Technology overview

This briefing describes the regulated use of the technology for the indication specified, in the setting described, and with any other specific equipment referred to. It is the responsibility of health care professionals to check the regulatory status of any intended use of the technology in other indications and settings.

About the technology

CE marking

The AutoPulse is a class IIb medical device for which the manufacturer, ZOLL Circulation, received a CE mark in November 2003. The CE mark was renewed in January 2014.

Description

The AutoPulse device is an automated, portable, battery‑powered chest compressor, which provides chest compressions as an adjunct to performing manual CPR. The AutoPulse administers standardised whole chest compressions at a consistent rate of 80±5 compressions per minute. The depth of compression causes a chest displacement equal to a 20% reduction in anterior‑posterior chest depth, calculated for each patient according to their chest size. The combination of these factors leads to a constant blood flow to the vital organs (including brain, heart and lungs) and the periphery. The user can select the pattern of compression by choosing between 3 different modes: 30:2 mode gives 30 compressions followed by 2 ventilation pauses of 1.5 seconds, and 15:2 mode gives 15 compressions followed by 2 ventilation pauses of 1.5 seconds. Alternatively, continuous compressions can be given. The patient should be lying on his or her back during treatment.

The device consists of a LifeBand, a platform, and a power system. The latex‑free LifeBand is a load‑distributing band consisting of a cover plate and 2 Tyvek (polyethylene fabric) bands with a Velcro fastener integrated into a compression pad. The LifeBand is fitted across the patient's bare chest, allowing access to skin of the chest for defibrillation electrodes to be applied. The AutoPulse analyses the patient's size and based on this information the LifeBand automatically adjusts in length to fit the patient's chest and provide compressions to the thoracic area (heart region) of the patient. The AutoPulse can be used in people with a chest circumference measuring 76–130 cm, and a chest width of 25–38 cm.

Compressions are applied uniformly around the circumference of the chest, so that the load is distributed equally and no single area (such as the sternum) receives most of the force. The AutoPulse minimises the potential for patient injury by halting compressions and alerting the rescuer (with a single beep signal, a red light, and a message reading 'realign patient') if the LifeBand is improperly placed or it shifts as a result of an unsecured patient moving during transport.

The platform comprises a back‑stabilising board, the mechanical drive mechanism, control system, the electronics and a user control panel.

The power system comprises either a lithium‑ion (Li‑Ion) or nickel‑metal hydride (NiMH) battery, and the battery charger. The minimum battery run‑time for both of these batteries is 30 minutes. Run‑times greater than this are usually needed, depending on patient size and chest compliance. A low battery audio warning indicates when 5 minutes of active operation remain on a battery. This consists of 4 rapid beeps, followed by 2 beeps every 30 seconds. A low battery sign will also be visible in the user control panel. The battery can be changed during operation but the device must be switched off. The maximum charge time is less than 4.25 hours for the Li‑Ion battery and less than 6.25 hours for the NiMH battery.

According to Resuscitation Council UK (2010) Guidelines, healthcare professionals in the Advanced Life Support algorithm must stop CPR every 2 minutes to check for the heart rhythm and pulsations. For this reason a 10 second pause is needed. The AutoPulse battery can be changed in this 10‑second time slot so that there is a decrease in the hands‑off fraction. If the battery must be changed during compressions, mechanical CPR must be stopped for a short period (less than 10 seconds). It is possible to continue or start manual CPR to further decrease the hands‑off fraction.

A carry sheet is provided for out‑of‑hospital or pre‑hospital use. The carry sheet allows the patient to be moved without the need for additional equipment such as a spine board or a scoop stretcher. The carry sheet is CE‑certified and can be used to carry people weighing up to 250 kg.

A transporter is provided for moving patients inside the hospital. The AutoPulse transporter is a cart that carries the AutoPulse vertically for in‑hospital use. The transporter can be used to carry people weighing up to 136 kg, the maximum weight that the AutoPulse backboard will support.

