hello there..thank you for query. COPD is mostly due to chronic smoking.In this disease the airway system is affected which results in chronic inflammation and thus further symptoms.The COPD lungs are not like healthy lungs so patient find it difficult to catch his breath.Anticholinergic drugs and steroids can be used to relieve symptoms. the other symptom which you mentioned(bluish discolouration of lower limbs)is either due to inadequate oxygenation(due to copd) or can be due to peripheral vascular disease which is also common in smokers.. i will highly recommend you to visit your treating physician and he/she will run some test on your husband. further i will highly advise him to quit smoking completely. thank you