At least three hospital chaplains in Dublin have said that recently patients have died without being able to see a priest.
Caroline Mullen, a chaplain at Connolly Memorial Hospital in Dublin, said: "There are many people who die who don't have the Sacrament of the Sick. [The priest] can't be there all the time."
The Archdiocese of Dublin has admitted that, due to a lack of clergy and cuts in hospital funding, they have a policy of not replacing chaplains who have retired.
Increasingly in England, priests are no longer employed as full-time chaplains to hospitals, with parish priests visiting patients and being on call.
Bishop Tom Williams, chairman of the Healthcare Reference Group of the Bishops' Conference of England and Wales, said that the shortage of priests meant that the role of lay chaplains was becoming increasingly important.
He said: "There are fewer priests, that is a fact. He added that priests "must not be killed of with unreachable expectations".