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ULY CLINIC

ULY CLINIC

6 Julai 2025, 08:43:37

Cyanosis

Cyanosis
Cyanosis
Cyanosis

Cyanosis is a bluish or bluish-black discoloration of the skin and mucous membranes resulting from elevated levels of unoxygenated hemoglobin in the blood. It may develop acutely or gradually, and is a key clinical sign of cardiopulmonary or vascular compromise.


Classification

Type

Characteristics

Central cyanosis

Inadequate oxygenation of arterial blood. Affects mucous membranes (lips, tongue, conjunctiva). Caused by right-to-left cardiac shunts, pulmonary disease, or hematologic conditions.

Peripheral cyanosis

Due to vasoconstriction or low cardiac output. Localized (fingers, toes, nose, ears); spares mucous membranes. Caused by cold exposure, shock, or vascular occlusion.


Pathophysiology

Cyanosis occurs when oxygen saturation drops below 80% or PaO₂ is severely reduced. Contributing factors include:

  • Hemoglobin concentration

  • Cardiac output

  • Arterial oxygen tension (PaO₂)

It is less visible in dark-skinned individuals, where examination of mucous membranes and nail beds is more reliable.


Emergency Interventions

  • Acute localized cyanosis + ischemia:➤ Keep limb dependent, protect from trauma, do not massage.

  • Central cyanosis (e.g., due to pulmonary failure, shock):➤ Rapid ABC assessment➤ Maintain airway, assist breathing (oxygen), support circulation (IV fluids, monitoring)


History and Physical examination


History focus

  • Cardiac, respiratory, hematologic conditions

  • Medication use, smoking, recent surgeries

  • Triggering factors (cold, exercise, stress)


Physical Examination

  • Vital signs: RR, HR, BP, SpO₂

  • Skin/mucosa: Distribution, coolness, pallor, ulceration

  • CV: Heart sounds, gallops, murmurs, peripheral pulses, capillary refill

  • Respiratory: Rate, rhythm, effort, accessory muscle use, adventitious sounds

  • Neuro: LOC, headaches, motor/sensory function

  • GI/Abdomen: Hepatomegaly, ascites, anorexia, weight loss


Medical causes of cyanosis

Condition

Cyanosis Type

Key Features

Arteriosclerotic occlusive disease

Peripheral

Weak leg pulses, claudication, ulcers, gangrene

Bronchiectasis

Central

Foul sputum, hemoptysis, clubbing, coarse crackles

Buerger’s disease

Peripheral

Cold exposure-related, ulcers, weak pulses, aggravated by smoking

COPD

Central

Productive cough, barrel chest, dyspnea, wheezing, clubbing

DVT

Peripheral

Local tenderness, edema, positive Homans’ sign

Heart failure

Central/Peripheral

Fatigue, edema, JVD, crackles, gallops, hepatomegaly

Lung cancer

Central

Hemoptysis, weight loss, dullness, mediastinal shift

Peripheral arterial occlusion

Peripheral

Sudden cyanosis, pain, pulselessness, pallor

Pneumonia

Central

Crackles, fever, purulent sputum, pleuritic chest pain

Pneumothorax

Central

Sudden chest pain, absent breath sounds, JVD, asymmetry

Polycythemia vera

Central-appearing

Ruddy complexion, headache, pruritus, hepatosplenomegaly

Pulmonary edema

Central

Frothy sputum, dyspnea, crackles, gallop, confusion

Pulmonary embolism

Central

Sudden dyspnea, hemoptysis, pleuritic pain, JVD, paradoxical pulse

Raynaud’s disease

Peripheral

Cold-induced triphasic color changes (white → blue → red)

Shock

Peripheral

Cold, clammy skin, weak pulse, hypotension

Sleep apnea

Central

Associated with pulmonary HTN, right heart failure


Pediatric considerations

  • Common causes: Congenital heart defects, airway obstruction, cystic fibrosis, epiglottitis

  • Circumoral cyanosis may precede generalized cyanosis.

  • Acrocyanosis (hands/feet) in neonates may occur with cold or crying.

  • Management: Oxygen therapy, minimal stimulation, prompt cardiopulmonary evaluation.


Geriatric considerations

  • Cyanosis may present even with mild decreases in perfusion due to reduced vascular reserve.

  • Be vigilant for silent hypoxemia in older adults.


Management strategies


Supportive measures

  • Supplemental oxygen:

    • 2 L/min for COPD patients (avoid CO₂ retention)

    • High-flow for acute distress

  • Positioning: Upright to ease breathing

  • Medications: Diuretics, bronchodilators, antibiotics, vasodilators as appropriate


Investigations

  • Arterial blood gas (ABG)

  • Complete blood count (CBC)

  • Chest X-ray

  • ECG, echocardiography

  • Doppler or CT angiography (vascular obstruction)


Patient Counseling

  • Educate on warning signs and the importance of early medical attention.

  • Teach safe oxygen use at home, especially in chronic lung disease.


References

  1. Khemani RG, Patel NR, Bart RD, Newth CJ. Comparison of the pulse oximetric saturation/fraction of inspired oxygen ratio and the PaO₂/fraction of inspired oxygen ratio in children. Chest. 2009;135(3):662–668.

  2. Thomas NJ, Shaffer ML, Willson DF, Shih MC, Curley MA. Defining acute lung disease in children with the oxygenation saturation index. Pediatr Crit Care Med. 2010;11(1):12–17.

  3. Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. Nelson Textbook of Pediatrics. 21st ed. Philadelphia: Elsevier; 2020.

  4. Fuhrman BP, Zimmerman JJ. Pediatric Critical Care. 5th ed. Philadelphia: Elsevier; 2017.

  5. Papadakis MA, McPhee SJ, Rabow MW. Current Medical Diagnosis & Treatment 2024. New York: McGraw-Hill Education; 2024.

  6. Guyton AC, Hall JE. Textbook of Medical Physiology. 14th ed. Philadelphia: Elsevier; 2020.

  7. Volpe JJ. Neurology of the Newborn. 5th ed. Saunders Elsevier; 2008.

  8. Bickley LS. Bates’ Guide to Physical Examination and History Taking. 13th ed. Philadelphia: Wolters Kluwer; 2020.

  9. American Heart Association. Pediatric Advanced Life Support Provider Manual. AHA; 2020.

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