A 21-year-old Katikati mother is taking legal action against Tauranga Hospital after she claims staff almost killed her two-year-old daughter twice with the same basic error.

Krystal Clark says her toddler Bailey-Rose's weight was incorrectly recorded by hospital staff as 27kg during preparation for an operation to remove her tonsils last week.

Bailey-Rose, 2, and Krystal Clark at their Katikati home.

Bailey-Rose's correct weight is 12.3kg and the incorrect measurements led to her being severely overdosed twice, first on the drugs she received prior to the operation on September 11.

Krystal first became aware something could be wrong with Thursday's tonsillectomy when the 45 minute operation and 15 minute recovery time dragged out to two hours.

'The nurses said that was most probably because it took her longer to come out from under the anaesthesia.

'On the discharge summary they have left out the dosages they gave her.”

She says her daughter was given a range of medication, including morphine, Propofol, Panadol, Ibuprofen and Ondansetron.

'I asked them specifically to give me the exact dosages that she's had, and they haven't.”

Krystal says Bailey-Rose was overdosed on Paracetamol, being given 400mg when the correct dose for her weight is 100mg.

'That's 300mg over. That dosage they have given her is what an adult would take and my daughter is only two and a half.”

Krystal was told following the operation staff had made the mistake. Bailey-Rose was kept on oxygen for the first 24-48 hours following the operation, she says.

'I got told I'm lucky I didn't lose her on the table. If we had stayed down in recovery any longer they would have given her more doses of morphine and the outcome could have been different.

'They were going to give it to her hourly. With a child they give it to them hourly, but because they had stuffed up her dose calculation and were giving her adult doses of morphine and everything else, it's lethal.”

Bailey-Rose was sent home from hospital on Saturday at 1pm. Upon arriving home, Bailey-Rose took a nap, but woke up and vomited everywhere.

Krystal called a health line worker, who was concerned about toxic shock due to Bailey-Rose's hand being inflamed where the IV line had been inserted.

Bailey-Rose was taken back to Tauranga Hospital, kept overnight and returned home Sunday.

Krystal, who is pregnant with her second child, remembers noticing her daughter had 'horrible stinking breath” that day.

On Monday Krystal gave Bailey-Rose prescribed pain relief but her temperature spiked and she began having difficulty breathing.

'I got her to the medical centre just in time, and the doctors there classed her ‘Status two', borderline ‘Status one'.

For emergency services, a Status one patient is critical.

Bailey-Rose was unable to breathe on her own and her temperature was continuing to rise. Staff recorded a temperature of 40.1 degrees Celsius, says Krystal.

With her condition visibly deteriorating, Bailey-Rose was rushed to the Tauranga Hospital's Emergency Department where the infection from her tonsillectomy was stabilised.

Krystal alleges her daughter then overdosed for a second time.

The nurses again miscalculated Bailey-Rose's weight, says Krystal, and Bailey-Rose was overdosed on the glucose saline levels in her drip.

The error was picked up by a paediatric nurse who noticed an elevated blood sugar level.

Krystal wants answers. She approached SunLive on the advice of a lawyer, and is taking a complaint to the Health and Disability Commissioner.

'You weigh them and it comes up with the number. I've been wracking my brains trying to figure out what caused them to stuff up.

'Most of the doctors were saying ‘This is a serious overdose and we are very sorry', but the surgeon couldn't even apologise.

'He came up and I bit his head off a bit, said ‘This isn't on'.

'That really upset me. Before her surgery we were in hospital pretty much monthly suffering from seizures because she would get raging tonsillitis.”

Krystal says the ordeal has left her with a complete lack of trust in health professionals.

'I don't feel safe going to Tauranga Hospital anymore. It's completely blown me out of the water.

'The nurses up in paediatrics are the only ones who have been apologising. There's been no sincere apology from the surgeon or the nurse or emergency department staff downstairs.”

The Tauranga Hospital Board will not make any comment on this story until it sees a signed permission from Krystal.

SunLive sent through a signed permission slip this morning and is awaiting the hospital's reply.