Anaesthesia Concerning pulse oximetry true is A Oxyhemoglobin and deoxyhemoglobin light absorption is equal at the isobestic point of 660nm B Measurements are accurate in the presence of high levels of bilirubin C Measurements are accurate in presence of carboxyhaemoglobin D Measurements are accurate in presence of pigmented skin. 💡 Explanation Concerning pulse oximetry true is ✓ Correct Answer: D. Measurements are accurate in presence of pigmented skin.