Reza cyanosis

1. Cyanosis Presented by Dr. S. M. Monir hossain Intern doctor Khulna Medical College Hospital

2. Definition It is a clinical condition characterized by bluish or purple discoloration of skin and mucous membrane due to increased amount of reduced or deoxygenated hemoglobin ( Hb ) in the blood. Cyanosis is not seen until the amount of deoxygenated Hb is >5 g%

3. Types of cyanosis Peripheral cyanosis Central Cyanosis

4. Peripheral cyanosis It occurs due to localised reduction of blood flow on exposure to cold, causing capillary vasoconstriction. Also occurs in reduced cardiac output i.e. Heart failure or Shock. Peripheral cyanosis is also seen in peripheral vascular disease like Raynaud’s disease. Tongue is spared in peripheral cyanosis.

5. Central cyanosis This is either due to imperfect oxygenation of blood in lung or admixture of venous and arterial blood. It is evident when O 2 saturation falls below 80% to 85%. Central cyanosis is best evident in tongue. Tongue is not involved because tongue is always warm and circulation is good in tongue.

6. Mechanism of cyanosis

7. Mechanism of cyanosis

8. Mechanism of cyanosis

9. Where to look for cyanosis

10. Causes of Central Cyanosis In newborn: Birth asphyxia Intracranial hypertension, hemorrhage Oversedation (direct or through maternal route) Seizures Respiratory distress syndrome Meconium aspiration Pneumonia (sepsis) Pneumothorax Congenital diaphragmatic hernia Pulmonary hypoplasia

11. Causes of Central Cyanosis Defect in oxygenation of blood in lungs. Fibrosing alveolitis Severe pneumonia COPD Severe acute bronchial asthma Pulmonary infarction Shunt anomaly in heart (right to left) Transposition of great vessels Total anomalous pulmonary venous return Truncus arteriosus Tetralogy of Fallot Ebstein malformation of the tricuspid valve Tricuspid atresia

12. Causes of Central Cyanosis Heart failure/Cardiogenic Shock Polycythemia Methemoglobinemia High altitude (physiological)

13. Differences between central and peripheral cyanosis Points Central Peripheral Cyanosis Generalised Localised 2. Affected part Warm Cold 3. Application of warm Does not disappear Disappears 4. Oxygen Cyanosis may disappear in pulmonary case (Except in right to left shunt) Disappears 5. Tongue Always involved Never involved

14. There is no cyanosis in Severe anemia because Hb is low and fully saturated, leaving no excess deoxygenated Hb . Similarly in Polycythemia cyanosis may occur even in mild hypoxia.

15. When cyanosis is present only in the toes but not in the fingers, it is called Differential cyanosis . It is seen in PDA. In newborns, it can also occur in pre-ductal coarctation of aorta along with PDA. 

16. THANK YOU