Here are a few Frequently Asked Questions about the M Series® CCT.

Why Biphasic?

Quite simply, biphasic is better for your patients!
Biphasic shocks, allow for lower energy levels to be used to deliver the current (or flow of electricity) to the heart required for defibrillation. High energy, monophasic shocks, are associated with more post-shock dysfunction and complications in patients, due to the high peak currents required to deliver a monophasic shock.

Why use 200J? Isn't 360J better?

Energy is not what defibrillates the heart, average current (or current density) is.
Energy is a combination of Voltage, Current and Time(duration) of shock.

Energy can be changed by varying voltage, current or time.

So what happens when we change these variables?

Voltage
(or potential) is limited by the capacitor in the defibrillator. Any defibrillator has a set amount of electrical energy that it can store for a shock. ZOLL defibrillators have the largest capacitors.

Time
The time of the shock can be varied, however, longer shock times are associated with post shock dysfunction also. Long shock times reduce the average current applied because the whole time the shock is applied, the current level decays.

Current
Current is limited by the patient's resistance or impedance. Ohm's Law states, the higher the patient's resistance, the more voltage is required to pass the energy through at the same flow rate.

All current is not the same and it is not constantly delivered; It decays. The pattern of delivery (or waveform) counts. It is the rate of decay and length of shock that effects the amount of harmful high peak current required to generate the current density (or average current) required.

We need to deliver current in such a way that rapid decay of the current does not occur and therefore a high peak (or initial) current is not required. That is the basis of using a rectilinear waveform.

You can see that units that vary time to increase the number of Joules are really dealing in a false economy and that high energy does not equal high current.

Why use electrodes rather than paddles?

  • Reduce the time to first shock
  • Provide defibrillation and pacing through one mechanism
  • Simplify and speed the use of defibrillation and external pacing together
  • Increase operator safety during defibrillation
  • Reduce potential for inconsistent/inaccurate paddle placement or paddle pressure
  • Being able to use all features on your defibrillator such as Real CPR help and See Thru CPR
  • Being able to fully use self checking features

Are you able to shock conscious ventricular tachycardia (VT)?

The decision over whether to shock is always in the hands of the clinician. ZOLL defibs will shock if the decision is made to procede with this course of treatment if the clinician wishes to do so.

How do I upgrade my parameters?

ZOLL units are often upgradable, however the unit will have to be sent back to ZOLL to have the relevant modules switched on internally. Once this is done, you are free to plug in the appropriate probe for measurement of the parameter.

Is the M Series available with invasive lines?

The M Series® CCT units do have invasive lines as an optional parameter. This upgrade needs to be performed in the ZOLL service center. Standard M Series units cannot be upgraded to include invasive lines.

I have an AC unit, but need to use DC power? Can it be done?

DC inverters are available to convert AC units for use with DC power sources. If you have a DC unit and wish to use it with AC power, a permanent conversion can be performed at ZOLL's service centre.