ABSTRACT
The respiratory muscles operate as a vital “air pump” promoting effective
ventilation both at rest as well as under conditions of increased demand. Dysfunc-
tion or weakness may thus compromise ventilatory ability and capacity. In this
chapter, we will focus on neuromuscular conditions involving the respiratory
muscles that may be managed in the intensive care unit (ICU) arena. However,
in order to fully appreciate the pathophysiology of the specific conditions, key
common principles governing functional anatomy, physiology, and functional
assessment of the respiratory muscles will first be introduced.
