Types of Cyanosis: Central vs. Peripheral

Recognising Cyanosis Types: Causes, Risk Factors & Diagnosis

Peripheral and central cyanosis are similarly recognised with the particular skin discolouration. In contrast, both types of cyanosis can be differentiated based on their affected areas of the body and underlying risk factors.   

Introduction

Cyanosis etymologically derives from "kyanos," a Greek word that refers to the dark blue colour. It is defined by mucous membrane discolouration and an abnormal bluish tone of the skin.

This blog examines different types of cyanosis and compares underlying risk factors, characteristics to determine accurate treatment and diagnosis. Moreover, it highlights similarities, symptoms of central and peripheral cyanosis, and their treatment.   

What is Cyanosis? How does it occur?

Cyanosis is a pathological disease that causes dark blue discolouration of the mucous membrane and the skin. The underlying disease occurs due to an increased, abnormal or reduced haemoglobin in the blood vessels. Haematological parameter alterations, keratinisation, extended skin pigmentation, capillary density, renal and pulmonary functional changes influence cyanosis fluctuations.   

Cyanosis appears in the thin overlying dermis and rich superficial vein areas. The most common affected areas are the skin, lips, tongue, gums, and ends of toes, earlobes and fingers. For dark skin, this disease appears on the tongue, lips, fingertips, and around the eyes.        

What are the Three Main Types of Cyanosis?

There are three main types of cyanosis: central, peripheral, and differential cyanosis.  

1. Central Cyanosis

The type of cyanosis is a bluish discolouration of visible mucous membranes and body areas, including lips, mouth and tongue. Central Cyanosis indicates problems of abnormal or deoxygenated haemoglobin and gaseous exchange.      

2. Peripheral Cyanosis

Peripheral cyanosis is a purple or bluish discolouration on fingertips, hands and toes. Apart from the distal extremities, it can sometimes occur in periorbital and circumoral areas.

3. Differential Cyanosis

Differential cyanosis indicates serious cardiopulmonary problems that cause asymmetrical bluish colour between the lower and upper extremities. This type of cyanosis requires urgent medical attention to manage serious complications such as cardiac failure, stroke, and pulmonary hypertension.     

What are the Major Differences Between Peripheral and Central Cyanosis?

The primary difference between the two types of cyanosis is that in peripheral cyanosis, blue colourisation is easily localised and affected by cold. Conversely, central cyanosis is defined as generalised bluish discolouration. The table below represents major differences between central and peripheral cyanosis:

What Symptoms are Associated with Different Types of Cyanosis?

The primary symptom of cyanosis is skin discolouration, a bluish tone in particular body parts. All types of cyanosis reflect some common symptoms, which are:

• Numbness
• Low body temperature
• Wheezing
• Coughing
• Breathing difficulties
• Fatigue or extreme tiredness
• Headache

The central cyanosis patients may experience some other symptoms, including:  

• Blue skin variation, such as discolouration in lips, fingers, tongue and toes
• Chest Pain
• Fever
• Fainting
• Sweating profusely
• Grasping for breathing issues

On the contrary, Peripheral cyanosis drives different symptoms, which are:

• Purple or bluish discolouration in fingers and toes
• Absent clubbing
• Low pulse volume  
• Discolouration disappears with warming and massage
• Absent dyspnea  
• Sudden pain in hands, feet, legs
• Concentration difficulties
• Difficulty breathing

Similarly, differential cyanosis indicates some recognisable symptoms, including:  

• Blue-toned discolouration mainly in legs and feet compared to hands
• Enlargement of fingertips
• Breathing difficulties
• Abnormal heart sound

How to Manage Central and Peripheral Cyanosis?

Cyanosis patients and their family members need to be aware of treatment options and risk factors to control the progression of different types of cyanosis. Apart from antibiotic medicines, surgery, oxygen therapy and medications, here are some medical tips to follow:   

• Physiotherapy is an evidence-based and effective intervention
• Muscle training
• Breathing exercises
• Quit smoking or tobacco use
• Control cholesterol level
• Maintain blood pressure
• Avoid immobility for a longer period
• Avoid extreme temperatures

Final Words

Peripheral cyanosis occurs due to lower blood pressure, Raynaud syndrome, and heart failure. It causes blue discolouration in the skin, fingers, and toes in cold temperatures.

Conversely, central cyanosis happens due to low-oxygen blood, abnormal haemoglobin, and gaseous exhalations.

It affects core organs, the mucous membrane, hands, legs, and fingernails. All types of cyanosis have common symptoms, including fever, breathing issues, blue skin, and fatigue.