After allegedly killing his housemate, David Charles Edgerley told a nurse "the Queen was going to give him the crown", a court has heard.
Edgerley has pleaded not guilty to murder at a Brisbane Supreme Court trial after Victor Graveson died in September 2017.
The 39-year-old man is accused of dousing Mr Graveson in petrol and setting him alight as the 65-year-old slept at his Alexandra Hills home before holding a door closed to ensure there was no escape.
Edgerley only released the door and fled after he was struck with an object by a friend of Mr Graveson, the court heard.
The court was told veteran nurse Sue Carney assessed Edgerley later that morning at Redland hospital in Brisbane's bayside.
Ms Carney said a woman had picked up Edgerley because he looked distressed by the side of the road and dropped him off at the hospital.
The nurse of more than 40 years' experience said Edgerley smelt of petrol, appeared agitated and "wasn't making much sense".
"He continually told me he couldn't be at the hospital because it was too close to Victor and he also told me he had to go to England because the Queen was going to give him the crown," Ms Carney told the jury on Thursday.
She said Edgerley also claimed he needed "some STD testing done" because "Victor had raped his niece".
Ms Carney said she noticed Edgerley had a left lower arm injury and singed hair "like a chemical burn" on the knuckles of his hand.
Asked if he was in pain, Ms Carney said Edgerley told her "his heart hurt more than his head".
"When I asked him what that was about he said because Victor had raped his niece," she said.
Asked about his injuries, Ms Carney said Edgerley told her he had been attempting to light something and it had fallen over and burnt him.
He also claimed to have been on speed for three days.
Police officers arrived at the hospital room when they heard Edgerley and asked if he had any weapons and he removed a lighter from his jacket, Ms Carney said.
Mr Graveson was taken to hospital in a critical condition with burns to 80 per cent of his body but died three days later.
The trial before Justice Soraya Ryan continues.
