I searched the Irish Family History Foundation's database. It contains 11,500,000 survivng rcds for abt 60% of Irish counties. Rcds B4 1840 are sparse.
For Patrick Hughes Jr. B 1846 +/- 4 yrs, I found 5 B rcds: 1842, 1845, 1846, 1846 & 1850. One of these rcds MAY be for your ancestor. 16 of 20 Louth parishes were keeping B rcds for this era. Thus there is abt a 75% chance that his rcd survived.
For a Patrick Sr and Bridget marriage 1841 +/- 4 yrs, I found 4 M rcds for Patrick: 1840, 1840, 1843, 1845. For Bridget, I found 1 M rcd in 1841. There are no potential matches.
Google the Foundation's name to lead you to this database. Pls post your search results to my Genforum msg.