A flexible isolator bag used to isolate a controlled therapeutic gas atmosphere about a human limb for the management and treatment of wounds and lesions, or an amputation, has a discharge port and a flexible manifold section providing an intake manifold which has an infeed port and inlet openings to the interior of the bag. A self-sealing zipper extends along part of the length of the bag. The bag is secured to the patient by adhesive tape applied to the rim of the open end of the bag. This rim is shaped to prevent a tourniquet effect.