Final answer:
PEEP improves patient oxygenation by preventing alveolar collapse. It maintains pressure in the lungs to counteract surface tension and promote lung compliance, thus ensuring effective gas exchange and oxygen absorption into the bloodstream.
Step-by-step explanation:
The function of Positive End-Expiratory Pressure (PEEP) is A) It can improve patient oxygenation by preventing alveolar collapse. PEEP is applied during mechanical ventilation to maintain alveoli open at the end of expiration, thus preventing alveolar collapse (atelectasis), which enhances gas exchange and improves oxygenation in the blood. This therapy is especially beneficial in cases of acute respiratory distress syndrome (ARDS) and other conditions where alveolar collapse is a risk.
By maintaining a minimum pressure within the lungs at the end of each breath, PEEP counteracts the surface tension of alveoli that leads to collapse, thereby promoting the lung's compliance and functional residual capacity. This is crucial because an adequate oxygen partial pressure must be maintained in the alveoli to ensure effective gas exchange across the respiratory membrane, where oxygen is absorbed into the bloodstream and carbon dioxide is expelled. PEEP does not affect the flow of gases through the vaporizer, push breathing circuit gases, influence the comfort of anesthetized patients' breathing, or accelerate the flow of gases at the beginning of the inspiratory cycle. Those functions are unrelated to the use of PEEP in mechanical ventilation.