RECTILINEAR BIPHASIC
RECTILINEAR BIPHASIC WAVEFORM
RECTILINEAR BIPHASICRECTILINEAR BIPHASIC
DEFIBRILLATOR OPTION
DEFIBRILLATOR OPTION
DEFIBRILLATOR OPTIONDEFIBRILLATOR OPTION
General Information
General Information
General InformationGeneral Information
Introduction
M Series products are available with an advanced electrical design that provides a unique rectilinear biphasic waveform for
defibrillation and cardioversion. With this option, the electrical energy of the defibrillator is delivered in two successive current
(voltage) phases of opposite polarity. This type of defibrillation waveform is commonly called biphasic, as opposed to the
earlier monophasic damped sine wave common to most commercially available defibrillators.
The ZOLL M Series Rectilinear Biphasic Waveform Defibrillator Option produces a proprietary waveform designed for optimal
clinical performance and tested extensively in multi-center clinical trials. These clinical trials have demonstrated that the
waveform is clinically effective for both defibrillation and synchronized cardioversion.
This insert explains how the M Series Rectilinear Biphasic Waveform Defibrillator Option differs from the monophasic
damped sine wave output of other M Series units. It is to be used in conjunction with the M Series Operators Guide.
Important safety information relating to general use of the M Series is located in the Safety Considerations section of the
M Series Operators Guide.
M Series with Rectilinear Biphasic Waveform Defibrillator Option Indications for Use
WAVEFORM
WAVEFORM WAVEFORM
The ZOLL M Series Biphasic Option is to be used only by qualified medical personnel for converting Ventricular Fibrillation
(VF), a cardiac rhythm incompatible with life, and/or Ventricular Tachycardias (VT) to sinus rhythm or other cardiac rhythms
capable of producing hemodynamically stable heart beats.
In addition, this product is to be used in the synchronized mode only by qualified medical personnel to terminate Atrial
Fibrillation (AF) at lower energies and currents than monophasic defibrillators. A qualified physician must decide when
synchronized cardioversion is appropriate.
This product is also to be used in the synchronized mode only by qualified medical personnel to terminate Ventricular
Tachycardias (VT). A qualified physician must decide when synchronized cardioversion is appropriate.
The Rectilinear Biphasic Waveform (RBW) has been successfully tested in multi-center, prospective, randomized,
transthoracic defibrillator VT/VF and AF clinical trials, and proven to defibrillate and cardiovert adult patients at lower energies
and currents than existing monophasic devices. The M Series Biphasic Option incorporates a broad range of user selectable
energy settings some of which are lower than those used during those clinical trials.
There are currently no clinical studies related to the use of the Rectilinear Biphasic Waveform (RBW) in pediatric applications
or for direct defibrillation of the heart during open chest surgical procedures.
The AED or advisory function should only be used to confirm ventricular fibrillation in patients meeting the following clinical
criteria:
the patient should be unconscious and unresponsive.
the patient should be apneic (not breathing).
the patient should be pulseless.
WARNING
Do not use the units AED function on patients under 8 years of age.
(Per AHA Guidelines for Adult Cardiopulmonary Resuscitation and AED,
3-5, 1998).
9650-0209-01 Biphasic - 1 Rev. C
OPTION INSERT
Defibrillator Function
The M Series Rectilinear Biphasic Waveform Defibrillator
Option is a DC defibrillator capable of delivering up to 200
joules of energy. It can be used for defibrillation or in a
synchronized mode for Cardioversion using the R-wave of
the patients ECG as a timing reference. The unit operates
with external paddles, or disposable pre-gelled, MFE Pads
for defibrillation and cardioversion.
Energy Selection and Displays
Multiple energy levels, and the ability to program initial and
subsequent shock energies, allow users to set the
M Series to either a non-progressive or progressive
sequence of shocks.
The M Series supports the use of progressive shock
sequences to provide an energy reserve, allowing the
delivery of a higher energy shock if a lower energy shock
fails to terminate the arrhythmia. A sequence of 120J
Biphasic, 150J Biphasic and 200J Biphasic would most
closely approximate the current AHA recommended
escalating energy sequence of 200J, 300J, and 360J for
defibrillator.
adult defibrillation using a monophasic
When an M Series device is equipped with the Biphasic
Option, all Energy Displays shown in Section 3, Section 4,
and Section 5 (for Manual Defibrillation, Advisory
Defibrillation and Automated Defibrillation) of this M Series
Operators Guide are modified to add the word BIPHASIC
to the energy display as shown below.
