Acute Chest SyndromeAnemia, Sickle CellChest PainEmbolism, FatHemoglobin SC DiseaseAntisickling AgentsSyndromeLung DiseasesSickle Cell TraitAcute DiseaseHydroxyureaHemoglobin, SicklePainBlood TransfusionFetal HemoglobinRespiratory InsufficiencyPulmonary EmbolismHemolysisFeverLeukocytosisRetrospective StudiesTriageCohort StudiesAcute Coronary SyndromeEmergency Service, HospitalTomography, X-Ray Computed