Source: DGNews  |  Posted 2 years ago

By Deborah Brauser

ORLANDO, Fla -- November 20, 2009 -- A novel intranasal method of quickly
cooling the brain may improve survival for patients in cardiac arrest,
according to a study presented here at the American Heart Association (AHA)
Scientific Sessions 2009.

Results from the Pre-Resuscitation Intra-Nasal Cooling Effectiveness (PRINCE)
trial were presented on November 15 during a Late-Breaking Clinical Trial
session.

“Cooling the brain fast and early is critically important,” said lead
investigator Maaret Castrén, MD Karolinska Institute, Stockholm, Sweden.
“Although body temperature must stay above a certain point, the brain can not
get too cold. In fact, the colder the better.”

Currently, therapeutic hypothermia is recommended after patients resuscitated
from cardiac arrest reach the hospital. However, “many medical professionals
believe that cooling could be more effective if started earlier, ideally at the
time of arrest,” explained Dr. Castrén.

As current methods would not be practical in that setting, the investigators
for this study decided to test rapid initiation of intranasal cooling at the
site of arrest, even before normal circulation was re-established, using a
portable new system “about the size of a backpack,” said Dr. Castrén.

This new method uses a noninvasive nasal catheter, which sprays a rapidly
evaporative coolant liquid into the nasal cavity right beneath the brain. In
addition, the unit uses no refrigeration, no plugs, and no electricity, and the
cooling starts within 10 seconds.

The primary endpoint was the device’s effect on neurologically intact survival
to hospital discharge compared with hospital-based cooling alone. Safety and
feasibility were secondary outcomes.

A total of 182 patients in witnessed cardiac arrest were randomised to either
prehospital cooling, initiated as soon as possible during ongoing
cardiopulmonary resuscitation (CPR, n = 83), or standard care upon hospital
arrival (n = 99).

Results showed that neurologically intact survival was significantly greater at
45.5% for patients treated with the intranasal system (if CPR was started
within 10 minutes or less of witnessed collapse) versus 17.7% for the standard
care group (P = .013).

While this difference was no longer significant if CPR was delayed by more than
10 minutes, Dr. Castrén reported that 75% of the patients did received CPR
within the first 10 minutes.

In the intranasal treatment group, cooling after the arrest significantly
lowered both tympanic (P = .000) and core temperatures (P
= .012) upon arrival at the hospital.

In addition, “the time to the target tympanic temperature of 34 degrees was 3
hours faster for the treatment group and 2 hours faster for the time to target
core temperature,” reported Dr. Castrén.

There were 18 device-related adverse events, nasal discolorations being most
commonly reported. These discolorations resolved spontaneously in all patients
who were successfully resuscitated.

“Early cooling of the brain combined with early CPR favourably affected
outcomes, irrespective of rhythm,” summarised Dr. Castrén. “We believe that
this study demonstrates that making every attempt to initiate both CPR and
intra-arrest cooling as early as possible in the resuscitation process should
be adopted.”

Funding for this study was funded by BeneChill.

Presentation title: Intra-arrest Transnasal Cooling: A Randomized
Prehospital Study. Abstract LBCT-20045