INJURIES and illnesses contracted during one of the worst winters on record have been blamed for the number of bed blocking patients hitting an 18-month high in the Lothians.
NHS Lothian currently has more than 100 patients occupying hospital beds despite being well enough to go home.
The rise in delayed discharge cases is understood to be a hangover from the huge number of elderly patients admitted over the freezing winter period.
Many of them have now moved through the care procedure, but remain in hospital as their respective local authorities do not have the means to house them immediately.
The figure of 109 is a rise of 34 from last month, and the most since October 2008, indicating a reversing trend on the progress made in recent years.
Peter Gabbitas, the city council's director of health and social care who also works with NHS Lothian, said: "109 patients were delayed overall and the Lothian partnership did not meet the two national standards."
The surge in elderly people being admitted with hip injuries and respiratory infections over December and January saw the health board struggle to cope with the queues at accident and emergency and other departments.
And an outbreak of the winter vomiting bug norovirus led to 30 additional bed blockers the previous month.
Mr Gabbitas went on: "The patients affected have primarily been in the Royal Infirmary and Liberton Hospitals, although delays have been experienced in other Lothians hospitals.
"All four partnership council areas (Edinburgh, East Lothian, Midlothian and West Lothian) have worked closely with care and nursing homes to enable, where appropriate, placements to be held open for the patients."
Despite the co-operation between the health board and local authorities, bed blocking is a subject which irks senior NHS Lothian bosses. They feel it is usually the responsibility of a council to house a person causing delayed discharge, yet it is the NHS which has to deal with that failure.
East Lothian continues to be the place where most problems are experienced, due to a larger elderly population and the recent closure of two care homes, while Edinburgh and Midlothian also contribute to the issue.
Over the past year West Lothian has barely had a patient on the bedblocking list. Delayed discharge has also contributed to NHS Lothian's status as having the highest average bed occupancy in its hospitals for all of mainland Scotland.
88 per cent of hospital beds were filled in 2009, leading critics to say it did not leave enough flexibility for large-scale emergencies or outbreaks in certain areas.
Cllr Paul Edie, Edinburgh's health and social care leader, added: "In the context of one of the worst winters in living memory and the norovirus outbreak I think it is quite impressive that the numbers have remained quite low.
"If you compare the figures to several years ago it demonstrates huge improvement, and NHS and council staff should be praised for this."