Pacemaker mode
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Physics principle used
The external pacemaker applies a squared waveform of variable frequency and
intensity to the heart in order to stimulate heartbeats. In a normal heart, the heart
beats as follows: the sinoatrial node, located in the right atrium, stimulates the
heart's contraction. It is controlled by the parasympathetic system that by freeing
acetylcholine, performs a depressor effect while a sympathetic innervation, when
stimulated, produces noradrenaline, which accelerates the rhythm. This potential
is then propagated through the atrial myocardium and then reaches the second
most important system center, the atrium-ventricular node, also located in the right
atrium, which transmits the potential to the ventricles through the atrium-ventricular
and its branches.
The pacemaker uses electrical stimulation to reproduce or regulate the heart's
rhythm.
Its function is to supply pulses in order to stimulate the heart. These pulses have
two characteristics that must be adjusted: The number of pulses per minute (PPM)
and the strength of the current (mA). The pacemaker works in two modes: fixed or
on demand (synchronous).
Warnings
The DualMax has a patient impedance meter that delivers shocks in 25 to 300
Ohms impedances.
If a cable or conductor is suspected of being ruptured, avoid using the
equipment due to possible risk to the operator.
Prolonged use of external pacemaker may cause erythematous skin.
In this Pacemaker mode, only the SOUND of the HIGH PRIORITY AND
MEDIUM PRIORITY alarms are disabled.
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