NEW YORK (Reuters Health) - When lifeguards try to resuscitate a drowning victim, they typically perform rescue breaths through a mask placed over the victim's mouth. But a small study suggests that lifeguards may perform better with direct mouth-to-mouth breathing.
Standard CPR for drowning victims involves alternating chest compressions with rescue breathing.
According to international recommendations, lifeguards should use a transparent "pocket" mask, placed over the victim's mouth, when delivering rescue breaths. (Doctors and other health professionals generally use what's called a bag-valve mask, while laypeople trained in CPR learn direct mouth-to-mouth breathing.)
Pocket masks may limit the small risk of transmitting an infection during CPR.
However, there is little evidence that lifeguards are actually more efficient at performing CPR with pocket masks versus mouth-to-mouth. Instead, the recommendation is largely based on expert consensus, according to Dr. Bo Lofgren and colleagues at Aarhus University in Denmark.
For their study, published in the journal Resuscitation, the researchers had 60 trained lifeguards perform CPR on mannequins, using each of three breathing techniques -- mouth-to-mouth, pocket mask and bag-valve mask.
Overall, the study found, the lifeguards performed best with mouth-to-mouth. Their rescue breaths were more effective -- with 91 percent creating a visible chest rise in the mannequin, versus 79 percent when using the pocket mask, and 59 percent with the bag-valve mask.
The lifeguards also took less time between rescue breaths and chest compressions when performing mouth-to-mouth.
This is important, the researchers say, because keeping up chest compressions is crucial to keeping blood and oxygen flowing to the brain and the rest of the body.
Using the equipment does take extra time, Lofgren told Reuters Health in an email. So that, the researcher explained, may "increase the interruption" in chest compressions when one person is performing CPR. (If there are two rescuers, one can keep compressions going while the other performs rescue breaths.)
So should lifeguards be performing mouth-to-mouth in real-life emergencies?
"It is too early to conclude that mouth-to-mouth ventilation should be the preferred ventilation technique," Lofgren said.
Using a mask, the researcher noted, may curb the risk of disease transmission and allow rescuers to give supplemental oxygen.
It's also unclear how widely relevant the findings are -- since, Lofgren's team notes, Danish lifeguards' training may differ from that in other countries.
More importantly, exactly how lifeguards' breathing techniques affect drowning victims' survival odds remains unknown.
Still, the researchers write, this study does "highlight the importance of training to further improve the use of (pocket-mask breathing)."
"This underlines that when equipment is implemented," Lofgren said, "training and re-training on the equipment should be offered."
SOURCE: bit.ly/fDgzl0 Resuscitation, online February 17, 2011.