A 42-year-old man presents to the ED with a 6-hour history of persistent, painful erection. He initially called NHS 111, who advised immediate ED attendance, but he attempted conservative measures at home, including cold compresses, without success.

Past medical history: sickle cell. No previous episodes reported.

On examination:

• Patient appears distressed and in significant pain
• Penis is erect, rigid, and tender
• The glans appears normal in colour
• Normal scrotal examination
• Soft, non-tender abdomen

Vital signs: RR: 22 SpO2: 96% on room air HR: 105 BP: 125/85 Temperature: 36.8°C

Local anaesthetic nerve block given. Urology are on call from home.

What is the most appropriate next step in management for this patient