People practice CPR compressions on a mannequin at San Francisco City Hall on June 1, 2011 in San Francisco, California. Photo: Photo by Justin Sullivan/Getty Images For untrained bystanders who have to perform CPR after seeing an adult collapse, the professional advice just got a little murkier.
For years, people were taught to give chest compressions followed by mouth-to-mouth ventilations.
Then, in 2010, the International Liaison Committee on Resuscitation issued new guidelines in the U.S. and Canada recommending that untrained bystanders skip the mouth-to-mouth “rescue breathing” if they see an adult collapse and instead focus on performing rapid chest compressions.
Now, a commentary published in Canada’s leading medical journal suggests these CPR guidelines are flawed. The concern? “Rescue breathing” involves two manoeuvres: tilting the head and chin back, and blowing into the mouth. The head-tilt, chin-lift component is beneficial on its own as it helps keep the airway open and unblocked and allows passive air in.
The “wholesale elimination” of this mouth-to-mouth ventilation from the new adult CPR protocol for untrained lay people “may be misguided”, Queen’s University anesthesiologist Dr. Anthony Ho and colleagues argue in this week’s edition of the Canadian Medical Association Journal.
Other experts say the article will create unnecessary confusion for untrained rescuers.
What’s the issue?
The latest guidelines recommend chest-compression-only CPR by untrained bystanders in adults who have an out-of-hospital cardiac arrest.
Ho, of the department of anesthesiology and perioperative medicine at Queen’s University and Kingston General Hospital, said he wasn’t comfortable when the guidelines were changed. “I understood why they took out the mouth-to-mouth breathing part by lay people, mainly because it delays initiation of chest compressions,” Ho said. It’s also often not done right.
Studies found that stopping to blow into a person’s mouth takes precious seconds away from the chest compressions that keep blood circulating to the heart and brain.
As well, many people are reluctant to perform CPR for fear of contracting an infectious disease — even though the risk of infection is remote.
But scrapping the head-tilt, chin-lift “was like throwing out the baby with the bath water,” Ho said.
The manoeuvre helps maintain airway “patency” or openness and can still deliver air into the chest, Ho said.
It’s easier to learn and perform in a crisis than mouth-to-mouth, and easy to perform if another rescuer is present (one person could keep the chin tilted back with one hand and call 911 with the other, while the other rescuer performs uninterrupted chest compressions.)
“When you push the chest down, you’re exhaling; when you let the chest recoil, air goes in. But that’s only if the airway is unobstructed.”
The head-tilt, chin-lift may help buy more time “that the patient desperately needs,” Ho said.
A man opens the airway on a mannequin while learning CPR on the steps of San Francisco city hall following a press conference celebrating the 50th anniversary of lifesaving by using CPR on June 1, 2010. (Photo by Justin Sullivan/Getty Images)
How do you do it?
“It’s basically pulling the chin upwards, and backwards,” Ho said. The tongue is lifted up and air can move in.
“As you do that, the head will tilt to some extent as well. We do that on a daily basis as anesthesiologists.”
How successful is chest-compression-only CPR?
The decision to eliminate rescue breathing from the adult CPR protocol for untrained bystanders was supported by a review of three randomized controlled trials that showed chest-compression only CPR was associated with an improved chance of survival compared with conventional, mouth-to-mouth CPR (14 per cent versus 12 per cent.)
“It’s a small but significant improvement. But it’s still only 14 per cent,” Ho said. “There is much room for improvement, and perhaps we can affect that improvement by making sure airway patency is maintained.”
What about children?
The most recent CPR guidelines state that rescue breathing remains important for children and infants. When children go into cardiac arrest it usually isn’t because of a heart problem, but a respiratory problem. The child may be having an asthmatic attack or allergic reaction causing swelling of the airway, or choking on something swallowed. Under those circumstances, as well as drowning, the child needs oxygen.
What do others say?
Dr. Andrew Travers is co-chair of the basic life support task force for the International Liaison Committee on Resuscitation (ILCOR) and one of the expert co-authors of the most recent CPR guidelines. For trained bystanders, “we always advocate airway manoeuvres and all the other bits and pieces of the chain of survival. But never at the expense of poor chest compressions,” said Travers, an ILCOR delegate for the Heart and Stroke Foundation of Canada.
“So asking an average person who is at home — commonly alone — who has witnessed the arrest or collapse of their spouse, husband or family member to now do two things without sacrificing CPR quality is really pushing it,” Travers said.
If the same person can’t do both, “what do you want me to do? Hold the airway open or do chest compressions? There’s only one of me here.”
“It’s missing a little bit of the focus on, where do untrained bystanders respond to a cardiac arrest? Most of those, 95 per cent, are in a person’s home, not in a public location where there may be multiple responders.”
“What we’re talking about is, in the moment, for people who have never had any (CPR) training, we want you to keep it simple: Push hard, push fast. And that’s predicated on much more science than what that (CMAJ) article is referencing,” Travers said.
More than 20,000 Canadians experience an out-of-hospital cardiac arrest each year. Without CPR and defibrillation, fewer than five per cent of those who have a cardiac arrest outside hospital survive.
skirkey@postmedia.com
No comments:
Post a Comment