A pressure-volume loop ventilator graphic shows no rise in pressure for the first 200 mL of delivered volume. What should the therapist do?

In this situation, when the pressure-volume loop reveals no rise in pressure for the first 200 mL of delivered volume, it indicates that the ventilator is unable to create sufficient pressure to initiate ventilation for that initial volume. This can often happen when there is inadequate recruitment of the alveoli or when the airways are partially obstructed, leading to ineffective ventilation.

Increasing Positive End-Expiratory Pressure (PEEP) is the correct action because it helps to prevent the collapse of alveoli at the end of expiration. By maintaining a certain level of pressure in the lungs, PEEP encourages further recruitment of collapsed or under-inflated alveoli, which can result in improved compliance and an increase in the amount of gas exchanged during mechanical ventilation. This can lead to a more effective pressure response as the ventilator delivers volume, improving the overall ventilation status of the patient.

Adjusting PEEP is particularly effective in patients with conditions such as acute respiratory distress syndrome (ARDS) or other forms of atelectasis, where maintaining lung expansion is crucial for effective gas exchange.