In Glasgow, the £842m flagship Queen Elizabeth University Hospital (QEUH) is currently undergoing an internal and external review after a series of healthcare-associated infections and patient deaths at the site.

Raw sewage was also found leaking into the old brain surgery theatres at the Institute for Neurosciences, which are supposed to be replaced with the new ones currently lying empty.

The £7m suites at the Imagine Centre for Excellence were initially supposed to open in 2017, before being delayed to 2018.

The Herald on Sunday previously revealed they were still lying empty in May this year.

We have obtained internal NHS documents detailing the extent of the concerns raised years before the problems at the QEUH new hospital and the old Institute for Neurosciences came to light, including issues around ventilation, sewage and infection control.

Senior microbiologists contacted NHS Greater Glasgow and Clyde's acute medical director Dr David Stewart via email in August 2015 about the brain theatres, stating: "While the ingress of raw sewage was the initial reason for infection control becoming involved, we have now identified a multiplicity of issues regarding safe functionality of the suite.

"We have very large concerns over the state of the entire theatre suite and are both of the opinion that they are not fit for purpose."

The experts stated there were problems with ventilation rates being far below what they should be, and "outside air from what is effectively a building site is readily accessing all the theatres".

Other concerns raised with Dr Stewart extended to the rest of the QEUH campus, with a consultant microbiologist contacting him on December 29, 2015 stating: "We had requested that there would be an external review of the issues raised – particularly with regard to the new build...HFS [Healthcare Facilities Scotland] and HPS [Health Protection Scotland] have become involved to a degree.....(but) HPS and Healthcare Environment Scotland have not been asked for their expert input into theatre design and commissioning, the infectious patients isolation suits or children's bone marrow transplant.

"The key here is that we are now picking up problems with regard to the building and continue to have question marks over the suitability of the accommodation."

NHS Greater Glasgow and Clyde said: "In 2015, when the new hospitals opened, there were a range of issues raised as would be expected in any new building which local managers sought to address."