The M Series is capable of delivering energy up to 200
Joules with external paddles or Multi-Function Pads. The
initial default energy setting for the M Series Biphasic option
is 120J with external paddles or Multi-Function Pads. The
energy settings available with the M Series Bi-Phasic device
are 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 50, 75, 100, 120,
150 and 200 Joules. Energy settings are selected by using
the controls located on the Sternum Paddle or on the front
panel of the unit.
Upon power-up M Series units equipped with the Rectilinear
Biphasic Waveform Defibrillator Option automatically default
to the 120 Joule setting. In units with automatic progressive
energy selection enabled, Shock No. 1 is set at 120J; Shock
No. 2 is set at 150J and Shock No. 3 is set at 200J. These
are the default energy settings. They may be modified
following the instructions in the M Series Configuration
Guide.
Charge Time
Charge time: < 6 seconds with a new fully charged battery
(first 15 charges to 200 Joules). Depleted batteries will
result in a longer Defibrillator charge time.
All other operational aspects of the M Series Rectilinear
Biphasic Waveform Defibrillator are identical to those
described in the M Series Operators Guide.
Recorder Printer Annotations
In addition to the information normally printed on the
M Series recorder and the M Series Summary Reports
described in Section 2, units equipped with the Biphasic
Option will also print Defibrillation Impedance (DEFIB
IMPEDANCE), and Delivered Current (PATIENT
CURRENT). This information will be included in the
Summary Report for each defibrillation shock.
NAME
BIPHASIC DEFIBRILLATION
ECG LEAD
ECG SIZE
JOULES SELECTED
JOULES DELIVERED
PATIENT CURRE NT
DEFIB IMPEDANCE
PADS
3.0
30
34
34 A
71 Ohms
PRE SHOCK 15:18:45 10 MAY 93
POST SHOCK 15:18:45
The maximum energy available from the M Series with
Rectilinear Biphasic Waveform Option is 200 Joules. If the
operator attempts to increase the energy level above 200
Joules the error message 200 Joules Max Biphasic will be
displayed.
9650-0209-01 Biphasic- 2
RECTILINEAR BIPHASIC WAVEFORM
Energy Delivery Test
The energy delivery test for the Biphasic Option is
performed at 30 J according to the instructions contained in
Section 9 of the M Series Operators Guide.
When performing the energy delivery test at 30J the
recorder strip should resemble that shown below.
12:46:30 02-SEP-99 PAD SIZE 1.0 HR = 30 30 JOULES TEST OK TEST_CUR = 11A DEFIB_IMPED = 1
Rectilinear Biphasic Waveform
Defibrillator Option Information
The Biphasic Option has been designed to produce a
Rectilinear Biphasic Waveform whose shape remains
essentially constant from patient to patient by the device.
Current
(I Patient)
BIPHASIC DEFIBRILLATION PULSE
120 JOULES INTO 50 OHM LOAD
Duration (msec)
The Rectilinear Biphasic Waveform consists of a 6
millisecond, essentially constant current first phase followed
by a 4 millisecond, truncated exponential second phase.
The first and second phases of the defibrillation waveform
are of opposite polarity and their amplitudes vary based on
the user selected therapeutic energy level. The initial
amplitude of this waveform's second phase is approximately
equal to the first phase's final amplitude. This waveform has
an integrated patient impedance measurement sensing
pulse at the beginning of the waveform. The positive and
negative phases are separated by 100 µsec. The shape of
the waveforms first phase is controlled by electronics and
software which compensate for different transthoracic
impedances to maintain an essentially constant current
throughout the first phase.
When the highest energy setting is selected and patient
impedance exceeds 85 ohms, the first phase of the
waveform will droop. All other waveform parameters (phase
duration, inter-phase delay and integrated impedance
measurement sensing pulse) remain the same. The
following Rectilinear Biphasic Waveform is produced when
the M Series with Biphasic option is discharged into a 50Ω
load at the default energy setting of 120 Joules. The vertical
axis is in amperes; the horizontal axis is in milliseconds.
