Wait, as I put the light down his throat
I can only see flow his blood starting to flow
Although the brain is technically the origin of a rapper’s flow, the throat acts as a conduit for it and is therefore the area to inspect for signs of life. Since the patients are a metaphor for hip hop, “blood starting to flow” would be a product of lyrical flow improving and bringing life to the person (or genre) Dr Carter is trying to save.
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