The change in the single breath carbon dioxide (CO₂)curve from "A" to "B" shown in the figure may be as a result of which of the following?

Question

Quizplus · Accepted Answer

The change in the figure shows an increase in phase 1 and a decrease in phase 2 of the single breath carbon dioxide curve (SBCO₂)curve.An increase in phase 1 may be caused by an increase in anatomical deadspace.This is possible as a result of increased airway obstruction or excessive positive-end-expiratory pressure (PEEP).Therefore,answers "B" and "D" cannot be correct.A decrease in phase 2 means there is a decrease in venous return or an increase in intrathoracic pressure.This could be caused by hypovolemia or an increased intrathoracic pressure as seen with increased mean airway pressures.Therefore,answer "A" cannot be correct.Answer "C" is a measure of increased intrathoracic pressure and is the correct answer.

The Change in the Single Breath Carbon Dioxide (CO2) curve

The Change in the Single Breath Carbon Dioxide (CO₂)curve