(For more detailed information regarding the parameters of
the Rectilinear Biphasic Waveform when discharged into
25Ω, 50Ω, and 100Ω loads at a maximum energy setting of
200 Joules refer to the Specification section of this
Operators Insert.
9650-0209-01 Biphasic - 3
OPTION INSERT
Clinical Trials Results for the M Series Biphasic Waveform:
The Efficacy of ZOLLs Rectilinear Biphasic Waveform has
been clinically verified during various studies for
defibrillation of Ventricular Fibrillation (VF) / Ventricular
Tachycardia (VT) and for synchronized cardioversion of
Atrial Fibrillation (AF). Feasibility studies were performed
initially for defibrillation of VF/VT (n=20) and synchronized
cardioversion of AF (n=21) on two separate groups of
patients to ensure waveform safety and energy selection.
Subsequently two separate, multi-center, randomized
clinical trials were performed to verify the waveforms
efficacy. Descriptions of these studies are provided below.
All studies were performed using ZOLL defibrillation
systems consisting of ZOLL defibrillators, the ZOLL
Rectilinear Biphasic Waveform and ZOLL Multi-Function
Pads.
A) Randomized Multi-Center Clinical Trial for
Defibrillation of Ventricular Fibrillation (VF) and
Ventricular Tachycardia (VT):
Overview: The defibrillation efficacy of ZOLLs Rectilinear
Biphasic Waveform was compared to a monophasic
damped sine waveform in a prospective, randomized, multicenter study of patients undergoing ventricular defibrillation
for VF/VT during electro-physiological studies, ICD implants
and tests. A total of 194 patients were enrolled in the study.
Ten (10) patients who did not satisfy all protocol criteria
were excluded from the analysis.
Objectives: The primary goal of this study was to compare
the first shock efficacy of the 120J Rectilinear Biphasic
Waveform with a 200J monophasic waveform. The
secondary goal was to compare all shock (three consecutive
120, 150, 170J) efficacy of the Rectilinear Biphasic
Waveform with that of a monophasic waveform (three
consecutive 200, 300, 360J). A significance level of p=0.05
or less was considered statistically significant using
Fischers Exact test. Also, differences between the two
waveforms were considered statistically significant when the
customary 95% or AHA recommended 90%* confidence
interval between the two waveforms was greater than 0%.
Results: The study population of 184 patients had a mean
14 years. 143 patients were males. 98 patients
age of 63
were in the biphasic group (ventricular fibrillation/flutter,
n=80, ventricular tachycardia, n=18) and 86 patients were in
the monophasic group (ventricular fibrillation/flutter, n=76,
ventricular tachycardia, n=10). There were no adverse
events or injuries related to the study.
The first shock, first induction efficacy of biphasic shocks at
120J was 99% versus 93% for monophasic shocks at 200J
(p=0.0517, 95% confidence interval of the difference of
---2.7% to 16.5% and 90% confidence interval of the
difference of ---1.01% to 15.3%).
±
Monophasic Biphasic
1st Shock Efficacy 93% 99%
p-value 0.0517
95% Confidence. Interval -2.7% to 16.5%
90% Confidence Interval -1.01% to 15.3%
Successful defibrillation with rectilinear biphasic shocks was
achieved with 58% less delivered current than with
monophasic shocks (14 ±1 vs. 33 ±7 A, p=0.0001).
The difference in efficacy between the rectilinear biphasic
and the monophasic shocks was greater in patients with
high transthoracic impedance (greater than 90Ω). The first
shock, first induction efficacy of biphasic shocks was 100%
versus 63% for monophasic shocks for patients with high
impedance (p=0.02, 95% confidence interval of the
difference of ---0.021% to 0.759% and 90% confidence
interval of the difference of 0.037% to 0.706%).
Monophasic Biphasic
1st Shock Efficacy (High
Impedance Patients)
p-value 0.02
95% Confidence. Interval -0.021% to 0.759%
90% Confidence Interval 0.037% to 0.706%
A single patient required a second biphasic shock at 150J to
achieve 100% efficacy versus six patients for whom shocks
of up to 360J were required for 100% total defibrillation
efficacy.
