Fuente: Wipo "digitalization" A clip apparatus for non-invasive peripheral arterial tonometry measurements includes a first clip member having a first surface configured to receive a first portion of a digit of a patient and a second clip member coupled to the first clip member and having a second surface configured to receive a second portion of the digit. The first clip member and the second clip member are configured to receive the digit in a digit space defined by the first and second surfaces. One of the first clip member or the second clip member is movable toward the other of the first clip member or the second clip member to generate pressure within the digit space. The clip apparatus also includes a uniform pressure applicator configured to uniformly distribute the pressure generated within the digit space to a dorsal portion of the digit and a volar portion of the digit.