An inflatable cushion includes top and bottom sheets. The top sheet is sealed to the bottom sheet in peripheral zones to define an inflatable chamber and an inflation inlet in fluid communication with the inflatable chamber. A resistance wire extends between the top and bottom sheets and at least across the internal width of the inflation inlet. The inflation inlet further defines an inflation aperture. The inflatable cushion may be inflated through the inflation aperture and sealed by applying an electrical current across the resistance wire.