Final answer:
The EMS provider should stabilize the neck and roll the patient over to secure a patent airway before removing the patient from the water with a backboard. Additional first aid measures, such as the Heimlich maneuver, may be applied once the person is safely out of the water and if needed.
Step-by-step explanation:
In the context of first aid and emergency response, when encountering an unconscious person with a potential neck injury face down in a swimming pool, the EMS provider's first step should be to stabilize the neck while rolling the patient over. This is critical to secure a patent airway and ensure the person can breathe. The procedure should be done very carefully to avoid further injury to the spine. Once the patient is face up and the airway is assessed and managed, assistance with additional rescuers can be used to float a backboard under the patient for safe removal from the water. It's important to prioritize these steps over immediate attempts at CPR or aggressive manipulation that can exacerbate the injury. This step-by-step process aligns with the realities of emergency medical care where securing the airway and protecting the neck from further injury are paramount.
If the patient was choking, the steps would include encouraging them to cough, delivering back slaps, and if necessary, performing the Heimlich maneuver to remove the obstruction. However, in the context of drowning, these steps occur post-rescue once the patient is out of the water if needed.