The family of a woman who died after a do-not-resuscitate order (DNR) was put in her records said they had no knowledge of the decision.
Sonia Deleon, who had learning disabilities and schizophrenia, died in Southend University Hospital of a heart attack after contracting Covid-19.
Miss Deleon's sister Sally-Rose Cyrille said her sister's life had been "written off".
The hospital trust said the order had been agreed with Miss Deleon's family.
Ms Cyrille contests this.
"We had no consultation," she said.
"At no point were we told that had taken place.
"We would have disputed that and we would have said, 'we don't want that in place'."
The Care Quality Commission (CQC) has conducted a review into "blanket" DNRs made at the start of the pandemic.
Her family said Miss Deleon, known as Sone, had had her care in her final days in April influenced by her lifelong conditions.
The 58-year-old, who lived in residential care in Southend, Essex, was first admitted to hospital with a fever and respiratory problems.
She tested positive for Covid and a DNR was placed in her medical notes.
The hospital claimed a DNR which referenced Ms Deleon's learning disabilities had been incorrectly filled in and another order which did not note them was used instead.
The hospital said the DNR had been discussed with Ms Cyrille and her mother, but the family said there was no communication about the order.
"I can't describe the love my mum has for Sone," Ms Cyrille said.
"There is no way that she would agree to that being put in place - absolutely no way at all."
Ms Cyrille said her sister had had "an absolute zest for life".
"She loved being with her family, always smiling, always laughing.
"I felt like Sone was totally written off. She was devalued, dehumanised and her life was not of value.
"I just thought it was morally and ethically reprehensible. It just shocked me to the core."
An external review of Sonia Deleon's hospital care found it fell short of expected good practice.
'Unaware of decisions'
A review by the CQC of DNR decisions during the pandemic found "worrying variations in people's experiences".
The organisation spoke to people "who were not properly involved in decisions, or were unaware that such an important decision about their care had been made", the report said.
The review found there was "poor involvement of people using services, poor record keeping and a lack of oversight and scrutiny of the decisions being made".
Diane Sarkar, chief nursing officer for Mid and South Essex NHS Foundation Trust, which runs Southend University Hospital, said: "Our sincere thoughts and condolences are with Miss Deleon's family, and we welcome them to continue to discuss any concerns they have with us.
"The do-not-resuscitate order that was agreed with Miss Deleon's family and was in place throughout her care made no reference to learning disability, and she was treated appropriately based on assessments by clinicians."