In the article titled, “Mechanisms of hypoxemia” published in pages 47-60, issue 1, vol. 34 of Lung India[1], the paragraph under the sub-heading “The arterial/alveolar oxygen tension ratio (a-A oxygen tension ratio)” on page no. 58 is written incorrectly. The correct paragraph should appear as following:“A 65-year-old patients of COPD presented in the emergency with acute exacerbation. His ABGs is showing a PaO2 of 40 mmHg and a PaCO2 of 55 mmHg on FiO2 28%. What should be the FiO2 to raise PaO2 to 60 mmHg?PAO2 = FiO2 (PB − PH 2O) − PaCO2/R.=0.28 (760 − 47) − 55/0.8.=131.PaO2/PAO2 = 40/131 = 0.30.60/New PAO2 =0.30Required FiO2 = 0.37 or 37%.”