A woman pulled from a burning apartment in Ottawa's Greenboro neighbourhood was treated for possible cyanide poisoning, likely from inhaling smoke from burning furniture or other modern materials.
Emergency crews were called to a building on Lorry Greenberg Drive around 3:20 a.m. Firefighters said they found a "slight haze" on the third floor, then tracked its source to a unit where they found heavy smoke and flames.
They rescued a woman in her 50s and administered first aid until paramedics arrived.
Ottawa Paramedic Service spokesperson Marc-Antoine Deschamps said the woman was treated for cardiac arrest and possible cyanide poisoning, which can occur when smoke from burning plastics, glues and hydrocarbon-based products is inhaled.
"A tactical paramedic determined there was a high risk of cyanide poisoning giving the amount of smoke that the patient might have inhaled, so they administered an antidote through an access in the patient's bone marrow," Deschamps said.
Paramedics were able to restart the woman's heart, and she was taken to the hospital in critical condition.
It is the first time Ottawa paramedics have administered hydroxocobalamin, a new cyanide antidote that Deschamps said has fewer side effects than the formula used previously.
The cause of the fire is under investigation.
Other residents who had to evacuate the building during the fire were back in their units by 4:30 a.m., firefighters said.