TORONTO -- Every emergency department doctor who treats children has probably had conversations that started with: "I'm pretty sure he's fine, but..." or "I know I shouldn't be here, but..."

A tally done by the Children's Hospital of Eastern Ontario found that roughly 45 per cent of the 72,500 kids who were seen in the emergency room in the last fiscal year had health problems that were of "low acuity." That means they were not urgent or severe.

Many of those children could have -- and should have -- been cared for by family doctors or at walk-in clinics, says Dr. Ken Farion, an emergency medicine physician.

But anxious parents often flood hospital ERs wanting reassurances that their children are really OK and are going to be fine.

The Ottawa-based hospital is trying to educate parents on the appropriate use of the emergency department, so all children get timely care and the sickest get the urgent medical resources they need.

"Where five or six years ago we would have seen about a third of our patients would have been lower acuity, we're now seeing 45 per cent," Farion says.

"We need families to make a different choice to protect this resource for the children who clearly need to be here."

CHEO is launching an effort to help parents make decisions that are sometimes not at all clear cut. After young patients get treated, the medical staff will discuss with their parents whether the illness required emergency department care. They will also give parents a brochure designed to help make the right choice next time.

It includes some guidelines:

-- Fever in a normally healthy child who has been vaccinated and who appears playful when the temperature is brought down by drugs can be seen by a family doctor. Fever in an infant (under three months) or in a child who appears very sleepy and hard to wake should lead to the ER.

-- Minor head injuries with no loss of consciousness, confusion or vomiting can be seen by a family doctor or at a walk-in clinic. Head injuries involving loss of consciousness, confusion and repeated vomiting, or which require stitches, should be seen in the emergency department.

Still, kids don't come with instruction manuals and when in doubt, many parents will err on the side of caution.

Dr. Stephen Porter understands how it happens. A child wakes up in the middle of the night with chills and the thermometer shows parents "a number that they've never seen before in their lives."

The judgment can be hard to make in the moment, says Porter, head of emergency medicine at Toronto's Hospital for Sick Children.

He says about between a quarter and a third of the children Sick Kids sees in the emergency department have ailments that rate as non-urgent or less-urgent. If hospital staff ask parents why they didn't go somewhere else first, Porter says the reply is often that the ER was their only option or their best option.

Farion says some families don't have a family doctor, or go to the emergency department because their doctor doesn't have arrangements in place for care outside of regular office hours. (Sometimes those doctors actually do, but parents may be unaware of the option.)

In some cases, however, children's hospitals are the victims of their own success.

"Families are going for what they perceive to be the best care right off the bat," Farion says.

"But we can't continue to provide that high level of care for the children who really need a tertiary care centre if we're also being asked to provide care for all children for all things."

The CHEO "Choosing Wisely" program suggests parents who aren't sure whether their child needs emergency department care should spend a few minutes online, checking reputable websites like those of the Canadian Pediatric Society, their local children's hospital or www.aboutkidshealth.ca, a Sick Kids site.

"What we don't want is for you to just Google blindly 'fever' and 'rash.' Well of course you're going to get at some point the worst case scenario," Farion says.

"We just are trying to inform families and give them the tools they need to manage this in a calm way and an informed way."