An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Siegenthaler A, Eichenberger U, Schmidlin K, Arendt-Nielsen L, Curatolo M.Siegenthaler A, et al.Anesth Analg. 2010 Mar 1;110(3):923-7. doi: 10.1213/ANE.0b013e3181cbd8f4.Anesth Analg. 2010.PMID: 20185669Clinical Trial.