Brianna's parents said at a news conference Friday that the statement issued by the hospital failed to entirely portray what happened to their daughter. They said she died not from a single mistake, "but a cascade of failures" in a system without enough safeguards."

"Losing a child is one thing, but losing a child the way it happened with Brianna is really hard," the child's mother, Mindie Cohen, said before breaking into tears.

An autopsy was not performed on the child at the family's request, but tests following the death showed "excessively high levels of potassium" in the Total Parenteral Nutrition solution, which contains proteins, fats,
vitamins, minerals and other nutrients, the statement said. The amount of potassium was four to five times higher than called for, the Children's Center said.

"Although our analysis is incomplete, and we are as yet unable to recreate the precise series of events that occurred, Hopkins fully accepts that then most likely explanation for this tragic event is that human error occurred
in the manual formulation of the solutions," the statement said.

Miscommunication between the hospital and one of its pharmacies may have been a contributing factor, the hospital said.

In response to the death, the hospital said the preparation of all Home Care TNP solutions for children and adults will be done by fully automated systems now used for Hopkins inpatients.

The family's attorney, Gary A. Wais, said Brianna's potassium level steadily rose in three days leading to her death. The father, Mark Cohen, said the hospital staff ignored the trend.

A lawsuit has not been filed, and Wais said there has been no discussion regarding a settlement.

In 2001, the Children's Center launched a patient safety initiative after the death of an 18-month-old. The toddler died after the staff failed to treat her for severe dehydration.