¹The Fokker-Planck collision operator is here considered, corresponding to small angle scattering. For very energetic electrons, i.e. when namely the kinetic energy exceed the Coulomb logarithm ln Λ^† = ln , large deflections must be taken into account. Here λ_D is the Debye length. Indeed, the impact parameter b = r_e∕β_th^†2, which measures the mean effective distance between two colliding particles is always very large as compared to the classical electron radius r_e, since β_th^† ≪ 1. However, for very energetic electrons, the impact parameter may reach b = r_e, when electrons become highly relativistic. Consequently, since the potential energy is close to the kinetic energy, π∕2 deflections may occur much more frequently. Since this effect is beyond the Fokker-Planck approximation and only concerns a small fraction of the total number of electrons in the plasma, it is described by a source term S_R which becomes significative for electrons which runaway when the Ohmic electric field is large, like in the ramp-up phase or during a disruption.