In an oceanic waveguide, local sound speed variations induce acoustic path changes (angles, amplitudes, delays, etc...). Using vertical arrays in emission and reception and double beamforming, it is possible, for each path, to jointly track these changes in term of travel-time (τ), reception angle (θr) and emission angle (θe). In order to perform ocean acoustic tomography using these observables, we build sensitivity kernels which link the variations of these observables, measured after double beamforming, to sound speed variations. The construction of these kernels is made in two steps. A first order Born approximation of the Green's function is firstly used to derive the Helmholtz equation and obtain the link between the variations of the sound speed distribution and the variations of the received signal. Then, a first order Taylor development in the (t,θr,θe) signal space leads to a linear relation between the variations of the received signal and the variations of the measured travel-time, eception angle and emission angle of each acoustic path after double beamforming. This paper establishes the mathematical expression of sensitivity kernels and results obtained with synthetic data are shown and discussed.