Interactions between plasma and shock waves, both of which are produced by the gas-breakdown induced by a CO2 laser pulse, are observed via framing Schlieren visualization. The deformation of the plasma bubble is characterized using the ratio of the laser pulse energy to the ambient pressure, and the laser beam diameter. The energy conversion efficiency from the laser pulse to the blast wave is dependent to the ambient pressure while it is insensitive to the other parameters. The size and the deformation speed increased with the characteristic shock radius.