In a patient undergoing mechanical ventilation, what might contribute to respiratory alkalosis?

Hyperventilation is a significant contributor to respiratory alkalosis during mechanical ventilation. When a patient hyperventilates, the respiratory rate and/or tidal volume are increased, leading to an excessive expulsion of carbon dioxide (CO2) from the body. This reduction in CO2 concentration results in an increase in blood pH, leading to a state of alkalosis. In mechanical ventilation settings, this can occur if the ventilator settings are too aggressive or if the patient's natural breathing drive is stimulating excessive breath rate.

Understanding this process is critical for respiratory therapists, as managing ventilation settings and monitoring the patient's response is essential to maintaining acid-base balance. In cases where respiratory alkalosis occurs, it may be necessary to adjust the ventilator settings to allow for CO2 retention and correct the pH imbalance.