When giving abdominal thrusts, how should the responder position their hands?

When performing abdominal thrusts, the correct technique is to make a fist with one hand and place it just below the navel. This positioning is critical because it allows for the application of upward pressure, which is essential for dislodging an object blocking the airway in a conscious person. The thrusts are aimed at creating a sudden increase in intra-abdominal pressure, which, in turn, can force air from the lungs and expel the obstruction.

Positioning the fist just below the navel ensures that the thrusts are delivered effectively to the diaphragm, the muscle responsible for pushing air out of the lungs. Proper hand placement is crucial for maximizing the force applied while minimizing the risk of causing injury to the ribs or other internal structures.

In contrast, the other options do not provide the correct positioning for effective abdominal thrusts. For instance, placing one hand on the navel and one on the chest does not focus the force appropriately to dislodge an obstruction. Similarly, using two fingers against the ribcage or keeping both hands flat against the stomach would not properly apply the needed pressure to the diaphragm. Therefore, option B correctly outlines the appropriate hand positioning necessary for effective abdominal thrusts.