We investigate, using ab initio molecular dynamics simulations, the effect of temperature on the stability of pure, C and H doped, atomically thin gold nanowires. We show how thermal fluctuations lead to local instabilities that result in the rupture of the nanowires, and how appropriate impurities may help to stabilize these wires. We also show that when light impurity atoms, such as hydrogen, are incorporated in the Au nanowires, quantum effects will affect the nuclear dynamical evolution.