  The relativistic method of moments is one of the most successful approaches
to extract second order viscous hydrodynamics from a kinetic underlying
background. The equations can be systematically improved to higher order, and
they have already shown a fast convergence to the kinetic results. In order to
generalize that method, we introduced long range effects in the form of
effective (medium dependent) masses and gauge (coherent) fields. The most
straightforward generalization of the hydrodynamic expansion is problematic, or
simply ill-defined, at higher order. Instead of introducing an additional set
of approximations, we propose to rewrite the series in terms of moments
resumming the contributions of infinite non-hydrodynamics modes. The resulting
equations are consistent with hydrodynamics and well defined at all order. We
tested the new approximation against the exact solutions of the
Boltzmann-Maxwell-Vlasov equations in $(0+1)$-dimensions, finding a fast and
stable convergence to the exact results.
