The poem by the Venezuelan writer that Paul (Sean Penn) quotes when he's in the restaurant with Cristina (Naomi Watts) is "La Tierra Giró para Acercarnos" by Eugenio Montejo.
The story in Cruising Paradise that the pictures are marking is called "The Hero is in His Kitchen". It revolves around a payphone conversation between two men, one in Tucson, Arizona and the other in Los Angeles, California. One of the last things said on the last page of the story (the one the pictures are marking) is "Don't buckle under the weight of a heavy heart!"
When Paul goes in for his heart transplant, a close-up shows a needle being used to give him an injection into an IV port. The IV port shown is a "needle-less" type and does not work with needled syringes.
When the doctor is listening to Paul's heart, he has his stethoscope in backwards. The ear pieces are supposed to face forward, but his are obviously facing backwards. In that position, not only would they hurt his ears, they would also hinder his ability to listen to the heart.
On one occasion when in Church, there is a close view of Jack, standing for a hymn. The audio is congregational singing. Jack is not singing, but the black guy to his right is singing enthusiastically, but not anything like what the rest of the church is singing,
Cristina Peck: You know what I thought when mom died? I couldn't understand how you could talk to people again, how you could laugh... again. I couldn't understand how you could play with us. And no, no that's a lie, life does not just go on.