Rule out other causes of acute pain such as septic arthritis/osteomyelitis, acute chest syndrome, splenic sequestration, trauma. Check CBC and consider sending Hgb electrophoresis.
Begin concurrent therapy for sickling
Oxygen, IV hydration, treat hypothermia, correct acidosis if present
Consider transfusion to increase Hgb A content. If symptoms are severe or organ function is becoming compromised consider double volume exchange transfusion to achieve a Hgb S level < 30%. Treat anxiety and or depression if present.
Consider pain service or adolescent medicine consults

Assess Severity of Pain

Use Visual analog scale (VAS) or faces scale to aid in ongoing pain assessment. Initial assessment should determine the severity of symptoms to guide the dosing and route of opioid therapy.

UCSD Pediatric Pain Scoring System