Vygotsky's social account of psychology is comprehensible when viewed in relation to his political views and his early work experience. A brief discussion of this context is therefore in order before explaining the details of his psychological stand- point.
1 Central cyanosis and its causes are all associated with peripheral cyanosis. 2  Decreased pumping of blood by the heart or reduced cardiac output. 3  This is seen in heart failure or circulatory shock. 4  Diseases of circulation like thrombosis or embolism. 5  Constriction of blood vessels of the limbs, fingers and toes.
1 Features of peripheral cyanosis therefore include peripheral vasoconstriction and bluish or purple discoloration of the affected area, which is usually cold. 2  Peripheral cyanosis is most intense in nail beds and may resolve with gentle warming of the extremity. 3  The mucous membranes of the oral cavity are usually spared.