My parents want to protect house from Medicaid in Irrevocable Trust

My parents (79 and 78 yrs old) are exploring putting their house in an irrevocable trust in the event one of them has to go into a state run assisted living home. They would be left with very little monthly income to live. Less than their monthly bills. But an irrevocable trust has a 5 year look back period. My question is, if one of them needs to go into a home before the 5 year look back period, can the trust be set up that it could sell the home, or do a reverse mortgage, at that time one of them needed to go to home? Sort of a "triggering" event for the trust to sell the home? The house is in New York. Thank you.