People who suffer cardiac arrest - in which the heart
stops beating - were less likely to die in subsequent years when bystanders
performed cardiopulmonary resuscitation using chest compressions only, a new
study found. That builds on previous research that found no short-term survival
differences in adult victims given compression-only CPR instead of the standard
kind, which includes mouth-to-mouth resuscitation.
A plastic CPR training mannequin is seen at Dinamo stadium in Bucharest (Bogdan Cristel Reuters, REUTERS / July 26, 2011)
And it supports an American Heart Association
recommendation that the simpler form of CPR is appropriate for bystanders, who
may feel so intimidated by the prospect of combining chest compressions with
rescue breathing that they give no aid at all. This study shows "we were
on the right track in 2008," said Dr. Roger White of the Mayo Clinic, who
was on the advisory group that wrote the AHA's statement. The recommendations
don't apply to CPR performed in the hospital, nor in the community by medical
personnel or people who are proficient in rescue breathing. They also apply
only to adult, not pediatric, victims.
Some 383,000 people in the U.S. suffer cardiac arrests
every year, and only about 10 percent survive. The study looked at data from
two randomized trials that were published in the New England Journal of
Medicine in 2010 and covered more than 3,200 adults whose cardiac arrests were
likely due to heart problems rather than trauma, suffocating or drowning.
Dispatchers instructed bystanders via phone to use either the standard or
compression-only form of CPR.
The new study's authors, who were from Seattle, France and
Sweden, were able to follow up on longer-term outcomes for 78 percent of those
participants. The one-year survival rate was about 12 percent for chest
compression alone and about 10 percent for compression plus breathing, said Dr.
Florence Dumas, an author of the study, in an email to Reuters Health. After
adjusting for different factors, mortality in the compression-only group was 9
percent lower than in the standard CPR group. The survival benefit persisted
over five years, according to findings published in the journal Circulation. That
suggests "that potential short-term outcome differences do translate to
meaningful long-term public health benefits," said Dumas.
ALLAYING CONCERNS
In 2008 the AHA said compression-only CPR was an option
for bystanders who aren't trained or who aren't confident in their ability to
perform the compressions combined with rescue breathing. Some people have
worried that collapsed victims of non-cardiac events such as drug overdoses or
a blood clot in the lungs might not get the oxygen they need with the
compression-only approach, he said.
But the study authors wrote that, "importantly, we
did not observe evidence of harm among those for whom oxygenation and
ventilation might in theory be more important" such as non-cardiac causes
or an unwitnessed cardiac arrest. There is likely some oxygen remaining in the
blood when a victim's heart has stopped for a short period of time, and the
compression-only technique can distribute it to vital organs. If a person has
been down for a longer or unknown period of time, it's more likely that they'll
need fresh oxygen through rescue breathing, said White, an anesthesiologist and
cardiac care specialist who was not involved in the new study.
That's why the AHA's recommendations apply when bystanders
actually witness an adult suffering cardiac arrest with no obvious non-cardiac
cause such as drowning. (Kids suffering cardiac arrest need rescue breathing.) "The
vast majority (of events) are likely to be cardiac in origin," said White.
"So proceeding with chest compression is likely to be beneficial in the
vast majority of cases," he said. One limitation of the study was that it
tracked survival only; it couldn't assess patients' level of function or
quality of life. In addition, the original trials the study drew from weren't
designed to track long-term outcomes.
Source: Chicago Tribune
No comments:
Post a Comment