A member of the public who noticed the knife approached Pura and talked to him.
Pura told the other person he was going to smash his way through the hospital entrance window and into the accident and emergency department waiting room.
He then drove over the kerb and over a roundabout towards the A & E drop-off area followed by the member of the public who continued to speak to Pura, the court heard.
Police were called.
Pura then pointed the knife at the member of the public who backed away.
In an attempt to evade the attending police, Pura reversed his vehicle in the direction of an approaching patrol car.
He then drove into a bollard and the vehicle became wedged against it.
When police smashed the driver's window to gain entry, Pura thrust the knife at a police officer in a continuous stabbing motion which hit his shoulder but caused no injury.
Fearing for their safety police tasered Pura but it had no effect due to the clothing he was wearing. The defendant threw the knife out the window towards the police officer.
Pura had a rope around his neck and he tightened it, causing him to choke. A police officer cut the rope to prevent the defendant from further harming himself.
Police had to taser Pura to remove him from the vehicle before he was taken into custody.
Pura's lawyer Viv Winiata told Judge Paul Mabey QC that his client was now back on his medication and remained in a stable condition.
Mr Winiata said Pura had suffered from mental health problems for a long time and his actions were effectively a cry for help after he earlier tried to seek help from the hospital.
There had been no further issues since this incident which unfortunately caused risk to others, he said.
Judge Paul Mabey QC remanded Pura on bail for sentencing on December 6.
The judge told Pura that he was going to call for home detention appendix with the pre-sentence report but the end sentence would be up to the judge on the day.