Lyn Copland, Fischer's mother, became visibly upset when the psychiatrist said he did not believe Fischer had concussion after the incident.
Copland shouted "he had concussion and a head injury, and he should have been observed,
"He should have been observed every half hour for twelve hours."
Coroner Ryan asked Copland to leave the room. She later returned.
Copland's lawyer, Letizea Ord said the family had concerns the head-banging incident caused concussion and there wasn't a direction for more observations.
The psychiatrist disagreed and said there was no signs of confusion recorded.
"For it to have caused significant damage to cognitive changes, there would be clinical signs on examination."
Fischer had an extensive mental health history extending back to the 1990s. He was diagnosed with bipolar disorder complicated by cannabis and alcohol substance abuse.
He was admitted voluntarily to the crisis mental health team in early 2015 and kept in the acute inpatient unit under the Mental Health Act as a patient for three months.
Police were aware of seven incidents of Fischer harming or attempting suicide between 2000 and 2010.
They included overdosing on drugs and mentioning he had "had enough".
Two reports have found risk documentation surrounding Fischer's care was not adequate and that has been accepted by CCDHB.
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.
Or if you need to talk to someone else:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633
• Need to talk? Free call or text 1737 (available 24/7)
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• Samaritans 0800 726 666
• Rural Support Trust: 0800 787 254.