What causes myopotential inhibition of a pacemaker?

What causes myopotential inhibition of a pacemaker?

In addition to electrocautery, other forms of electrical activity may also interfere with pacemaker function. Succinylcholine causes diffuse muscle fasciculations in many patients, and these fasciculations are only partially prevented by defasciculating doses of nondepolarizing muscle relaxants. During muscle fasciculations, depolariz-ing membranes produce electrical discharges, which may inhibit a pacemaker. A unipolar pacemaking system’s positive pole (anode) is in the generator case, which is usually located in close proximity to the pectoralis major muscle. This can result in myopotential inhibition.

Asystole following the administration of succinylcholine is best treated by placing a magnet over the pacemaker gen-erator to temporarily convert the pacemaker to an asyn-chronous mode. Alternate means of pacing include external pacemakers and temporary transvenous pacemakers (including specially designed pulmonary artery catheters).