This is a very broad question, and so for me I am going to focus on one form of figurative language that is explored in this short story which is symbolism. One of the central symbols of this story for me at least is the pump. This pump and its unattainability seems to be a symbol of the real lack of compassion and care of humanity in the face of suffering. Consider the following passage:
In the meanwhile, more television and movie teams arrived with spools of cable, tapes, film, videos, precision lenses, recorders, sound consoles, lights, reflecting screens, auxiliary motors, cartons of supplies, electricians, sound technicians, and cameramen: Azucena's face was beamed to millioins of screens around the world. And all the while Rolf Carle kept pleading for a pump.
Note how a very short and simple sentence is placed after a long sentence which lists all the sophisticated technology that reporters bring with them. They are able to do incredible things thanks to technology, but somehow bringing a pump to save Azucena eludes them. This contributes to the somewhat sarcastic and despairing tone employed in this section as Allende laments the inability of a technologically advanced world to save one girl.
If you want to explore the symbolism in this short story further, you might want to think about how Azucena herself is a symbol, as is the camera that Rolf Carle uses to protect himself from the world and ultimately, himself.