People with cancer are among the patients who have been told their operations have been cancelled as the effects of the latest Covid-19 surge take hold.
72-year-old ovarian cancer patient is now facing an indefinite wait for potentially life-saving surgery after an operation due to take place on Thursday was cancelled at the last minute.
Doctors told Flo McClements, a grandmother of nine from Ballymoney, that she needed surgery as soon as possible when she was diagnosed in December.
Her son, Gregg, said: "Mum's surgeon told her the mass is quite large and might be attached to her bowel. They originally said they wanted her to have the operation between Christmas and New Year.
"They said that was the best chance of her making a recovery and so of course we're worried that any delay could completely turn the tide and ultimately that she won't make any sort of recovery. Now we don't know how long she's going to wait."
Seven hospitals in Northern Ireland were operating over capacity on Thursday, with 87 more inpatients than bed spaces. A further 226 people were waiting admission to a hospital ward, forcing health bosses to take the drastic decision to cancel the majority of all non-emergency surgery - with warnings the situation is likely to decline further in coming weeks.
The Belfast Trust has apologised after it cancelled all elective surgery this week, while staff at the Northern Trust have been contacting patients to tell them their planned operations are off.
In the South Eastern Trust, only urgent elective surgery is taking place this week and this will reduce further from Monday, when operations will only ahead for the highest priority patients.
A spokeswoman from the Western Trust said: "The trust is already at a peak in terms of Covid-19 patient numbers and projections are indicating that from the third week of January 2021, that number could be set to double. In addition, the South West Acute Hospital in Enniskillen, is already currently operating at 118% bed capacity."
Western Trust director of acute hospitals Geraldine McKay said: "This is not a simple matter of putting up more beds. Beds require staff to care for patients and pre-existing staffing pressures and staff absence of 11% and increasing daily mean that those staff simply aren't there.
"We have therefore taken the very regrettable, but necessary decision to announce as of today that routine elective inpatient, outpatient and day case surgeries will be postponed until further notice. Red flag and some time critical procedures and clinics will continue, but will be reviewed daily.
"However, we are under no illusion that if the number of Covid positive patients continue to increase at the rates predicted, the trust will have no option but to move to perform emergency and trauma surgery only."
She said this will mean operations for cancer patients will be cancelled but explained such a measure will be necessary.
A spokesman from the Southern Trust said the significant number of Covid-19 cases in conjunction with an increase in trauma patients following on from the icy weather has forced the trust to suspend elective surgery this week "in order to provide timely surgery to time critical fracture patients".