Last night I slept with the Oximeter clipped to my forefinger in preparation for the respiratory and expiratory lung tests at Papworth Hospital today. I went through the usual test and nothing much seems to change except the oxygen level in my lung blood has gone down from 95 to 92.5 which may or may not be as significant as the oximeter, which measures the level, can apparently, vary by up to 2%. However, having said that the consultant told me that they would know better in three months time when they measure the level again. Below 90 apparently is a point at which some ventilation intervention could be helpful. We will see.