AutoPulse
Encyclopedia
The AutoPulse is an automated, portable, battery-powered cardiopulmonary resuscitation
device created by Revivant and subsequently purchased and currently manufactured by ZOLL Medical Corporation. It is a chest compression device composed of a constricting band and half backboard that is intended to be used as an adjunct to CPR during advanced cardiac life support
by professional health care providers. The AutoPulse uses a distributing band to deliver the chest compressions. In literature it is also known as LDB-CPR (Load Distributing Band-CPR).
The AutoPulse measures chest size and resistance before it delivers the unique combination of thoracic and cardiac chest compressions. The compression depth and force varies per patient. The chest displacement equals a 20% reduction in the anterior-posterior chest depth. The physiological duty cycle is 50%, and it runs in a 30:2 or continuous compression mode, which is user-selectable.
, and the motors that operate the LifeBand. The LifeBand is an adjustable strap that covers the entire rib cage. When the patient (who must be disrobed) is strapped in and the start button is pressed, the LifeBand pulls tight around the chest, determines the patient's chest size and resistance, and proceeds to rhythmically constrict the entire rib cage, pumping the heart at a rate of 80 compressions per minute. The LifeBand can be placed over defibrillation
pads but must be temporarily loosened to use standard paddle defibrillators and repositioned after the shock has been delivered. The LifeBand is disposable, and designed to be used on a single patient for sanitary reasons.
Several animal studies have shown that automated CPR machines are more effective at providing circulatory support than manual CPR. One study showed that use of the AutoPulse produced blood flow to the heart and brain that was comparable to pre-arrest levels. In another study, an adapted AutoPulse was shown to be highly effective in support of cardiac arrest in animals, whereas manual CPR was tenuous in its effectiveness. Pigs were used in the study, and were left in cardiac arrest for eight minutes to simulate average ambulance response time. 73% of the pigs that were put into the AutoPulse were revived, and 88% of the surviving pigs showed no neurological damage. None of the pigs that received manual CPR survived.
The device has shown less promise with human research. Although some studies showed improved coronary perfusion pressure and more spontaneous return of circulation with the AutoPulse, one large, multi-centered, randomized clinical trial was canceled early by the Institutional Review Board
(IRB) when it was determined that patients who received manual CPR were more likely to walk out of the hospital, suggesting that enthusiasm for the device "is premature, given that the effectiveness of the device likely depends on still-to-be-defined factors independent of the mechanical capabilities of the device."
The 2005 American Heart Association
Guidelines for Cardiopulmonary Resuscitation
give load-distributing band CPR (LDB-CPR) a Class IIb recommendation.
and was placed on the AutoPulse, which performed almost 20,000 compressions, keeping his heart and lungs functioning while a medical team worked on him. After almost 3 and a half hours, his pulse returned.
CNN's Anderson Cooper 360° featured a story on April 6, 2010, about the Firehouse Subs Public Safety Foundation, in which Firehouse Subs founders Chris and Robin Sorensen met with Francisco Tuttle, a father who was saved by the Mt. Pleasant, SC, Fire Department using a ZOLL AutoPulse, which the Foundation donated to the department last year.
ABC World News Tonight on May 19, 2005, did a story on automated CPR machines, and profiled the story of Caralee Welch, who survived thirty minutes of cardiac arrest during which the AutoPulse was used. She had a heart attack in front of a theatre, but even after a half-hour of no heartbeat, with AutoPulse's help she ultimately recovered with no apparent brain damage.
Cardiopulmonary resuscitation
Cardiopulmonary resuscitation is an emergency procedure which is performed in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person in cardiac arrest. It is indicated in those who are unresponsive...
device created by Revivant and subsequently purchased and currently manufactured by ZOLL Medical Corporation. It is a chest compression device composed of a constricting band and half backboard that is intended to be used as an adjunct to CPR during advanced cardiac life support
Advanced cardiac life support
Advanced cardiac life support or Advanced Cardiovascular Life Support refers to a set of clinical interventions for the urgent treatment of cardiac arrest and other life threatening medical emergencies, as well as the knowledge and skills to deploy those interventions.Extensive medical knowledge...
by professional health care providers. The AutoPulse uses a distributing band to deliver the chest compressions. In literature it is also known as LDB-CPR (Load Distributing Band-CPR).
The AutoPulse measures chest size and resistance before it delivers the unique combination of thoracic and cardiac chest compressions. The compression depth and force varies per patient. The chest displacement equals a 20% reduction in the anterior-posterior chest depth. The physiological duty cycle is 50%, and it runs in a 30:2 or continuous compression mode, which is user-selectable.
