Basic Life Support Instructor Practice Test

To determine if rescue breaths were effective in an adult, observing for visible chest rise is key. When rescue breaths are delivered properly, they should cause the chest to rise and fall, indicating that air is entering the lungs. This is a vital sign that breath is being effectively delivered into the respiratory system, allowing for gas exchange to occur. Seeing the chest rise confirms that the airway is open, and air is moving into the lungs instead of escaping into the stomach or other areas. It's essential to ensure that the head is positioned correctly to maintain an open airway, maximizing the effectiveness of each breath delivered. Proper technique, including a good seal and the right volume of air, will enhance the chances of effective ventilation. Other options do not provide reliable indicators of effective rescue breaths. For instance, a whistle sound is not a typical indication of effective rescue breaths, and feeling the stomach expand might suggest improper breathing technique, where air is entering the stomach instead of the lungs. The victim responding verbally may occur in cases where adequate oxygenation has prompted improvement, but this is more of a late indicator rather than an immediate sign of effective rescue breaths.