other chemical permeability enhancers," Kohane said.
The study was funded by the National Institutes of General Medical Sciences.