Final answer:
The appropriate response for the injured child would be to splint the forearm, apply a cold pack, and transport non-emergently, as he likely has a Colles fracture which does not immediately threaten life but does require stabilization.
Step-by-step explanation:
The proper care for an 8-year-old boy who fell off a swing and is now complaining of left forearm pain with a deformity to the left wrist would be to splint the forearm and apply a cold pack before transporting non-emergently. This answer stems from the fact that the most likely injury following a fall onto an outstretched hand is a Colles fracture of the distal radius, which results in a characteristic "dinner fork" deformity of the forearm. Immediate concerns include possible compression of the artery to the forearm from swelling, which can lead to ischemia and potential damage to forearm structures, such as muscles and nerves associated with the humerus. However, there is no indication in the vital signs of a life-threatening condition that would necessitate high-flow oxygen or immediate advanced life support (ALS) intervention. Instead, stabilizing the injury for transport is appropriate.