Conclusion: The data demonstrate the equivalent efficacy
of low energy rectilinear biphasic shocks compared to
standard high energy monophasic shocks for transthoracic
defibrillation for all patients at the 95% confidence level.
The data also demonstrate the superior efficacy of low
energy rectilinear biphasic shocks compared to standard
high energy monophasic shocks in patients with high
transthoracic impedance at the 90% confidence level.
There were no unsafe outcomes or adverse events due to
the use of the rectilinear biphasic waveform
* Kerber, R., et. al., AHA Scientific Statement, Circulation,
1997; 95: 1677-1682:
the task force suggests that to demonstrate superiority
of an alternative waveform over standard waveforms, the
upper boundary of the 90% confidence interval of the
difference between standard and alternative waveforms
must be < 0% (i.e., alternative is greater than standard).
63% 100%
.
9650-0209-01 Biphasic- 4
RECTILINEAR BIPHASIC WAVEFORM
B). Randomized Multi-Center Clinical trial for
Cardioversion of Atrial Fibrillation (AF).
Overview: The defibrillation efficacy of ZOLLs Rectilinear
Biphasic Waveform was compared to a monophasic
damped sine waveform in a prospective randomized multicenter study of patients undergoing cardioversion of their
atrial fibrillation. A total of 173 patients entered the study.
Seven (7) patients who did not satisfy all protocol criteria
were excluded from the analysis. ZOLL disposable gel
electrodes with surface areas of 78 cm
2
(posterior) were used exclusively for the study.
cm
Objective: The primary goal of the study was to compare
the total efficacy of four consecutive rectilinear biphasic
shocks (70J, 120J, 150J, 170J) with four consecutive
monophasic shocks (100J, 200J, 300J, 360J). The
significance of the multiple shocks efficacy was tested
statistically via two procedures, the Mantel-Haenszel
statistic and the log-rank test, significance level of p=0.05 or
less was considered statistically significant. The data are
completely analogous to the comparison of two survival
curves using a life-table approach where shock number
plays the role of time.
The secondary goal was to compare the first shock success
of rectilinear biphasic and monophasic waveforms. A
significance level of p=0.05 or
statistically significant using Fisher Exact tests. Also,
differences between the two waveforms were considered
statistically significant when the 95% confidence interval
between the two waveforms was greater than 0%.
Results: The study population of 165 patients had a mean
12 years with 116 male patients.
age of 66
The total efficacy of consecutive rectilinear biphasic shocks
was significantly greater than that of monophasic shocks.
The following table displays the Kaplan-Meier (product-limit)
survival curves for each of the two waveforms. As all
patients begin in the failure mode, the estimated life-table
probabilities refer to the chance of still being in failure after
the k
±
th
shock (k=1,2,3,4):
2
(anterior) and 113
less was considered
Kaplan-Meier Estimate for the
Shock #
Probability of Shock Failure
Biphasic Monophasic
0 1.000 1.000
1 0.318 0.792
2 0.147 0.558
3 0.091 0.324
4 0.057 0.208
As can be seen from the table, the Biphasic experience is
superior over the entire course of shocks delivered. The one
degree of freedom chi-square statistic for the MantelHaenszel test is 30.39 (p<0.0001). Similarly, the log-rank
test, also a one degree of freedom chi-square statistic, is
30.38 (p<0.0001). The residual number of patients not
successfully treated after four shocks is 5.7% for biphasic
compared to 20.8% for monophasic.
There was a significant difference between the first shock
efficacy of biphasic shocks at 70J of 68% and that of
monophasic shocks at 100J of 21% (p=0.0001, 95%
confidence interval of the difference of 34.1% to 60.7%).
Successful cardioversion with rectilinear biphasic shocks
was achieved with 48% less delivered current than with
1 vs. 21±4 A, p<0.0001).
monophasic shocks (11
One half of the patients who failed cardioversion after four
consecutive escalating monophasic shocks were
subsequently successfully cardioverted using a biphasic
shock at 170J. No patient was successfully cardioverted
using a 360J monophasic shock after the patient had failed
cardioversion with biphasic shocks.
