The Scottish Government has approved the full business case submitted by NHS Highland earlier this month.

The Critical Care Upgrade will bring all critical care services, which includes the Acute Medical Assessment Unit, the Intensive Care Unit, Surgical High Dependency Unit, theatre and the admissions area, into one area over two floors.

The operating theatres at the hospital will be refurbished and an additional theatre will be added to bring the total number of theatres in this area to 10, seven of which will be equipped with specialist laminar air flow, ensuring the air within the theatre environment is at the cleanest possible standard.

The work, which will be carried out by Graham Construction, will start in April this year and, while a construction programme is yet to be finalised, completion is expected at the end of 2018.

Ron Coggins, clinical director for surgical and anaesthetics division at Raigmore Hospital, said: “This investment will not only greatly improve the facilities but also provides an opportunity to co-locate wards and ensure that first-class healthcare can be delivered in modern facilities for years to come.

“Having critical care services over the two floors will not only allow best use of space and staff but it will also improve patient flow in the hospital and the privacy and dignity of our patients.”

The original building at Raigmore Hospital, which services the population of the Highlands as well as Moray and the Western Isles for some specialities, was constructed in 1980.

A number of improvement works have already been carried out including refurbishment of some of the wards and the provision of a new, state-of-the-art endoscopy unit.

Linda Kirkland, director of operations for NHS Highland’s Inner Moray Firth Operational Unit, said: “This is fantastic news for everyone associated with the hospital and for everyone who uses it now and will be using it in years to come.

“A lot of hard work and long hours have gone into making this idea a reality. This is the biggest investment in the hospital since it was built and will really transform the facility. I’m looking forward to seeing it progress.”

Health secretary Shona Robison added: “I welcome this investment in critical care services at Raigmore which will significantly improve the facilities at the hospital.

“Bringing together the hospital’s critical care services will benefit patients and improve patient flow through the hospital.”

The investment comes over and above the £29m funding NHS Highland has already secured in principle from the Scottish Government for proposed new hospitals in Aviemore and Broadford on Skye, as part of a wider redesign of health and social care services.