Even as Tamil Nadu faces medical oxygen shortage due to the surge in COVID-19 cases, the Greater Chennai Corporation is buying 3,000 oxygen concentrators, a move that is turning to be a life-saver for many who require oxygen support. With 900 machines already procured, the Chennai Corporation also supplies these to medical college hospitals which help them conserve the scarce liquid oxygen for critical patients. NDTV's Sam Daniel sent this report from the Government Stanley Medical College Hospital and the Communicable Diseases Hospital.