KEY questions about what went wrong in the construction of Edinburgh’s new children’s hospital “remain unanswered”, Scotland’s public spending watchdog has said.

Caroline Gardner, Auditor General for Scotland, said it was clear than checks and balances around the delayed Royal Hospital for Children and Young People (RHCYP) “didn’t work”. 

In particular, Audit Scotland said it remained unclear how a major blunder in the design of ventilation for the critical care and paediatric cancer units occurred. 

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The vents should have been capable of 10 air changes per hour to minimise the risk of infection in the sickest patients, but a final inspection of the facility in June - weeks before its planned opening - found that some areas, including theatre and isolation rooms, could only achieve four air changes per hour.

The watchdog said an independent review into the fiasco by KPMG “sets out a picture of human error and confusion over interpretation of the relevant specifications and guidance and missed opportunities to spot and rectify that error”. 

The Audit Scotland report reveals that it will cost £4 million to correct the issues in the ventilation systems before the children’s hospital can open in autumn next year. 

The £4m is part of a total bill for the delay of £16.05m, which includes a £2m contingency fund in case of further remedial action. 

The main contractor for the design and construction of the RHCYP was Brookfield Multiplex, a Canadian-headquartered construction giant who also built the new Queen Elizabeth University Hospital and Royal Hospital for Children in Glasgow, which opened in 2015. 

On Tuesday, NHS Greater Glasgow and Clyde revealed it was taking legal action to sue Brookfield Multiplex over the project in the wake of a string of infection scandals linked to ventilation and contaminated water supply. 

Caroline Gardner, Auditor General for Scotland said:”It’s clear that the checks and balances around the construction of the new children’s hospital didn’t work, and the public inquiry may want to consider why that happened after similar issues had emerged around the building of schools in Edinburgh.

“It would also be beneficial to understand the role played by all the parties involved, and to explore why the issues that emerged at Glasgow’s Queen Elizabeth hospital didn’t prompt greater scrutiny in Edinburgh.”

The Audit Scotland report notes that the Edinburgh hospital build had been plagued by “a series of technical and contractual disputes throughout 2017 – over and above what would generally be expected on such a project”. 

NHS Lothian went on to pay IHSL Ltd - the private consortium that included Brookfield Multiplex - an extra £11.6m to carry out a number of fixes.

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The Audit Scotland report noted that the independent review by KPMG traced the ventilation flaw back to an ‘Environmental Matrix’ document produced by NHS Lothian at tender stage in 2012. This wrongly specified four air changes per hour, contradicting the stipulations set out in the Scottish Health Technical Memorandum (SHTM)

However, in January 2019, IHSL Ltd assured NHS Lothian that all ventilation systems had been designed, installed and commissioned in line with SHTM guidance. 

Susan Goldsmith, finance director at NHS Lothian, said she welcomed the Audit Scotland report “which sets out the next steps which require further investigation”.

She added: “NHS Lothian accepts that the environmental matrix was incorrect, but we would reiterate the point we made to the Auditor General that it was never part of the contractual suite of tender documents.

"The tender documents contained the explicit requirement that all relevant national standards should be complied with, and that the reference for these was the SHTM”.