Understanding the Control of Breathing to Optimize Patient–Ventilator Interactions

Abstract

Control of breathing depends on a complex and intricate feedback control system that integrates both automatic and volitional aspects of ventilation. A “central pattern generator” integrates inputs from peripheral and central chemoreceptors, as well as receptors located in the lungs, airways, muscles, and joints, in conjunction with signals from various brain regions. The output of the central pattern generator—referred to as the respiratory drive—determines the characteristics of breathing, including magnitude, timing, and the specific effector muscles involved. Several conditions frequently encountered in critically ill patients modify the output of the central pattern generator in predictable ways. By understanding the control of breathing physiology, health care providers can utilize readily available clinical data to make informed predictions about the characteristics of the patient’s breath. This approach can significantly enhance the interpretation of ventilator waveforms and improve the evaluation and management of patient–ventilator interactions.