HSE says there are delays for there for "patients who need non-urgent care."
A Kildare man has spent almost 17 hours in Naas General's Emergency Department, without seeing a doctor.
John Kenna, from Kilcullen, attended on Monday, and was coughing up blood.
He had returned to his home from an appointment at Blackrock Clinic when he became unwell.
The HSE says Naas General's Emergency Dept. is "very busy", partially as a result of the cyber attack on the executive's systems.
It says "There are delays for patients who need non-urgent care."
Mr. Kenna, speaking to Kildare Today, says he became weak from prolonged fasting while attending the ED.
Mr. Kenna joined Clem Ryan on Wednesday's edition of the programme.

Kfm Obituary Notices (Sunday)
Forensic Tests Planned After Axle Discovery In Dullard And Jacobs Probe
Analysis: Damning Reports Detail Rot, Fire Risks And Rodents At "Temporary" Celbridge Primary School
Major Curragh Community College Project Moves Ahead After Years Of False Starts
Plans For Walking Trail Within Castletown House Lands Under Consideration Subject To Removal Of Laurel
Council Blames Stolen Cars As It Refuses Warning Signs At Crash-Prone Bridge In Celbridge
Naas No-Shows Add To Driving Test Pressure As Kildare Test Queue Hits 1,975