Dogliotti's principle

Dogliotti's principle: In epidural anaesthesia, the principle that the change of pressure from the ligamentum flavum to the epidural space can be identified by constant pressure on the piston of a syringe whilst advancing a needle into the patient's back, thus permitting identification of the epidural space.

The technique was described by Professor A. Mario Dogliotti in 1933, an Italian physician from the Institute of Surgical Pathology in Turin, Italy. This technique remains in use at present, and is commonly referred to the loss of resistance to saline technique or it's variation the loss of resistance to air technique.