Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Heart rate may predict survival and brain function in comatose cardiac arrest survivors

20.10.2014

Researchers may have developed a way to potentially assist prognostication in the first 24 hours after out-of-hospital cardiac arrest (OHCA) when patients are still in a coma. Their findings are revealed today at Acute Cardiovascular Care 2014 by Dr Jakob Hartvig Thomsen from Copenhagen, Denmark.

Acute Cardiovascular Care is the annual meeting of the Acute Cardiovascular Care Association (ACCA) of the European Society of Cardiology (ESC) and takes place 18-20 October in Geneva, Switzerland.


This figure shows the 180-day mortality rate by experience of sinus bradycardia during therapeutic hypothermia.

Credit: Jakob Hartvig Thomsen

Dr Thomsen said: "When we talk to relatives and friends immediately after a cardiac arrest we often tell them that we're not able to say much about the prognosis for their Dad, Mom, friend, etc, for the next 3 to 4 days. This is incredibly distressing and loved ones are desperate for more information."

He added: "Therapeutic hypothermia is used in comatose survivors of OHCA to protect them from brain damage. Current recommendations say that prognostication should not be made until 72 hours after hypothermia when patients have returned to normothermia and the sedation has worn off.1 The prognostic tools presently available are not reliable until after this 72 hour period."

Dr Thomsen continued: "During hypothermia some patients lower their heart rate, which is called bradycardia. We hypothesised that this is a normal physiological reaction and that these patients may have less severe brain injury after their arrest and therefore lower mortality."

The study was conducted in the intensive care unit at Copenhagen University Hospital during 2004-2010 and was supported by the EU Interreg IV A programme. It included 234 comatose survivors of OHCA who underwent the hospital's standard 24 hour therapeutic hypothermia protocol. Heart rhythm was measured hourly and sinus bradycardia (defined as less than 50 heart beats per minute) was used to stratify the patients. The primary endpoint was 180 day mortality.

The investigators found that patients who experienced sinus bradycardia during therapeutic hypothermia had a 17% 180 day mortality rate compared to 38% in those with no sinus bradycardia (p<0.001) (figure 1), with a hazard ratio (HR) of 0.38. Sinus bradycardia during therapeutic hypothermia remained an independent predictor of lower 180 day mortality with a HR of 0.51 after adjusting for known confounding factors including sex, age, comorbidity, witnessed arrest and bystander CPR.

Dr Thomsen said: "Patients with sinus bradycardia during therapeutic hypothermia had a 50-60% lower mortality rate at 180 days than those with no sinus bradycardia. We also found that sinus bradycardia was directly associated with a better neurological status 180 days after the arrest."

Few patients are in sinus bradycardia when they arrive at the intensive care unit (a period called the induction phase). However the proportion rises during hypothermia to almost 50%, and then declines during the rewarming phase.

Dr Thomsen said: "We speculated that this proportion of patients who develop sinus bradycardia during hypothermia would have better brain function and a lower mortality rate, and that was what we found. "

He added: "Now when we observe that a patient experiences sinus bradycardia below 50 beats per minute within the first 24 hours we can tell families that their relative may have a chance of recovery."

Dr Thomsen continued: "There is a lot of discussion about defining criteria to identify patients we should stop treating when a vegetative state is inevitable. We shouldn't give up on patients who still have a chance so this is an area in which we need to be very certain. Our findings provide an early marker of patients who may do well. Hopefully in the future, together with other tools, we will be able to differentiate between those with a very good or very poor prognosis so we can prioritise intensive care resources."

He concluded: "We are currently validating our findings by conducting the same analysis in the 950 patients included in the Targeted Temperature Management trial which was conducted in 36 intensive care units."

Jacqueline Partarrieu | Eurek Alert!
Further information:
http://www.escardio.org

More articles from Health and Medicine:

nachricht Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

Metallic nanoparticles will help to determine the percentage of volatile compounds

20.10.2017 | Materials Sciences

Shallow soils promote savannas in South America

20.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>