1. Press information
Help for cardiac arrest patients – fast and without electricity
Textile cooling pads in new hypothermia emergency vest protect against
neurological damage
25-Jun-2012 | 408-EN
Textile cooling pads are to be used in future to prevent neurological damage after
successful resuscitation. The system developed by scientists from the Hohenstein
Institute in Bönnigheim requires no electric power, making it ideal especially for first aid
in case of cardiac arrest.
For what can be done when for example a traveller collapses on a bus, train or
aeroplane? Every year, 375,000 people suffer a cardiac arrest in Europe alone. The
heart suddenly starts beating uncontrollably, the pulse becomes irregular. Within a
few seconds the patient becomes unconscious and breathing and heartbeat stop. For
those affected, every second counts from this point on, because the patient's chances
of 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 patients
survive this life-saving measure without consequential neurological damage. This is
due to parts of the brain possibly sustaining lasting damage caused by the lack of
blood flow and oxygen supply during the period until the ambulance arrives. This often
results 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 therapy
method for first aiders. In the framework of a research project supported by the state
of Baden-Württemberg for the competition 'Biotechnology and medical technology', the
scientists 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 arrest
by very quickly cooling down the patient's body.
It has been known for a long time that cooling can protect the brain against the dreaded
oxygen deficit during a lack of blood flow. Targeted lowering of the temperature inside
the body to 32 °C to 34 °C has been proven to protect the brain against irreparable
neurological damage. This simple but extremely effective therapy principle was used
by the Hohenstein scientists. They started by developing water-proof and absolutely
airtight textile hollow fabric – so-called cooling pads. These were equipped with
appropriate connection options and integrated into a vest. The cooling pads are
Herausgeber: Ihr Ansprechpartner für diesen Text:
Hohenstein Laboratories Unternehmenskommunikation & Forschungsmarketing
GmbH & Co KG Schloss Hohenstein Rose-Marie Riedl
74357 Bönnigheim Fon +49 7143 271-723
Hohenstein Textile Testing Institute GERMANY Fax +49 7143 271-721
GmbH & Co KG Fon +49 (0)7143 271-723
Fax +49 (0)7143 271-721 E-Mail: r.riedl@hohenstein.de
Hohenstein Institut für Textilinnovation gGmbH Internet: www.hohenstein.de
E-Mail: presse@hohenstein.de
Hohenstein Academy e.V. Internet: www.hohenstein.de Sie können den Pressedienst honorarfrei auswerten.
Bitte senden Sie uns ein Belegexemplar.

2. 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 instantly
cooled down to nearly freezing (see info box), very effectively draining body heat
from the patient's body at the same time. The cooling system based on zeolite/water
adsorption technology has a simple design and allows drastic lowering of the core body
temperature after occurrence of a cardiac arrest at any time and in any place – without
electric power! In future the self-sufficient cooling pads are intended to complement
mobile defibrillators (with automated ECG analysis) for use by first aiders without
medical knowledge e.g. in public buildings and public transport. For patients with
cardiac arrest this means a much better chance of sustaining only minor consequential
damage.
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 is
required and in contrast to conventional cooling systems it can be used directly at the
place of emergency without any power source. “The cooling pads harbour enormous
potential in the neurological rehabilitation after cardiac arrests”, explains Prof. Dr. Dirk
Höfer. “In addition to the benefits for the affected individual, every prevented case of
invalidity is also a great financial advantage for the general public.” Even though the
researchers are looking for an industrial partner for production and sales of the cooling
pads for the time being, they are already contemplating other innovative applications
for textile cooling and heating processes in medicine.
Zeolite/water adsorption technology
Zeolites are natural silicate minerals. Under vacuum they have the property of
adsorbing polar molecules such as steam. Evaporation enthalpy significantly cools
down the remaining water within a few minutes. The process of cooling generation can
be activated at any time by opening a valve and continues until the zeolite is saturated
with steam.
Brain damage from lack of blood flow
A number of harmful reactions are triggered when the brain does not receive enough
oxygen as a result of a circulatory problem (ischaemia). This includes e.g. the
formation of free radicals and toxic metabolism products. Targeted lowering of the
core body temperature to 32 °C to 34 °C has been proven to protect the brain against
irreparable neurological damage. In medical terms this form of therapy is referred
to as 'therapeutic hypothermia' and it is used as a standard treatment in hospitals in
the form of cooling blankets and cold drip solutions. Outside of intensive care units,
however, especially at emergency sites, therapeutic hypothermia has not been applied
until now. That means that precious time passes between receipt of the emergency
message 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 the
circulatory disturbance is therefore crucial because studies show that tissue damage

3. Seite - 3 -
is directly proportional to the duration of the lack of oxygen. The earlier heart attack
patients are cooled down, the better therefore their chances of survival and the greater
the possibility of full recovery.
Ready-made functional sample of a self-
sufficient mobile hypothermia emergency
vest with integrated cooling pads.
©Hohenstein Institute
Functional principle of zeolite/water
adsorption technology. ©Hohenstein
Institute
The new cooling pads consist of a water-
proof and vacuum-tight textile hollow fabric
and are connected to a metal container
under vacuum pressure. ©Hohenstein
Institute

4. Seite - 4 -
Infrared heat image of the textile cooling
pad. ©Hohenstein Institute
Recording the kinetics of the cooling pad.
©Hohenstein Institute