  We present a fully dynamical model to study the chiral and deconfinement
transition of QCD simultaneously. The quark degrees of freedom constitute a
heat bath in local equilibrium for both order parameters, the sigma field and a
dynamical Polyakov loop. The nonequilibrium evolution of these fields is
described by Langevin equations including dissipation and noise. In several
quench scenarios we are able to observe a delay in the relaxation times near
the transition temperature for a critical point as well as a first-order phase
transition scenario. During the hydrodynamical expansion of a hot quark fluid
we find a strong enhancement of thermal fluctuations at the first-order
transition compared to a scenario with a critical point.