Conclusion: The data demonstrate the superior efficacy of
low energy rectilinear biphasic shocks compared to high
energy monophasic shocks for transthoracic cardioversion
of atrial fibrillation. There were no unsafe outcomes or
adverse events due to the use of Rectilinear Biphasic
Waveform.
±
Synchronized Cardioversion of Atrial
Fibrillation
Cardioversion of Atrial Fibrillation (AF) and overall clinical
effectiveness is enhanced by proper pad placement. Clinical
studies (refer to above) of the M Series Biphasic
Defibrillator Waveform Option demonstrated that high
conversion rates are achieved when defibrillation pads are
placed as shown in the diagram below.
Recommended Anterior/Posterior Placement
Back/
Posterior
Place the Front (Apex) pad on the third intercostal space,
mid clavicular line on the right anterior chest. The
Back/Posterior Pad should be placed in the standard
posterior position as shown.
Front/
Apex
Defibrillation and Cardioversion
Performance
Caution:
Defibrillator Waveform Option are based upon the use of
ZOLL Multi-Function Pads. The combination of waveform,
electrode properties and gel characteristics is essential to
achieving efficacy results similar to those described above.
For synchronized cardioversion of Atrial Fibrillation, the
combination of waveform, electrode properties, gel
characteristics and pad placement is essential to achieving
efficacy results similar to those above.
WARNING: Unnecessary skin damage can result from
incorrect application or use of a defibrillation pad other than
the type recommended.
The clinical results for the ZOLL Biphasic
9650-0209-01 Biphasic - 5
OPTION INSERT
Additional Messages and TroubleShooting
The following chart lists the messages that may appear on the M Series unit relating to the Biphasic Option, why the
message appeared, and the action(s) to take.
The operator should become thoroughly familiar with this information before using the device.
Message Possible Cause(s) Recommended Action(s)
200 J MAX BIPHASIC Appears when trying to select an energy higher No higher energy is available.
than 200 Joules. Use 200J setting.
BRIDGE TEST FAILED Biphasic module not operating properly while Try charging again. Attempt to
charging. clear the message by turning the
Selector Switch to OFF then back
to the desired operating mode. If
Fault persists contact ZOLL
Technical Service Department.
BRIDGE SHORT Current higher than expected was detected. Ensure pads/paddles are used
properly. Attempt to clear the
message by turning the Selector
Switch to OFF then back to the
desired operating mode. If Fault
persists contact ZOLL Technical
Service Department.
Additional Specifications and Changes
General
Refer to M Series Operators Guide for ALL Specifications except the following:
Waveform: Rectilinear Biphasic
Energy Settings: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 50, 75, 100, 120, 150, 200
Charge Time: Less than 6 seconds with a new fully charged battery
(first 15 charges at 200J)
Messages: 200 J MAX BIPHASIC, BRIDGE TEST FAILED, BRIDGE SHORT
Operating Time: For a new, fully charged battery pack at 20°C: 40 defibrillator
discharges at maximum energy (200J), or 2.75 hours minimum of
continuous ECG monitoring, or 2.25 hours of continuous ECG
monitoring/pacing at 60 mA, 80 beats/min.
9650-0209-01 Biphasic- 6
RECTILINEAR BIPHASIC WAVEFORM
The following table shows the Rectilinear Biphasic waveforms characteristics when discharged into 25Ω, 50Ω, and 100Ω
loads at a maximum energy setting of 200 Joules.
I
01 = First Phase
MAX
Maximum Initial
Current
I
01 = First Phase
AVG
Average Current
Discharged into 25ΩΩΩΩ Load Discharged into 50ΩΩΩΩ Load Discharged into 100ΩΩΩΩ Load
30 A 26 A 21 A
27 A 23 A 16 A
TD 01 = First Phase
Duration
T
= Interphase
INTD
duration between
first and second
phases.
I
02 = Second Phase
MAX
Maximum Initial
Current
I
02 = Second Phase
AVG
Average Current
TD 02 = Second Phase
Duration
6 ms 6 ms 6 ms
100 µs 100 µs 100 µs
26 A 21 A 14 A
15 A 15 A 12 A
4 ms 4 ms 4 ms
9650-0209-01 Biphasic - 7
Loading...