Sexual intercourse and respiratory failure.

Sexual activity is an important component of quality of life in patients suffering from chronic illnesses. To our knowledge, the effects of sexual activity on gas exchange in patients with respiratory failure have not been yet studied. To such an extent, we evaluated the oxygen saturation (SaO2), by a pulse oxymeter, during three different sexual performances in a 63-yr-old patient affected by chronic obstructive pulmonary disease (COPD) on long-term oxygen therapy (LTOT). The sexual performances were divided in four periods: basal, sex, 10 min after sex and relax. In each performance during sex, we observed a significant increase of either heart rate (HR) or SaO2, with the highest value of the latter achieved within the 10 min of the post-sex period. SaO2 returned to basal value (pre-sex) by the end of the relax period. We conclude that the observed improvement of SaO2 during sexual activity might be due to a better ventilation/perfusion ratio (V/Q) obtained for either an increase of ventilation (hyperventilation) and perfusion (tachycardia), without significant muscle expenditure.