The AutoPulse platform measures 82.6 cm long by 44.7 cm wide by 7.6 cm in height, with a weight (excluding the battery) of 9.3 kg. The rechargeable Li‑Ion battery weighs 1.3 kg, and the rechargeable NiMH battery weighs 2.3 kg. According to the manufacturer, it should take 20 to 30 seconds to apply the AutoPulse, including the removal of the patient's clothes and the application of defibrillation electrodes.

Intended use

The device is intended to be used as an adjunct to, and not a replacement for manual CPR for adults aged 18 years or older, in cases of clinical death as defined by a lack of spontaneous breathing and pulse. In every non‑traumatic cardiac arrest event, manual CPR should be started immediately according to current guidelines and continued until the AutoPulse is in use. The AutoPulse should not be used in people with traumatic injuries (wounds resulting from sudden physical injury or violence).

The use of the AutoPulse is intended to reduce the impact of rescuer fatigue. It is designed to allow the rescuer to attend to the patient's other needs, such as getting air into the lungs or administering defibrillation and medications to restart the heart, while mechanical chest compressions are ongoing. The AutoPulse can also be used while a patient has treatment for hypothermia.

The AutoPulse is expected to improve the safety of paramedics during transport in an ambulance, because they can remain seated and wearing a safety belt while the AutoPulse delivers compressions. Also, in a catheterisation laboratory, staff radiation exposure is minimised while AutoPulse CPR is ongoing.

Setting and intended user

The AutoPulse can be used both in and out of hospital for non‑traumatic cardiac arrest, by personnel trained in basic or advanced life support techniques. This would include emergency medical technicians, paramedics, nurses, physicians and other people certified to administer CPR.

The AutoPulse allows CPR to be continued while moving a patient (for example to an ambulance or air‑ambulance, and from these into the hospital). It can be used in the catheterisation laboratory during angiography and percutaneous coronary intervention, using slightly modified viewing angles. It can also be used during computed tomography (CT) imaging, trans‑thoracic echography and trans‑oesophageal echography. Although an X‑ray of the thorax is possible while the AutoPulse is in place, imaging would be blurred by the electronic and mechanical components within the AutoPulse platform. Additionally, it is not recommended to perform an X‑ray during the resuscitation of a patient without return of spontaneous circulation.

Current NHS options

NICE is aware of the following CE‑marked device that appears to fulfil a similar function to the AutoPulse:

  • LUCAS: Lund University Cardiopulmonary Assist System (Jolife AB/Physio‑Control Lund, Sweden).

Current guidelines recommend manual CPR which involves applying 100–120 compressions per minute to the sternum to a depth of 5–6 cm. Rescue breaths, in combination with chest compressions, should be done in a 30:2 ratio (30 compressions followed by 2 breaths of no more than 5 seconds). If there is more than 1 rescuer present, 1 should take over CPR from the other every 1–2 minutes to prevent rescuer fatigue (Resuscitation Council UK 2010).

One specialist commentator stated that the European Resuscitation Council and the Resuscitation Council (UK) will publish evidence‑based treatment recommendations on mechanical CPR devices in October 2015. This will be based on a systematic review of published evidence as part of the International Consensus on CPR Science.

Costs and use of the technology

The essential components needed include:

  • the AutoPulse platform (£6289)

  • 3 NiMH batteries, £1266 (£422 each) or 3 Li‑Ion batteries, £1476 (£492 each)

  • multi‑chemistry charger (£1107) which can be used for either type of battery

  • carry sheet for out‑of‑hospital use (£380) or a transporter for in‑hospital use (£226)

  • non‑reusable LifeBands (£239 for a pack of 3).

The total cost for an out‑of‑hospital system with NiMH batteries is £9281 and with Li‑Ion batteries is £9491. For an in‑hospital system the total cost with NiMH batteries is £9127 and with Li‑Ion batteries is £9337.

Alternatively, the rental cost of an AutoPulse device to the NHS is £475 per month (excluding VAT). The rental agreement in the UK is with ZOLL UK Ltd.

The AutoPulse Plus platform is an alternative to the standard AutoPulse platform with the same mechanism, but allowing connection to the defibrillator and synchronisation of electrical shocks (£6375). Additional items are the same and have the same cost for both platforms.

