One key aspect of the style of Kesey in this novel is his choice of narrator. Bromden is a particularly interesting choice of narrator for this novel, which is based so much around the theme of mental health and the definition of in/sanity, because, as it becomes very quickly evident, the reader is very unsure about the extent to which Bromden is entirely reliable due to his mental state. For example, he says that there is a fog machine that is used to cover the ward in fog and that even the pills have tiny machines in them. Note the following description of Nurse Ratched at the beginning of the novel as she gets angry with the orderlies:
So she really lets herself go and her painted smile twists, stretches to an open snarl, and she blows up bigger and bigger, big as a tractor, so big I can smell the machinery inside the way you smell a motor pulling too big a load.
Bromden himself admits that he is placed on a very high level of medication, and the reader quickly begins to see that his state of mental health is responsible for the somewhat bizarre events that he narrates. However, Kesey uses this unreliable narrator to chart the impact of McMurphy on the patients as a whole. This is of course most notable after the World Series stand off when Bromden notes "there's no more fog any place," identifying that McMurphy is helping the patients to see more clearly.