The Department of Cardiorespiratory Physiology was started by Prof AS Paintal in 1954, being one of the four departments of the Institute. The department is unique and continues to be the only one of its kind in the country, offering integration of physiology into the clinical disciplines of pulmonary and critical care medicine.

The Department initially offered facilities for measurements of vital capacity and oxygen uptake by indigenously fabricated spirometry. Subsequently, facilities for cardiac catheterization were provided for study of pulmonary haemodynamics in 1959. Prof SK Jain joined as Research Fellow and later as Professor in the seventies and headed the department till 1991. His research areas included lung receptor physiology and lung function testing. He upgraded the lung function testing facilities by adding tests of blood gas analysis, lung volumes and diffusion and lung mechanics. An Asthma Research Cell was started in 1977 in collaboration with the Institute of Nuclear Medicine and Allied Sciences (INMAS) headed by Dr KP Agrawal, Scientist at INMAS. He later joined the Department as Reader on deputation. The cell carried out pioneering work in understanding the biochemical basis of bronchial asthma and in development of body plethysmographic techniques for measuring airways conductance in humans and animal models. This work was carried further by Prof SK Chhabra who joined as Lecturer in 1988. Prof MB Dikshit joined briefly from 1993 to 1995 in the Department. Prof Chhabra has been the heading the department since then.

The Department was the first in the country to establish comprehensive facilities for investigating lung function and pulmonary haemodynamics in pulmonary diseases. It continues to provide high quality services in these areas for patients and for research. Research into various aspects of bronchial asthma, COPD, interstitial lung diseases and  lung function tests continue to be the thrust areas for the Department. It has contributed immensely to the field of epidemiology, pathophysiology and pathogenesis of these diseases with pioneering and well acclaimed work.

The Department is one of the constituent units of the Viswanathan Chest Hospital of the Institute and runs a clinical unit and provides state-of–the-art pulmonary function testing facilities. It provides on-request short-term training in the field of pulmonary function testing. The department is associated with the teaching and training of DM, MD and diploma students in pulmonary medicine.