A flood at Raigmore Hospital in Inverness has caused damage to its computer systems.
NHS Highland said servers which support hospital systems were “unlikely to be fully functional for day-to-day business”.
It is understood the basement flood was related to the weather rather than a burst pipe.
A health board spokeswoman added: “Both Estates and IT teams have been on site all night, supported by duty management who gave put in place paper based contingency plans for this morning.
“Whilst all inpatients are safe, there will inevitably be some impact today on computer based services as the demand on temporary systems increases. These include reports and results from both the X-ray department and the laboratories at Raigmore Hospital.
“The management team are currently engaged in minimising impact on patients and supporting staff to manage this morning with these business continuity arrangements.
“It is anticipated that there will be some detrimental impact to outpatient and theatre services, with a team of administrative staff currently contacting people with appointments for this morning.
“If you have an appointment today, or have been asked to attend Raigmore Hospital for an investigation or operation please continue with your plans unless contacted.
“Work continues on the recovery and connectivity of the servers to ensure that services will resume as quickly as possible.”