Control of breathing

Abstract

The first observation that the respiratory rhythm is generated in the brainstem was made by Galen, who observed that gladiators injured below the neck continued to breathe. The existence of a ‘noeud vitale’ in the medulla was proposed by Flourens in 1840. The conventional view on the control of respiration is that a respiratory rhythm is generated in a respiratory center in the brainstem and driven by carbon dioxide (CO2) and hypoxia. This view is not entirely correct, particularly not in the fetus and the neonate. Although there is a respiratory rhythm generator in the medulla, respiration is governed by a number of regulating mechanisms hierarchically arranged to generate respiratory activity and the magnitude and pattern of breathing movements in accordance with metabolic and other demands.100