Three low-cost ventilators that could provide vital support during major healthcare emergencies involving large numbers of patients or casualties have been developed by UK anaesthetists.

These ventilators could also be used where resources are limited, such as in developing countries, remote locations or by the military, the researchers said.

To test the three prototype devices, a mechanical test lung was used to show that they would provide effective ventilation for patients who were unable to breathe unaided.

The devices were also tested over a range of lung volumes and compliances, which indicated that the oxygen consumption was considerably lower than that of the commercially available gas-powered ventilators.