That's an increase of nearly 50 on last year's figures.
The INMO is imploring the HSE to ''look after its staff'' as record overcrowding in Irish hospitals is expected in the new year.
The organisation says the Health Service executive has left it too late as the situation was predicted back in July of this year.
Over 5,500 patients have been on trolleys in midlands hospitals this year - 3,016 in Mullingar, 1,447 in Tullamore and 1,054 in Portlaoise.
That's an increase of nearly 50 on last years figures, when the total number of patients waiting on beds in the region was 5,470.
According to INMO members care in hospitals is now unsafe due to pressure on the healthcare system.
General Secretary of the INMO, Phil Ni Sheadhaga, says nurses and midwives are under serious pressure:
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