A multi-purpose patient support and transport apparatus is provided which includes a Trendelenburg mechanism and a novel guard rail assembly. The Trendelenburg mechanism is actuated by turning a handle in one direction. This allows a pneumatic spring connected between the seat and backrest assemblies to be fully contracted, thereby moving the backrest assembly to a Trendelenburg position. When the handle is turned in the opposite direction, the backrest may also be rotated downwardly, but is precluded from moving beyond the reclining position by a stop member which prevents the pneumatic spring shaft from moving entirely within the spring casing. The guard rail is mounted to the frame of the apparatus by a pair of pivot arms extending at an oblique angle with respect to the plane of the rail. This allows the rail to be stored under the frame when in the lowered position.