He believed that had Mr Bedford had the nasogastric insertion, it was more than likely he would have recovered from his operation. Mr Bedford had limited capacity or insight into the consequences of not having the procedure.
Coroner Smith said the DHB could have done more to save Mr Bedford, as well as two other Wellingtonians. Chronic paranoid schizophrenia patient Lulin 'Lawrence' Wu, 53, took his own life on January 10, 2011 after missing some appointments to take his anti-psychotic medication.
"As I have said on many previous occasions, it requires a strong development of communication between parties involved with the care of a patient and, in particular, to follow up immediately with a mental health patient who did not take up an appointment or was unable to be contacted," Coroner Smith said.
He also criticised the health board over the death of Eugenia Szwetko.
The stroke victim missed an appointment for an MRI scan after dying of unrelated, but unknown natural causes.
The 69-year-old lay dead in her Wellington house for a fortnight before her decomposed body was found by neighbours on January 8, 2010.
Coroner Smith commented that the DHB needed to review its process of "ensuring that a patient is able to contacted when they fail to make and keep an appointment".
"I have stated this in the past with respect to mental health issues, but it is equally important in situations as in this case.
"I know that this places a further implication on the personnel of the hospital but the upshot is that there may be a subsequent medical issue for a patient like what happened to Mrs Szwetko."
Alison Masters, the DHB's executive director of mental health, addictions and intellectual disability, said it had reviewed its processes around what to do when a mental health patient did not show up for an appointment.
"We make every attempt to contact high risk patients who do not attend. We are continuing to review our communications processes and make improvements, most recently focussing on our monitoring process with GPs."
Dr Masters said compulsory treatment under the Mental Health Act did not necessarily mean patients like Mr Bedford had no capacity to consent to medical treatment.
"In the circumstances of this case it was the judgement of the medical team that it was not appropriate to override the wishes of the patient."
Responding to Mrs Szwetko's case, DHB chief medical officer Dr Geoffrey Robinson said the board had a "robust process" in place for when patients missed a radiology appointment.
The coroner's criticism comes just months after he blasted the same health board for failings in relation to three Wellington suicides from November 2008 and August 2010.
The most stark example was that of young mum Leigh McGuinness, 27, who committed suicide after being refused help by mental health workers who said their shift was nearly over.
