cyanotic hands or peripheral cyanosis or blue hands at southeast asian, chinese male patient

blue bluish breathlessness cardiac central changes chronic color covid cyan cyanosis cyanotic dark discoloration discolored discolouration discoloured disease disorder erythema finger fingers fingertips hand hands healthy hypoxemia hypoxia ill lane liver lung pale pallor palm palmar palms peripheral problem purple red reddish redness respiratory skin smoker smoking stain stained unhealthy