Device operation
The patient's head, shoulders and upper back lay upon the base unit, with the controls for the AutoPulse beside the patient's left ear. It can be augmented for cervical spinal support. The unit contains the control computer, the rechargeable batteryBattery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
, and the motors that operate the LifeBand. The LifeBand is an adjustable strap that covers the entire rib cage. When the patient (who must be disrobed) is strapped in and the start button is pressed, the LifeBand pulls tight around the chest, determines the patient's chest size and resistance, and proceeds to rhythmically constrict the entire rib cage, pumping the heart at a rate of 80 compressions per minute. The LifeBand can be placed over defibrillation
Defibrillation
Defibrillation is a common treatment for life-threatening cardiac arrhythmias, ventricular fibrillation and pulseless ventricular tachycardia. Defibrillation consists of delivering a therapeutic dose of electrical energy to the affected heart with a device called a defibrillator...
pads but must be temporarily loosened to use standard paddle defibrillators and repositioned after the shock has been delivered. The LifeBand is disposable, and designed to be used on a single patient for sanitary reasons.
Mechanism of CPR blood flow
The load-distributing band system, employing thoracic compressions, produces higher blood flow compared to CPR consisting of sternal compressions only. The potential to produce blood flow for a sudden cardiac arrest victim is in large part determined by the peak power of the compression. Factors determining the power of the compression are the force of the compression, the depth of the compression, and the duration that the compression is held at maximum depth.Studies and clinical trials
The gold standard for resuscitation research is survival to hospital discharge. Although common sense suggests that short-term and intermediate outcomes like return of spontaneous circulation (ROSC) or survival to hospital admission are promising, experienced scientists know that anything less than a neurologically intact survivor walking out of the hospital is ultimately irrelevant.Several animal studies have shown that automated CPR machines are more effective at providing circulatory support than manual CPR. One study showed that use of the AutoPulse produced blood flow to the heart and brain that was comparable to pre-arrest levels. In another study, an adapted AutoPulse was shown to be highly effective in support of cardiac arrest in animals, whereas manual CPR was tenuous in its effectiveness. Pigs were used in the study, and were left in cardiac arrest for eight minutes to simulate average ambulance response time. 73% of the pigs that were put into the AutoPulse were revived, and 88% of the surviving pigs showed no neurological damage. None of the pigs that received manual CPR survived.
The device has shown less promise with human research. Although some studies showed improved coronary perfusion pressure and more spontaneous return of circulation with the AutoPulse, one large, multi-centered, randomized clinical trial was canceled early by the Institutional Review Board
Institutional review board
An institutional review board , also known as an independent ethics committee or ethical review board , is a committee that has been formally designated to approve, monitor, and review biomedical and behavioral research involving humans with the aim to protect the rights and welfare of the...
(IRB) when it was determined that patients who received manual CPR were more likely to walk out of the hospital, suggesting that enthusiasm for the device "is premature, given that the effectiveness of the device likely depends on still-to-be-defined factors independent of the mechanical capabilities of the device."
The 2005 American Heart Association
American Heart Association
The American Heart Association is a non-profit organization in the United States that fosters appropriate cardiac care in an effort to reduce disability and deaths caused by cardiovascular disease and stroke. It is headquartered in Dallas, Texas...
Guidelines for Cardiopulmonary Resuscitation
Cardiopulmonary resuscitation
Cardiopulmonary resuscitation is an emergency procedure which is performed in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person in cardiac arrest. It is indicated in those who are unresponsive...
give load-distributing band CPR (LDB-CPR) a Class IIb recommendation.
| Class I | Definitely recommended. Supported by excellent evidence. |
| Class IIa | Acceptable and useful. Good to very good evidence provides support. |
| Class IIb | Acceptable and useful. Fair to good evidence provides support. |
| Class III | Unacceptable, no documented benefit, may be harmful. |
In the news
Mirror, a U.K. news website, on January 14, 2011, reports on Arun Bhasin, who 'came back from the dead' after 3 and a half hours. He was found unconscious and brought into Croydon University Hospital. He suffered a cardiac arrestCardiac arrest
Cardiac arrest, is the cessation of normal circulation of the blood due to failure of the heart to contract effectively...
and was placed on the AutoPulse, which performed almost 20,000 compressions, keeping his heart and lungs functioning while a medical team worked on him. After almost 3 and a half hours, his pulse returned.
CNN's Anderson Cooper 360° featured a story on April 6, 2010, about the Firehouse Subs Public Safety Foundation, in which Firehouse Subs founders Chris and Robin Sorensen met with Francisco Tuttle, a father who was saved by the Mt. Pleasant, SC, Fire Department using a ZOLL AutoPulse, which the Foundation donated to the department last year.
ABC World News Tonight on May 19, 2005, did a story on automated CPR machines, and profiled the story of Caralee Welch, who survived thirty minutes of cardiac arrest during which the AutoPulse was used. She had a heart attack in front of a theatre, but even after a half-hour of no heartbeat, with AutoPulse's help she ultimately recovered with no apparent brain damage.
Miscellaneous
On March 8, 2010 a Fire Department Captain put himself in the AutoPulse device and the device was turned on while he was giving an introduction of the device to a group of children. After providing two complete compressions, the device was turned off and the Fire Captain was released. A medical evaluation is pending.External links
- AutoPulse Official Website
- CPR Machine Proves More Effective Than Paramedics from ABCNews.com (It does not mention AutoPulse by name, but her story is also profiled on the AutoPulse website.)
- LUCAS An alternative method for providing mechanical chest compressions.