Final answer:
You should open the airway of an unresponsive and not breathing patient by A. doing the jaw thrust maneuver, especially if a spinal injury is suspected. For choking, the Heimlich maneuver may be necessary.
Step-by-step explanation:
If you arrive on scene to a car accident and are treating a 35-year-old patient who is unresponsive and not breathing, you should open his airway by A. doing the jaw thrust maneuver.
This technique is used to avoid potential neck and spine injuries that could be present due to the accident. If the jaw thrust maneuver does not open the airway, or if you are trained and it is safe to do so, you could use the head tilt-chin lift method.
However, before moving the patient's head or neck, it is imperative to suspect a spinal injury and handle the patient with extreme care.
For a choking patient, initial steps include encouraging them to cough and providing back slaps to help dislodge the object.
If these measures fail, the Heimlich maneuver may be performed. Remember, for an unconscious person who might require ventilation, air can be delivered to the lungs with the use of a bag-valve-mask, applying pressure to create the necessary gauge pressure to force air in.
In cases where the heart stops, cardiopulmonary resuscitation (CPR) can be performed, which involves chest compressions, to provide circulatory support until medical help is available or the patient recovers spontaneous circulation.