A stretcher including an upper frame for mounting a lifter thereon, a front leg pivotably attached to the upper frame, a rear leg pivotably attached to the upper frame, a fixed caster attached to one end of the front leg, a swivel caster attached to one end of the rear leg, and an auxiliary swivel caster attached to the front leg, wherein the upper frame is vertically adjustable by folding the front and rear legs relative to the upper frame, and wherein the auxiliary swivel caster is positioned relative to the fixed caster such that the auxiliary swivel caster is in contact with the ground when the upper frame is fully lowered and the front leg is folded away from the rear leg, and the auxiliary swivel caster is out of contact with the ground when the upper frame is fully lowered and the front leg is folded toward the rear leg.