The AutoPulse has no user‑serviceable parts, and does not need regular maintenance. There are no components that need calibration, although users should periodically inspect the AutoPulse to ensure the device's functionality. The Li‑Ion battery should be replaced 3 years after date of manufacture and will not operate after 5 years from that date. The NiMH battery will not operate after 100 full charge/discharge cycles and will need to be replaced.

The AutoPulse has an anticipated lifespan of 7 to 10 years.

Likely place in therapy

The purpose of the AutoPulse is not to replace manual CPR, but to be used as a support to manual CPR. It can provide consistent CPR over long periods of time and would be used to reduce the impact of rescuer fatigue while also allowing the rescuer to attend to other patient needs. The AutoPulse can also be used to maintain CPR when there is a need to move a patient, either to conduct further examinations or to seek more specialist care. The AutoPulse is promoted by the manufacturer only for use in cases where manual CPR would normally be initiated (e.g. non‑traumatic cardiac arrest).

Specialist commentator comments

One specialist commentator noted that for out‑of‑hospital cardiac arrests caused by myocardial infarction, using the AutoPulse could allow lifesaving interventions such as primary angioplasty (percutaneous coronary intervention) to be performed while compressions are maintained.

Another specialist commentator suggested that the ideal situations for prolonged use of the AutoPulse are during thrombolysis of patients with a pulmonary embolism or in cases of profound hypothermia. The commentator remarked that whereas the available literature does not show a significant difference in the effectiveness of the AutoPulse compared with that of manual CPR, mechanical CPR devices (such as the AutoPulse) can provide more consistent chest compressions than manual CPR, and that this could have benefits in pre‑hospital care.

The instructions for use of the AutoPulse device say that it should only be used in adults over 18 years of age. One specialist commentator suggested that the device could be used in people of an 'adult size' who are less than 18 years old, and that body size was a more relevant issue than age. This specialist commentator also disagreed with the manufacturer's recommendation that the AutoPulse should only be used in non‑traumatic cardiac arrest. They suggested that some people who experienced traumatic cardiac arrest may benefit from automated chest compressions, for example people who have a hypoxic aetiology such as hanging, asphyxia and drowning.

One specialist commentator mentioned that trials such as the CIRC trial (Wik et al. 2014) may not be an accurate representation of real‑life pre‑hospital CPR scenarios. During such trials it is common for the people in the control group to have 'excellent manual CPR'. This means that clinicians in the control arm would have additional training in CPR and would be checked for compliance with current CPR protocols. People in control groups therefore often have CPR of a very high standard, whereas in reality there are frequently long 'hands‑off times' and poor chest compression fractions, particularly when there is only a single rescuer.

One commentator remarked that the success of automated devices is dependent on other factors known to be associated with a good outcome, for example early CPR from bystanders at the time of the cardiac arrest. It was their view that CPR fractions in the hospital and pre‑hospital phase are often inadequate, and although the trials quoted had chest compression fractions of over 80%, many observational studies have demonstrated fractions as low as 48%.

A specialist commentator mentioned that there are currently 2 high‑quality randomised controlled trials evaluating the use of the AutoPulse (Hallstrom et al. 2006; Wik et al. 2014), and that these trials are less susceptible to bias than case series and case reports.

Equality considerations

NICE is committed to promoting equality and eliminating unlawful discrimination. We aim to comply fully with all legal obligations to:

  • promote race and disability equality and equality of opportunity between men and women, and

  • eliminate unlawful discrimination on grounds of race, disability, age, sex, gender reassignment, pregnancy and maternity (including women post‑delivery), sexual orientation, and religion or belief, in the way we produce our guidance (these are protected characteristics under the Equality Act 2010).

Risk factors for cardiac arrest include age (incidence increases with advancing age) and sex (men are at higher risk of experiencing sudden cardiac arrest). Age and sex are protected characteristics under the Equality Act (2010).

Patient and carer perspective

The NICE Public Involvement Programme highlighted that particular benefits for people from the AutoPulse device relate to preventing neurological harm and re‑establishing circulation.