Peripheral Cyanosis

CLINICAL DIAGNOSTIC MANUAL

Peripheral cyanosis is a condition in which the skin and mucous membranes acquire a bluish colour due to decreased oxygenation of the blood in the extremities. This condition occurs when there is an insufficient amount of oxygen in the blood reaching the peripheral tissues, which can be caused by various factors, including circulatory and cardiac issues. Peripheral cyanosis can be a sign of serious diseases and requires appropriate medical evaluation to identify the underlying cause.

Pathology	Suspected Diagnosis	Confirmatory Diagnosis
Raynaud’s phenomenon	Episodes of bluish discolouration and pallor in the fingers, triggered by cold or stress.	Clinical history, physical examination, cold provocation tests.
Arterial obstruction	Severe pain, pallor, coldness, and cyanosis in a limb, absence of distal pulse.	Arterial Doppler ultrasound, angiography, physical examination.
Haemorrhage	Rapid decrease in blood volume, pallor, tachycardia, hypotension.	Complete blood count, coagulation tests, clinical history.
Low cardiac output	Fatigue, dyspnoea, oedema, peripheral cyanosis, hypotension.	Echocardiogram, blood tests (BNP, troponins), chest X-ray.
Sepsis	Fever, hypotension, tachycardia, confusion, peripheral cyanosis due to poor perfusion.	Blood cultures, blood tests (inflammatory markers), arterial blood gas analysis.