Delta-wave inducer
A delta-wave inducer was a device used to induce delta waves to appear during an operation to keep the patient asleep; it also increased the body's natural endorphin production to help accelerate the healing process. 

In 2370, Bashir used a delta wave inducer on Jadzia Dax during the operation to remove the  symbiont and place it in its new host, Verad. ()

See also 
Alpha-wave inducer

External link
 

de:Deltawellenerzeuger
Medical equipment
Sleep