The ransomware attack on the HSE IT systems is having an ongoing impact on services at University Hospital Galway.
The patient records system is not currently accessible which means that clinical staff are unable to contact patients to arrange their appointments.
Most hospital services have been cancelled as a result.
However, there are some time-dependent treatments which need to continue.
Patients who are due to attend the Haematology/Oncology Day Ward for chemotherapy treatment at University Hospital Galway are asked to telephone 091 544890 or 087 9200753 between 9am and 5pm for advice on their appointment.
The hospital is trying to accommodate day case chemotherapy where possible.
Patients who have questions about their radiotherapy treatment can call the following numbers for advice: 091 542603 (radiotherapy booking) or 091 542607 (nursing) or 091 542523 (admin) between 9am and 4pm.
Patients who are due to attend the Rapid Access Lung Service at University Hospital Galway and Merlin Park University Hospital are asked to telephone 087 702 4370 or 087 405 7106 between 9am and 5pm for advice on their appointment.
Updates are available on hse.ie and saolta.ie