Dans le film, la prison où Bane fout Wayne est constamment qualifiée de "pit" (fossé), je me demandais si c'était une référence au Lazarus' Pit de la BD qui permet à Ra's Al Ghul d'être immortel.

C'est précisément ça, en plus précis encore :

The Pit Prison where Bruce Wayne is imprisoned after his initial encounter with Bane is stated to have originally been a place where plague victims were sent to avoid contaminating the population. In ancient times, such places were known as Lazarettes, referring to the famous Biblical leper Lazarus, whom Jesus raised from the dead. This is a literalization of the Lazarus Pit, which in the original Batman comics is where Ra's Al Ghul bathes to keep his also literal immortality. Thus, when characters escape the Pit Prison in the film, they are said to have "risen."