Cyanotic Spells

Just an introduction.

1. CYANOTIC SPELLS - PRISCILLA- INTRODUCTION

2. A 7 month old girl presents to the outpatient clinic because of recurrent episodes of perioral and extremity cyanosis over the preceding 2 days. Each episode lasts 2 to 3 hours, occurs two or three times per day, and seems most prominent on the hands and feet. There has been no cyanosis of the chest or abdomen. Her skin colour varies from blue to a sunburned pink. The girl has been afebrile, with no cough, congestion, wheezing or symptoms of any illnesses. She has been formula-fed for the preceding 5 weeks, drinking 6-8 Oz four to five times per day.

3. On physical examination, the infant is afebrile, has normal vital signs. There is no respiratory distress and her lungs are clear to auscultation. She has a regular cardiac rhythm with no murmurs. Abdominal and neurological examinations yield normal results. Diagnostics tests, including a complete blood cell count, complete metabolic panel, chest radiograph and echocardiography was done. Further questioning and a laboratory test reveal the diagnosis.

4. CYANOSIS DEFINITION: Cyanosis specifically refers to a bluish tone visible in the mucous membranes and skin when desaturated or abnormal hemoglobin is present in the peripheral circulation. Central cyanosis occurs when poorly oxygenated blood enters the systemic circulation where there is “right -to-left” shunt and it may occur within the heart or in the pulmonary circulation itself. When there is primary parenchymal lung disease or neurologic disease causing alveolar hypoventilation , an “intrapulmonary” right-to- left shunt can occur.

5. CAUSES OF CYANOSIS Abnormal hemoglobins may be fully saturated with oxygen, yet unable to release it to the tissues like Methemoglobinemia . Anemia when H b = 3-5gm/dl cyanosis will be visible. Typical cyanotic lesions are the “five Ts ” of congenital heart disease: tetralogy of Fallot , transposition of the great vessels, total anomalous pulmonary venous return, tricuspid atresia, and truncus arteriosus but others may also be present.

6. Pulmonary diseases like : upper airway obstructive problems (croup, epiglottitis) lower airway diseases (bronchiolitis, asthma, cystic fibrosis , pneumonia with lobar consolidation). Foreign body

7. CYANOTIC SPELL DEFINITION : Acute hypoxemic attack which represents a true emergency and initial treatment is crucial to long term outcome . Also called as Hyperpnoeic spell, Hypoxic spell, Anoxic or blue spell, Hypercyanotic spell or Tet spell . Usually occurs in cyanotic congenital heart diseases with reduced pulmonary blood flow . A pediatric emergency- a typical episode can lead to death. Peak incidence between the age group of 2-6 months. Episodes beyond the age of 2 years are rare .

8. About 40% of pts. with cyanotic congenital heart disease & decreased blood flow develop this spell. Usually, the underlying diagnosis is tetralogy of Fallot . A typical episode begins with a progressive increase in rate & depth of respiration, resulting in paroxysmal hyperpnoea , deepening cyanosis , limpness & syncope, convulsions, CVA & even death . The spells are usually self-limited and last for about <15-30 mins duration .

9. CYANOTIC SPELLS are classically found in :- Tetralogy of Fallot Double Outlet Right Ventricle (DORV) w ith VSD with PS Tricuspid Atresia Single Ventricle with Pulmonary Stenosis Transposition of great arteries Eisenmenger’s Syndrome

10. Precipitating Factor C ommon in the early morning, shortly after the patient awakens or following any exertion. Prolonged agitation and crying are also cited as precipitants. Also , noxious stimuli such as phlebotomy or a bee sting or any circumstance which leads to enhanced catecholamine output can precipitate a spell in a susceptible child. A decrease in systemic vascular resistance (SVR) during exercise, bathing or fever, dehydration, tachypnoea , tachycardia due to any cause potentiates a right-to-left shunt and precipitates hypoxemia. In such cases ( tet spells), the absence of a heart murmur is a worrisome indicator that pulmonary blood flow is severely compromised.

11. Differential Diagnosis Aortic stenosis Acute Respiratory Distress Syndrome Apnoea Bronchiolitis Foreign Body Ingestion Pediatric Patent Ductus Arteriosus Surgery Pneumonia Pneumothorax Pulmonic Valvular Stenosis Sickle Cell Anemia