Just 6 percent of ambulances attending Sligo University Hospital in May were turned around for their next call within 30 minutes.
That's according to new data released by the Saolta Hospital Group showing ambulance clearance times at local emergency departments, with Sligo having the second lowest response locally.
Elsewhere in the Shannonside region, over 13 percent of ambulance crews were able to signal a clear and available status for their next call at Portiuncula Hospital in Ballinasloe in the same period.
The time covers the period from when the ambulance arrives at the ED, to the transfer of the patient, the handover briefing of hospital staff and disinfecting and cleaning the vehicle.
Despite repeatedly recording the highest trolley numbers in the country, University Hospital Limerick had the highest turnaround times in the region, with close to 30 percent of ambulances cleared under a half an hour.