Patients at risk for complications:
(1) older patients
(2) more severe disease
(3) history of complications during previous episodes of the acute chest syndrome
Complications of the acute chest syndrome:
(1) acute respiratory failure
(2) neurologic events (altered mental status, seizures, intracranial hemorrhage, anoxic injury, etc.)
(3) complications of bronchoscopy (transient hypoxemia, laryngospasm, pneumothorax)
(4) sepsis
Acute splenic sequestration is a complication of sickle cell anemia that may occur at the same time as the acute chest syndrome.
Risk factors for development of respiratory failure (Vichinsky et al, page 1860):
(1) radiographic evidence of extensive lobar involvement ("whiting out")
(2) platelet count < 200,000 per µL at diagnosis (low normal to thrombocytopenia)
(3) history of heart disease
Some patients progress to acute respiratory failure with severe hypoxemia and an extensive pulmonary infiltrate. This is associated with a high mortality rate.
