A chronic smoker with emphysema demonstrated increased air trapping at the end of expiration. Which of the following statements about this patient is false?
  1. This condition is called auto-PEEP
  2. This can be corrected by altering mode of ventilation.
  3. This condition indicates impending rupture of a bulla.
  4. This can be corrected by a simple surgical procedure.

Answer: The answer is (d). Auto-PEEP is the development of end expiratory pressure caused by limitation of airflow in emphysema. The level of auto-PEEP can be estimated clinically by altering the mode of ventilation. Auto-PEEP is also called air trapping. High auto-PEEP can cause barotrauma. It can lead to rupture of bullae. In such situations, increasing the time for expiration helps.