Five-year old Hal was showing dangerous signs of respiratory distress. His lips were turning blue, his eyelids were drooping and the bedside monitor showed oxygen levels in his blood dropping fast.
His nurse — suspecting a problem with the tracheostomy tube that was helping Hal breathe — snapped into action.
"It looks like you are not doing well," nurse Heather Grace said calmly as Hal moaned. "We are going to do a trach change."
If Hal were in a hospital, a team of caregivers would quickly descend on the 50-pound boy to restore his breathing. But Hal, who requires mechanical breathing assistance, is one of a growing number of children being cared for at home. That means his nurse must act quickly, correctly — and largely alone — to prevent a crisis such as cardiac arrest.
Grace replaces his tube. Hal coughs and opens his eyes. His blood oxygen levels quickly recover.
"There was an obstruction in your trach, Hal," Grace says.
It is a scenario Hal will experience again and again. Some nurses will fail him and other nurses will succeed, but Hal helps all of them learn because he is a robot.
He doesn't walk and he can't wave his arms, but Hal is one of the most advanced human simulators, sometimes known as medical dolls or mannequins, to come to market.