Final answer:
The third step in the jaw-thrust maneuver without head extension is to use the fingers to lift the jaw, which helps in opening the airway for patients who may have a spinal injury.
Step-by-step explanation:
The third step in the jaw-thrust maneuver without head extension is to use the fingers to lift the jaw. This technique is used to open the airway in a patient who may have a spinal injury and for whom neck movement would be contraindicated. The procedure involves gently lifting the lower jaw with the fingers while stabilizing the head and neck to ensure no further injury occurs. It is crucial in providing an open airway for patients who are unconscious or have compromised respiratory function, especially when endotracheal intubation is not immediately available or indicated.