Acute chest syndrome is suspected
Sepsis, osteomyelitis, or other serious infection is suspected
Priapism, aplastic<unk> , hypoxia, splenic sequestration
WBC >30K
Platelet <100K<unk>  is not under control after 3 rounds of analgesics in ED
<1yr old<unk>  is under control and patient can take oral fluids and medications
Ensure appropriate oral analgesics are available
Provide home care instructions
Ensure resource for follow-up
Vaso-occlusive pain crisis
Acute arterial ischemia
Bony infarction
Crotaline envenomation
Dactylitis
Neurogenic shock
Avascular necrosis of femoral head
Heat stroke