Etiology of hypoxia in patients with SCD
| Mechanism of hypoxia . | Causes in SCD . |
|---|---|
| Hypoventilation | SDB (OSA, upper airway obstruction) Thoracic splinting due to chronic pain Restrictive pulmonary disease Reduced chest excursion due to hepatomegaly Central hypoventilation (eg, due to excessive use of narcotics) |
| Diffusion impairment | SCD-associated interstitial lung fibrosis PH Pulmonary vascular disease |
| Shunt | Intracardiac shunt (eg, ventriculoseptal defect) Extracardiac shunt Arterial-venous malformations Intrapulmonary shunt (eg, due to consolidation or atelectasis resulting in decreased perfusion to affected area) |
| Ventilation-perfusion inequality | Chronic VTE ACS Plastic bronchitis Obstructive lung disease without asthma Chronic airway inflammation due to asthma |
| Mechanism of hypoxia . | Causes in SCD . |
|---|---|
| Hypoventilation | SDB (OSA, upper airway obstruction) Thoracic splinting due to chronic pain Restrictive pulmonary disease Reduced chest excursion due to hepatomegaly Central hypoventilation (eg, due to excessive use of narcotics) |
| Diffusion impairment | SCD-associated interstitial lung fibrosis PH Pulmonary vascular disease |
| Shunt | Intracardiac shunt (eg, ventriculoseptal defect) Extracardiac shunt Arterial-venous malformations Intrapulmonary shunt (eg, due to consolidation or atelectasis resulting in decreased perfusion to affected area) |
| Ventilation-perfusion inequality | Chronic VTE ACS Plastic bronchitis Obstructive lung disease without asthma Chronic airway inflammation due to asthma |
OSA, obstructive sleep apnea; SDB, sleep-disordered breathing.