Researchers at Children's Hospital of Eastern Ontario (CHEO) wanted to find out whether first covering the area with a topical analgesic, or painkilling gel, makes the glue less painful when it's used to seal a cut.
In a study of 221 children, aged three months to 17 years old, a preparation of lidocaine-epinephrine-tetracaine, or LET, was applied to the affected area in half the kids before their lacerations were closed with glue, while the other half got a dummy preparation.
Neither the patients nor the health providers doing the treatment knew whether they got the analgesic gel or the placebo.
"We found that the group that got the medication ... it reduced the amount of pain that the kids reported, on average," said Dr. Stuart Harman, a pediatric emergency medicine specialist at CHEO who led the study.
In fact, 51 per cent of children pre-treated with the analgesic reported feeling no pain from the skin glue —which can cause a nasty burning sensation when it comes into contact with a moist wound — compared to 28 per cent in the placebo group.
"It almost doubled the number of kids who said they felt no pain whatsoever," Harman said Monday from Ottawa.
The researchers used two scales, one employing facial expressions, that are designed for children (or their parents, in the case of very young kids) to indicate severity of pain.
The topical painkiller also improved bleeding control when doctors were closing up the cuts with glue, say the researchers, whose 2011-2012 study was published in Monday's issue of the Canadian Medical Association Journal.
Because the analgesic typically takes about 20 minutes to numb the skin and underlying tissue, some doctors have chosen not to use it because they haven't been sure if it is worth the time, Harman said.
"Some physicians either didn't feel that the skin glue was that painful, especially if they're comparing it to how they remember sutures being painful. Some people just sort of thought, 'Well the skin glue, it might hurt a little bit, but I don't think most kids feel pain with it.'
"Other physicians in their experience felt that they definitely had some kids who were crying afterwards and felt strongly that it did hurt," he said.
"But nobody has any proof one way or another, if it hurts or if the LET would make that much of a difference."
The use of skin adhesive to treat cuts is a common procedure; at CHEO alone, doctors repair about 2,000 cuts a year and the number is increasing, Harman said.
"So across Canada this would add up to probably thousands of kids who could leave the hospital saying they felt no pain during their visit as opposed to kids complaining that they felt at least some pain.
"That's important because it helps us towards making this a standard. It helps all of us to move forward to saying: 'OK, let's make it our policy at this hospital that every child who comes in with a cut will just get this stuff applied."
Harman said skin glue is typically used for cuts five centimetres long or less, in areas without a lot of tension — such as over joints — and has a lot of advantages over sutures.
Not only is it less painful, but it also allows cuts to be repaired faster. Unlike sutures, which usually have to be removed, the hardened glue falls off on its own in about 10 to 21 days.
Using an adhesive is also less traumatic for kids, "because they don't have to see a needle coming at them," he said.
There's been a move in the last 15 years or so to make health providers more aware of how children experience pain and its long-term effects, rather than telling them that they need to "tough it out," for instance.
"Children who experience pain with medical procedures when they're young can grow up to be adults who have more fear and anxiety around medical experiences, " he said.
"And there's some evidence that people who are exposed to pain early in life become more sensitive to pain as they get older."