A novel anaesthetic that can stop pain yet allows patients to retain movement has been discovered through a study using rats.
Normally anaesthetics that block pain will also restrict the body's motor function. But now a group of scientists have been able to design an anaesthetic which could alleviate pain only, whilst patients retain the ability to move.
The researchers studied a group of surfactants which help the distribution of anaesthetics spread more easily through tissue. When they tested different combinations of surfactants and pain relieving drugs, the scientists found one which relieved pain in rats for up to 7 hours but did not restrict body movements.
The team suggest this was possible because the surfactant only spread to the sensory nerves and could not penetrate the motor nerves used for movement. Although the study shows promise there is still much to be investigated. If the treatment is to be used in a medical scenario, a higher dose of surfactant would be needed. A high dose of surfactant however, is usually toxic. Therefore the special anaesthetic will need to be tested on larger animals before it is ready for human use.
If the drug can be designed for use in human patients, it could be used by women during childbirth helping them deal with pain whilst maintaining the use of their muscles.