ZOLL X Series Monitor Defibrillator Rev H - Manual (Page 30)

C HAPTER 1 G ENERAL I NFORMATION
1-18 www.zoll.com 9650-001355-01 Rev. H
Before charging the defibrillator, verify that the energy selected on the display is the desired
output.
Defibrillation takes priority over external pacing. Should the defibrillator be charged during the
administration of external pacing, the pacer turns off and the defibrillator charges to the
selected energy.
Pacing
Ventricular fibrillation does not respond to pacing and requires immediate defibrillation.
Therefore, the patient’s dysrhythmia must be determined immediately, so that you can employ
appropriate therapy. If the patient is in ventricular fibrillation and defibrillation is successful but
cardiac standstill (asystole) ensues, you should use the pacemaker.
Ventricular or supraventricular tachycardias can be interrupted with pacing, but in an
emergency or during circulatory collapse, synchronized cardioversion is faster and more
certain.
Pulseless electrical activity (PEA) can occur following prolonged cardiac arrest or in other
disease states with myocardial depression. Pacing might then produce ECG responses without
effective mechanical contractions, making other effective treatment necessary.
Pacing can evoke undesirable repetitive responses, tachycardia, or fibrillation in the presence of
generalized hypoxia, myocardial ischemia, cardiac drug toxicity, electrolyte imbalance, or
other cardiac diseases.
Pacing by any method tends to inhibit intrinsic rhythmicity. Abrupt cessation of pacing,
particularly at rapid rates, can cause ventricular standstill and should be avoided.
Noninvasive temporary pacing can cause discomfort of varying intensity, which occasionally
can be severe and preclude its continued use in conscious patients.
Similarly, unavoidable skeletal muscle contraction might be troublesome in very sick patients
and might limit continuous use to a few hours. Erythema or hyperemia of the skin under the
hands-free therapy electrodes often occurs; this effect is usually enhanced along the perimeter
of the electrode. This reddening should lessen substantially within 72 hours.
There have been reports of burns under the anterior electrode when pacing adult patients with
severely restricted blood flow to the skin. Prolonged pacing should be avoided in these cases
and periodic inspection of the underlying skin is advised.
There are reports of transient inhibition of spontaneous respiration in unconscious patients with
previously available units when the anterior electrode was placed too low on the abdomen.
The pacing rate determination can be adversely affected by artifact. If the patient’s pulse and
the heart rate display are significantly different, external pacing pulses may not be delivered
when required.
Artifact and ECG noise can make R-wave detection unreliable, affecting the HR meter and the
demand mode pacing rate. Always observe the patient closely during pacing operations.
Consider using asynchronous pacing mode if a reliable ECG trace is unobtainable.
Transcutaneous pacing should not be used to treat V FIB (ventricular fibrillation). In cases of
V FIB, immediate defibrillation is advised.