Final answer:
To correct a high PaCO₂ and low pH due to respiratory acidosis on a ventilator, it is appropriate to increase either the respiratory rate or tidal volume, with the main goal of helping the patient exhale more CO₂. The preferred choice given the options is to increase tidal volume to aid in blowing off excess CO₂.
Step-by-step explanation:
The question asks what adjustment should be made to a ventilator if the patient's blood gas shows a high PaCO₂ and a low pH, indicating a state of respiratory acidosis where there is too much CO₂ in the blood and the blood is too acidic. The goal of ventilatory adjustment is to help the patient blow off excess CO₂ and increase the pH to a more normal level.
The correct action would be to increase the respiratory rate and/or increase the tidal volume. Increasing the respiratory rate will allow the patient to exhale more CO₂ per minute, while increasing the tidal volume will allow the patient to exhale more CO₂ per breath. Often in clinical practice, both parameters may be adjusted to achieve the desired blood gas results.
Considering the provided options, the best answer would be: A) Increase tidal volume, although in practice, sometimes a combination of increasing both tidal volume and respiratory rate is used.