Andrew Smith was already serving a 12-year jail sentence for previous assaults when he was transferred to Langdon Hospital, Dawlish, for psychiatric treatment late 2020.
He chased a terrified student nurse down a corridor, smashed her face through a window, and carried on punching her until he was dragged off by other staff.
He was angry because she had refused to fetch a replacement vape cartridge for her and told him he would have to go to a medication counter to get painkillers.
She noticed him staring at her menacingly and followed her after she left his room, chasing her down a corridor. She sought refuge in a television room and took shelter behind a sofa but he pursued her out.
The nurse almost made it back to the safety of her office but stumbled as she fled and he caught up with her and attacked her.
Colleagues did not recognise her because her face was so heavily blood-stained. She made a victim impact statement which said she has been left physically and emotionally scarred and is reassessing her career choice.
Smith, aged 37, who is now serving his sentence at HMP Oakwood in Staffordshire, admitted assault causing actual bodily harm and was jailed for eight months by Judge Stephen Climie at Exeter Crown Court.
The new sentence will be added to the 12 years he is already serving for an offence of causing grievous bodily harm with intent for which he was jailed in 2014.
The judge told him: “You have a significant record for offences of violence and was aggravated by being committed against someone who was doing all they could to help you. You have put her entire career at risk.”
Mr Brian Fitzherbert, prosecuting, said Smith was transferred to Langdon Hospital from HMP Erlestoke in Wiltshire in August 2020 after being diagnosed with psychiatric issued which was linked to his reluctance to take medication.
He was being treated with inter-muscular injections and appeared to have be improving when he carried out the attack on the nurse on October 18, 2020 while he was on an observation ward. He was returned to prison ten days later.
The incident started with him asking the nurse to fetch him a replacement nicotine capsule and her telling him he would have to obtain it himself from the medication hatch.
He went on to ask her for painkillers and she gave him the same answer and left the room, only to find him chasing her down a corridor.
She managed to get into a television room where she got a sofa between them, to which he responded by saying ‘you got pretty f***ing lucky there’. She tried to flee to a nurses’ office but slipped and he overhauled her.
She suffered a cut to her face and severe bruising from his repeated punches, which he delivered while holding her in an arm lock.
Her victim impact statement said: “I have been scarred for life mentally and physically and don’t feel safe any more.”
Mr Paul Dentith, defending, said Smith suffers from mental health issues including an emotionally unstable personality disorder. He had admitted the offence and it was no fault of his that the case had taken 15 months to reach the court.