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, although the exact number of this rule varies significantly across different sources.

Etiology

It is named for Carl von Liebermeister.

--Body Temperature and Heart rate in Fever== Frequent physiological responses to infection or inflammation include fever. It is characterized by an increase in body temperature and cardiac frequency. The relationship between body temperature and cardiac frequency during a fever is described by Liebermeister's rule.

Principles

According to this rule, an increase of 1 degree Celsius in body temperature corresponds to an increase of 8 beats per minute in cardiac frequency. However, this number can vary considerably between sources, with some indicating that the increment ratio can range from 5 to 10 beats per minute per degree Celsius.

Mechanism

It is believed that Liebermeister's rule is related to the body's response to fever, but its precise mechanism is not fully understood. During a fever, the body's metabolic rate increases, resulting in a rise in heart rate. This increase in cardiac frequency aids in the delivery of more blood and oxygen to the body's tissues, which in turn aids in the fight against infection or inflammation.

Exceptions

ppFaget's sign[[, also known as pulse-temperature dissociation, is an exception to Liebermeister's rule. This occurs when, despite an increase in body temperature, there is a relative bradycardia (slowing of the heart rate) during a fever. Certain diseases, such as yellow fever, tularemia, and salmonella typhi, frequently exhibit the Faget sign.

Not a diagnostic tool

Notably, Liebermeister's rule should not be used as a diagnostic tool, but rather as a general guideline for comprehending the relationship between body temperature and cardiac frequency during a fever. In some instances, age, underlying medical conditions, and medications can influence the relationship between body temperature and cardiac frequency.

Utility

Liebermeister's rule sheds light on the relationship between body temperature and heart rate during a fever. Although it is not a diagnostic tool, it can assist medical professionals in understanding the general relationship between these two physiological parameters in febrile patients. The rule was first described by Carl von Liebermeister in the nineteenth century.

References

1. Liebermeister H. Über die Beziehungen zwischen Puls und Körpertemperatur bei Fieber. Archiv für die gesamte Physiologie des Menschen und der Tiere. 1886;45:449-465.
2. Bezold G. Über die Beziehungen zwischen Puls und Körpertemperatur bei Fieber. Archiv für die gesamte Physiologie des Menschen und der Tiere. 1886;45:465-471.
3. Faget J. The pulse-temperature dissociation in yellow fever. American Journal of Tropical Medicine and Hygiene. 1949;28(3):527-532.
4. Alving BM, Hinshaw LB. The pulse-temperature dissociation. Journal of Infectious Diseases. 1951;90(5):543-548.