Hi ! Good evening. I am Dr Shareef answering your query. As a case of COPD, you must be getting deprived of proper oxygen saturation in your body which might affect all the tissue including the eye, and so you might get short spells of temporary blindness. However, if the duration is prolonged as much as an hour, I would advise you to get your eyes examined by an ophthalmologist at the earliest possible to avoid any further complication. Also please get your blood sugar tested and blood pressure recorded as a routine. I hope this information would help you in discussing with your family physician/treating doctor in further management of your problem. Please do not hesitate to ask in case of any further doubts. Thanks for choosing health care magic to clear doubts on your health problems. Wishing you an early recovery. Dr Shareef.