Question

A person suffers punctures in his chest cavity in an accident, without any damage to the lungs. It's effect could be:

• A. Reduced breathing rate
• B. Rapid increase in breathing rate
• C. No change in respiration
• D. Cessation (stopping) of breathing

Answer 1

The correct option is D Cessation (stopping) of breathing

The movement of air into and out of the lungs is carried out by creating a pressure gradient between the lungs and the atmosphere. The pressure within the lungs is less than the atmospheric pressure so there is a negative pressure in the lungs during inspiration. During expiration, the pressure within the lungs is higher than the atmospheric pressure.
The punctures in the chest affects this pressure gradient maintained by the lungs and thus may cause cessation (stopping) of breathing.