Indya Trevelyan, who was 20 months old, was taken to hospital with what her parents suspected was a minor case of croup, which is a common childhood throat infection.
She was given general anaesthetic so a they could look down her throat but, before they could, she began to struggle to breathe.
Consultant surgeons Simon Watts and Tony McGilligan carried out an emergency tracheotomy to cut open the windpipe and insert a breathing tube before they stitched the skin back together.
The surgeons left Indya in the care of anaesthetist Dr David Campbell, who had nine years' experience but had never taken part in a tracheotomy.
Indya began struggling to breathe and Dr Campbell noticed her breathing tube had come loose so he tried to reinsert it but the stitches accidentally broke open and the anaesthetist failed to put the tube back properly.
He called the surgeons back and Dr McGilligan noticed the problem with the tube and corrected it.
However, the toddler, who was being treated at the Royal Alexandra Hospital for Children, in Brighton, Sussex, then suffered a heart attack and had to be resuscitated.
She was moved to the intensive care unit of the Evelina Children's Hospital, in London, but she had suffered irreparable brain damage and died from multiple organ failure 24 hours later on April 18.
Indya's mother, Sian, 37, from Pease Pottage, near Crawley, West Sussex, told the inquest in Brighton that only days before she died she had been happy, smiling and dancing around but that on the way to the operating theatre she had become very distressed.
The inquest heard that the surgeons involved had "no plan for the unexpected" and "no one" had taken the lead when things went wrong.
Dr McGilligan said: "I didn't write what the sutures were there for, but it was my presumption that anyone would follow why they were there.
"The sutures were moved by theatre staff trying to replace the tube. I could see the tube had blood round it and that the tube had become displaced so I moved the trachea and put the tube back in."
Dr Watts said procedures had been changed to prevent a similar tragedy.
He added: "In hindsight I would have let everyone in the hospital know what the sutures were there for".
Speaking outside the inquest, Mrs Trevelyan, who is pregnant with her second child, said: "She was clinging around my neck and tears were streaming down her face.
"I promised her she would be alright."
She said: "We were told not to worry as it had been a success and we would be taken to see her shortly. Then this woman said to us 'The team are with her now and she is being resuscitated'.
"That was the first time we realised things were wrong. We were wondering what on earth was going on. We were told the tube had become displaced, her lungs collapsed and her heart nearly stopped."
Indya was transferred to London where Mrs Trevelyan and her husband Nigel were told she had brain damage. Their daughter died a day later.
An investigation by the Brighton and Sussex University Hospitals NHS Trust has since concluded that Indya's death was "preventable". The author of an interim report added: "This death arose out of a false assumption that systems do work."
As she awaited the resumption of her daughter's inquest tomorrow, Mrs Trevelyan said: "She was my beautiful angel. She had big blue eyes and a massive grin. Even in the hospital, hours before the operation which was going to end so tragically, she entertained junior doctors in her cot.
"People have said that losing a child is the worst thing that can ever happen, but I know that the worst thing would have been to have never had Indya in our lives."
The inquest continues.
