re-reading I'm still almost 2 books from that scene so I found a snippet correlating the two
Seeking shelter at the inn at the crossroads, they ran afoul of two of Gregor's men and their squire. When the two groups came to blows, Sandor killed Polliver and held off the Tickler but was seriously injured in the fight due to inebriation and hunger. The two were victorious, and though Arya dressed his wounds, they quickly became infected; still hating him, Arya refused to grant him the mercy of a quick death. She abandoned Sandor to die under a tree by the Trident, and his fate becomes uncertain after this point
http://awoiaf.westeros.org/index.php/Sandor_Clegane