A MORBIDLY obese NSW woman who died after undergoing gastric balloon surgery wanted to make sure she was around to see her grandchildren grow up, her son says.

Margaret “Margot” Pegum, 68, had procedures done in April and June 2015 to help her to lose weight but subsequently began vomiting and had to have emergency surgery, with Sydney doctors discovering a five-centimetre hole in her stomach wall.

By July 5 doctors found Ms Pegum had multiple organ failure and sepsis. She was placed in palliative care before dying.

Speaking outside Glebe Coroner’s Court on Tuesday, James Pegum said his mother elected to have what she considered a safer and less invasive surgery, so she’d be able to help raise grandkids.

“Obviously that didn’t happen,” he told reporters.

Mr Pegum — who already has one child with his now pregnant wife — choked back tears when describing his mother as a wonderful and generous woman.

“She would have been a great grandmother ... it’s been pretty harrowing for all of our family.” Mr Pegum didn’t seek to apportion blame for what he called the “surgical mishap” but wants Margot’s memory honoured with strong recommendations for a professional standards body with guidelines on weight-loss surgery.

“At the moment there is no-one overseeing the activities of well-intentioned doctors and surgeons across Australia — they’re not accountable to anybody,” he said on Tuesday.

“If we can have her death not be in vain, and we can save other families, that’ll make us sleep better at night.”

Counsel assisting, Jason Downing, said following the initial operation in April 2015 Ms Pegum, who had weighed about 109 kilograms, became frustrated that she still felt hungry.

The adjustable gastric balloon was further inflated in another procedure on June 22 but Ms Pegum was soon repeatedly vomiting and dry retching. She became so ill with abdominal cramping that her son took her to hospital.

“I wish I’d done it earlier ... you blame yourself,” Mr Pegum said.

Margot Pegum underwent emergency removal surgery at Prince of Wales Hospital where the stomach tear was found.

Her condition deteriorated and by July 5 she had gangrene in her colon and her bowel was beyond repair. She died one day later.

The inquest will explore whether Ms Pegum was an appropriate candidate for the surgery given her history of severe acid reflux and the partial fundoplication procedure she underwent in 2012 to address it.

The surgeon who performed the balloon surgery said he warned Ms Pegum about the risks of a gastric perforation which could be a potentially fatal complication — but the court heard his patient consultation notes were “scant”.

Dr George Marinos has since changed his practice to no longer operate on patients with a history of partial fundoplication.