The INMO says this year has been the worst ever April for overcrowding in UHK since it started keeping records.
The Irish Nurses' and Midwives' Organisation has published daily trolley watch figures since 2006.
The number of patients on trolleys at University Hospital Kerry in April is now five times greater than it was in April ten years ago.
During April 2014, fifty people were admitted at University Hospital Kerry without a bed to accommodate them.
Last month (April), the figure had jumped by almost 500 percent (490.91%) to 325 patients on trolleys.
The number awaiting beds at UHK in April last year was 182.
While there were some declines in UHK's annual April figures since record-keeping began 18 years ago, the general trend is steeply upwards.
INMO General Secretary Phil Ní Sheaghdha, who's from Ventry, claims it's "clear the HSE have not learned any lessons when it comes to reducing the number of patients on trolleys".
