1Professor, Department of pulmonary Medicine, ESI-PGIMSR, Basaidarapur, New Delhi-110015
2Senior Resident, Department of pulmonary Medicine, ESI-PGIMSR, Basaidarapur, New Delhi-110015
*Address for correspondence: Dr. Dipti Gothi Professor, Pulmonary Medicine, ESI-PGIMSR, Delhi Telephone No-+91-01125970860 E-mail: diptigothi@gmail.com
Online published on 30 June, 2018.
Daytime hypoxemia in chronic obstructive pulmonary disease (COPD) patients is common. The causes of daytime hypoxemia are varied and are linked to nocturnal breathing disorders. These nocturnal breathing disorders of COPD are: 1) obstructive sleep apnoea (OSA), 2) nocturnal oxygen desaturation (NOD) without CO2 retention and 3) nocturnal hypoventilation. OSA with COPD i.e. overlap syndrome is seen in overweight rather than obese patients. They do not have excessive daytime sleepiness unlike OSA alone hence it is easily missed. Continuous positive airway pressure (CPAP) is the treatment of choice in these patients. Nocturnal oxygen desaturation without CO2 retention is due to V/Q mismatch and is seen in those with respiratory COPD phenotype. Long-term oxygen therapy (LTOT) alone is adequate for patients who develop consequent daytime hypoxemia. Contrarily, daytime hypoxemia due to nocturnal hypoventilation is seen in systemic COPD phenotype and it responds to non-invasive ventilator (NIV) with LTOT. This review is aimed at deciding if CPAP, LTOT or NIV with LTOT is required in COPD patients with daytime hypoxemia.
