Liebermeister's rule

Liebermeister's rule concerns the increment ratio between an adult individual's cardiac frequency and temperature when in fever. Each Celsius grade of body temperature increment corresponds to an 8 beats per minute increase in cardiac frequency. An exception to this rule by creating a relative bradycardia is known as Faget sign (pulse-temperature dissociation) common in some diseases, especially yellow fever and salmonella typhi.

It is named for Carl von Liebermeister.

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