ABSTRACT
The first neuromuscular stimulation was external. Patients whose diaphragm function is impaired may have it contracted by small cuff electrodes placed around the phrenic nerve. The level of stimulation increases with a ramp function, thus causing a ramp-like function in diaphragm contraction and lung inspiration. Patients who had lost the ability to contract their muscles, have their muscles stimulated by surface electrodes on the belly of the muscle. Stimulators have also been made small enough to be implanted next to the motor nerves that feed the muscles. Patients with problems voiding the bladder may have cuff electrodes placed around the nerves leading to the detrusor muscle that assists bladder voiding and also to the sphincter muscle that must relax for voiding. When the atrioventricular node fails to conduct, heart block occurs because excitation in the atria fails to conduct to the ventricles.
