Press information

Herausgeber:Hohenstein LaboratoriesGmbH & Co KG

Hohenstein Textile Testing InstituteGmbH & Co KG

Hohenstein Institut für Textilinnovation gGmbH

Hohenstein Academy e.V.

Unternehmenskommunikation & ForschungsmarketingSchloss Hohenstein74357 BönnigheimGERMANYFon +49 (0)7143 271-723Fax +49 (0)7143 271-721

E-Mail: presse@hohenstein.deInternet: www.hohenstein.de

Ihr Ansprechpartner für diesen Text:

Rose-Marie RiedlFon +49 7143 271-723Fax +49 7143 271-721

E-Mail: r.riedl@hohenstein.deInternet: www.hohenstein.de

Sie können den Pressedienst honorarfrei auswerten.Bitte senden Sie uns ein Belegexemplar.

Help for cardiac arrest patients – fast and without electricity

Textile cooling pads in new hypothermia emergency vest protect againstneurological damage

25-Jun-2012 | 408-EN

Textile cooling pads are to be used in future to prevent neurological damage aftersuccessful resuscitation. The system developed by scientists from the HohensteinInstitute in Bönnigheim requires no electric power, making it ideal especially for first aidin case of cardiac arrest.

For what can be done when for example a traveller collapses on a bus, train oraeroplane? Every year, 375,000 people suffer a cardiac arrest in Europe alone. Theheart suddenly starts beating uncontrollably, the pulse becomes irregular. Within afew seconds the patient becomes unconscious and breathing and heartbeat stop. Forthose affected, every second counts from this point on, because the patient's chancesof survival decrease by ten percent with every second that passes until reanimation.Defibrillators have now become mandatory in public buildings and public transport.They use electric shock to restart the heartbeat. For most cardiac arrest patients,however, even successful reanimation is merely a partial success – only a few patientssurvive this life-saving measure without consequential neurological damage. This isdue to parts of the brain possibly sustaining lasting damage caused by the lack ofblood flow and oxygen supply during the period until the ambulance arrives. This oftenresults in the affected becoming invalid.

To avoid this type of brain damage in future, scientists from the faculty of Hygiene,Environment & Medicine at the Hohenstein Institute have developed a new therapymethod for first aiders. In the framework of a research project supported by the stateof Baden-Württemberg for the competition 'Biotechnology and medical technology', thescientists lead by Prof. Dr. Dirk Höfer developed the prototype of a textile cooling vest.The new type of medical product promises improved acute treatment for cardiac arrestby very quickly cooling down the patient's body.

It has been known for a long time that cooling can protect the brain against the dreadedoxygen deficit during a lack of blood flow. Targeted lowering of the temperature insidethe body to 32 °C to 34 °C has been proven to protect the brain against irreparableneurological damage. This simple but extremely effective therapy principle was usedby the Hohenstein scientists. They started by developing water-proof and absolutelyairtight textile hollow fabric – so-called cooling pads. These were equipped withappropriate connection options and integrated into a vest. The cooling pads are

Seite - 2 -

connected to a metal container under vacuum pressure containing a special mineral(zeolite). When an interposed valve is opened, the water in the pads is instantlycooled down to nearly freezing (see info box), very effectively draining body heatfrom the patient's body at the same time. The cooling system based on zeolite/wateradsorption technology has a simple design and allows drastic lowering of the core bodytemperature after occurrence of a cardiac arrest at any time and in any place – withoutelectric power! In future the self-sufficient cooling pads are intended to complementmobile defibrillators (with automated ECG analysis) for use by first aiders withoutmedical knowledge e.g. in public buildings and public transport. For patients withcardiac arrest this means a much better chance of sustaining only minor consequentialdamage.

With this product the Hohenstein researchers have managed to develop a new non-invasive method for surface cooling of the body. That means no surgical procedure isrequired and in contrast to conventional cooling systems it can be used directly at theplace of emergency without any power source. “The cooling pads harbour enormouspotential in the neurological rehabilitation after cardiac arrests”, explains Prof. Dr. DirkHöfer. “In addition to the benefits for the affected individual, every prevented case ofinvalidity is also a great financial advantage for the general public.” Even though theresearchers are looking for an industrial partner for production and sales of the coolingpads for the time being, they are already contemplating other innovative applicationsfor textile cooling and heating processes in medicine.

Zeolite/water adsorption technology

Zeolites are natural silicate minerals. Under vacuum they have the property ofadsorbing polar molecules such as steam. Evaporation enthalpy significantly coolsdown the remaining water within a few minutes. The process of cooling generation canbe activated at any time by opening a valve and continues until the zeolite is saturatedwith steam.

Brain damage from lack of blood flow

A number of harmful reactions are triggered when the brain does not receive enoughoxygen as a result of a circulatory problem (ischaemia). This includes e.g. theformation of free radicals and toxic metabolism products. Targeted lowering of thecore body temperature to 32 °C to 34 °C has been proven to protect the brain againstirreparable neurological damage. In medical terms this form of therapy is referredto as 'therapeutic hypothermia' and it is used as a standard treatment in hospitals inthe form of cooling blankets and cold drip solutions. Outside of intensive care units,however, especially at emergency sites, therapeutic hypothermia has not been applieduntil now. That means that precious time passes between receipt of the emergencymessage until arrival of adequate help at the site of emergency (rescue time in Baden-Württemberg: 10-15 minutes). The early time window directly after occurrence of thecirculatory disturbance is therefore crucial because studies show that tissue damage

Seite - 3 -

is directly proportional to the duration of the lack of oxygen. The earlier heart attackpatients are cooled down, the better therefore their chances of survival and the greaterthe possibility of full recovery.

Ready-made functional sample of a self-sufficient mobile hypothermia emergencyvest with integrated cooling pads.©Hohenstein Institute

Functional principle of zeolite/wateradsorption technology. ©HohensteinInstitute

The new cooling pads consist of a water-proof and vacuum-tight textile hollow fabricand are connected to a metal containerunder vacuum pressure. ©HohensteinInstitute

Seite - 4 -

Infrared heat image of the textile coolingpad. ©Hohenstein Institute

Recording the kinetics of the cooling pad.©Hohenstein Institute