laryngospasm

An 8-year-old male presents after falling onto an outstretched hand. He has an obvious dinner fork deformity to the right forearm. X-ray confirms a fracture of the distal radius and ulna. You prepare for procedural sedation with ketamine while you reduce and splint the fracture. You run through the pre-sedation assessment and exam, then gather all medications and airway supplies. Once the ketamine is pushed you hear a high-pitched stridor and see the patient’s chest rise and fall irregularly as his oxygen saturation drops. What is the diagnosis and management?